Semi-Dwarf Cereal Mutants and Their Use in Cross-Dreeding Iii

IAEA-TECDOC-455

SEMI-DWARF CEREAL MUTANTS AND THEIR USE IN CROSS-DREEDING III

PROCEEDINGS OF THE FINAL RESEARCH CO-ORDINATION MEETING ON EVALUATION OF SEMI-DWARF CEREAL MUTANTS FOR CROSS-BREEDING ORGANIZEE TH Y DB JOINT FAO/IAEA DIVISION OF ISOTOPE AND RADIATION APPLICATIONS ATOMIF O C ENERG FOOR AGRICULTURAD YFO D AN L DEVELOPMENT AND HELD IN ROME, 16-20 DECEMBER 1985

A TECHNICAL DOCUMENT ISSUED BY THE INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1988 SEMI-DWARF CEREAL MUTANTS AND THEIR USE IN CROSS-BREEDING IAEA, VIENNA, 1988 IAEA-TECDOC-455

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A Co-ordinated Research Programme on the "Evaluation of semi-dwarf mutants as cross-breeding material in cereals" was initiated in 1980, with the main objective to provide cereal breeders with new, alternative sources of genes for semi-dwarf, lodging resistant plant types. In the early 50's it became obvious that lodging, cause y longb d , weak stra d leadinan w o t g w responslo a o nitroget e n fertiHzation e maith n s reasowa , n which limited the yield potential of cereals, particularly in good agro-ecological conditions. This proble s increaseha m d drastically with the use of higher doses of fertilizer. Introduction of genes responsible for short stature plant type from certain local forms to wheat and rice cultivars solved the problem and led to better utilization of water and nitrogen input y transferrinB . g such genes new, intensive cultivars were developed - which initiated the agro-economical changes now described as the "Green Revolution".

Unfortunately w , somfe onl ia dwarfiny g gene sources, usefu r crosfo l s breeding, were foun n germplasi d m collections around the world. The very narrow genetic variation for this character has generated a risk of genetic vulnerability towards pests, disease d othean s r e hazardsotheth rn O hand. , short stature forms of cereals are frequently selected after mutagenic treatmen f radiatioo e us tr chemica o e witn th h l mutagensA . number of modern semi-dwarf cereal varieties, directly developed from selected mutants, were released in various countries, but a long list of other short stature mutants induced in different laboratories needed evaluation for use in cross breeding. It was the ultimate aim to identify and make available new sources of semi-dwarf plant types and in this way open possibilities for varietal improvement beyond the limits set by the presently used gene sources and by the same means reduce the genetic vulnerability.

The present publication includes papers presented at the the final Research Co-ordination Meeting. Papers presented by participant e Co-ordinateth n i s d Research Programme (see "Project Reports") demonstrate that these objectives were successfully n achieveda additiona s A . l resul f o thit s programme more improved genotype f o cereals s with other desirable characters as earliness, better harvest index and improved plant architecture have become available for practical breeding. EDITORIAL NOTE

In preparing this materialpressthe International the fut staff o] Atomic Lnergi \t><.nc"i have mounted paginatedand onginalthe manuscripts submittedas author gmn the b\ and some attention ptesentationthe to e\pressedS Thpapers,e WH eth statementse n i th generale th made d an st}le adoptedt a/ the responsibiht\ of the named authors The views do not necessanl\ reflect those of the go\ein- mentsoftheMembLi States organizationsor undei wl\ose auspices manuscriptsthe \\-ete pioduud thisin The bookuse of panicular designations countnesoj nonesten or does unpl\not an\ judgement b\ the publisher, the IAEA, as to the legal status of such countnes or terntonts of their authonties institutions and delimitation the of 01 theirof boundaries The mention specificof companies thenof or products brandor names does unpl\not am endorsement recommendation01 IAEA partthe the of on Authois are themselves responsible foi obtaining the necessar\ peimission to reproduce cop\ right material from other sources CONTENTS

INTRODUCTORY PAPERS

9 Biotechnolog d mutatioan y n breeding P S Baenziger Activit Institute th f o y f Experimentao e l Researc5 1 r Cereahfo l Crops, Rome A Bianchi Gene manipulation by mutation techniques 19 M Malusz\nski, B Sigurbjornsson, A Micke

PROJECT REPORTS

Examination of dwarf wheats produced by mutation, crossing and physiological procedures 33 Z Barabas, Z Kertesz Evaluatio f semi-dwaro n 3 4 f mutant tnticaln i s d wheaan e t breeding CJ Driscoll Evaluatio f mutanno t stock r semi-dwarfo s f plant typ s materiaa e r crosfo l s breeding 9 4 in durum wheat K A File\ The exploitation of the Tom Thumb dwarfing gene, RhT^ in F, hybrid wheats 57 MGale,D Salter,AM Curtis,FC AngusWJ Comparison of two semi dwarfing genes on yield performance of durum wheat lines 69 B Giorgi Genetic analysis, genetic improvemen d evaluatioan t f induceno d semi-dwarf mutants in wheat 77 C F Konzak Barley mutants in relation to culm length 95 U Lundq\ ist Agronomic and genetic evaluation of induced mutants of White Luchai-112 103 P Narahan Evaluation, inheritance d gibberellian , n respons f induceo e d semi dwarf5 mutant12 f rico s e J N Rutger, T R Anderson Mutation breeding for semi dwarfism in barley 135 S E Ullrich, A A\dm Selectio f colo n d tolerant mutant line naken i s d barle5 14 > (Hordeitm \ulgate ) L L JWon, H Chung G Genetic analysis of induced semi-dwarf mutants in rice 149 H Yamagata, T Tamsaka, M Tomita K Shiraishi

INVITED PAPERS

Transfe f alieo r n genes into cultivated whea tnticald an t f o e e genotypeus e th y b s 5 16 homoeologous pairing mutants C Ceolom Effec f gammo t a radiatio7 17 n immaturo n e wheat embryo culture Mmguei Gao, Zhugmg Liang, Ziongymg Chen In vitro culture in barley breeding 183 K N Kao Semi-dwarf mutants and heterosis in barley I The use of barley sd-mutants for 3 19 hybrid breeding M Malusz\nski I Szarejko, R Madajeuski, A Fugle\\icz, KucharskaM Biochemica7 20 l aspect f cold heao s an dt shock respons barlen i e y N Marmiroli Komjanc,M C Lorenzom, M Odoardi, V Terzi, StancaM A Physiological test r drough1 fo s 21 t toleranc barlen i e d duruan y m wheat P Martiniellü G Boggim Comparative anal}si e morphologicath t a s l biochemica genetid an l c leve develoo t l p a strategy for stud>mg biological similarities in Triticinae 219 L Montebo\e Pacede C Agronomic evaluation of induced semi dwarf mutants in durum and common wheat 231 C Mosconi B Giorgi Semi-dwarf mutants and heterosis in barley II Interaction between several mutant genes responsible for dwarfism in barley 241 / Szarejko M Malusz\n<>ki, M Nanrot, B Skaumska-Zydron mutane dwarfin1 r> e EffecEM tth f o gt gen octon o ed hexaploi an - d tnticale 7 24 Preliminary report T Wolski E T\mieniecka Winter tnticale breeding in Poland 251 T Wolski

List of Participants 255 INTRODUCTORY PAPERS BIOTECHNOLOGY AND MUTATION BREEDING

P S BAENZIGER Monsanto Agricultural Company, Chesterfield, Missouri, United States of America

Abstract

Mutation breeding has been successful. New biotechnological techniques such as in vitro mutagenesis, in vitro selection, and haploidy may assist in, or improve mutation breeding where applicable vitrn I_ .o mutagenesis will increase the specificity of the mutation process, ^tn vitro selection and haploidy will improve mutation identificatio d selectioan n n capabilities. These techniques, their uses, and their limitations are discussed.

Mutation breeding has been unattractive to many plant breeders becaus e techniquee th man f o v r inducinfo s d an g selecting useful mutations involve random mutationr fo s qualitative traits coupled with large screens of the mutated plants and/or their progeny. Most breeders prefe o wort r k with predictable variation by hybridizing parents with known genetic qualities. Mutation breeding has been suggested where there is little known variation for a trait of interest or where an otherwise excellent cultivar is missing a single trait that may be introduce y mutation b de latte th n I r . case, mutation breeding replaces backcrossing. The promise and successes of mutation breedin n seed-propagatei g d crops have been recently reviewey b d Konzak, et al (1984). Mutation breeding has provided both novel gene d allelean s s with previously known phenotypes betten i t r,bu adapted backgrounds. The impact of biotechnology on mutation breeding will be significan biotechnologf i t n alleviatca y e th som f o e constraints and limitations of mutation breeding. Three areas where biotechnology may improve mutation breeding are: (1) in vitro mutagenesis; (2) 111 vitro selection; and (3) the use of e identificatioth n i haploid d ai o mutationsf t yo n . The methods and applications of iji vitro mutagenesis, for this paper narrowly define mutations a d A outsidDN a celf o sf lo e or organism, have recently been comprehensively reviewed by Botstei d Shortlnan e (1985) n thiI .s technique a ,gen clones i e d and the s mutatei n d (usuall a smal n o yl cloning vecton i r Escherichia coli) either by restructuring segments of DNA, localized random mutagenesis r oligonucleotide-directe,o d mutagensis. In the first type of mutagensis, the gene is usually mutate y systematicallb d y deletin d thean n A g DN portion e th f o s assaying the gene to see if it still functions. In this method e functionath l e delineate aspectb e gene n th th ca e f n o sI d second type of mutagenesis, a small fragment of the cloned DNA is isolated, exposemutagenie th o t d c treatment d thean , n alloweo t d recombine wit e intactth h , larger cloned genee valuTh .f thio e s method is that only a relatively small portion of the DNA is exposee mutagenith o t d c treatmen o thas t t unwanted, secondary mutations in the DNA may be limited. In the third type of mutagenesis, the mutation of interest is synthesized de novo in aa singls e strande A oligonucleotidDN d d allowean e o t d reannea wila o dt l typ e oligonucleotid th gen r o e s i e synthesized d£ novo as double stranded DNA and then inserted into a larger DNA sequence containing the remaining parts of the gen f intereso e t (both methods givin precisela g y mutated gene). The advantage of in vitro mutagenesis is that relatively small portions of the genome are exposed to the mutagen. The disadvantage A sequence genDN th f e o r th fo e tha) ar s(1 t interest musmutatione e knownth tb ) (2 ; s wille b nee o t d assaye n expressioa n i d n system e cro (ofteth whicn i pe t th nno h gen s identifiedewa determino )t e their efficacy, e whicb n ca h laborious e usefub ,r somo t andfo l e ) application(3 , n i s modifying the organism of interest, the ^n vitro mutation should be inserted to replace the wild type allele (Botstein and Shortle, 1985) If the desired mutation is recessive, then it will have to be inserted to replace the wild type allele or the wild type allele will have to be inactivated. A dominant or co-dominant mutation will be expressed regardless of where it is inserted and need not replace the wild type allele to have the desired phenotype. In cereals, most gene f intereso s e unknowar t verd an ny difficult to identify. Transposon mutagenesis where the transposon sequenc s knowi es bee nha n use n cor i do identif t n y and clone genes (Fedoroff et al, 1983; Fedoroff et al, 1984; O'Reilly et al, 1985). Transposon mutagenesis is particularly useful when only the desired phenotype is known. Biochemical knowledge of the trait is not necessary as the transposon sequenc e gene use b th f o probinteres o et dn r ca efo e n linei t s havin e desireth g d phenotyp o transposot e du e n mutatagenesis Species with smaller w copgenomelo y d numbean s r genes (i.e Arabidopsis thaliana y provid)ma e probe r usefufo s l genen i s cereals (Meyerowit d Pruittzan , 1985) n cerealsI . , where useful transformation systems are still being developed (Fromm et al, 1985), the mutant genes will have to be expressed in other host organisms, such as E^ coli, yeast (Saccharomyces cerevisiae), dicots, and Xenopus laevis (Smith et al, 1985; Taylor et al, 1985). Developmen f technologo t r replacinfo y wile th gd type allele wit mutana h t allele will hav waito effective for t e transformation technology. However, even with the disadvantages and technical hurdles described above, having a better understanding of the gene and the type of mutation needed, as e resultanth wel s a l t protein y lea o ,morma t d e efficient whole plant or tissue mutation strategies and better phenotypic screens. For example, if it is known that the desired mutation ia singls e ammo acid e proteichangth n i e n whic s codea i h y b d single nucleotide change from the wildtype DNA sequence, it should be possible to better choose the mutagen e vitrn valui Th f o e selection using callus, suspension, or protoplast cultures is in its ability to select variants from large numbers of potentially totipotent cells in small culture flasks with relatively uniform conditions. Its efficiency is derived from its ability to select cells that then are able to regenerate plants rather than select at the whole plant level.

10 r exampleFo , 5,000,000 plan te challengeb cell n ca s d wita h toxic chemical such as a herbicide in a single flask. It would require many hectares of land to grow five million corn or tobacco plants and it would be impossible to uniformly spray them wit a hchemical n somI .e wayvitri it s o selectioe b n ca n considere n extensioa d e see r th embryo d f o n o selective assays for useful mutations. Additionally, the culturing techniques are often mutageni y themselveb d an c s provide sufficient variation for the rn vitro selection to be effective (Larkin and Scowcroft, 1981). Mutagens also can be added to the medium to further enhance the genetic variation available for selection (for example, Chaleff and Ray, 1984). As such, in vitro selectio f cultureo n d cell bess i s t viewe a selectio s a d n method for mutations. Meredith (1984) reviewe subjece th d f selectino t g better crops from cultured cells and has described the challenges, opportunities, and pitfalls of these techniques. The main challenges are to reduce complex agricultural problems to a meaningful and relevant selection medium, have the cellular phenotype expressed in culture so it can be selected, and to have selecteth e d cellular phenotype translat usefua o t e l whole plant phenotype. Obviously, these limitations will greatly restrict the type of mutations that can be selected, but as Meredith suggested, phenotypes that involve cellular processes should be more amenable to in vitro selection. As salinity, mineral stresses, herbicide tolerances, and disease toxins all involve cellular processes, they shoul e amenablb d vitrn i o ot e selection (Meredith, 1984; Chalef Rayd an f , ~ 1984)~ . The last area of biotechnology to be discussed as a possible method to improve mutation breeding is haploidy. Haploidy and doubled haploidy have been reviewed by many authors (Collins and Genovesi, 1982; Maheshwari et al, 1982; Baenziger 1984, eal t 1985), , al e Chosignificanc Th t .e o t s ha t i e mutation breeding is two-fold. Firstly, a haploid contains only the gametic numbe f chromosomeo r o thas t both dominand an t recessive gene mutations wile identifie b e expresse b ln ca d dan mutagenizee ith n d haploid cell lin r planto e e haploiTh . d plant can then have its chromosome number doubled and the gene will be homozygou e doubleth n i sd haploid plant r exampleFo . , anthers from tobacco have been treated with mutagens to produce highly variable, haploid plants. These haploid plants were then successfully selecte r higfo dh photosynthetic efficiency prioo t r chromosome doubling (Medrano and Primo-Millo, 1985). In a mutagenized diploid plant a ,recessiv e muation woul e expresseb d d doubla onl f i y e mutatio mutatioa r a deletioo n d an n n occurred (unlikely events). Identificatio f recessivo n e mutationn i s diploid crops usually requires progeny selectio n segregatini n g generations. Similarly a dominant mutation will normally be heterozygou e mutagenizeth n i s d plant which will require selfing to obtain homozygosity. Secondly, because dominan d recessivan t e mutations are expressed in the haploid plant and the resulting doubled haploids, any other mutations inadvertently produced in addition to the mutation of interest in the selected lines will be expressed. Hence, it should be possible to select mutant lines having onle phenotypth y f intereso e t from those lines havin e phenotypth g f intereso e d secondaran t y mutations that may be deleterious. In a mutagenized diploid line, many of the secondary mutations would be recessive, hence masked in many of

11 the selected lines. Selfing the lines with desired phenotype would be necessary to discover these secondary mutations. Also, deleterious recessive allele e losar s t slowly fro a populationm . Combinin n vitri g o selectio r screeninfo n d haploidan g r fo y expressing mutations, will provide powerful methods for mutation breeding. However, a numbether e f drawbackar eo r o usint s g haploid cell culture n cerealsi s . Firstly e ,cereal th man f o y s t havdno o e good cell culture technologies r exampleFo . , anther cultur whean i e s genotypi t e specific (Bulloc , 1982al ; t e kLaza r et al, 1984). While haploid plants of cereals can be obtained throug a numbeh f otheo r r method d coul an s e user expianb d fo d t tissue sources, the cell cultures from these plant tissue are poorly developed. Secondly, haploid cultures often undergo spontaneous doubling (Chalef Rayd an f, 1984; Kudirk1983, al ) t e a thus defeating the purpose of using "haploid" cultures. In this brief discussion, three technologies have been discussed that will be useful in mutation breeding. A question that may be asked, is will they become a dominant technology or replac e existin th som f o e g mutation methods n generalI . e th , methods described here will continue to have major limitations and will be used to solve specific problems in cereals until more is understood about cereal physiology, biochemistry, genome structure, tissue culture, and transformation. Though these techniques are fledgling, significant progress has been made with biochemical selection. However more ,th e classical techniques describe y Konzal b (1984da t e k) have broader usag d wilan el e nearemaith rr futurfo n e morth e e widely used generallan d y more successful mutation breeding tools.

REFERENCES ) KONZAK(1 , C.F., KLILNHOFS ULLRICH, ,A. Induce, E ,S. d mutations in seed-propagated crops, Plant Breeding Reviews (JANICK PublishinI Ed.. ,J AV ) g Company, Westpor 2 (1984t ) 13. (2) BOTSTEIN, D., SHORTLE, D., Strategies and applications of in vitro mutagenesis, Science 229 (1985) 1193. (3) FEDOROFF, N., WESSLER, S., SHURE, M., Isolation of the transposable maize controlling elements Ac and Ds, Cell 3_5 (1983) 235. (4) FEDOROFF, N.V., FURTEK, D.B., NELSON, JR., O.E., Cloning of the bronze locus in maize by a smple and generalizable procedure using the transposable controlling element Activator (AC), Proc. Natl. Acad. Sei. 81 (1984) 3825. (5) BERTRAM, I., ROBERTSON, D.S., PETERSON, P.A., SAEDLAR, H., Molecular cloning of the al_ locus of Zea mays using the transposable element d Mulan , n EMBCT~E s 4 (1985) 877. ) MEYEROWITZ(6 , E.M., PRUITT, R.E., Arabidopsis thaliand an a plant molecular genetics, Science 229 (1985) 1214. (7) FROMM, M. TAYLOR, L.P., WALBOT, V., Expression of genes transferred into monocot and dicot plant cells by electroporation, Proc. Natl. Acad. Sei. 8_2 (1985) 5824. ) DUNCAN , SMITHHeterologou, (8 MOIR, A J. T . . ,D. ,R ,M s protein secretion from yeast, Science 229 (1985) 1219. ) TAYLOR(9 , M.A., JOHNSON, A.D., SMITH, L.Ô77 Growing Xenopus oocytes have spare translational capacity, Proc. Natl. Acad. Sei2 (19858 . ) 6586.

12 (10) LARKIN, P.J., SCOWCROFT, W.R., Somaclonal variation - a novel sourc variabilitof e y from cell culture planfor s t improvement, Theor. Appl. Genet 0 (19816 . ) 197. (11) MEREDITH, C.P., "Selecting better crops from cultured cells", Gene Manipulatio n Plani n t Improvement (GUSTAFSON, J.P., Ed) Plenum Publishing Corporation, New York, (1984) 503. (12) CHALEFF, R.S., RAY, T.B., Herbicide-resistant mutants from tobacco cell cultures, Scienc 3 (198422 e ) 1148. (13) COLLINS, G.B., GENOVESI, A.D., Anther s culturit d an e applicatio o crot n p improvement, "Application f Plano s t Celd Tissuan l e Cultur o Agriculturt e d Industryan e " (TOMES, D.T., ELLIS, B.T .HARVEY, , P.M., KASHA, K.J., PETERSON, R.L., Eds), Univ Guelphf o . , Guelph, (1982. )1 (14) MAHESHWARI, S.C., RASHID TYAGI, ,A. , A.K., Haploids from pollen grains - retrospect and prospect, Amer. J. Bot. 6_9 (1982) 865. (15) BAENZIGER, P.S., KUDIRKA, D.T., SCHAEFFER, G.W., LAZAR, M.D., "The significanc f doubleo e d haploid variation", Gene Manipulation in Plant Improvement (GUSTAFSON, J.P. Ed) Plenum Publishing Corporation Yorw ,Ne k (1984) 385. (16) CHOO, T.M., REINBERG, E., KASHA, K.J., Use of haploids in breeding barley, Plant Breeding Reviews (JANICK, J., Ed.) AVI Publishing Company, Westport, 3 (1985) 219. (17) MEDRANO, H., PRIMO-MILLO, E., Selection of Nicotiana tobacum haploids of high photosynthetic efficiency, Plant Physiol. 79 (1985) 505. (18) BULLOCK, W.P., BAENZIGER, P.S., SCHAEFFER, G.W., BOTTINO, P.J., Anther culture of wheat F1's and their reciprocal crosses, Theor. Appl. Genet. 6_2 (1982) 155. (19) LAZAR, M.D., SCHAEFFER, G.W., BAENZIGER, P.S., Combining abilitie d heretabilitan s f calluo y s formatio d plantlean n t regeneration in wheat (Triticum aestivum L.) anther cultures, Theor. Appl. Genet 8 (19846 . ) 131. (20) KUDIRKA, D.T., SCHAEFFER, G.W., BAENZIGER, P.S., cytogenetic characteristic wheaf o s t plant regenerated from anther calli of 'Centurk1, Can. J. Genet. Cytol. 25 (1983) 513.

13 ACTIVIT INSTITUTE TH F YO EXPERIMENTAF EO L RESEARC CEREAR HFO L CROPS, ROME

A. BIANCHI Istituto Sperimental Cerealicolturaa l r epe , Rome, Italy

Abstract

The achievements of the Institute) Gporimontaio per la Ceroa M en 1t ura e ar briofly summari/o o h presentel n i d d papor. Betweee horl th nn semi dwarf wheat varieties bred by this Institute like ftrolito, V i lia Glori, Montana r duru,fo Damianod m an spocip ia l ll Ba , s Geria e Cappellitor . The present main activity of the Institute is devoted to the deslqn of experiments, applied qonetics, agronomic techniques and technology of cereal prtxlu. s ct

This institut s name wa e eInstitut th d f Genetico e f Cereals o s it y b s founder Nazareno Strampelli n 196i e nam s e d changeth 8wa th ean , o t d above facIn .t Nazareno Strampelli realize firsthe d t Green Revolutioin n the 1920's, this means after two decades of his first cross breeding activities. He put to work Mendel's laws exactly at the time when they were rediscovere y usinb d g recombinatio r breedinfo n g purposes. Indeed, e crosseh e wheath d t varietied Riet an n ordei ié o combint No rs e th e resistance to lodging of the former with the resistance to rust of the e reminiscencth later t e geniuBu th . f f Strampello o se s specificalli i y appropriat e contexth n f i ethio t s meetin n connectioi g f o e nus wits hi h the short Japanese variety Akagomughi, very early f ,o poo evef ri n agronomic value, unde conditionsour r . Strampell 190 in icrosse 6had the d Italian variety Rieti with Dutch Wilhelmine Tarwe, obtaining a type with high yielding potential t verbu , y late n 191I . 3 this crossewa s d with Akagomugh d froe segregatinan ith m g generation n 1920e i famou, th , s Ardito variet s obtainedwa y . This variety matured 15-20 days earlier thae th n other contemporary varieties and was resistant to lodging because of its height, only 80 cm. By its high yield Ardito gave a first, clear demonstration that it was not an alternative to earliness. The spreading f o Ardito into Italian agriculture induced also several indirect benefits. A harvest of wheat 2-3 weeks earlier than usual allowed a reasonably advantageous secon e dsam th ecro n o fieldp . This allowed peopl o escapt e e advancinth e g worst phas f mosquito e o populatione th n i s areas afflicted with malaria e resistancTh . o lodgint e g allowed farmers e mortus oe fertilize d consequentlan r y additional yiel s gainea wa d s a d resul f thio t s improvement.

In a few years other successful Stampelli varieties invaded Italy. There were well known early varieties Villa Glori, Mentana, Damiano and e earliestth , Balilla. Amon e latth ge type s spreawa s d Virgilir fo d an o durum species Senatore Cappelli (still largely cultivated and still one of the besr quality)fo t e las Th f Strampelli'o .t s achievemente th s wa s variet . PastoreS y a wel, l known bread wheat very successfu n Itali ld an y many other countrie morr fo se tha 0 years4 n .

15 e IstitulTh o Sperimental a Cerealicolturl r pe e a carrie i studieou s s and research dealing with cereal genetics, breeding of wheat, maize, rice and minor cereals as well as with agronomic techniques of cultivation of these cereals. This Experimental Institut r Cereafo e l Research succeeds with its activity and to a large extent with its properties in general, to institutions e workinfielth f o cerean di g l research, especialln i y aspect f o geneticss , agronom d technologyan y e ,NationaTh sucs a h l Institut f Genetico e r Cereafo s l Researc . Strampelli""N h , Romee th ; Experimental Station for Wheat Research, Rieti; the Plant Breeding Institute, Bologna; the Experimental Station for Maize Research, Bergamo; and the Experimental Station for Rice Research and Irrigated Crops, Vercelli, where great breeders such as Strampelli, Todaro, Zapparoli, Novell d Bonvicinan i i have been e fielactiv th f plan o n d i e t improvement. e InstitutTh e consist f fouo s r centra d sevean l n peripheral sections plus the Morando Bolognini Foundation. The central sections are devoted to: design of experiments; applied genetics; agronomic techniques; and technolog f cereao y l products e peripheraTh . l section e specializear s s a d follows: Vercelli, in genetic improvement and agronomic techniques of rice . AngelS ; o Lodigiano (Milan), genetic improvemen f wheao td ryean t ; Bergamo, genetic improvemen d agronomian t c technique f o maizd s an e sorghum; Badia Polesine (Rovigo) and Fiorenzuola d'Arda (Piacenza), genetic improvemen d agronomian t c technique f cereao s l crops; Foggia, genetic improvemen d agronomian t c technique f wheato s , barley, sorghum, oat and maize; Catania, genetic improvement and agronomic techniques of wheat, barley and sorghum.

Bread wheat is considered the most important cereal crop in Italy, and it has held this position for the last centuries. During the last few years its area has been surpassed by duriyu wheat. At present the bread wheat are s aboui a t 1.400.00 , beinh 0 e areg n th whico hala f o fh bread wheat was grown a few decades ago. The reduction is the consequence of the relatively scarce economic competitivenes e yiel d th qualit an f do s f o y Italian bread wheat e nationath : l yiel s beloi d 4 t/haw , this means below the leve f averago l e yiel f o severad l European countries e breaTh . d making quality is not the best, and Italy is forced to import bread wheat from North America r thiFo .s reason e Institutth , e choso maitw e n breeding objectives o improvt : e qualit th ea relativel n i y y short time, which appears the most realistic goal. Even small improvements of quality can solv e problemth e , considering thar practicafo t l purpose a mixturs e f flouro s utilizedi s t appearI . s tha t wil i te difficul b l o obtait t n varieties with high yiel n Italyi d , similae leveth n Centra i o lt r l Europe and England, because of the unfavourable growing conditions in most areas. The very high temperature in June, together with the usual lack of rain, e accountverth y r earlfo s y e wheaendinth tf o gplan t cycler Fo . this reason, since Strampelli's time, the breeding for earliness is the second important objective of our Institute. The irrigation of cereals doet appeano s r promising unde r conditionou r e absolutth f i s e th cos f o t operatio f o wate r s considered othei e fo nr us r e crop Th s mori .s e profitable. Under these circumstances we believe that hybrid plants can be another possibility for our conditions. The physiology, resistance to disease as well as to other stresses are the main topics of experimental activity to cope with the difficult task presented.

As mentioned, during the last few years, durum wheat has become the largest cultivated crop of Italy, with an area of about 1.600,000 ha. This cros significantli p y favoure y Europeab d n Community policyt A . present the greatest producers are Italy and Greece. However, the yield is lower than bread wheat and the national average is higher than 2.5 t/ha

16 only in very favourable years. Great handicaps for better results are: poor rainfall, concentrated in the winter months; dry winds in May and June that cause early maturing of the plant associated with severe shrivellin f kernelso g e yelloth ; w berry; sensitivit o rustst y , milded an w Fusari urn. Durin e paso decadeth gtw t s durum whea s greatlha t y increased total production thanks to new higher yielding varieties such as those bred by ENEA. Other breeding activities of this Institute, made possible the expansio f duruo n m cultivatio n Centrai n d Northeran l n Italy wherw ne e genotypes with cold resistance finall d well di s everyonyA . e knowse on , e mosth t f o important destination f dujrjao s m grai n thii n s countrs i y pasta making with special emphasis on spagetti. The quality of Italian products in this sector is well known and the increase of pasta consumption worldwide is largely accredited to the successful export of Italian specialities r thiFo .s reaso e improvementh n f duruo t m wheat qualits i y imperativ r Italiafo e n breedin d thian gs Institute make o exceptionn s . Even if some industries assert that with modern technology it is possible o obtait a goon d qualit f pastao y e Institutth , e stresse e importancth s e of the quality improvement of durum grain for nutritional as well as for technological reasons. The situation will become more critical when several countries of Central Europe should begin or expand their durum area cultivation n thiT . s respec t shouli t e mentioneb d d tha n spiti t f o e the fact that Italy is exporter of durum wheat products, the import of durum grain is necessary not only in years of scarce production but also to meet external demands for products from Italy's specialized industry, considered one of the best in this specific sector.

Maize, als oe acreagth thir n i de lisr Italiafo t n cereals, wits it h 1,000,000 hectares, supplies the highest number of calories, as a consequenc s verit y f o hige h average yiel f abouo d 7 t/ht a (no to mentiot n n additionao l 350,00 a cultivateh 0 s silaga d e crop) n NotherI . n Italy ther e provincear e s with yield f oveo s 8 t/hr d farmaan s that conside0 1 r a norma t/hs a a l result. However e problemth , e numerouar s s also under such circumstances. The cost of maize grain production under Italian conditions, e witreduceth h d siz f o farme , artificial irrigatiod an n chemica d mechanicaan l l input s unbearabli , r yieldfo e s belo a wgive n level. This is the reason for which the Institute co-ordinates a programm f co-operativo e e trials wite besth ht hybrids developee th y b d main seed companies. In this context the specific contribution of the Institute to maize improvement is mainly the breeding via improvement of hybrid components n Southeri d an , n Italy, analysi f irrigatioo s n aspects. Nevertheless, the study of genetic basis of protein quality, breeding of valid opaque lines, chemical expressio f o glossn y genotypen i s epicuticular wax, and the analysis of controlling elements through genetic, in-vitr d moleculaan o r experiments e othear , r e topicth f o s Institute's activities.

e fourtTh h cerea f o Italial n agricultur s barleyi e e ared th ,an a yield of which has grown continuously and significantly during the last 20 years. During this perio e are th f dcultivatioo a s doublewa n d totaan d l productio s quadruplewa n e samth en i periodd . This beeha sn caused mainly e growinth by g reques r foddefo t r barley. Such increas n i barlee y productio s chieflwa n y possibl y b introducine g high yielding varieties bre n centrai d l Europe. However e spreadinth , f similao g r genotypea n o s large scale in several regions of North Italy was soon followed by parallel spreadin f seriouo g s epidemics e verTh y. poor lodging resistance of introduced varieties under Italian conditions was connected with these varieties as well. This situation has promoted a programme which has led to the first promising results in breeding varieties for Northern Italy.

17 New types of barley are also developed for Southern Italy where barley is also an important crop in many hilly areas. This activity was developed on the basis of studies on irrigation and drought stress problems which r e thicarriefo ar st regionou d .

e facn spitth I tf o etha t ric s cultivatei e d onl n abouo y t 200,00a 0h n a importan s i td interestinan t g cro n Ital i r psevera fo y l regions: Italy is by far the largest producer of rice in the European Community. More than 50% of the production is exported mainly to the Common Market countries e cultivatioTh . s concentratei n w provincefe a n f i Norto ds h Italy, mainly, between the cities of Turin and Milan, but also in o ValledistrictP e th yn Sardini i f neao e sAdriatid th ran aa wherSe c e th e dry conditions favour a superb seed production. Because of the special climatic conditions provide e Alpd Appeninesth an s y b d o ValleyP , , with its mor f o Norte ° thah 45 ne latitudlargesth s i te aref o rica e cultivatio n similai n r geographical locations. Mountain chains protect the rice cultivation area from critical transpiration and fall of temperature durin e night th e gproblem Th . s with whic e havw ho copt e e ar e various: earliness coupled with yield in connection with the specific pedoclimatic situation, resistanc o diseaset e d lodgingan s , pollutiof o n irrigation wated completelan r y mechanized monocultures. Under such condition e surprisint shoulb i s t no d o leart g n that althoug e yielth hs i d e highese worlth th f n o di t e (5.5-on 6 t/h f apaddo y cropss changeha t i ) d slightl s comparea y o othet d r crops wher e productivitth e s morha y e than doubled since World War II. On the other hand the hours of work that were neede o obtait d a quintan f produco l t have decreased manifold 5 hour4 . s f wor o s estimatei k t presena d o product t 6 t/he a while on 0 year3 eo ag s hectare needed abou 0 wor70 t k hours wit a productioh 5 tons5. f .o n

e breedinTh d agrotechnicaan g l activit s orientei y o keet e dcos th p t f productioo a minimur uni o pe nt t mo improvt leve d an le grain quality. The so called j_§P_o!lÀ-Çâ type is preferred for internal consumption of rice whereas indj._c_a type has preference for export to most markets. For various reasons the indica type of rice in Italy is less productive.

Other cereals cultivated in Italy are oat, rye and sorghum; whereas e firso th croptw t s have unfortunately scarcely bee a subjecn f o t systematic experimental activity, sorghu a subjec s i m f muco t h researcn i h several institutes. Investigations are concentrated on the improvement of adaptability, agronomic techniques, quality improvement with special emphasis on tannin content of grain to upgrade socalled "bird resistance" while retaining the nutritional value for use in animal feeding.

e InstitutTh e closely collaborates e witMorandth h o Bolognini Foundation. This Institution is responsible for multiplication of seeds f newlo y developed varietie d distributioan s o seet n d companies t onlno , y in Italy but in various countries as well. The promotion of new, improved genotypes as appears from promising results of maize lines and cultivars f o whead barlean t y recently released s anothei , r activit f o thiy s foundation.

18 GENE MANIPULATION BY MUTATION TECHNIQUES

M. MALUSZYNSKI, B. SIGURBJÖRNSSON, A. MICKE Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna

Abstract

e mosTh t important result f cereao s l mutation breedin e presentear g d as examples of the usefulness of techniques for crop improvement. These economically valuable results were obtained with very limited input. It was demonstrated that the mutation method, in comparison to conventional plant breeding, involved only a small number of breeders with limited facilitie d financiaan s l support e introductioTh . f o biotechnologn y methods in plant breeding provided an opportunity for wider implementation f mutanto mutatiod an s n techniques.

Many terms are used in relation to biotechnology. Recent advances in recombinant-DNA technology or more general, in genetic engineering, fully justify a very wide definition: Biotechnology includes the utilization of a biological system or process of microbial, plant or animal cells and their constituents in organized human activities. Laskin (1983) clarified a simplthi n i n sa integrate e s manneri t "i d: multi-disciplinary field that utilizes many different technologies and impacts on a wide variety of areas". In his opinion the core disciplines of biotechnology aro micro- biology, biochemistry, enzymology and molecular genetics. This core is surrounde y sucb d h discipline s moleculaa s d celan r l biology, immunology, organic chemistry and the applied sciences of agricultural and food technology. Although industries are increasingly utilizing biotechnological processes, agriculture is without a doubt one of the most important impact areas for biotechnology.

Simmonds (1983) discussed the complicated relationships between basic research, some areas of agricultural biotechnology and plant breeding. An interdisciplinary approach to plant breeding includes such fundamental discipline s a cytogeneticss , chemistry, biomolecular chemistry, plant physiology, cellular physiolog f courseo d an y, genetic engineering. These disciplines, together with other methods of biotechnology help solve the main task of plant breeding: gene manipulation for crop improvement. The main aspects involved in this area of biotechnology are: embryo-culture, shoot tip culture, clonal multiplication, disease resistance, genetic resource conservation, somaclonal variation, haploids, mutation induction, stress selection, in-vitro hybridization and industrial products.

w combinationNe e createb f geneo sn y ca crossinb sd o parentw g t plants possessing gene sets capable of improving desirable characters in the progeny. The main problem of this conventional breeding technique evolves froe paralleth m l transfer froe genotypon m o anothet e r unwanted gene(s). The required generations of backcrossing drastically decrease the efficiency of this gene manipulation technique. Nevertheless, during e verth y long histor f thio y s method, many spectacular successes were obtained and cross breeding is now practically the main way to improve

19 germplas f currentlo m y cultivated varieties. Such spectacular success using cross breeding technique s observee wa improvemens th n i d f rico t e cultivars. The breeding programme of one of the developing countries could be used as an example, but similar conclusions can be drawn if highly industrialized countries are taken into consideration.

In Japan the story of rice cultivar improvement can be described as follows. The average yield has increased from 3.0 t/ha in 1955 to about e 60' th e tur s f th a o breakthrougn ther 1979 i t s A 0 .wa e 5. h5 fro0. a m millio n shortagto n f ric o eo overproductio t e f abouo n 1 milliot n tons. Parallel to these changes there was an increased tendency toward mechani- zation in rice cultivation in the early 70's. Harvesting machines were used - 27% in 1970, 59% in 1973, 87% in 1976 and 95% in 1979 (Sato and Kaneda, 1981) t shoulI . e noteb d d tha a different t typ f rico e e plant architecture and physiology (stiff, lodging resistant straw) is needed for mechanical harvesting e introductioTh . w mechanicane f o n l techniquen i s rice cultivatio s mainlwa n y possible e becausdevelopmenth w f o ne e f o t types of rice varieties which directly initiated the "Green Revolution" in Asid othean a r regione worldth f o .s

Two main characters limiting rice yield, particularly in good agro-ecological conditions are: lodging (caused by long, weak straw) and low response to nitrogen fertilization (Fig. 1). It should be noted that t onllodginno y n decreasca g e grain yield d makan se mechanized harvest more difficult but can as well reduce the grain quality. These problems will increase drastically wit a significanh f o e tus e increasth f o e fertilizer. It was feasible to solve this technological problem by rather simple gene manipulations. The transfer of desirable genes was possible in this case because of the existance of the Dee-geo-woo-gen (DGWG) in a Chinese variety. This gene manipulation was done by its introduction to a genotyp e talth l f locao e l Taiwanese variety, Tsai-yuan-chung. This cross resulte e releasth n n Taiwai i de n e semi-dwar(1956th f o ) f rice variety

Grain yield (kg/ha)

9,000 -

8,000 -

7.000 -

Nitrogen applied (kg/ha)

Figure 1: Nitrogen response of Peta and 1RS during 1966 dry seaso t IRRa n I (after Khush, 1984)

20 Taichung Nativ 1 (TNl)e . Thiw varietne s y a typparens use s wa ea n d i t many crosse n differeni s t countries a resul s A f anotheo .t r transfef o r e semi-dwarfnesth s gene fro mn Indonesia a DGW o t G n tall indica variety Peta in 1966, a new semi-dwarf variety 1RS was developed. The cross was made at the International Rice Research Institute and this variety, together s witdescendantsit h , brough e "Greeth t n Revolution o mant " y countries in the tropical zone of Asia (Khush, 1984).

A gene similar to DGWG was found in a native, semi-dwarf japonica type, variety Jikkoku. Three new, high-yielding varieties (Hoyoku, Kokumasari, Shirani) were release n southeri d ne earlJapath n yi n I960*s as a result of transfer of this character by crossing with variety Zensho 26 (Kikuchi and Ikehashi, 1983).

Another approac o manipulatiot h f gene(so n ) responsibl r semfo e i dwarf characte s demonstratewa r y Futsuharb d t al.e ad an , (1967)R k 0 2 . R gammk 0 a3 rays fro a ^0m Co sourcc were user irradiatiofo d 195n i n f o 9 2500 dry seeds of a promising line, Fukei No. 47, later known as variety Fujiminori e frequencTh . f short-culo y m plants detectee seconth n i dd generation (about 50,000 plants) after treatment was relatively high and reached a value between 4.3 - 9.5%. Of the 112 observed plants only 46 were selecte r observatiofo d f thio n s characte e nexth tn i progenyr . Most f o these selected plants gave true breedin 3 progeny¥ ge th line .n i s This presented an opportunity to evaluate of their yield capability. From 13 lines chosen for M4 progeny, 4 have shown higher yields than the parent variety.

Two promising lines (Fukei No. 70 and Fukei No. 71) selected the fourth year after mutagenic treatment, practically completed the breeding procedure. During three year performance trials test Fukei No. 70 was recognized as being more suitable for the northeastern part of Japan and s officiallwa y w varietreleasene a s ya d named Reime n 196i i 6 (Futsuhara, 1968). Reime s cultivatewa i d over wide areas durin e earlth g y 1970's, ranging from 3rd-5th place, and helped to overcome the shortage of rice in Japan - due to its lodging resistance and high yielding ability. Because of these characters Reimei was used as well in cross breeding programmes a resul ans e varieta dth t y Akihikari (Nori . 238No ns releasewa ) n i d 1976. Since 1979 it has ranked 4th or 5th on the list of planted rice varietie n Japai s n wit a cultivateh d are f abouo a t 120,00 . Thiha 0 s variety (Toyonishiki x Reimei) inherited both of the most important character f Reimeio s : resistanc o t lodgine g with high utilizatiof o n nitrogenous fertilizer and high yield.

Eradication of the rice deficit by introducing high yielding varieties, together with a declining tendency in rice consumption, has drastically decrease s cultivateit d d areae 196 n th 198I .5f o 1 onl% 79 y e 196th lowlan 9f o uplan% d22 ared an afield s were cultivated with rice (Sato and Kaneda, 1981).

The importance of mutation techniques as a tool for gene manipulation in modern plant breeding can be demonstrated using rice production in the USA as an example. This country's contribution to the total world production is only 1.6%, or 6.2 million tons with an average yield of about 5 t/ha. This average yield placed the USA in the 6th position in the world - after Oceanic region (6.3 t/ha), Japan (5.8 t/ha), South Korea (5.7 t/ha), North Korea (5.6 t/ha) and North Africa region (5.6 t/ha). This high production, together with comparativel w riclo ye consumptionf o , yiel e world'th d s i accounte facs th A largest US r thafo e s th t exporter f riceo .

21 The average yield of rice cultures in California is about 50% higher e otheth tha n ri nrice-producin g e USAstateth .n i sBasically a cold, - tolerant japonica type of rice with short to medium grain is grown. This n contrasi e ssouther th o t S twher U n e more indic r indica/japonico a a type with long-grai e cultivatedar n e productioTh . e th f o ricn i e temperate e climatSacramentth f o e o e Valleth n f Californii o y e on s i a most highly sophisticated agricultural battlee worlth - usinn di s g laser beams for precise levelling of rice fields, airplanes to sow seeds and dispense granular herbicides and special combines that will not bog down in mud. Under these condition e averagth s e yiel n Californii d n 197i a 9 was 50% higher than the average in the other states, reaching about 7.2 t/ha (Rutge Brandond an r , 1981).

To properly evaluate the excellent results of plant breeding and other agricultural science t shouli s e noteb d d that rice becam a come - mercial crop in California only about 1912. Plant breeders and geneticists d establisheha a programmd r consequenfo e t improvemen f rico t e cultivars. The breeding objective, similar to the Japanese one, was defined as follows o develot : p short-stature type f rico s e plants which wile b l highly resistant to lodging or falling over, especially during maturity time. Currently available method f o gens e manipulation were useo t d realize this task. Lodging resistant varieties with high responso t e nitrogen fertilization were developed by mutations, hybridization and by immediate integration of induced mutants into hybridization programmes. McKenzi d Rutgean e r (1984) report that since 1970 9 ,commercia1 l rice cultivars were released in California. Three of them were directly selected induced mutants and seven were recombinants from crosses where mutants were used as parents. This success in utilizing mutation techniques in California has a short history. Calrose, (released in 1948), tall (120-130 cm), medium-grain variet s irradiatewa 5 y2 d an dR k wit 0 2 h kR gamma rays from 60Co at the University of California in 1969. Only 2,050 seeds were user eacfo dh dose n 1972I . , after selectio n earli n y progenies 1 mor1 , e promising mutants were investigate a small-plo n i d t replicate ^ generatioM d n yield trial.

Alread n 197i y 4 three short-stature mutant sd D24an (D7 1 ), D5 were included in multi-location, large-plot yield trials in California. In 1976 the mutant D7 was registered as a new variety "Calrose 76" (Reg. No. 45). Calros s similae pareni th 6 7 o et tr variet % plany25 excepa t r fo t height reduction. Durin 3 yearg f observatioo s s averagit n e mature height was 87 cm. but most important, the panicle length remained unchanged. Paralle o testint l g procedure f selecteo s d mutant r agronomicafo s l characters, two of them (mutants D7 and D51) were used as parents for hybridization with Calrose and a tall check cultivar CS-M3 already in 1972. (Rutge t al.e r , 197 d Rutge6an t al.e r , 1977). Immediate transfee th f o r induced semi-dwarfness gene to another genotype of cultivated varieties gavx additionasi e l cultivar e yearth n si s 1977-81. This possiblewa s , because of the collaboration of Dr. Rutger's team at the University of California wite Californith h a Co-operative Rice Research Foundation Inc. at Biggs n 1981I . 2 year1 , s after irradiatio d varietol e f seedo th ny f o s Calrose, 7 new varieties with the Calrose 76 gene of semi-dwarfness were cultivate e 245,00th f o a ricn h 0abou o d% e 59 tare n Californiai a w Ne . semi-dwarf varieties s indicatea , y cumulativb d e evidence, brough a yielt d n increasfarmi d s an f abouwit o e% 15 ht intensified cultural practicef o s about 25% This means about 1 metric ton more per hectare in comparison to California's 6 metric ton/ha base yield level (Rutger, 1983). This is an example of the economic importance of this method. Rutger's work demonstrates that mutation techniques provided a promising opportunity for

22 CI 11046 Q 11049 Short I 1104C 5 (M5) (Colrose) Labelle (M5) \ / (Lobelle)

Calrose76(Calrose) ail035(Cotuso) M-40l(Terso) DGWG

CI 11034 023 5U« *"* CI II033 025 —————————————————(caisse) (Colrose)

Figure 2 Allelic relationships of induced semi-dwarf mutants and DGWG Gentotypes of the same corner of the triangle are allelic* thos t differena e t corner e nonalleliar s c Genotypee th n i s "fan1 at top are nonallelic to the sd locus but their relationship o othet s r loce unknowar i n Parent cultivars are show n bracketi n s (afte r, 1985 Rutgel a )t e r

plant genetic engineering. His team found that semi dwarfness can be induced in several indépendant, non allelic loci (Fig. 2). The allelism tes f differeno t t semi-dwarf mutants brough e unexpecteon t d result that tall plant type can be inherited recessively to semi-dwarfs The "elongated uppermost internode" gene (eui) result n extremi s e elongation of the first internode under the panicle. This mutant can help in productio f hybrio n d seeds which will resul^ plantF n i ts with heterosis e transferreb effeci genn eu n ca yield eo te o Th pollet d. n fertility restoring parents, which woul e especiallb d y useful whe a semn i dwarf type ! F plant f s wantedo i se talTh .l plant s donoa , a f polleo r r fo n cytoplasmic male sterile parent, a morwil e eb l effective pollinator whic s extremeli h y importan e d pricfinallth an f o r r eseet fo fo tse y d hybrid seeds (Rutge t al.e r , 1985).

e onlth y t examplno Ric s i e e among cereal r successfufo s l man!pu latio f o genen y mutatiob s n techniques e technologTh . r breedinfo y g barley with shorter straw was developed in England during the last 80 years. Released in 1900, the spring barley variety Plumage reached a final plant height of about 112 cm. Triumph, released in 1980, grows only up to 70 cm. Together with this tendency to decreasing plant height, it is possibl o observt e e increasth e f yielo e d capabilitys A (Fig . 3) . presented in the cited paper (Riggs et al., 1981) data from plants with a high level of nitrogen fertilization and support treatments for all considered varieties gav n excellena e t opportunit o compart y e yielth e d potential between old-tall and modern-short stature spring barley varieties. In a more drastic case, the yield difference is about 2 t/ha (Chevalier 6.46 t/hd Egmontan a , Korn, Triumph with mean yields 8.45 t/ha) in these same preferable growth conditions.

23 120

O -C o

C 20 30 40 50 60 70 80 90 100 '880 1900 1930 1950 1960 1970 1980 YEAR Figur : 3 Yiele d potentia f sprino l g barley varieties released during the last 100 years in UK in relation to final plant height (from data presented by Riggs et al., 1981)

8 sprin e th g f barleO y varietie w grow no sn Englan i n d Walesan d 3 , are semi-dwarf mutant varieties. On the basis of data on seed multiplication area presente y Lidgatb d e (1982s possibli t i ) o calculatt e e that 41.6% is covered by mutant varieties, which allows us to presume that these varieties are cultivated on about 450,000 ha in this region of the UK.

The breeding objective of plant breeders in Czechoslovakia was to obtain spring barley with shorter and stiffer straw. Seeds of the old Moravian land variety Valticky were irradiated with 10 krad in 1956. Nine years later the mutant line VR2 was registered as a new Czechoslovakian improved variety under the name Diamant (FAO/1AEA MBNL, 1976). After a w yearfe t becami s e leadinth e g barley varietl regional n f Czechoi o ys - slovakia. This variety, whic s weli h l adapte r Czechoslovakiafo d n agro- climatic conditions with good grain malting quality s beeha ,n a use s a d popular parent variet r differenfo y t cross-breeding programmes. Altogether 11 varieties (progenies of crosses with Diamant) were released - not only in Czechoslovakia but in neighbouring countries such as the DDR, USSR and Poland as well. More than 96% of the spring barley areas in Czechoslovakia e sowar n with varietie e "Diamanth f o s t series" (Bouma, personal communication). Trumph, one of these varieties released in the DDR in 1973, is cultivate n thii d s countre n Polanbesi th td s a an dbrewery y spring barley and moreover is utilized as parent variety in new breeding programmes.

These economically valuabl f mutatioo e eus resultne techniqueth f o s s were obtained with very limited input n comparisoI . o conventionat n l plant breeding e mutatioth , n method usually involved onl a smaly l number of scientific teams with limited facilities and financial support. It shoul e considereb d e mutandth thal tal t varieties presented above were selected in the second generation after mutation treatment as individual

24 plants fro a comparativelm y small populatio f abouo n t 50,000 plants.This successful selectio f cerealo na 2,00 s n carrie^ o experiwa m 0s t ou d- mental field. The scale of this activity is practically uncomparable to any other plant breeding programme. It should be noted for example, that the British Association of Plant Breeders estimated the number of £'2 cereal plant se breedingrowth n i n g programm n 198i K 0s U ea e fieldth n i s close to 10 million (Foster, 1982). Very high efficiency must have led to e recenth t successe f geno s e manipulation using induced mutations.

The International Atomic Energy Agency, jointly with FAO, has supported activity on the use of the above discussed techniques in many countries around the world. The Green Revolution flourished due to introduction of short statured varieties of rice and wheat with high response o nitrogenout s fertilization, thus solving many problem f fooo s d suppln i y developing countries. Nevertheless, it should be considered that modern rice varieties, for example, cover about 42% of the rice area in 11 countries of Asia (Pinstrup-Andersen and Hazell, 1985). The rest is still cultivated by traditional local varieties which very often represent a special valu r inhabitantfo e f thio s s are e acookin Th (Tabl . g1) equalit y or the specific aroma are usually the most important characters prefered r thiy peoplfo b sd reasoan e n traditional varietie sn compet i ofte n wi n- ition with modern varietie n locao s l markets, even though their yield potential is much lower.

Table 1: Area Grown with Modern Rice Varieties in 11 Asian Countries

Country Year 1000 ha Rice Area

Bangladesh 1981 2,325 22 India 1980 18,495 47 Nepal 1981 326 26 Pakistan 1978 1,015 50 Sri Lanka 1980 612 71 Burma 1980 1,502 29 Indonesia 1980 5,416 60 Malaysia W 1977 316 44 Philippines 1980 2,710 78 Thailand 1979 800 9 South Korea 1981 321 26

(after Pinstrup-Anderse Hazelld an n , 1985)

The genetic constitution of these local varieties can usually be improve o maitw y nchanginr b do character e on g s limiting their yield capacity. This shoul e dony b thadn e genetisuc wa i eth t a h c background responsible for their valuable traits is left unchanged. In this case the manipulation of genes by cross breeding is very difficult and time consuming. Mutation techniques offer a simple and efficient solution.

25 Ther e manar ey example f successfuo s f mutageno e r us improvemenl fo s f o t rice cultivars (Mick t al.e e , 1985), e.g.:

India: variety Jagannath, release n 1969i d , after x-ray f o plans t variety T141, direct selection in M2 progeny. Important traits: medium slender grain, good cooking quality s growi t nI . in lowland coastal areas of peninsular India with a yield of 6-7 t/ha.

Pakistan: variety Kashmir Basmati, released in 1977, after gamma rays of aromatic variety Basmati 370. Important traits: early maturity, higher yield potential, aromatic. It is cultivated in Northern area f o Pakistas n (Azad Kashmir n a altitud t a f )o aboue t 560-140 0m abov a levelse e .

Thailand: variety RD6, release n i 1977d , after gamma irradiatiof o n variety Khao Dawk Mali 105. Important traits: glutinous endosperm and improved blast resistance, very popular in the northern par f Thailando t .

Japan: variety Miyuki-mochi, release n 1979i d , after gamma irradiation f o parent variety Toyonishiki. Important traits: glutinous endosperm, other characters same as parent. It is locally distribute Nakann i d o prefecture, Central Japan.

China: variety Yuan Fengzao, released 1975, after gamma irradiation of parent variety Kezi No. 6. Important traits: 45 days earlier, yield 10% higher than local commercial variety, 8-14% higher lysine content. It is cultivated on about 1 million ha.

GENE TRANSFORMATION y genesCLONIN(b , chromosomesG , DNA)

ANTHER CULTURE PROTOPlAST FUSION MODIFIED POLLEN CULTURE SINGLE ORGANELt E TRANSFER CELL n/2n/4n

BIOCHEMICAL MUTATION SELECTION

HAPLOIDS GENETICS (by crossing)

PLANT BREEDING PROGRAMMES

IMPROVED VARIETIES

Fig New inputs to plant breeding (Bright et »l,/ 1982)

26 It was possible as well to solve some biotechnological problems of beer production by using induced mutagenesis. The precipitation of polyphenols is the reason for the so-called chill haze. Proanthocyanidins of barley are considered a main source of the polyphenols in beer. To obtain colloidal stabilit d brilliancan y s necessar i f o bee et i r o t y remov e polyphenolth e y b chemicas l treatment. n Wettsteis Vo hi d an n co-workers already solved this problem. After mutagenic treatmenf o t sprin d wintean g r barley they obtained many mutants fre f proanthoo e - cyanidines. The mutation frequency of mutants with this character average plant-basi- 2 sM 0.003n a t reachen o %bu s d e variet0.011th n i %y k Royal Ar 6 mutant11 . f sprino s f winteo g 1 1 barler d barlean y y were found (Larsen, 1981) t shoulI . e emphasizeb d d that beer brewed from proanthocyanadin-free mutant d gooha s d qualit d brilliancan y e stability withou y chemicaan t l treatment.

Cereal improvemen n exampl e a abovs use th wa s t a den i edeliberation s on the possibilities of gene manipulations by induced mutation for two reasons e firsTh . t s becausimportancit e worl f th o e dr fo fooe d supply e seconanth d d becaus n suci e h specie s rica sr barleo e y conventional breeding is so sophisticated and has such a high rate of success that special techniques are needed to give superior results. For the last reason more examples were taken from developed countries where plant breedin n extremela n s carrieo i g t you d high standard e resultTh . f o s crop improvement by the use of mutation techniques were recently summarized in other papers (Kawai, 1983; Sigurbjb'rnsson, 1983; Konzak, 1984; Mick t al.e e , 1987).

e introductioTh f biotechnologo n y method o plant s t breeding provide opportunity for wider implementation of mutants and mutation techniques.

Plants regenerated fro n vitri m o culture y diffesma r froe originath m l in many characters. This kin f variatioo d s knowi n s "somaclonaa n l variation". Different variants obtained in this way can potentially be utilizew genetine s a cd source r crofo s p improvement. Unfortunately, regeneratio f planto n s from isolated cell f commoo s n growing cereals ha s so far been unsuccessful. But even in the future - after such promising technique s gena s e manipulatio y protoplasb n t fusio e availablar n r fo e wheat, ric r barlee o interese th - y tn transferin i wil e b l g onl a smaly l part of the donor genome to the improved genotype. Theoretically this partial genome transfer can be carried out with the help of fragmentation of the donor genome by radiation. The efficiency of this method is already evaluate f potato e dus o wite protoplasth h t culture where plant regeneratio possibls i n e (Jone t al.e s , 1984).

Doubled haploids (DH) methods became more readily availabl n cereai e l breeding after improvement and development of general methods. The main breeding advantage f o thess e technique e rapiar s d shortenine th f o g breeding cycle, need for derivation of homozygous lines and new possibility of selection for desired characters in the absence of dominant variation in the genotype. Swaminathan (1984) recognized these tech- e firsnique th f man o ts a sy genetic engineering techniques whic y offema h r w way ne o improvt s e cultivar yields e calculateH . d "th H techniquD e e reduced the time needed to get a new variety from 10 generations with conventional breedin s threa w ge fe methodgenerations" s a o t s .

27 The other advantages in using doubled haploids were discussed by Baenzige d Schaeffean r r e haploi(1984)th n I d. level, selectioe b n ca n made not only for dominant but for recessive genes as well. Doubling of selected haploid genotypes, changed previously by mutagens, makes possible e agrobotanicath l evaluatio e nexth tf o progenn a plo n to e y basith n i s field trials. Such practically homozygous progeny makes selection more efficient by decreasing the time needed for genetic stabilization of evaluated stocks.

Mutation techniques (gamma irradiation) can be used as well for stimulation of callus initiation and shoot differentiation in wheat in-vitro culture (Gao Mingwei et al., 1985).

Mutation technique e useb n d ca swit h succes^ hybriF n i sd cereal programmes. Simila o resultt r s obtaine n sugao d r beet (Kinoshit t al.e a , 1982), mutagens can be used for induction of cytoplasmic sterility or for male sterility genes in cereals as well (Foster and Fothergill, 1982). Mutants of crop plants can be produced on F^ hybrid plants with high vigo d higan r h yield potentia n crossei l s with other mutant r eveo e s th n parent variety. These phenomenons were observe n sweei d t clover (Micke, 1976), barley (Maluszynski, 1982) and recently in maize (Dollinger, 1985). Results published in these papers indicated the next possibility r genfo e manipulation.

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28 O MINGWElCA , LAING ZHUGING, CHENG XIONGY1NG, (1985) "Effec f gamma-rao t y treatment of wheat somatic tissue culture", In: Symposium on Plant Breeding by Inducing Mutation and In vitro Biotechniques, October 16-20, 1985, Beijing, China, pp. 33.

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KINOSHITA TAKAHASHI, ,T. MIKAMId an , , (1982,M. T. ) "Cytoplasmic mutation of male sterility induced by chemical mutagens in sugar beets", Proc. Japan Acad., 58_, Ser. B, pp. 319-322.

KONZAK, C.F., (1984) "Role of induced mutations". In: Crop Breeding, a contempory basis, eds. P.B. Vose, S.G. Blixt, Pergamon Press, pp. 216-292. LARSEN, J., (1981) Breeding of Proanthocyanidin-free malt barley, Barley Genetic Edinburgh, IV s . 211-216,pp .

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MALUSZYNSKI , (1982. ,M ) "The high mutagenic effectivenes f MNUo sn i A inducing a diversity of dwarf and semi-dwarf forms of spring barley", Acta Societatis Botanicorum Poloniae . 3-4429-440. 51 ,pp , .

McKENZIE, K.S. d RUTGER,an , J.N., (1984) "Evaluatio f induceno d semi-dwarf mutants of rice for the Southern United States", Progress report presented during the Third FAO/IAEA RCM on Evaluation of mi-dwarf Cereal Mutants for Cross-breeding, Ciudad Obregon, Mexico, 6 April2- , 1984.

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MICKE, A., DONINI, B., and MALUSZYNSKI, M. , (1987) "Induced mutations for crop improvement - a review, Tropical Agriculture (in press).

29 MICKE, A., MALUSZYNSK1, M., DONINI, B. (1985) Plant cultivars derived from mutatio f o induce e n us dinductio e mutantth n r crosi o sn s breeding, Mutation Breeding Review IAEA, 3_ , , Vienna . 1-92pp , .

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RIGGS, T.J., HANSON, P.R., START, N.D., MILES, D.M., MORGAN, C.L.d an , FORD, M.A., (1981) Comparison of spring barley varieties grown in England and Wales between 1880 and 1980. The Journal of Agricultural Sciences, 97. pp. 599-610.

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RUTGER, J.N., PETERSON, M.L., HU, C.H. and LEHMAN, W.F., (1976) Induction of useful short stature and early maturing mutants in two japonica rice cultivars, Crop Science, 16, pp. 631-635.

RUTGER, J.N., PETERSON, M.L. and HU, C.H., (1977) Registration of Calrose 76 rice, Crop Scienc. 978p .. 16 e

RUTGER, J.N., (1983) Applications of induced and spontaneous mutation in rice breedin d geneticsan g , Advance n Agronomyi s. 383-413 pp . ,36 .

RUTGER, J.N., AZZINI, L.E. d BROOKHOUZEN,an , P.J. Inheritanc f semio e - dwarf and other useful mutant genes in rice, Proceedings of International Rice Genetics Symposium, 27-31 May 1985, Los Banos, IRRI (in press).

SATO KANEDA, ,H. , (1981. Ch , ) "Rice (Oryza Sativa L.)" : SeedIn , d an s Seedlings in Japan, Association of Agricultural Relations in Asia, pp. 150-165.

SIGURBJORNSSON , (1983,B. ) "Induced mutations" : CroIn ,p Breeding, (Eds) D.R. Wood, American Society of Agronomy and Crop Science Society of America, Madison, Wisconsin pp. 153-176.

SIMMONDS, N.W., (1984) "Gene manipulatio pland an n t breeding", : GenIn e manipulatio n plani n t improvement. 16th Stadler Genetics Symposium. Edited by J.P. Gustafson, Plenum Press, New York, pp. 637-654.

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30 PROJECT REPORTS EXAMINATION OF DWARF WHEATS PRODUCED BY MUTATION, CROSSIN PHYSIOLOGICAD GAN L PROCEDURES

. BARABÄSZ . KERTÉSZ , Z Cereal Research Institute, Szeged, Hungary

Abstract

By induced mutations more than 2OOO dwarf lines were produced and 16OO were examined in ear-to-row experiments in 1984-85. The new dwarf forms showed a reduction in height of 11-28 per cent as compared to the parental cultivars. By "cleanin e genetith " up cg background euplasmic new dwarf forms can be produced and the productivity of which reaches that of the tall ones, possibly because of the elimination of chromosome and cytoplasm aberrations. Genetic analysi f dwaro s f wheats verified, that in combining ability for height Mini Manö proved to e bestth ,e b reducin hybrids e heighit th g f y moro tb s e than 7 cm. As Mini Manö has a number of excellent characteristics it seems to be very promising both as a cultivar and as a crossing parent. The internode length of 45 F, hybrids, along with their parents, was measured in the field. Three of the parents involved /Mv 3, Gödöllö l and Gödöllö 2/ were of mutation origin. The behaviour of Apollo cv. s verwa y favourable n almosI . l crostal s combinations it reduced the length of the first internodes and increase e pedunclth d e length. Using tissue culture methods somaclonal variants inumbea n f characteristico r s have been produced. For improving the characteristics of dwarf lines, pro- generation, F. d geniean ~ F f thei so s, wer, - F r in e cluded in the haploid breeding program. A number of androgenetic doubled haploids have been improved. More than 5.000 gametoclone and/or somaclone lines are under tests in field nurseries. Reduction of the influence of gravitation results a reductios wel a n i l heightn i n .

. Introductio1 n The average yield of wheat on a country-wide scal n acreagO t/ha 3 milliocloss 5. i e1. n a o o f t eeo n hectares which represent e tota e fiftth on slf o h lands in Hungary. The top yield on the best fields reached n experimenta i O t/h1 d aan l conditions 11-12 t/he aar not exceptional. On this level of production the strong

33 dwarf straw of the cereals is a crucial requirement. e Hungariath Mos f o t n wheat e semi-dwarfsar d soman s e newer one e dwarfar s s /60-7 heightn i m 0c / sucs a h X MinG d i an Man 3 M1 öv whic e beinar h g introducen o d a large farm scale. Our mutation work started about ten years ago /Barabâs, 1977/ but the yield of dwarfs obtained so far did not reach that of the parentals. However, Micke et al. recently /1935/ reported on more than a dosen productive dwarf cultivars of mutant origin. Since 198 e result0th n thii s s field have been summarized in 1982, 1983 and 1984 in Vienna, Davis, and Ciudad Obregon, respectively. Now we would like only briefly to dwell upon the conclusions of earlier reports, focusing on the new facets of the methods, result d problem san e dwarfis th f o sn i m wheat.

2. Induction and selection of dwarf mutants Seed f cultivaro s s Partizank d Jubilejnayan a a 0 wer5 e expose. kR 5 o gamm1 t d d aan radiatioO 1 , 5 f o n After growine singlth p u eg see , generationM d ,a selection of semi-dwarf and dwarf variants was carrie t froou d m population , differenM- d an 2 n M ti s two successive seasons. Altogether 20OO semi-dwarf variants were selected so far /Barabäs & Kertész, 1982/. In 1985 1600 putative dwarf mutants, selected earlier were grown and evaluated in an ear-to-row nursery. Each progen m lony 2 representeg1. w ro e on d with a distance of 20 cm between the rows, resulting in a density of about 40O seedlings per m^. This density is close to that used in the farm practice. According to our methodological experiment /G. Erdei, 1985/ it provides a reliable information aüout their real productivity. Each sixth plot /row/ was used as a control and compised nontreated cultivars. The newly obtained induced dwarf mutants on the mutant genetic backgroun d cytoplasan d f pooremo provee b ro t d performance compare e originath o t d l cultivars /Table I/. However, there were some exceptions. The best dwarf mutant of Partizanka reached the yield of the parenta e beslth t lin d Jubilejnayan e a mutant dwarf showed onl% yiel10 y d reductio s comparea n o t d the original form. From this reselected mutant lines som0 80 e dwarfs were planted along wite parent earth n ha -n i s to-row experimen e fal th f 1985o ln i t . Besides chis, 0 line5 s wil e teste b la dril n i dl plot screening a replicate n i nurser 5 d dan y yield trial.

34 TABL Heigh. I E yield tan d reductio f dwarno f mutants /on mutant genetic background and treated cytoplasm/

No. of Average height Average yield mutant reduction reduction families cm % %

Par tzânki a 31 1O-25 11-29 30-50 Jub:lpjnayO S a 30 10-25 11-28 3O-4O

3. Back-cross progra r "cleanin fo e mgeneti th " up cg background of the mutants

Althoug e bes e yielth tth hf o mutantd s simii s - n somi e, la or casesr , equae parenta th o that lf o t l cultivars, they are by no means competitive with the best cross lines registered wels i lt I .know n that mutagen treated cytoplasm /and genetical background/ cause a setback in productivity. Gustafsson /1961/ reaches the conclusion that the nucleus is relatively radio-resistan e injurieth d an t s aren ,i general, of cytoplasmic origin. In Sorghum the ex- change of the mutant cytoplasm with a normal one resulted a significant increase in the yield /in: Barabâs, 1964/. This e achievechangb n ca ey back b d - -crossing y gameti,b c selections usin s linesm g y b , Chase /1963/ androgenetic methode th y b wels , a s a l o datut p e protoplast culture methods. Cleanin e genetith p u gc backgroun e dwarth f o d M-.-MI- mutant s beini s g carrie t sincou d e 1983t .A presen 4 mutan4 t t 6 mutanline2 f o st familie4 3 d san mutant 0 mutanline2 f o st familie n differeni e ar s t stage of back-cross /BC-,-BC2/ generations from Par- tizank d Jubilejnayan a , respectively50 a e M33Th . O mutant on the original montreated/ background has a reduced height and a better vitality than that on the mutant background. Similar tendenc s founwa y d 6 Partizank6 M ine th cas af eo mutant etc.

. Combinin4 g abilit f dwarfo y r heighfo s t The behaviour of a series of dwarf wheats was studied in a diallel crossing program analysing F-, angenerations- F df whea o t tse linee Th .s studied was as follows: Krasnodar 1, Karcagi AM 522, Tom Thumb, Bulgariaa s A n. C. dwarf v H o dwar ,d Ap an f tall teste e welth rl adapted cultivar Jubilejnay0 5 a s usedwa . Accordin e generath o t gl combining ability e lineoth f s e "Ap/Tablth o, dwarf2/ e worts i " f o h attention.

35 TABL . GeneraII E l combining abilit r heighfo y n dwari t f wheat lines

Lines General combining ability values /cm/

1. Jubilejnay 0 /tal5 a l tester/ 6.89

2. Krasnodar 1 1.76 3. Karcagi AÎ1 522 2.22

m Thum4To . b 0.46

5. Bulgarian dwarf 0.44

o dwar6.Ap f -12.00 7. Mv C, 0.23

It reduced the height of its F-, progenies by an . Thicm averag s2 1 resul f o e t also indicated that dominant dwarf gene/s/ controls the height of this particular line. Segregatio n~ confirmeF tes n i t d that the dwarf carries one single gene for dwarfness and shows complets 1 dominanc3: basie a th f o sn eo - shor tal: t l segregatio nJubilejnaye ratith n i o a o dwarAp X f crossing e favourabln spitth .I f o e e properties of this line difficulties arised in fixing its height t showI . s sometime sa rando m segregation ratio /perhaps chromosomal aberrations on 4A/ in spite of 10 generation selfing. Ia top-crosn s series including mor, eF tha0 10 n hybrids of 31 parents, Mini Manö is being tested and evaluate , analysisF e a parentbasie th s th a df o sn ,O . the general combining ability of the parents for heigh d soman t e other agronomic trait beins i s g tested under greenhouse conditions. In this trial, Mini Manx 158/M ö / produce- ex d cellent F, progenies, and proved to be the best among the lines. It reduced the height of its hybrids by n anothei m c r9 e serie5. on y n f b testi o s 7. d m c 3an s compared to the overall average of the hybrids /Table 3/. Besides the very good agronomic characteristics of this line Mini Manö e seemverb o yt s promisinn i g producing SD hybrid populations and finally SD cultivars. Both in our performance nurseries and in state yield trials Mini Man s equawa ö r superioo l n yieli r d as compared to the other cultivars with normal height although Mini Manö is just half as tall as Jubilejnaya 50 /65 vs 120 cm/. Compared to the released dwarf s yieldinfeed-wheait / 13 g v abilite same/M t th s ,i y but it has a better resistance to stem rust, leaf rust, mildew, and shows higher tolerance against aphid and Barley Yellow Dwarf Viras as well. Its drought

36 TABLE III. General combining abilit r heighfo y n i t cultivar w candidatene d san s

Entries Combining ability values /cm/

- 7,31 GK Mini Manö

Zld - Ttj 3,35 8001 - Zld 1,49

Pdj 2 - Sv 2,45 3,7- 5 1 M1 v

3 a Rn Rsk-R x 2 1 n 3,84 Csg-Zg 4364 - O,O5

234.13 - Bzt 1 - 2,04 Tpr 349 x 8OO1 - Sv O,72

- 3,78 2 s GT-PdU x 2 j Jbj-Sdv "S" 6,O7

- 1,O5 453.60 Prt- 2 k Rsk-Rn 12 x Rbn O,O5

toleranc d bakinan e g qualit s excellenti y , compareo t d the other dwarf and tall wheats. On the basis of these, Mini Manö is very promising both as a cultivar and as a crossing parent kindls i t I .y suggeste o wintet d r wheat breeders. It might be released next year in Hungary. /Kertés Barabâs& z , 1984/. 5. GA-insensitivity test of Hungarian SD wheat lines O semi-dwar2 f O d dwaran f f lines widely usen i d crossing programs, the following proved to be insensitive: Gödöllö 2, Rf Super 2, Mini Manö, Apo dwarf, Apollo and Mv 5 /Table 4/.

6 . Inheritance of the internode length of the mutants e internodTh , hybridseF lengt5 4 f o h, along with their parents s measure wa ,e field th n i d. Thref o e the parents involved /OKI, DK3 and DK9, Mv 8, Gö- d Gödölldöllan 1 ö, respectively 2 ö / wer f mutatioo e n origin. Although Gödöllö l had a short culm its first d seconan d internodes were extremle yth lond an g peduncle was relatively short. This characteristic was

37 TABLE IV. GA insensitive lines and their culm length

Entry Culm length /cm/

Godöll2 ö 56,5

Rf Super 2 6O,O

Mini llano 6O,O

Apo 4b,0

Apollo 69,8

67,3

",'ERNODE LENGT DK3F O HLINE4 THEID ,DK SAN R c-i F! PROGENIES

1 H T rr T n- i i "i [f 1 i1 1 1 T ]|!| !, ll ' ' f i 5th L ,1 Ll J, i; ni * ü 111 Lj u jljf J4 * ^j I i 1 n i , J ( 1 1 1 1 ,f -, i U ( 1 ^'h 1 ] • .-n , T l f i , , (^ 1 ' • i - 1 t ÜJ i' ' Q 3rd o 1 1 1 — i 1 J ( L ^ i. M z [X 1 r " 1 f r: ,!^i 1 1 J i ' i 1 {

lst Un m IT TTî Jl IE * ÉÉ

Q Q o o Qo o D a o Q O O D O QQ Q oj r-w »J f> iDiji i& ij3 r^r^ ao m cr> OO ^^ ^ :*: ^x; *: *: s:^ ^^c x: *: ^:^ QQ QQ QQ QQ QQ QQ QQ OH

/"CtOcJ- previous DFI Mv~8 Mv 4 GodolloJ. JK4 Apollo DK5 Szeged LT6 Mv 5 EK7 Mv 1C3W DK8 Szil. 2 DK9 Godollo 2 DK10 Mr8 n80 * nutants underlined

Pig-are l Internode length of DK3, DK4 lines and their F1 progenies

38 rather disadvantageou r producinfo s g hybrid d linesan s wit n ideaa h l culm structure e otheth rn O .han e th d behaviou s verf Apollo rwa y. favourablecv o n almosI . t all cross combinations it reduced the length of the first internode d increasean s e pedunclth d e length/Fig/ I .

7. Mutants obtained by means of biotechnological procedures e laso yearIth ntw t a srelativel y large number of somaclone d gametoclonean s s were produced from bread wheat, durum wheat and some interspecific hybrids. At present /1985 winter/ some 15OO C plot/somacloneS f o s / progenies and some 4OOO plots of gametoclones /androgenetic doubled haploids e plantee nurseryar /th n i d . About 50 of the SC and GC progeny generations were plante a replicate n i d d yield trial. A distinct reductio n heighi ne s founth wa tn i d SC-, progenie e Minth if so Man ö somaclones e SC-s th :, wa almost 5O% shorter than the parental form. In the next SC2 generation the reduction in height was minimal only, 7-5% of the original Mini Manö, which grew 47 cm high under greenhouse conditions. Among the 18 second SC generation progenie 2 line f o ss provee signifib o t d - cantly shorte 2 talle d an rr thae parentath n l line. 2 familieSC e th Non sf o eshowe d significant increasn i e kernels /head, and Harvest index/. Only one family had higher seed-weight/head value. Otherwise in 6 cases the SCp families surpasse e controth d l Mini Man n 1OOi ö O kernel weight. In another experiment with another cultivars: 17 from 37 SC2 families of GK Kincsö and GX Csongor showed differences in various morphological traits as compare e parentsth o t d . Change heighn i s t were observed e obtaineanth d d reduction varied from 14-35 s coma % - pared to the original cultivars. These changes were inherited in SC? and SC-, generations as well. /Galiba & Kor- tész et al. 1985/. No doubt, these types of the dwarfs e promisinb see o t m r practicafo g l breeding purposes. e mosth t f o remarkabl e On e biotechnologica- ex l periments is the application of normally reproduced whea x tbarle y hybride breedinth n i s g practice along- with biotechnological methods y producinB . g somaclones and possibly gametoclones from steril wheat x barley hybrids we hope to transfer the dwarfness and standing ability of wheat to barley plants, and vice versa - the characte f Fusariuo r m nivale resistance from barleo t y wheat.

. Inductio8 f dwaro n f modification y changinb s e th g influenc f gravitatioo e n

The height of wheat plant can be considerably reduce y layinb d t horizontallg po dowe th n d dailan y y turnin twict i g e 18O-18 Turnin. O e potth gs roune th d

39 vertical axis cause o modificationn s e horizontaTh . l treatment reduce e longitudinath s l e plangrowtth tf o h by 2O-40%, presumably by the alteration of the influence of gravitation. This effect causes further height reductio e dwarth fn i nMin i Mano s sid.A e effects heading difficulties and other teratological symptoms also occu n somi r e cases . 1935//Sâgal t ie . (Fig) 2 .

Control Treatments U Ù

Figure 2. Influence of gravitation

The growth inhibition affecte y turninb d e th g pots roun horizontae th d l axit necessarilno s y causes other stresses. E.g. in one of our experiments resistant and moderately resistant wheat varieties /Mini Manö and Mv 10/ were artificially infected by powdery mildew. The epidemic level of mildew was similar in both the horizontally and the vertically treated /by turning/ as well as in nontreated plants. Naturally, the dwarf modificatio y horizontab n l turning continues e effecth s a t r existsfa onl s d changea yan , a s sa function of the time and treatment. We think that the so called gravitation experiments will brin s closeu g r o bettet r knowledg e physiologicath f o e l backgrounf o d dwarf growth.

Acknowledgement Appreciatio . Sutks expresseJ i no . wh a Dr o t d f diallelo providet se e th F,-d d parentsan r fo s internode-studies.

40 REFERENCES

BARABÂS, Z.,1965: Induced quantitative somatic mutants in Sorghum. The Use of Induced Mutations in Plant Breeding, : RadiâtIn . Bot. Suppl : 515-5205 . . BARABÄS, Z.,1977: Preventio f geno n e erosiod ol f no wheat varietie y back-crossinsb d X-raan g y irradiation. Proc.Induced Mutation Against Plant Diseases. IAEA, Vienna (1977) 29-32. BARABÄS, Z., KERTÉSZ, Z., 1982: Production and evaluation of dwarf and semi-dwarf winter wheat mutants. Proc. 2nd Res.Co-ordination Meeting on Evaluation of Semi-dwarf Mutants for Cross Breeding. Davis, California, USA, IAEA, Vienna, TECDOC No. 307 (1984). CHASE, S.S.,1963 :r transfe Androgenesifo e us r s it - s of maize cytoplasm. J. Hered. 54:152-157. ERDEI G., 1985: Buza genotipusok produktivitäsa 75, 15O, 3OO O szem/6O , m allomänysürüsegben. Szemi- nariumi elöadas, GKI, 1985. GALIBA , XERTÉSZ,G. SUTKA, Z. , , SÄGI 1985,J. , L. , : Difference n somaclonai s l variatio n threi n e winter wheat /Triticum aestivum L./ varieties. Cereal Research Communication : 343-35013 s . GUSTAFSSON, A., 1961. The induction of mutations as a metho n plani d t breeding.Mechanismu n Radioi s - biology, Vol ! 479-497I . . KERTÉSZ, Z., BARABÄS, Z., 1984: Agronomic evaluation and genetic analysis of dwarf/semi dwarf Hungarian wheat strains and mutants. Paper presented on the 3rd Research Co-ordination Meetin n Evaluatioo g n of Semi-dwarf Cereal Mutant r Crosfo s s Breeding, Mexico (1984) (unpublished). HICKE, A., MALUSZYNSKI, M. , DONINI, B., 1985: Plant cultivars derived from mutation induction or the use of induced mutants in cross breeding. Mutation Breeding Review. No. 3', 1-92. . LOMNICZIS SÂGI , F. ,1984, H. , : Csökkentett gravitâciô hatâs a durumbuzära a /Triticum durum Desf./, Bot. Közlem. 71:233-240.

41 EVALUATION OF SEMI-DWARF MUTANTS IN TRITICALE AND WHEAT BREEDING

C.J. DRISCOLL Waite Agricultural Research Institute, Universit f Adelaideo y , Glen Osmond, South Australia, Australia

Abstract

triticalo Tw ewer A linesIR e - subjecte , BeaglR D d eitheean o d t S r X-rayM E. r so and later generation derivatives score r heighd fo yieldd singl9 an t 21 plan2 . eM t selections were reduce line8 1 r replicate o sfo dt d yield analysis basie th intervenine f yielsn o th o , n di g generations. Higher yielding selections appear to have been isolated; however, they are not notably shorter than the controls.

Wheat Composite Crosses have been established X-rae baseth n yd o induced nuclear male-sterility mutant 'Cornerstone'. Derivatives, following three rounds of obligatory outcrossing, include high yielding lines. Composite Crosses appear to be more successful if they are homogeneous for a semi-dwarf allele.

. I Induced Mutation Shorr sfo t Statur Triticaln ei e Triticale production is continuing to increase in Australia with 163,000 ha. grown in 1985 whic 627a s hi % increase since 1980 mose Th . t successful genotype Australin si e th e aar long headed types that contai l seven al chromosomes e nry . This typ planf eo representes ti e th y db CIMMYT selection - IRAs talls R Beaglcm D ,. 0 d Thes11 an e d e an line s scm wer0 12 e respectively, in good field growing conditions in 1983 and 100 cms and 85 cms in poorer field growing condition 1984n si . Dormant seed of the two lines were subjected to mutagen treatment in 1977 in order induco t e height variants separato Tw . e treatments were applie boto dt h lines, viz.X-rayK 5 ,2 s and 0.5% E.M.S. 219 singl plan2 M e t selections wer f theso e7 e4 mad werd ean e g takeM o nt replicated yield plot 198n i s replication3 4( location)1 d an se selectio Th . n method employed before and after the Mc placed major emphasis on the yielding ability of the selections rather than the retentio f variouno s height classes. e 198Th 4 report detaile heighe dth t distribution selection9 4 e e 198th th f o sn 4si trials e 198Th . 4 yield data have been analyse line8 1 sd werdan e selecte inclusior dfo 198e th n 5ni yield tesreplication3 ( t eact locations)4 sa f ho 198e Th 4. yield performanc linee th sf eo retaine d in 1985 are shown in Tables I and II. Two of the four 1985 sites had been harvested by mid-Decembe meae th nd uncorrecteran d weigh three th ef to replication siteo showe tw sar e nth f so in. TableII d an sI

Two points emerge from these observations. One, although no higher-yielding Beagle selections have been isolated, higher-yielding lines of DR - IRA appear to have been isolated. For example, DR - IRA Irrad-129 and Irrad-61 have consistently yielded highly.

e seconTh d hige pointh hs i tyieldin g selection t noticablno e sar y reduce heightn di . selectionA 8 IR controe - A th R IR d s- D an lrang n R te D heighe e e 119th o froth t Th f f 4 %o mto 9 Beagle selections vary 105o Beaglfroe t th 5 m %9 f o e control.

43 TABLE I. 1985 uncorrected yield 198d san 4 corrected yieldd san selectionA IR - controld R D san n heightte .e th f so 1985 Yield 1984 Yield Height (% Control) (%Control) (% Control)

Irrad - 129 157 146 106 Irrad - 61 126 130 94 EMS- 64 117 127 119 EMS- 20 115 182 100 Iirad - 87 111 145 94 Irrad - 54 105 184 119 EMS- 41 105 134 106 *DR- IRA Control 100 100 100 EMS- 24 98 115 106 Irrad - 45 97 146 112 EMS- 11 47 132 100

*DR - LRA Control : 1985 uncorrected yield (average of 3 replications at each of two sites) 1.9 t ha '*, 1984 NN ANAL corrected yield 1.0 t ha ~l ; 85 cms.

TABLE II. 1985 uncorrectred yields and 1984 corrected yields and heights of the eight Beagle selection controld san . 1985 Yield 1984 Yield Height (% Control) (% Control) (% Control)

* Beagle control 100 100 100 EMS - 36 94 98 100 EMS - 41 93 91 100 EMS - 63 87 92 95 EM0 5 S- 85 104 110 EMS -3 78 93 100 0 2 - S EM 77 96 100 9 3 - S EM 73 120 95 4 5 - S EM 73 98 105

* Beagle Control : 1985 uncorrected yields (averag replication3 f eo s at each of two sites) 2.8 t ha -1. 1984 NN ANAL corrected yield 2.1 t ha -1 .0 cms10 .

44 Potentially usefu genotypelA improveER - r crossbreedinR fo s D d d havgan e already been use thir dfo s purpos generae th n ei l breeding program. They directlwoule b t dno y usefu varieties a l recentle th s sa y released variety "Currency same th en "i 1984 yield trial yielded 310% of the DR - IRA control.

. II Composite Crosse GailRhtd an sWhean i 1 t Wheat breeding often involves crossin o parenttw gd thean sn selfino t g homozygosity accompanied by evaluation of yield, agronomic and other traits. Variation on this theme involves crossing Fj's to a third parent, and recycling F^'s, for example, as parents. In general, the heterozygous phase is limited. Composite Crosses nuclea e baseth n do r male sterility mutant 'Cornerstone' extends the heterozygous phase by enforcing outcrossing. Composite Crosses have been established by crossing Cornerstone with a number of wheat lines, and growing a mixed ?2 usually of 1,000 plants. The ?2 segregates fertiles: stériles and the latter are pollinated by fertiles at random. Ten seeds fro mselecte0 eac10 f ho d sterile usee sar produc o dt nexe eth t generation. This procedurs ei repeated until thers bee ha t ea leas n t three round f randoo s m outcrossing. [1-3] Following this, homozygous fertile selection made subjectesar d ean yielo dt d tests. Fou ) rhav CompositV ewitd p u beean ht I nyielse II , e II dCrosse , increasI C maie th s(C ns ea objective. The male parents used in these Composites are shown in Table III. Each Composite Cross appears to be an improvement on the one that was established earlier than it. There are two

Table III. Male parents used in the Composite Crosses I, II, HI and V.

CCI CCII

Condor Condor x Warimba Gamenya Egre Warimbtx a Gamset Gab Warimbox a Kite Halberd x Warimba Pitic Kite x Warimba R/11* Warimbx K ) * 8 1/ M ( a Timgalen WW15 Olympic* 8156 / 20/9x Warimba Zenith Oxle Warimbyx a Warimbx 7 17 - aC A R WarimbX 5 1 W a W V CC CCIII

Aroona Aroona Avocet Banks Banks Cook Matipo Oxley Oxley Suneca Toquifen Warimba Warigal Warigal

45 reason male-sterile r thissfo Th . e female paren bees ha t n continually improved t normalli d an , y contributes 50% of the alleles to the Composite. The pedigrees of the female parents are shown in Table IV.

Table IV. Pedigrees of the male-sterile female parent of Composite Crosses . IV d an I II , II , I

CCI Federation 12 * Pitic.

ecu Federatio Piti* 2 nß 1 cI Gameny* Warimba/ 3 a/ .

CCIII Federation / 2 * Pitic //3 * WW15.

ccv Federatio Piti* 2 nß 1 cI * WW15/3/Oxley.

Table V. High yielding lines derived from CCII in 1984.

Rank Entry Corrected Weight

1 CCII -2 13 442 2 FW CCII -5 1/1 439 3 FW CCII -49/1 431 4 FW CCII -82/1 424 5 Aroona Control 413 6 FW CCII -73/1 412 7 CCH9 17 - 378 8 FW CCII - 4/4 375 9 FWCCII- 12/1 374 10 CCIW F I -46/1 369 11 FWCCn-50/1 368 12 FW CCI I33/- 2 364 13 FWCCII- 113/1 366 14 CCII- 166 361 15 CC0 8 U - 360 16 Condor Control 358 17 CCII - 18 355 18 CCI2 14 - I 355 19 FW CCI 47/I- 2 354 20 CCII3 15 - 353 21 CCII - 204 351 22 9 CCI28 - I 350

46 secone Th d reaso reductioe th numbee s ni th f n o talf ro l plant laten si r Composite Crosses. The earlier composites included tall pollen parents and the heterozygosity generated by intercrossing resulte larga n di e proportio f talno l wheats male-stenle C Th C . d an I II e stocC C f ko V were homozygou sl polle GailRhtal d nan parent1 f eaco s h were homozygous GailRhtI Hence, excessively tall wheats were not a feature of CC III and V and this is reflected in lines that have been extracted from CC III. CC I produced high yielding lines [5], however all except one was found to have flour quality problems. The one line that has been retained (CC I 61 S/5) has been re-selected and 60 sub-lines of it are in the process of being yield evaluated alsI I oC produceC numbeda f higro h yielding lines (see Tabl . TheseV) e have t beeye ns a subjecte t no qualito t d y evaluation These high yieldin greplicatedn i line e ar s , multi-location yield trial 1985n si . werI I However d e an disadvantage I C C , segregatioy db f dwarfinno g alleles, in that many of the selections were excessively tall. The CC III composite has not had this problem and the derived selections are all of reasonable height Of 1,080 CC III derived rows grown in homozygou6 198530 , s fertile rows have been selecte replicater dfo d yield trial 198n si 6 e otheTh r e inferioprobleth s rwa m I flou witC rC h qualite deriveth f o yd high yielding lines. CC V has been set up with good flour quality lines only With the restrictio f goono d qualit homogeneitd yan GailRhte th f yo 1 alleleshoul V C C ,d produc elarga e proportion of acceptable derivatives. The danger is excessive restriction on entries could result in insufficient heterozygosity Success of Composite Cross breeding requires, one, an improved genotype of the male-sterile parent and, two, a restncuon(s) on the pollen parents introduced into the composite The X-ray induced nuclear male sterility line 'Cornerstone' is suitable for Composite Cross breeding and the effectiveness of this bleeding method depends upon the two points that have been emphasised[4].

REFERENCES [1] DRISCOLL, C.J. "New approache wheao st t breeding", Wheat Science - Today and Tomorrow ( L T. EVANS and W. PEACOCJ ) Cambridgs KEd e University Press (1981) ] [2 Cornerstonf DRISCOLLo e us e Th e ,mal C.J. e sterilit whean yi t breeding (Pioc 6th International Wheat Genetics Symposium, Kyoto,1983). (1983) 669

] [3 DRISCOLL contributioe , C.JTh . cytogeneticf no plano st t improvement (Proc XV International Congres f Geneticsso Delhiw Ne , , 1983). (1984) 69.

] [4 DRISCOLL, C.J. "Nuclear male sterility system seen si d productio hybrif no d varieties" CriticaC CR . l Reviews, Boca Raton, Fl. U.S.A. (in press). [5] KAEHNE, I.D. and DRISCOLL, C.J. - Cornerstone nuclear male sterility and wheat composite crosses. (Proc Australian Plant Breeding Conference, Adelaide, 1983.) (1983) 109.

47 EVALUATIO MUTANF NO T STOCKR SFO SEMI-DWARF PLANT TYPE AS MATERIAL FOR CROSS-BREEDING IN DURUM WHEAT

K.A. FILEV Institute of Genetics, Sofia, Bulgaria

Abstract

Mutation breedin s bee ha n ga importan n e durut th par f mo t wheat breeding programme for reduced height, lodging and cold resistance. A scheme has been tested, which makes it possible to speed up the plant breeding period and create valuable semi- dwarf durum wheat lines or cultivars. A close correlation was found between: plant height and length of the last internode, weight of grain of main spike and yield per plant, tillerin d yiel r an gplant pe d d numbean , f graio r f maio n n spike and grain weigh f maio t n spike e obtaineTh . d results indicated that short stature mutant lines with different semi-dwarf genes and GA response have been created, characterize y colb d dlodgin an d g resistance, high yielding potential and protein content. Some of them proved to be a valuable cross-breeding materia n durui l m wheat, other r examplefo s , Lose , wer76 ne directly w cultivarreleasene a s a d .

INTRODUCTION e mosTh e tduru th importan mf o whea m ai tt breeding programme th f o e Institute of Genetics in Sofia and the Institute of Cotton in Chirpan is to obtain cultivars with semi-dwarf type, cold and lodging resistance, early maturity, high yield potential with good technological charactery b s using radiatio d chemicaan n l mutagenic agents. This report gives data about the more valuable durum wheat mutants and the methods of their creation.

Materials and methods r investigationIou n s local cultivar r line o sd Italia an s n cultivars Castelporziano and Creso were used for the creation of new mutant lines by mutagenesi d hybridizatioan s n [1,3,4,5]. Agronomic trials have been carried out in four replications, with the size of every plot being 10 m^. The protein content was calculated by estimating nitrogen content, e.g. by the Kjeldahl method. For the estimation of yield components, 100 plants of each line and cultivar were analysed. The method to analyse GA respons s giveewa previou n i n s publications [5].

Results and discussion

e useW d mutation, hybridizatio d individuaan n l selection methodr fo s improvement of durum wheat. The scheme of the current investigation is show A n greaFiguri n . 1 t e genetic recombinatio s notewa n d after irradiation of hybrids. Progeny lines selected up to BC^M^F^ generations growing under stress conditions, showed a great frequency of

49 1 . Crossing after irradiation . gaJnetophytP d an . P e eoth f

or ? spikeP onl f yo s .emascu- lation of P. flowers and pollination wi'tirradiatee th h d pollen (150 0200- 0 rada) M P Backcros. 2 P polleer o wit . nhP. 1 1 irradiated with 100 0- 150 0 rada wit viea h receivo t w e compound hybrids . Individua. 3 l sowing B(Wi

4. Individual selection (l) of BC1M2P2 semi-dwarftcold resistant progenies

Individua. 5 l selectio) (2 n BC.M.

comparison witstandarde th h .

6. Microtrial,individual selec- BC M F tio) semi-dwar(3 n f plant height, 4 4 1 yield,cold resistance and protein content.

Preliminar. 7 y triareplication4 n i l s m 5 n i

. Strai8 n triareplication4 n i l s BC1M6P6 in 10 m simultaneously at the Institut Nationae th d an el Strain Testing Board.

Fig. 1. Scheme proposed to incorporate some promising characters of P, (cold resistant, good quality

but tald lodgingan l ? genotypP o t ) e (semi- dwarf gene scource) using garnetophyte irradiation and crossing in durum wheat

plants with such characteristics as semi-dwarfness, cold resistance and high protein content with improved yield.

e resultTh f threo s e years researc n yielo h d component f severao s l durum wheat mutants are shown on Table 1. The mutants lines are considerably shorter (38.8 - 50.5% ) when compared witparene th h t cultivar N788. The lines 15/4-2 and Zeverjana are shorter by 9.8 and 7.8% than the semi-dwarf cultivar Creso. The number of tillers is close to that of cultivar N788, but the most important yield components as the number of spikelets per spike, the number of grains in the main spike, the weight of the main spike grains and the weight of the whole plant grains, were found to exceed the parent cultivars [2].

50 Tabl . 1 e Yield component f duruo s m wheat mutant 3 yea( s r average)

ti .s u * u M l'^a^L height Tillering No of product- Grains per Weight of Weight of ( er ) ( S\ ) ive soikelcts ma in sp ike grain/ grain '

pnr &3lke n spiki ) a m (g e plant 1' ê ^

M 3D M su M im 3D M -m 3D M -m 3D M -n, SD

Ambra 7/,5 1,2 6,1 4,5 0,3 1,5 15,2 0,3 1,5 46,4 1,3 9,3 2,4 0,1 0,6 11,6 0,8 4,0 15/4-2 61,7 1,0 5,0 4,6 0,3 1,4 16,0 0,3 1,4 39,9 1,4 7,5 2,0 0,1 0,5 6,8 0,5 2,8 159 76,0 1,2 6,0 4,0 0,2 1,1 17,8 0,3 1,5 44,0 1,3 6,7 2,6 0,1 0,6 10,4 0,5 2,8

6 7 3, 3 12,7 0, 19, 54,1, 1, 7 1 0, 23 0, 3 0 4 10,6 0, 0, 2, 0 , 2 LoneJ 4 4, b ,' n1 01,6, 2 31,

720-C 73,7 1,3 6,9 3,7 0,2 1,0 18,7 0,3 1,4 47,4 2,0 10,6 2,5 0,1 0,6 10,3 0,4 2,5

Zeverjana 63,1 0,9 4,5 4,D 0,4 1,9 17,8 0,3 1,6 45,4 1,0 9,3 2,2 0,1 0,5 11,2 0,8 4,0

0 3, 5 0, 1 9, 4 0, 0 1, 6 1, 6 2 6 5, 29,16,1, «1, 7 82 0 3 886 0, 1, 0, 3 4, 124,1 6, 1 71, Creso 68,4 1,2 5,0 3,9 0,1 0,8 17,0 1,7 2,8 37,3 2,2 9,3 1,8 0,5 0,3 8,9 0,4 2,3 Castel- 73,2 0,6 2,0 2,6 0,2 0,8 10,2 0,3 1,0 46,2 2,9 9,4 2,4 0,2 0,6 9,0 0,6 2,0 porziano

The stem of durum wheat is mainly composed of 5-6 internodes. The last (1st uppermost) internode of durum wheat is longer than that of ordinary wheat and constitutes from 39 to 54% of the total stem length of various cultivars, mutant d linesan s A positiv. e correlation betweee th n plant heighe d lasth lengtan t f o hinternod e (r=0.98*** s foundwa ) . 3 illustrat Figurd an 2 e e thae e laslengtth th tt f o hinternod e decreases wite decreasth h f plano e t height.

As seen in Figure 2, eight lodging resistant mutants possess the same number of internodes. It is clear that shortness is not necessarily correlated with reduction in the number of internodes. Tn fact the V internode d an V I s, shorteninII concomitan e e th lengthenin th f o o g t t g e uppermosth f o t ones, whic s associatei h d with straw stiffness. Datn o a e numbeth f internodeo r s shows thae steth tm structur e majoritth f o ef o y mutants is not different from that of N788.

The results regarding the yield components show that there is a possibilit r planfo y t height reductio n durui n m wheat without interferring negatively on other agronomically important traits. Our results had reconfirme e previou f th Scarascia-Mugnozzdo e on s d Bozzinan a i [8].

Figur 4 eillustrate e relationshith s p betwee e e maiweighth th n n f o t spike grains and the yield per plant. There is a positive correlation between these two traits (r = 0.92***). The results illustrating the correlation between the number of productive tillers and yield per plant e givear n Figuro n . 5 eFroe diagra th s mcleai t ri m thae increasth t n i e e numbeth f productivo r e tillers entail e increase th yielsth r pe f do e plant n durui s m wheat.

51 60

30 TV 20 20 15 10 10 5

3 4567812 9 123 456789

25 II 20 _- - v 15 — 15 10 10 P 5 n n 5 nnn nfinnnn 123 456789 6789

III 20 VI 15 15 10 10 5 n Fi n „n n 5 „ 12J 4567Ö9 123 456789

Fig . 2 . Numbe d relativan r e lengt f internodeo h f o s control N788 (1) and mutants or mutant cultivars: Castelporziano (2), Cresso (3), 15/4-2 (4), Zeverjana (5), 720-C (6), Ambra (7), Losen 76 (8) 9 (9)an15 d , (1-st uppermost internode).

W r*<Ö ^a. 60 o 4) -\ J3 13 ''O <0H EO £ U 20 «t a R -^ 41 50 70 90 no 130 plant beight /cm/

Fig.i The relationship between plant height ana . *** . length of the last internode /r=0,98 /

52 20

20 18

18 16 16 ^ I/, 3 r-a*. *-» S I2 —I c. I0 ~ 10

123'« weight of grain of main spike /g/ X Kn i r e l l ti

Fig.e relationshiTh 4» p between weighf o t e relationsliFigTh .5 i \> between tillernu *< » grai f maio n n spik d yielan e d and yield per plant /r=0,85 / per plant /r=0,92***/

The increas e maith nf o espik e grains number resulte increasth n i s e of its total grain weight per plant. This is illustrated in Figure 6.

tn a a a

•H V

0 6 0 5 O A 0 3 0 2 numbe f graio r f u.aio n n spike

Fig.6. The relationslii p between number of grai f maio n n spik « graian e n * * * weight of main spike /r=0,87 /

53 From 1981 to 1984 comparative trials of mutant lines were carried out in 4 replications in 10 m^. The results are listed in Table 2.

Tabl . 2 e Grain yiel f semi-dwaro d f durum e periomutantth r dfo s 1981-1984 (yield in kg/ha and % of control)

1981 Mutants 1982 1 983 1584 Averag4 r fo e years l-^'/h: ? a „c/La ^ ^ kg/ha Je ke/ha % Luben 76 55i; 120,3** 5447 110,0** 4500 119,6»* 4030 11C,1»» 51D6 116, 3** Zever ana .CXu 100,1** y/20115,5** 3470 90 ,6 4090 S8,3 4582 104,3*

Ambra 5144 111,2** -,447110,0«-* 4461 ,5*C 11 * 3980 95,7 4753 108,3» 15/4-2 <,C3C 100,: 451091,1 2534 C6 ,2 4060 97, ß 3939 89,7 "0-C 5C11 102,;* jyo ', 20, O*-" 4970 129,6** 4940 110,7** 5215 118,7**

- 59 jC.. 3 10, ,j** ;320107,4* 3^13 ' » -•y 4020 ;6,£ 4507 102,7 r Control 4LJ3 100,0 .;9 j3 100,0 3830 100,0 4160 100,0 4392 100,0

*p 0,05 »*P 0,01 *** 0,00P/ 1

e averagTh el line al e yielgive ar f sn o percen di n n relatioi t o t n the control. The results obtained indicate that only the mutant line 15/4-2 is characterized by a lower yielding potential, the average 4 year yiel s 10.3i d % lower tha e ncontrol th tha e f otheo tTh . r lines exceee th d control by 2.7% to 18.7%. This indicates that lines with very high yielding potentia d beeha l n created. Among these lines 720-s i C characterize y extremelb d y high yield (5,215 kg/ha), which exceede th s contro y 18.7%b l . Loze 6 7 varietn y (5,106 kg/ha) which exceede th s control by 16.3% and Ambra (4,758 kg/ha) which exceeds the control by 8.3%. In 1982 the Lozen 76 mutant was approved by the State Commision as a variety. Mutant lin ew undergoin no 720-C s i a preliminarg ye triath t a l State Commission.

e proteiTh n content analyses were carrie t froou dm 198 o 11983t e .Th results s listea , n Tabli d , indicat3 e e that only Ambr s characterizei a d by lower protein conten - 3.1t %s compare a e controlth e o rest dTh f .o t the mutant lines o excee8.8%t e contro1 th ,d3. y whicb l h indicates that mutants wit a higheh r protein content have been obtained (16.60d an % 16.46%).

The results of the trials on resistance to cold of durum wheat mutants under controlled conditions are listed in Table 4. It can be seen that durum wheat mutants Lozen 76 and Ambra are characterized with a considerably higher level of cold tolerance with respect to the control - Zagorka (hybrid of durum wheat with Triticum aestivum) , which is a winter typee mutanTh . t lin ee earlisth Zeverjana f o t e maturinon , g durum wheats s alsi , o characterize a hig y hb d leve f colo l d resistance.

The results obtained indicated that semi-dwarf mutant lines have been created which are cold and lodging resistant and with a high yielding potential and protein content. The mutant lines Zeverjana, Ambra, 159 and 720-C have proven to be valuable cross breeding materials in durum wheat.

54 Table 3. Protein content of durum wheat mutant lines for the period 1981-1983

Mutant 1981 1982 1983 Average for lines 3 years Protein Relation Protn ei n io t Rela Protein Relation Protein Relation content to cent rol content o controt l content to control content to control (%) (7.) (7.) (7.) (7«) (%) (%) (7.1

Losen J6 17,72* 105,9 14,43* 107,9 14,96 95,7 15,70* 103,1 Zeve rjana 17,60* 105,4 14,30* 106,9 15,50 99,2 15,30* 103,7 Aabra 15,82 94,6 13,40 100,2 15,08 96,5 14,76 96,9 1 5/4-2 18,90** 11'3,2 14,90** 111 ,4 16,01 102,4 16,60* 108,9 720 - G 19,68** 117,4 14,76** 110,4 14,92 95,5 16,40* 108,8 159 16,85 100,6 14,65** 109,6 16,30* 104,3 15,93* 104,6 Control 16,70 100,0 13,37 100,0 15,63 100,0 15,24 100,0

* p 0,05 ** P / 0,01 #** p 0,001

Table 4. Cold resistance of durum wheat mutants tested in a cold chamber

Mutants Surviving plant s (%) and -11°C -14°C -17°C -20°C cultivars

Zagorka-control 96 41 4 0 Ambra 97 94 30 H Losen 76 89 74 31 11 Z evea an r j 97 86 20 0 72C - 0 07 85 17 0 159 100 57 8 0 1 5/4-2 94 73 26 4

They have very good combining ability and will be used for crossing with other high quality lines from Italy, France, Canad d wite besan ath h t lines from Prof. Konzak, USA. Hybrids obtained in an2 progenieF d s will be investigated for agronomic characters.

o increasT r e semi-dwarnumbeou th e f o r f mutant stoc f wheato k , seeds f localo , tall, cold resistant durum wheat cultivars have been treated with NaNß , EMS and gamma rays separately and in different combinations. s founwa t d I thae mosth tt effective chemical mutagenS EM e NaNd ar san ß , whe2% n use n combinationi d .

55 Four mutants and eleven cultivars of different plant height were analyse A responseG r fo o dsemi-dwar Tw . f durum wheat cultivars (Fai4 5 a d ) Zeverjanweran cm em 3 c 6 foun - ao posses t d s differen A sensitivitG t y [7]. The results of the genetic analysis showed that the semi-dwarf ing genes of varieties Faia and Zeverjana were allelic while mutants 15/4-2 and Ambra possess a different one, non-allelic, GA sensitive [5,6]. Genetic analysis showed that semi-dwarf mutant is independently segregated with locus.

Finally r studieou , s with induced semi-dwaff mutant f duruo s m wheat indicated also, that some height reducing genes have good potential applicatio n breedingi n .

e resultTh s sho e wmethod th tha f i f experimentato s l mutagenesie ar s combined with those of classical breeding a large variability of durum wheat can be more effectively and more rapidly created.

REFERENCES

[1] FILEV, K.A., 1981, "Utilization of induced mutations and gamma radiation in cross breeding of durum wheat", in: Induced mutation a too n plans i a ls t research, IAEA, Vienna, 504. ] FILEV[2 , K.A., 1981, "Correlation dependence between element f yielo s d in mutant hybrids and cultivars of durum wheat". Jubilee sessio 0 celebratio8 f o n f Acado n . PopovP . , Sofia, 181. [3] FILEV, K.A., 1981, "Induced mutations of durum wheat with useful biologica d economian l c characteristic". Proc. Geneticd an s Cytogenetic Plantsn i s , Sofia, 161. ] FILEV[4 , K.A., DONINI , 1982B. , , "Useful mutations induce durun i d m whea y gametophytb t d seean e d treatments". Proc. First Research Co-ordination Meeting on Semi-dwarf cereal mutants and their use in cross breeding, TEDCOC 268, Vienna, 65-72. ] FILEV[5 , K.A., 1984, "Inheritanc f culo e m heigh d graian t n yieln i d durum wheat", Second Research Co-ordination Meetinn o g Semi-dwarf cereal mutants and their use in cross breeding II, TECDOC 307, Vienna, 79-90. ] FILEV[6 , K.A., 1985, "Inheritanc f steo e m heigh 3 progenieF n i t f o s durum whead theian t r respons o t GibberelliI eI . Aß n International Symposiu f duruo m m wheat, Foggia, Ital n press)(i y . ] FILEV[7 , K.A., GENCHEVA, S.V., AVRAMOVA , 1985Z. , , "Investigationn o s stem heigh d gibberellinan t e sensitivit f mutantso y , lined an s cultivars of durum wheat. Plant Physiology, _7, 307-310. ] SCARASCI[8 A MUGNOZZA, G.T., BOZZ1N1 1968, ,A. , "Short straw mutants induced in durum wheat", Euphytica, 171-176.

56 THE EXPLOITATION OF THE TOM THUMB DWARFING GENE, ! HYBRIRht3,F N I D WHEATS

M.D. GALE, A.M. SALTER Plant Breeding Institute, Trumpington, Cambridge F.C. CURTIS, W.J. ANGUS Nickerson RPB Limited, Rothwell, Lincoln United Kingdom

Abstract

Nin hybridsj F e l wit al n ,Rhta h 3 dwarf female parent, were produced using the Shell chemical hybridising agent, WL 84811. Yield trials show that on average the yield potential of the Fjs exceeded that of the high yielding parent by 17 per cent. The increase in yield potential in the Rht3/rht hétérozygot s broughwa e t n increasaboua y b t n graii e n numbef o r 32%. The increased yields in the intervarietal F js were obtained by improved fillin t thesa g e extra grain sites o evidencN n .effeca r n o fo te tiller densit s foundwa y .

A close correlation between heterosi r planfo s t heigh d heterosian t s for grain yield was found between the hybrids which may provide a screen for rapid identificatio f higo n h yieldin combinations^ F g .

A cytological examination of tall 'off-types' among the F }S indicated the presence of a high level of aneuploidy in Rht3/rht hybrids. The cause d consequencean s f thio s s chromosomal instabilit e discussedar y .

INTRODUCTION

Wite adventh h f efficieno t t chemical hybridizing agents (CHAs)t ,i is now possible to produce sufficient F ^ hybrid wheat grain for large scale yield trials froy parentaan m l combination. Therefore n additioi , n to being abl o approact e e questioth h f whetheo n hybrid^ F ra e ar s realistic commercial proposition s possibli f t o i , e o explort eus e th e specific major genes which are of little value in pure line breeding programmes.

The major dwarfing genes in wheat, some of which are now known to have dramatic effects on yield components (review, Gale and Youssefian 1985), present many such possibilitie 1 hybridsF n i se suc On h. gens i e Rht3, which is usually considered to have too extreme an effect on plant height as a homozygote. However, it offers a number of features of potential value to the production of Fj hybrids. As a female parent, the yield of Fj hybrid seed may be improved because of its high spikelet fertility (Gal d Flinthaan e m e bette1983th d r )an pollinatio n achievey b d being surrounde y talleb d r male parentse hybridth e known I th ,. n

57 additive effec f Rhto t n reducino 3 g plant height will give semi-dwarf phenotypes with good lodging resistance. But perhaps of greater importance is the possibility that the effect of Rht3 in increasing spikelet fertilit s dominani y o thae hybris t th t d will have increased numbers of grain sites at which any hybrid vigour for improved grain size migh e expressedb t .

For these reasons a ,numbe f crosseo r s involvin n isogenia g c linf o e Rht3 in the variety Maris Huntsman as a female parent were made. A hybrid with Marls Huntsma s mad wa no establist e e effectth h f Rhto s 3 itseln i f the heterozygous condition. Hybrids wit a hselectio f otheo n r tall (rht) d semi-dwaran f varieties were mad o indicatt e e what level f heterosio s s could be expected when the effects of Rht3 and other sources of heterosis were combined.

MATERIALS AND METHODS

Genotypes

The female parent in the Fj hybrid production plots was Huntsman Rht3 (HRht3), an isogenic line derived at the FBI by six backcrosses to the tall parent from an F j between Maris Huntsman and Minister Dwarf, a source of Rht 3 .

e malTh e parents werl winteal e r wheat varietie d includean s d Marls Huntsman K varietU a , e Plany th bre tt a dBreedin g Institute (FBI); Stuart, Banner, Aquila and Ambassador, UK varieties bred at Nickerson RPB Ltd., (NRPB) d Merkur,;an Vuka, Nimbu d Oberstan s , German varieties l excepAl . t Ambassador, which carries Rht2, are tall, rht, varieties.

t graiF n production The Fj seed production blocks, which were grown at NRPB in 1984, consiste a numbe f o df female o r sm wid sow1 e n plot1. m i nlon y 4 b 2 gs between e samdrillth e f malo s e parent. Each male bloc s surroundewa k y b d e malth e f o paren m d separate 2 an t1 d from other male blockt leasa y b ts e femaleTh . m s 4 wer2 e sprayed wite Shelth h l chemical hybridizing agent (CHA L 84811W ) , azetidine-3-carboxyli ce optimu acidth t a ,m growth stage and dose rate. Yields of F ^ grain were about 12 kg per plot. The absence of grain set on ears within the HRht3 plots bagged before male pollen was available and the absence of Rht3 homozygotes in the Fj yield trials indicated thae degreth t f selfino e s essentiallwa g y zero.

yiel! F d trials

Four trials were carried out in 1985, two at the FBI and two at NRPB. At each location one trial was given the complete current NIAB/ADAS recommended prophylactic fungicide, herbicid d insecticidan e e treatment (sprayed othee s untreateth wa rd )an d (unsprayed).

All the trials employed lattice designs with three replications at the FBI and two at NRPB. All plots were approximately 6 m x 1.16 m and the grain yields obtaine e expressear d s percentagesa d relative th o t e e contromeanth f o sl varieties Aquila, Avalo d Normanan n .

58 At the P3I the plots were scored for plant height (cm to tip of the ear), tiller density (no. fertile ears in a 30 cm quadrant across the drill), anthesis time (estimater cenpe t0 5 anthe s a d r extrusioe th n i n plot) ,e weelodgin on a scalk 9 n befor0- e(o g e harvest), 1000 grain weight (estimated fro0 grainsweighe 25 th m f d o tct-amylas )an e levels (extracted from wholemeal flour and expressed in mU/g by calibration with the Phadebas (Pharmacia) method). Frox randosi m m single leading tillerr pe s plot, estimates were obtained for tiller yield, spikelet number per ear, grain number per ear, total tiller mass, non-productive (vegetative) tiller masd tillean s r harvest index.

RESULTS

e 'sprayedTh ' trials were carrieo estimatt t e ou potentiad th e l grain yield of the Fj hybrids, while the 'unsprayed1 trials estimated performance when disease was not controlled. Both sites showed high level f mildewo s , Erysiphe gramini d Septorian s a tritici, e attackth t A . FBI a late attack of brown rust, Puccinia recondata, may also have reduced the 'unsprayed' yields.

The Fj combinations tested allow (i) observation of the effects of Rht3, as a hétérozygote, unconfounded by other sources of heterosis in the isogenic HRht3 x Marls Huntsman Fj, (ii) observation of the levels of heterosis obtained over a sample of seven different tall parents in the presenc f Rht3/rhto e d (iiian , n indicatio)a w Rht3/rhtho f o n , rht/Rht2 varietal hybri s mighFj d t perform froHRhte th m x Ambassado3 p F r

Yield in the 'sprayed' trials

The results are shown in detail in Tables 1 and 2 and estimates of heterosis are shown in Table 3. The yield data for the parents and FI hybrid s alsi s o show n Figuri n . 1 e

The grain yields indicate that the Rht3 allele as a hétérozygote may directly effect yields. The net effect of 3.7 per cent grain yield advantage over Marls Huntsman seen in the HRht3 x Huntsman Fj, although nonsignificant, was derived from major changes in ear conformation, i.e. an increase in grain number per ear of 44% with a concurrent decrease in grain weigh f 18%o t o .effecN n tilleo t r densit s evidentwa y .

S betweeFj e e seveTh n th HRht nd an 3tal l varietie l produceal s d higher yields than either parent, even whee yielth n d potentia f HRhto l 3 is considered to be that of Huntsman itself (Table 1, Figure 1). This was necessary to avoid comparisons involving HRht3 which performed extremely poorly in 1985. The heterosis figures range from 10% to 35% relative to 4% for HRht3 x Huntsman Fj. The yield component analysis on tiller samples froe samth me plots clearly show e sourcth s f theso e e increase n yieldi s . Increases in grain numbers are similar for all FjS, including HRht3 x H, indicating that thi s mose effecti s th t o likelt f Rht3o s e du .y Grain size, however behaves quite differently in the intervarietal hybrids. The heterosis values for grain size are -18% for the isogenic cross and -5% ovee intervarietath r wit, e resuljs th hF l t HRhtt rh thae meax 3th tn heterosi r singlfo sr graiea e n yiel s increasei d o 31%t d .

e biomasTh s data indicates that heterosi r graifo s n sizs i e associated with heterosi r planfo s t siz e intervarietae Th (Tabl . 1) e 1 F l hybrids are taller, relative to the mid-parent, and have increased straw

59 Tabl. 1 e Yiel d yielan d d related character n parentai s, hybri F d dan l 'sprayed ' trials

Mean plot yield Height Tiller yield Vegetative Grain No. 1000 grain a-Amylase % contrôla • cm2 (g) tiller yield (ear) weigh ) leve(g t l (mU/g) J Huntsnan 89 .8 112.0 2.53 2.62 41 .0 57.8 61.5 f l HRht3 x U 93 .1 84.7 3.06 2.43 58 .9 47.5 19.5

Merkur 92 .1 116.7 2 .58 2.80 44 .5 52.1 19.3 F! IIRht3 x M 112 .7 91.7 3.34 2.69 52 .0 52.0 39.0 Aquila 100 .8 112.7 2.07 2.41 39 .3 50.0 4.6 F! HRht3 x Aq 109 .9 90.7 3.05 2.46 52 .3 51.6 9.0 Vuka 87 .9 133.0 2.76 3.47 47 .0 53.6 2.7 ; HRhtF V x 3 106 .1 94.0 3.48 2.94 61 .3 54.2 14.5 Banner 78 .3 97.3 2.05 2.01 49 .5 37.0 2.4 F- HRhtB x 3 110 .2 88.3 3.14 2.63 63 .9 46.6 12.1 Stuart 88 .5 109.0 2.75 2.91 53 .2 50.0 6.1 F- KRhtS x 3 116 .2 90.7 3.16 2.62 56 .5 52.4 18.3 Nimbus 81 .5 114.3 1.94 2.42 40 .3 46.4 3.5 ; HRtltF N x 3 98 .4 92.0 3.02 2.73 56 .3 49.1 12.4 Oberst 81 .8 118.3 2.19 2.70 44 .5 44.1 2.6 F ; HRh 1 3 x 0 94 .7 90.7 3 .16 2.62 62 .2 45.8 6.7

Ambassador 95 .8 91.7 2.43 2.13 54 .3 42.5 29.0 F : HRht3 x Aa 96 . 4 73.3 2.81 2.16 56 .6 46.3 42.3

HRht3 64 .3 59.7 2.55 2.06 52 .5 46.9 41.5 SED 4.36 204 0.182 0.272 3.49 1.53 ex (.44)

rht parents (aean)1* 87 .2 114.5 2 .33 2.67 45 .8 47.6 5.9 HRht3 x rht F-s (mean) 106 .9 91.2 3.19 2.67 58 .9 50.2 16.0 SED 2.12 .77 0.069 0. 1C3 1.32 0.58 e* (.17)

Notes

1 Yield figuree ar s means ove3 r replicates at FBI and 2 replicates dt

NRPB, relative to the means of Norman, Avalon and Aquil,i checks at

NRPBt a h" . t d 7.03an I FB t a ' bot ~ h h t • 8.4sites 60 10 . 1

2 All remaining data from FBI trial only.

3 a—Amylase analysis carried out on loge transformed data.

e meaTh n figure 4 e obtainear s d froe seveth m n intervarletat rh l

parents and F[S, i.e. excluding Huntsman and Ambassador.

60 Table 2. Tiller density, anthesis date and spikelet number per ear in

parent, F d an s hybrids in fungicide treated trial

Tiller No. Anthesis Spikelet No. (m~2) date (days) (ear)

Huntsman 472 2.0 19.3 F! HRht3 x H 469 1.0 19.8

HRht3 403 0.0 19.0

Other parents (mean) 1 532 4.8 21.8 F! (mean) 1 460 1.3 21.0

SED2 38.3 .70 .54

Notes

1 Parental and Fj means obtained from all intervarietal hybrids.

2 'SED' applie o differencet s s between mean d singlan s e genotypes.

Table 3. Estimates of heterosis in FI hybrids in fungicide treated trials

i combinatio F n Mean plot' Height2 Tiller Vegetative Grain No. 1000 grain . HRht.. x 3 yield ' yield tiller maes per ear weight

Hunt sman +3.7 -4.6 +21.0 -7.3 +43.7 -17.7

Merkur +23.9 +12.3 +30.7 -0.7 +39.4 -5.3 Aquila +15.3 +17.0 +32.6 -2.2 +30.3 -4.2 Vuka +19.4 -6.4 +31.6 -3.4 +39.3 -2.6 Banner +31.1 +52.2 +37.1 +13.6 +41.2 -1.7 Stuart +30.3 +25.8 +19.7 -5.2 +20.0 -2.8 Nimbus +14.3 +18.4 +35.1 +8.32 +38.5 -5.6 Oberst +10.4 +5.8 +33.9 -1.5 +45.5 -11.1 Ambassador +3.9 -15.0 +13.3 -10.03 +18.8 -7.6

SED3 4.6011 5.28 6.59 10.73 6.56 3.13 t ! HRhtF rh x 3 +20.7 +17.9 +31.5 +1.37 +36.3 -4.8 SED11 3.48" 3.93 4.90 8.11 4.96 2.37

Notes

1 All values, except those for [>lant heighit, calculateI s a d 'l/((Huntsman + male parent)/2)X. Thui the values for the HRht3 x Huntsman hybrid measure the effects of Rht3 In the heterotygous «täte, while in the other hybrids the values measure the heterosis in a Huntsman z F2 hybrid la the presenc f Rht3/rhto e .

The value r planfo s t height have been obtaine s deviationa d s abou midparene th t t (-0a scal n )o e of HRht +100• 2 -10» 3P .d 0an

3 SED (calculated as /(EMS/nj + EMS/n2). lOVx where nl and n2 are the number of replications in the means and x • grand mean) applies to difference2 s in heterosis estimates between hybrid combinations.

4 SED applies to differences from the mean midparent value (see notes 1 and 2).

61 123

X 110 h X X x o: X X X X X X x X o ICO X X X X X LJ X X X X x X X X X X X" X X 90 \ [T, X x X x X X X X X X x X X a X X X X X X X X X X X X X X X X X X X X X X X X X X X. X X X X X X X X < et: X X X x x X x X X x X 50 X ce 1- »- x ce X X 3 X ce x X X Lu t— 1 ^ et X CD X z z o X 85 X t- X =Sj X X X X •< x * x k, =- x o x z x m x t i t Rhtrh * 3 * Rht2

Note. The open bars are pure line varieties and the hatched

bars the Fl hybrid of that variety with HRht3. The LSD 5% for parenta j hybriF v l d difference s 8.6%i s .

Figure 1. Parental and F^ hybrid yields.

weights relativ e meanth f Huntsmao e so malt eth e d parenan n t even though plant heights are reduced by 14% overall due to Rht3/rht. Observation of tiller density data indicates that this is not a factor involved in the heterosi r yieldfo s . Indeed e meanth , s show n Tabli n 2 indicate e that high tiller numben almosa s i rt completely recessive charactee th n i r limited number of hybrids included in this investigation.

Anthesis data shows simple dominanc r earlinesfo e d spikelean s t r shownumbeea o dominancer n s pe r . Neithe f theso r e characters appeao t r be contributory factore increaseth o t s d yields demonstrate^ F e th y b d hybrids.

The hybrid involving the semi-dwarf male parent Ambassador showed little promise, possibly because the spike fertility was already high due to Rht2 and because the vegetative biomass, although not further reduced t havno e y beee ma shor ith , n F^ tadequat o support e e graith t n filling t e hybridsHRhtfounrh th x 3n i d .

The association between plant size and grain yield in F^s

s noteA d above e increaseth , d grain e hybridyieldth e n i sar s obtained on relatively larger and taller plants. Reasonable positive correlations were obtained between heterosi r yiel d heterosifo s an d r fo s vegetative tiller weigh = .68 = .063r ( t,p d grai )an n = .75siz = r ( ep , .034), however the closest relationship was achieved using the plant height data. Figure 2 shows the relationship between heterosis for height (as calculated and shown in Table 1) and heterosis for yield. The correlation is r = .91, p = <.001.

62 140 r-

TJ 130

L 120 O

0) W l 10 o L QJ

01 r-, 915 100 -

90 _L _L _L J 0 6 0 5 0 4 0 3 0 2 0 1 0 0 -1 0 -2 0 -3 Heterosi r hQighfo s t

Note. Heterosis calculate s describea d n Tabli d . 3 Yiele d an d

height data taken from FBI sprayed trial only.

Figure 2. The relationship between heterosis for plant height and

heterosi r yielfo s d among nin hybrids^ F e .

q-Amylase levels

e a-amylasTh e levels were generall e y198 th hig K harves5U n i h t because of the cool, wet, grain ripening conditions. In these trials the the preponderance of Huntsman 'genes' increased levels still further, Huntsman, and some other UK varieties, characteristically producing a-amylase before maturity even in the absence of visible preharvest sprouting (Gale, Flintha d Arthuran m , 1983).

The Rht3 allele, however, tends to reduce a-amylase in germinating grain because it confers relative insensitivity to gibberellin upon the aleurone cells (Gal d Marshallan e , 1975) e allelTh . e cana s ,a homozygote, reduce enzym a sproute n i e % leveld77 croy b s p (Flinthad an m Gale, 1982). Of course, the grain on an Fj crop will segregate as an F2 for endosperm, characters e Rhtth 3 d allel,an e wil presene e ratib l th on i t 3 doses doses2 ;triploie dose1 th 0 dos: n :i e d aleurone tissue.

The enzyme levels shown in Table 1 demonstrate that the FjS generally fall belo e midparenth w t calculated from Huntsmae malth e d an n parent, and are related to the male parent level. This may reflect an effec f Rht3o t , howeve e advantageth r n termi s f breadmakino s g quality would be slight.

The levels found in HRht3 (41 m U/g) are unexpectedly high compared with thos ee talle founth n i rd heterozygous genotypes e explanatioOn . n may be that the moisture levels in the HRht3 stand were even higher than elsewhere, because the ears were close to the ground and were protected from any drying wind by the surrounding taller plots.

63 Yield in the unsprayed plots

The mean values and levels of heterosis for grain yield and yield components are shown in Tables 4 and 5. The yield data are summarised in Figur. 3 e

Tabl. 4 e Yield and yield related characters in hybrids between HRht3 and Huntsman, seven tall varieties and Ambassador, an Rht2 semi-dwarf in unsprayed trials'17

Mean plot yield Tiller yield Vegetative tiller Grai. no n 50 grain I controls (g) yield (g) (ear) weight (g)2

Huntsman 101.2 2.18 2.35 44.8 2.44 ?l HRht3 x H 84.2 2.17 2.10 58.1 1.87

Tall parents (mean) 98.5 1.72 2.26 43.7 1.96 HRht3 x FJB (mean) 94.3 2.35 2.48 58.7 1.99

Ambassador 106.9 1.78 1.84 56.3 1.59 F, HRht3 x Am 82.3 2.45 2.18 59.8 2.06

HRht3 51.3 1.89 1.84 50.3 1.88

SED (l)3 5.55 0.210 .167 3.57 0.141

SED (ii) 4.19 0.159 0.128 2.74 0.108

Notes

1 Aa in Table 1, the yield figures obtained from both FBI and NRPB trials and the component data fro^ FBI trial only. 1 Yield figures relative to 'unsprayed' treated control means.

2 Grain weights calculated from sampled ears.

) applie(i C o differencet SE s 3 s between single genotypes, (ii) applie o differencet s s between aear.s and single genotypes.

Tabl . 5 eEstimate f heterosio s j hybridF n i sn unspraye i s d trials

F| combination Mean plot Tiller Vegetative Grain grai0 5 n HRht3 x ... yield' yield tiller yield No. weight

Huntsman -16.8 -0.5 -10.6 29.7 -23.4

rht Parents (mean) -5.4 +19.3 +7.8 +32.7 +9.0

Ambassador -20.9 +23.7 +4.1 +18.3 +2.2

SED 6.34 + 7.62 +5.55 +5.11 +5.3

Note

Calculation n Tabli d SED s . an sa 3 es

64 12C

- X — X 1 — o; X l 30 - X — •^ X 's X -r; X — X -^ X - X X X X X

_ X X X X X X x X X X

S X X X X X X X X X X X X X X X X X X X X X X X X X \ X X X X X X X X ce X X X. X o X z X X X X a X X x X X X X m X x ^ ce 1— X \— LO ce CO fif CO ZJ K CO LU t— X X X X ce x X X CO X 1 ce r> 1 LU CO X o X LU x X X CD X i X X X z m T. x x •x. x L/5 x > x O x x x iX. r • i 1 J 1 1 Rht3 * rht Rht* 2

= 12.7% % 5 Note .D s FigurLS A . . 1 e

Figure 3. Parental and F1 hybrid yields in unsprayed trials.

In those conditions the hybrids are generally less productive than the pure lines although the intervarietal F^s are relatively higher yielding than the HRht3 x Huntsman F ^. The yield components and heterosis values rank similarly to those obtained in the sprayed trials, but all at less productive levels.

This may not reflect the performance of all Fjs under these conditions and, indeed, conflicts with results obtained witii othes F^ r n 198i I 5FB whertrialle e th e t levela d f heterosio s s were generally higher in the unsprayed plots (J. ßingham, pers. corum.). The male parents were not selected for their levels of resistance to disease and were particularly susceptible to mildew. In addition, the common female parent has little to offer in terms of dominant genes for resistance to e diseaseth f o sy encounteredan n additioI . e shorth n t statured Rht3/rht and Rht3/r_ht, rht/Rht2 F ^ may have succumbed more rapidly to the severe e splasattacth f ho k transmitted Septoria tritici thae talleth n r pure lines.

Chromosome stability

A feature Rhtth 3 1 f hybriF o e e th e presencd l th tria al s n wa li e plots of between three and 2Û tall plants, at least 20-30 cm taller than th e stand th bul f o .k

Ears from these plants were harvested separately e grainth , s germinate e rooth t d tipan d s score r chromosomfo d e e plantnumberth l sAl . scored were shown to be monosoinic, i.e. to have 41 rather than the euploid 2 chromosomes4 e explanatioTh . e talth l r plantfo n s mus e thab t t they represent raonosomic r chromosomefo se locatio e th Rht th , 3 f 4A o genen . Monosoraics which have lose homologuth t e derived froe talth ml parent will

65 still be dwarf, although probably a few centimetres taller than euploid plants, but the half which have lost the 4A chromosome derived from HRht3 will be tall, taller in fact, than a euploid rht/rht.

The conclusion that the raonosomy occurred due to instability in the developing F1 grain, is supported by the observation that two height classes of tall raonosomic plants were observed in the HRht3 x Ambassador e Fshorte Th I- r clas s consisteni s t wit D hchromosom4 monosome th r fo ye carrying Rht2 derived from Ambassador while the taller class were presumably A deriveraonosomic4 e th d r frofo s m HRht3. t cleano rs i whethet i l t chromosomeal rye s s A unstabla A e 4 ar ss a e and 4u in Rht3/rht hybrids. In some Rht2 semi-dwarf pure line varieties where similar tall monosomic e appearancr chromosomth fo s e r th ma f D o e4 e stand, there is some evidence that this single chromosome is that most likele lostb o t .y Howeve e level th rt 0.131/ a f monosomo s D 4 ir fo y (Worland and Law, 1985) are some ten times lower than observed for 4A here.

CONCLUSION

The yield levels of the seven intervarietal F js Incorporating the Rht e heterozygou3 th gen n i e s stat e encouragingar e e meaTh .n figuref o s 20.7% over the midparent, or 16.7% over the highest yielding parent, were obtained in trial conditions which are likely to give a reflection of yield potential e actuaTh . l level f yielo s d were high (9.04 tonnes h"1) d highean r thae checth n k varieties f whico l e Nationahal ,th wer n o e l Institut f Agriculturao e l Botany recommended lisy b f varietieo te us r fo s farmer n 198i s 5 (Anon, 1985). t withstandinno Thi s i s e facth gt that many e varietieoth f 1 combinationF e s th use n i d s were either rather old, such as Marls Huntsman which was released in 1971, or not bred and adapted for e Germath l n al K conditionU e varietiescasr th fo es i t s seemI a s. s likely therefore that, with more modern parents, especially those with improved level f diseaso s e resistance, even greater yields coule b d obtained t shoulI . e saidb d f courseo , , that such tall parent y havma s e e bretb o d especiall n Rht3/rha r fo yprogrammj F t e becausK U e e th mos f o t varieties released sinc mid-1970e th e s carr e Rhtth y2 semi-dwarfing gene.

The source of the yield increases were similar in all the Rht3/rht F ^s . Increased spikelet fertility (+36% over the midparent) was introduced by the single Rht3 allele and then the generally improved vigour derived from heterozygosity elsewhere, reflecte n improvei d d size e hybrids th d mas an n i s availabl wa , o file t extre th l a grains set. Thus o evidencthern s i e e here that developmental event r timino s e affectear g d in FjS l improvement.Al e consistenar s t with faster growth rates throughou e plantth t .

f Rhto Thie 3 us sdemonstrate s that parent e designey b hav ma o st e d and bred especially for use in F j hybrids. Here we have specifically improve e yielon d d component, i.e e numbeth . f graio r n sites o thae s , th t hybrid vigour nay be channeled into grain growth rather than vegetative growth. Other major genes which effect developmen y havma t e similar potential.

The effects of Rht3 on plant height represent another "design feature n thesi 1 e FjS. Hybrid e oftear s n relatively tall because minor genes effecting plant height are usually dominant for tallness, and as see e HRhtn th here highes x 3Bannen th i e , j tF r yielding combinations will

66 produce the tallest F1 relative to the parents. Thus, hybrids between Rhtl or Rht2 semi-dwarfs and rht genotypes will usually be too tall and prone to lodging. Even horaozygous Rhtl or Rht2 (or the double hétérozygote Rhtl/rht, rht2/Rht2 which has the same effect) produced by crossin o serai-dwartw g f varieties wile higth lho talr ofteto fo le b n input husbandry employeK acreageU e th n muco df . o h Three allele hybrids, e.g. Rhtl/Rhtl, rht_2/Rht2, provid a similae r solutio o that n t reached with Rht3, howeve e breedinth r f suitablo g o gentw ee dwarf s parenta s y ma s present more difficulties than the incorporation of a single Rht3 gene.

The hybrids tested here provide little information on the breadraakin e Huntsmath g f qualito e expectenb e us o t y e n Fi \sTh d • varietal backgroun s raiseha d d level f oramylaso s e hybridth n o i thaes s t y adversan e effect f 'vigouro s n thio 1 s characte y havma r e been obscured. e samth e r reasoFo y beneficiaan n l effecte GA-insensitivitth f o s y introduced with Rht3 may also have been obscured, however the fact that j croths F segregatin ewa pe graith n o nr Rht fo g3 will reducs it e efficiency by at least 50% anyway.

Among the correlations between plant characters and the expression of heterosi r yieldfo se relationshith , p with plant height (relativo t e the parents) is particularly encouraging and may provide the basis of an early scree r higfo nh yielding combinations. This character canf o , course e gathereb , d fro mw plants onlfe a y , which coul e growa b d n i n glasshouse out of season. Work is in progress to assess the value of this relationshi n otheri p , non-Rht3, hybrids.

e majoTh r disappointment surrounding these experiments, wit a hvie w to the commercial exploitation of Rht3 in F^s, is the presence of tall raonosomics in the stands, at levels much higher than allowed by the EEC standard f purito s r conventionafo y l varieties. More wor s requirei k o t d determine the source of these aneuploids, but at present the possibility tha a direct t e GA-insensitiveffecth f o t e dwarfing gen n chromosomo e e s cannoFj los e n ruleb i st d out.

We conclude, however, that the high levels of heterosis for yield combined wit n ideaa h l plant heigh o providt t e lodging resistance make Rht a 3realisti c commercial propositio r hybrifo n d wheat e genTh .e must first be incorporated in high yielding tall backgrounds with improved quality and disease resistance characteristics. These hybrids made with modern tall genotypes, again probably bred especially for this purpose, will demonstrat e fulth el e yielextenth df o tadvantage e gaineb o n t si d Rht3/rht Fj hybrids.

ACKNOWLEDGEMENTS

e gratefu War . eB.P Dr . o t lForste r carryine cytologicafo rth t ou g l analyses, and to Mr. John Bingham and the FBI wheat breeding team for conductin yiele th g d trials.

67 REFERENCES

Anon (1985). Recommended varieties of cereals 1985, Farmers Leaflet No. 8, National Institute of Agricultural Botany, Cambridge.

Flintham, J.E. & Gale, M.D. (1982). The Tom Thumb dwarfing gene Rht3 in wheac . ReduceI . d preharvest sprouting damag o breadmakint e g quality. Theoretical & Applied Genetics 62, 121-126.

Gale, M.D., Flintham, J.E .Arthur& , E.D. (1983). a-Amylase production i n the late stage f graio s n developmen n 'earla - t y sprouting damage* risk period n 'Thiri ? d International Symposiu n Preharveso m t Sproutin n Cerealsi g s J.EEd ?. Kruge d D.E an ra Berge .L , Westview Press, Boulder, 29-35.

Gale, M.D. & Marshall, G.A. (1975). The nature and genetic control of gibberellic insensitivit n dwari y f wheat grain. Heredit , 55-6535 y .

Gale, M.D. and Youssefian, S. (1985). Dwarfing genes in wheat. In 'Progres n Plani s t Breeding '. G.E VolEd ., .1 Russell , Butterworths, London pp 1-35.

Worland, A.J. and Law, C.N. (1985). Aneuploids in semi-dwarf wheat varieties. Euphytic , 317-32734 a .

68 COMPARISON OF TWO SEMI-DWARFING GENES ON YIELD PERFORMANCE OF DURUM WHEAT LINES*

B GIORGI Divisione Tecnologie Biologich Agranee , ENEA-FARE, CRE Casaccia, Rome, Italy

Abstract

To evaluate the effects of two different semi-dwarf ing gen^s n yieldo o cultivartw , f duruo s m wheat bre t ENEa d A were used. "Creso" has the Rhtl gene and is insensitive to gibberellin at seedling stage. "Tito" has reduced stature due to a semi-dominant semi-dwa^f ( 3D 1 mutation s gibberelliinducei d an y gammb dy ra an responsive. Sixty-six F randomly selected lines coming from the cros^ o* the above mentioned varieties were compared in agronomic trial^. ia! * of them were gibberellin insensitive , like Creso and half gibbers] it responsive, like Tito. Grai D lineS s highene wa syielth f ro d tha Rhte n th thal f o t lines, even though the difference was relatively small and no1 ^ e subsequen icantth f n I . e best th generationt F performin d an F s g lines ofihes semi-dwaro tw t f type e saverag th gav e n sano etn e e y^^ld results; thus showing thae reduceth t d height mutation (SDl appears e Rht th s gooa ls a dgen r breedinfo e g purposese b .o t However s ^a t i , taken into account thae differencth t plann i e t heigh n favoui t f o r e talleth D lineS r y compensats ma e Rht) (abouth cm l r 5 effec1 fo te ^ e positivbaseth n o d e yield-plant height correlation.

Introduction

The wheat production areas covered by semi-dwarf varieties e increasinar g yea y yeab r r worldwide spreaa th f o o dt ee .Thidu s i s

few height reducing genes, among which those deriving from Norm 10

appear to be the most relevant. Whether the great success of such genes

ia fortunats o simplt e du y e o thei t cas r ro e pleftropic effectn o s yield in addition to the benefit deriving from lodging resistance is

stil n opea l n issu e inductioe th (I). t Ye f reduce o n d height mutants

* Contribution No. 118 of the Divisione Tecnologie Biologiche e Agrarie, ENEA. This researc s carriewa h t undeou d r IAEA Research Agreement number 2687/CF.

69 in whea f boto t he throug us physica e th hd chemicaan l l mutagenic agents is relatively easy (2). Such circumstances offer the possibility to

evaluate geneti s */ela cs environmentaa l l interaction f plano s t height

reducing genes comng fron different genetic sources (3).

Suitable material for this kind of investigations resulted

froe dururth n r wheat breedin n latgi prograep u 1950' t se mt Casacci a s a

Nuclear Center undee Italiae aegith th rf o sn Atomic Energy Commission

(CAEN ) .

Material d Methodan s s

o semi-dwarCrestw d Tite an oar o f wheat cultivars released in 197 d 19764an , respectively (4) Rhte e forme.th lTh s genha r e which

markedly reduces plant height, whereas the latter has reduced stature

because of a semi-dominant SD (Semi-D^arf) mutation induced by gamma

rays liabl• ) I e

TABL Plan- I E t height, grain yiel d tesan dt o weightw f o t

durum wheat cultivars. (Average 0 agronomi8 f o s c

trials carried out in Italy for 8 years)

CULTIVARS PLANT HEIGHT GRAIN YIELD TEST WEIGHT

cm q/ha kg/hi

CRESO 75 58.83 81.95

TITO 87 58.43 77.37

4 tallem 3- dayc d 5 s1 an r late - 0 1 rTit s thai o n Creso

r emergenciea n e time. FurthermoreT Tito shows good cold resistance, elastic culms and high yield potential. In some areas of Central and

Northern Italy Tito can easily outyield Creso. However, it presents

also some weak points, being susceptibl o bott e h leaf rusd powan t -

dery mildew. These diseases are rather endemic in Italy, but represent

70 a high risk factor which accounte disappointinth r fo s g performance

of Tito in terms of yield and test weight in some circumstances. To evaluate the effects of the two semi-dwarfing genes on

other characters, particularly yield e cultivarth , s Cres d Titan o o

were crosse e progenie th n 198 i dd 0an s were analyze e followinth n i d g

years according to the procedures described previously (,3).

Field trials initiated with F lines selected only for 3 J gibberellic acid response. By using the gibberellin test, consisting

in growing germinated seeda solutio n i s r n fo wit 0 p.p.mA 1 hG f o .

8 days6- , three group F plantf o s s A>ere identified

1 - Homozygous GA - Insensitive semi-dwarf plants fRhtl/sd). ~ ' — 3 Homozygou- 2 Responsiv- A G s e semi-dwarf plants (rhtl/SD). 3 ——— Homozygou- 3 Responsiv- A G s e tall plants (rhtl/sd).

Assuming that the frequency of both useful and detriments' genes 3^

homogeneously distributed in the three groups of plants as clis^f:e1

above y differencan ,meae th n n value: e s amon e groupe b th gn ca s

reasonably attribute e e specifiactioth th f o o nt d c genes affecting

plant height. Starting wit F hseed a sspaced-plante d field experiment

based on a total of 80 F families replicated 5 tines //as cair:ed out.

However a bette r fo ,r appraisa e t\uoth f majoo l r semi-d//arfing genes

on yield and yield components, 33 Creso-like and 33 Tito-lik<= F lines 4 were compare a fiel n i dd triale control th l line Al d . an ss ~es(d în o

r> 2 Tito) were sowm plotn (1. 3 i n) accordin ionz^? n f 5 o sx ra a d o t g

complete block design with 3 replications.

Climatic conditions were nearly normal ior wheat product or

in Central Italy. Shortag f raio e n occurre n Apri i dd May t an l ,bu

the grain yield was only slightly affected. Diseases and pests /

In the subsequent years the number of lines tested was

restricte e betteth o t rd yieldin F ge generatio onesth n I . e th n tota decreaselt i , wherea numbe. However14 F 11 s n o i wa rst d a , 6 balance between the semi-dwarf types ^as maintained. For the last

71 o generationtw 0 1 wite plote sam th s e sizth h e wa sf th s o e randomi -

zed complete block design wit replications3 h .

Results and Discussion

The results obtaine dF familiefroe th m s showe a smald l 3 advantage in yield per plant for the gibberellic acid insensitive

(GATi progenies over the responsive semi-dwarf types. In the F

generatio e grai - responsivD lineth n S A ne (G syiels th wa f o d) e

significantly higher thae Rhtth nl - insensitive)line A (G s , even

though the difference was only 200 kg/ha (Table 11). The SD lines

showed also a higher test weight as compared with the Rhtl lines,

whi^ e oppositth e e situation occurre r Tit. Cresofo dvs o .

TABLE II - Performance of random selected F lines coming from 4 the cross CRES x TITO O

^^N. PARAMETERS N° OF PLANT EAR GRAIN TEST

F HEIGHT EMERGENCE YIELD WEIGHT 4 GENOTYPE. ^v S LINES cm DATE q/ha kg/hi

CRESO (Rhtl/sd) - 84 3 . MA9 Y 64.1 82.4

TITO (rhtl/SD) - 103 ** MAY 10 64.7 81.4

F LINES (Rhtl/sd; 33 84.3 6 . MA8 Y 63.0 80.6 4 F LINES (rhtl/SD) 33 102.6** * 1 MA9. Y 65.0* 82.2* 4

* Significantly different at P ^ 0.05

** Significantly different at P < 0.01

The plant heigh e f correspondinCreso ttn d tha an f oo t g

Rhtl line d 84. respectivelyan , e averags 3m cm th werc n 4 o e8 e .

Tito and SD lines were taller (103 cm and 102.6 cm, respectively).

All the genotypes tested showed an increase of the plant height

in respece valueth o t s obtaine e previouth d s year e differenTh . -

72 ce between Creso and Tito was also greater: 19 cm against 10-12

cm as normally occurs. The results obtained from the comparison of the best 7

lines from each group showed that the yield potential of the F 5 selected lines was higher than that of the best control, irrespective of the presence of the either semi-dwarfing gene (Table 111).

In particular the F Creso-like lines yielded 64.9 q/ha, whereas

the Tito-like plants reached 63.1 q/ha. However, the difference

of 180 kg/ha was not statistically significant. Test weights were

similar.

Performanc- TABL I II E 4 selecte1 f o e F dline s coming froe th m 5 cross CRES x TITO O

PARAMETERS N° OF PLANT EAR GRAIN TEST

F HEIGHT EMERGENCE YIELD WEIGHT

GENOTYPES LINES cm DATE q/ha kg/hi

CRESO (Rhtl/sd) - 83 MAY 17.5 56.3 82.6

TITO (rhtl/SD) -* * 1 10 MAY 20.5 59.0 80.1

F LINES (Rhtl/sd) 7 82.9 MAY 16.4 64.9 81.3

F LINES (rhtl/SD) 7 95.4** MAY 18.4 63.1 81.6

** Significantly differen 0.0< P 1t a t

Following the same testing procedure, 6 F lines (Rhtl/sd) were — — —— 6 compared witF 5 lineh s (rhtl/SD) e chose.Th n lines were only 6 ~~ ~" thos ee previouwhicth n i h s year yielde t leasa d 0 q/ha6 t . Here

again the two groups of lines behaved quite similarly (Table IV

and V ). The yield response of the control varieties Creso and e lasth Tit tn i ofiel d trial deserve a specias l commentA .

dramatic collapse of the cv. Tito in terms of yield and test

weight took place. It gave only 43.2 q/ha as compared //ith the

73 TABLE IV - Performance of 11 selected F lines coming from the 6 cross CRES x TITO O

PARAMETERS N° OF MILDEW LEAF RUST GRAIN TEST

F Scale Scale YIELD WEIGHT 6 GENOTYPES LINES (0-9) (0-9) q/ha kg/hi

CRESO (Rhtl/sd) - 4 0 63.5** 84.4* '

TITO (rhtl/SD) - 9 7.5 43.2 79.4

F LINES (Rhtl/sd) 6 6.4 3.7 54.1 81.5 6 F LINES (rhtl/SD) 5 7.4 3.9 54.3 82.1 6

Significantly differenP t a t

TABL - Summare yiel V th E df o ydat a from short straw lines from

the cross Creso x Tito, differing for two semi—dwarfing genes.

LINES Rhtl/sd LINES rhtl/SD GENERATION CRESO TITO

q/ha q/ha No. Yield No. Yield

q/ha q/ha

F 64.1 64.7 33 63.0 33 65.0 4

F 56.3 59.0 7 64.9 7 63.1 5

F 63.5 43.2 6 54.1 5 54.3 6

MEANS 61.3 55.6 60.9 60.8

74 63.b q/ha produced by Creso. As to the test weight a difference

kg/h5 s observef o wa i d (Table IV). Suc behavioua h o doubn s i rt

related to both disease attacks (nildew and leaf rust) and drought

stress throughout the maturity stage. Even the selected lines were

partially affecte t comparabla d e level d gavan s e yiel d tesan d t

weights intermediat s comparea e d wite controth h l parents.

Therefor resulte th e s obtained afte year3 r f fielso d

testing at normal sowing rate and conventional agronomic practices

would indicate thae induceth t d dwarfing gen s froe breedini e th m g

poin e spontaneouf vie o tth s goo a ws a d s Rhtl gene coming from Norm e takeb o . t nHowever 10 s intha ot i ,accoun t thae differencth t n i e plant height in favour of the rhtl/SD lines (about 15 cm) may compen-

sate for the Rhtl effect if the positive yield-plant height correla-

tion holds true.

The author is greatly indebted to Prof. S. ULLRICH for critical

reading of the manuscript.

References

) GAL(1 E M.D. effecte Th , f Noro s 0 dwarfin1 m g gene Yieldn o s . Proc h Inter5t . . Wheat Genetics Symp. Delhw Ne , i (1978) 978 - 987.

(2.) BAGNARA D., Results and Perspectives of Mutagenesis applied to durum wheat. CNEN RT/PROT. (1975) 11.

) GIORG(3 I B..BARBER , BITT F. , ACAVICCHION 0. I . YielG I d Perfor- F mancprogenie f o e s fro durua m m wheat cross involving two different semi-dwarfing genes: Rhtl and SD mutation. Proc. 2nd Research Coordination Meeting on "Evaluation of Semi-dwarf Cereal Mutants for Cross - breeding ". IAEA - TECDOC 307 (1984) 91-99.

(4) BOZZINI A., BAGNARA D., Creso, Mida e Tito, nuovi gram duri dalle eccellenti prestazioni. L'Informatore Agrario n. 35 (1974) 20347-20354.

75 GENETIC ANALYSIS, GENETIC IMPROVEMENT AND EVALUATIO INDUCEF NO D SEMI-DWARF MUTANT WHEATN SI *

C.F. KONZAK Departmen f Agronomo t Soilsd yan , Washington State University, Pullman, Washington, United States of America

Abstract

Recent results from breeding studies in T. aestivum wheats indicate that improved high yielding recombirants that carr e reduceth y d height gene Rhtl3 froe semi-dwarth m f mutant n combinatioi Magnil M 1 4 f n with Rht2 have been isolated. These improved lines should be useful in further breeding. In genetic analyses, additional data have confirmed thae th t reduced height gene Rhtlj from the mutant Karrag 522M7K is strongly dominant, while typical epistatic, partially additive interactions rray occur with othe t gene Rh d rrecombination an s 1; with differen r reduceo t Rh t d height allele n producca s e talle r shorteo r r derivatives. Thus e degreth , f dominanco e e or recessiveness of Rht genes appears to be a continuum, with their expressio n crossei n s further modifie y epistatib d c interactions with othe t allelesRh r . Mutant Burt M860 was found to carry a new rutant gene Rht20 tha s partialli t y dominan r reducefo t d heighte Th . reduced height gene rhtl f Bezostajo l a dwarf mutant Karlik-1 was largely recessive in the four combinations studied.

*Scientific Paper No. 7327. College of Agriculture Research Center, Washington State University, Pullman, WA 99164, U.S.A., Project Nos. 156 d 15708an , STEEP Paper 0326 and 0716. Part of this research was conducted while the senior author was or Professional Leave in Vienna, Austria in 1983, and part was conducted independently of Washington State University with private funds. The collaboration in part of this work by Dr. P. Ruckenbauer, Professor, Institut fur Pflanzenzuchtung, Universität Hohenheim, Stuttgart, BRP, is gratefully acknowledged.

77 . IturgiduT n m durum e partiallth , y dominant Rhtl4 gene Oste' f o l porzian o' showe d independent inheritance from Rhtl. The inheritance of two other partially dominant induced mutant genes, respectively Rhtl6 of Edmore SD1 and RhtlS, of 'Icaro1 (from E.N.E.A., Italy) differed from Phtd Rhtl4e an lTh . RhtlS locu f 'Duroxo s ' showed less dominance than Rhtl4d ,an o genethtw e s were independently inherited. Significant new useful genetic variation for breeding improved semi-dwarf bread and durum wheat cultivars has been induced. These mutants offer breeders greater freedon i m choosing Pht genes and combinations for cross-breeding to control straw height and lodging and to improve harvest index.

1. INTRODUCTION

Genetic sources for plant height reduction in cereal crops are now widely recognized as the most effective r:eans for reducing lodging susceptibility. Plant height reduction usually is a major contributor to lodging resistance and to higher harvest index, permitting the greater exploitation of genotypic yield potential under mere optimal production conditions. Moreover, some reduced height cultivars alse ar o well adapted to lower production, drought stress conditions. w genetiNe c source r planfo s t height reductio e needear n d in wheat, either to complement the widely used 'Daruma' (Rhtl and Rht2) gene and 'Akakomughi' (Akakomugi) sources (RJrtO and Rht9) or tc replace them whenever associated weaknesses, e.g., reduced coleoptile length, have yield limiting effectn o s stand establishmen n otheo r o rt properties [1]. Ther alss i e o the concer r genetifo n c vulnerabilit o possiblt e du y e associations of disease susceptibilty with the reduced height genes currently in extensive use. However, as of now, only Karl i k l (PI504549), of the new mutant semi-dwarfing sources in bread wheats, has been successfully exploited in improved reduced height cultivars. 'Odesskaya 75' and 'Odesskaya Polukarlikovaya' were develope e USS th d use Rn an di d[2] .

78 Several other height reduced mutant cultivars have been developed, but no other inducted mutant Rht gene is so widely distributed in cultivation or used in breeding hexaploid wheat s Rhtla s e durulth fron mI wheatsm . Kar1 k li , only Phtl e Darumth f o a n wid genei e (Rht us s eD i s? locate i e 2 th n i d genome). Consequently, nost of the semi-dwarf durum wheat cultivar n productioi s n today carry Rht1. Howeverx si , derived cultivars, 'Tito' and 'Augusto' (Italy), 'Miradur', 'Attila', 'Grandur d Signaduan ' r (Austriö) carr e induceth y d mutant gene RJvtj^ from 'Castelporziano' [3-12~i. This report describes progres n on-goini s g research with reduced height mutants of cultivated hexaploid and tetraploid wheats.

2. MATERIALS AND METHODS

1 Geneti2. d breedinan c g stocks

T. aestivuri' wheat - Many studies still in progress involv e hard winteth ere d r wheat mutant Karcag 522M7K,

described earlier [12, 14]. Karcag 522K7K is GA3 sensitive, about 60% as tall as 'Karcag 522', and has normal lax spikes, but is later maturing. Its coleoptile length is about the e parentth sam s a e. e mutanPlantth f o ts have wide leaves, large diameter culms that ten e o basespreat dth t .a d Burt M860 (PI503551), a reduced height mutant of the hard white winter wheat 'Burt s normay 1 carrha ,x spike na la lt y bu sothe r mutant traits, sinc e planth es densel i t w ylo waxya d ,an frequency of defective (weak, semi-sterile) plants occurs in the progen f crosseso y . 'Marzotto' (CI15267 a ver s i )y short Italian cultivar which probably carries Rht8 and Rht9 like 'Mara' (PI244854) [14]. Other 'tester' genotypes wile b l described where used. . turgiduT . duruL m m wheat - Rhts l sources usen i d crosses include Lloyd 'S1 = Cando/Edmore Sel. from North Dakotao localltw d an ,y developed lines UA6518 (PI499364d )an WA6754 (PI499366) e mutanTh . t sourcee studieth n i s s included 'Castelporziano1 (PIPI347731) which carrie n incompletela s y

79 dominant single qene Rhtl4 [15, 16]. Unlik e Rhtth el stocks, Castelporziano is GA., sensitive, shorter in height than Lloyd 'S' and has compact (club-like), awned spikes. Edrrore SD1 (PI499362) is a reduced height mutant induced recently in the tall, high quality cultivar Edmore (CI17748)A G s i t I . sensitive d appearan , o carrt s y some secondary qeretic changes. Durox (PK78306 a reduce s )i d height mutant carrying RhtlS, induced by EMS in the Washington State University research program. It is about 10-12 cm taller than the Rhtl genotypes. Duro s registerewa x n Franci d e (1980 s 'Carg)a i Durox y Gavadoub ' r Cargil d latean l r (1984) release s Duroa d x in Idaho, U.S.A [10]. 'Icaro1 (PI503555), an RhtlS mutant from 'Anhinga' was released in 1986 in Italy (Rossi, E.N.E.A., personal communication, 1985). Studies at E.N.E.A. showed that RhtlS differs genetically from Rhtl. The newer Phtl9 mutant Vie SD1 (PI503553) has been subjected only to preliminary investigations. The only other reduced height durum mutant cultivar known to date, GO 367, released in t availablno s r thesGreecwa fo e] e[9 estudies .

2.2 Breeding studies

Magnil (CI17689M 1 4 f ) derivative - Reselections s were made mainly froo crossetw m s with thi se Rhtmutanth 2d an t carriers 'Wared1 (CI15926) or 'Borah1 (CI17267) [11]. Several cf these selections were evaluated in yield trials from 1983-85. Derivative a singl f o s e backcros e o Magnit sar 1 4 f

r nenerationF e ith n . Generation advances were made with *J spring and winter crosses involving Karcag 522M7K, and selections with improved phenotyp e undear e r increase.

2.3 Gene interaction studies

Additivity, dominance d epistastian , c interactions among reduced height genes in both bread and durum wheats have been d lateinvestigatean ~ rF generatioe th n i d n progenf o y selected crosses, especially with source f Rhtlo s , Rhtd an 2 the Rht mutants previously mentioned. Culm height segregation results from several crosses will be described.

80 2.4 Height measurements, coleoptile length measurements, GAo responses

Plant heights generally were recorde e lengtth f s o a hd the longest culm of each plant. Coleoptile length measurements were made after growing seedling e darr seveth fo kn i ns

days 3 [16]responsGA r .Fo e information e seedlingth , s used for coleoptile measurements were grown in 1/4 Hoagland nutrient solution plus 10 ppm GA, (commercial), then continued additions. an e ligh ith r n fo t ! seven day r unti o se firsth l t leaf sheath was fully extended and the second leaf was visible [17].

3. RESULTS AND DISCUSSION

1 Geneti3. c analyses

T. aestivum wheats - Crosses to estimate the epistatic interactions, dominance and independence of several Rht gene

sources were made and studied through F?. Because of their e segregationnumberth f o ,w onlfe sa y obtainee ar d illustrated (Figs. 1-12). Preliminary conclusions regarding the Rht traits and their designations are presented in Table mosn I I.t instances, reciprocal crosses were analyzed, with essentially similar results, indicating that all genetic variation was due to nuclear factors. Parental height data were lost due to a field sampling error. Based on the F p data from several crosses, Burt M860 appear o carrt s a singly e incompletely recessive gene Rht20, differing from others against which it was tested, including rht4. A few defective, weak progeny, appeared as segregates in the crosses indicating that Burt M860 carries some secondary genetic alteration(s). Karlik 1 carries a recessive semi-dwarfing gene, designated rhtll, tha s independeni t f o t Rhtl, Rht2 and rht6. Burt background materials also evidently carry a 'grass clump1 dwarfing factor (D,, D,,, or D~) complementar o that y t presen n Karlii t 1 (datk t shown)no a .

Text continued on p. 87.

81 1 50 BURT M860/BURT .BURT M860/BURT M937(rht4) n-242 n-285 40

30 CO 20 a £ 10 a 5 o Lu 0 50- KARCAG 522M7K/BURT M860 KARCAG 522M7K/HOBBIT a: LU n-194 n-292 H 40 ID -z. 30

20 10 0 0 9 0 8 0 7 0 6 0 5 0 4 0 3 0 9 0 8 0 7 0 6 0 5 0 4 0 3 CULM HEIGHT (cm)

Fig. 1. F£ culm height distribution for the cross Burt M860/Burt, indicating partially dominant inheritanc e mutanth f o te gene Rht20.

Fig. 2. F2 culm height distribution for the cross Burt M860/Burt M937 (rht4), indicating independence, additivit d combinatioan y f o n e partiallon y dominane recessivon d an t e reduced height gene. Fig. 3. F2 culm height distribution for the cross Karcag 522M7K/Burt M860, indicating dominance of the Rhtl2 gene, probable independenc f Rlrtl2o e d _Rht20_an _ .

Fig. 4. F2 culm height distribution for the cross Karcag 522M7K/Hobbit (Rht2+), indicating probable independence and near additivity of semi dwarfing genes Rhtl2 and Rht2.

82 50 KARCAG 522M7K/BURT u KARCAG 522M7K/KARLI1 K n-259 n-418 40

30 CO 3 20 a 0 1 > ^—^ a ^ 0 7 8 50 - KARCAG 522M7K/OLYMPIQUE \- KARCAG 522M7K/BGRC 1215 a: LU n-204 n-307 40 30 20 10 0 30 60 90 120 150 30 60 90 120 150 CULM HEIGHT (cm)

2 culF Figm . heigh5 . t distributio e crosth sr fo Karcan g 522M7K/Burt, showing possible additivity of rht6 and Rhtl2 genes, plus epistatic interaction among gene n parentsi s . Fig. 6. ?2 cu^m height distribution fot the cross Karcag 522M7K/Karlik 1, indicating a wide difference between the two stocks, additivity of semi-dwarfing genes, but details are somewhat blurred. Fig. 7. F2 culm height distribution for the cross Karcag 522M7K/ Olympique, indicating partial epistasis of gene Rhtl2 as a basis e intermediatth r fo e heigh ^ (noF t t shown here). 2 culF Figm . heigh8 . t distributio e crosth sr fo Karcan g 522M7K/ BGRC001215, indicating a much stronger epistatic interaction between the tall ness factor of BGRC1215 with the gene Rhtl2 (and its recessive allele in Karcag 522) and the independence f alleleo s affecting height.

83 10 60 KARLIK 1/BURT LKARLIK I/COULEE n-345 n-269 50 40

3 30 a 20 i—i £ 10 § o 12 ÜL. a 60- MARZOTTO/KARCAG 522M7K I- Rht3 BURT/KARCAG 522M7K a: n-220 n-216 UJ trn CD JU i 40

20 10 0 J__L 0 6 0 4 0 4 2 00 2 0 10 0 8 0 10 0 8 0 6 CULM HEIGHT (cm)

Fig. 9. ?2 culm height distributio e crossth r fo Karlin k 1/Burt (rht6) indicating possible segregation of rht6 and Karlik 1 rhtll recombinants. . Fig10 . F2 culm height distribution for the cross Karlik I/Coulee, indicating independence and recessive inheritance of rhtll in Karlik 1 trait from Rht2 of Coulee (a Burt Rht2 derivative) ; in the effec e evidentb r rhto y t ma 6 .

. 11 Fig. F2 culm height distribution for the cross Marzotto/Karcag 522M7K, indicating additivit d independence an t geneyth Rh n i se th f o e parents e threth t e bu ,gene s segregating (Rht8, Rhtd Rhtl2an 9 ) make analysis difficult. . 12 Fig. F2 culm height distribution for the cross Rht3 Burt/Karcag 522M7K e majo Th t gene. Rh r s interac a partiall n i t y additive fashion.

84 TABLE I. EVALUATION OF CROSS COMBINATIONS FOR NUMBER OF RHT GENES, DOMINANCE, AND EPSITATIC ADDITIVITY

Epi stasis Cross Pht genes Additivity; Other Dominance Relations

1. Karcag 522M7K/Karli k 1 Rht12/rht11 Reduced 6 Fig. additivity; E , ND/R

2. Burt M860/Burt Rht20/0* PD/- -t-

3. Burt M860/Coulee Rht20/Rht2 Reduced additivity, E; PD/PD

t. Burt M860/Cim38 Rht20/Rht1 Slight reduction in additivity, E; PD/PD

5. Burt M86C/Burt M937 Rht20/rhft Reduced adaitivity, E; PD/R

6. Karlik rhtWRhtl rht6 Reduced Seg. Dw additivity, E; R/PD.R

. 7 Karlik 1/Coulee rht11/Rht2 rht6 Reduced Seg. Dw additivity, E; Fig. 10 R/PD,R

8. Karlik 1/Burt Rhtl1/rht6 Limited Seg. Dw additivity ; E , 9 Fig. R/R

9. Karcag 522M7K/Cim38 Rht12/Rhtl rht6 Reduced Seg. Dw additi vit; E >, D/PD,R

. Karca10 g 522M7K/Coulee Rht12/Pht2 rht6 Reduced Seg. Dw additivity, E; D/PD,R

11. Karcag 522M7K/Burt M937 Rht12/rhff rht6 Reduced Segw D . additivity; E , D/R.R

12. Karcag 522M7K/Burt M860 Rht12/Rht20 rht6 S1 . Reduced Fig. 3 additivity; E , D/PO.R

85 TABLE. I. (continued)

Epistasi s r ross Rht genes Additivity; Other Dominance Relations

'3. Karcaq 522M7K/Marzctto Rht12/rht8 rht9 Di stinct Fig1 1 . reduction i r. additivity; £ , D/PD

Karcag 522M7K/Ci17329 Rht12/rht1 Reduced additivity; F , D/PD,R

15. Karcag 522M7K/CI17324 Rht12/rht2 Reouced adaitivity, F; D/FD.R

16. Karcaa 5Z2M7K/Rht.) Burt Rht12/Rht3 Reducen Fig2 1 . additivity; E , D/PD,R

Karcag 522M7K/Burt Rht12/rht6 [imited Fig. 5 edditivity strong domi nance; D/ R

. Karca18 g 522M7K/BCRC1215 Rhl12/rht Partial Fig. 8 epi stasi s; MD

. 9 1 Karcag 522M7K/01yrrpique Rht12/0 Partial Fig. 7 epi statsi s NÜ

. Karca20 g 522M7K/Kobbit Rht12/Rht2 Reduced Fig. additivity, E; D/PD D = Dominant, ND = near dominant, PD= partial dominant, R = recessive, Burt and Burt derivatives carry rht n commoni 6 . E = Epistatic effects Dw = Crass Clump Dwarfs

86 Reduced height gene rht6, present in Burt and related materials s difficulwa , o detect t n somi t e crosses becausf o e its small effect. However, rht s readili 6 y detectabln i e Burt/tdller wheat crosses. Previous results had indicated that the mutant gene Rhtl? of Karcag 522M7K was unique among height reducing factors ir wheat [11 j. New evidence presented here (Figs. 3-8, 11, II) demonstrates that gene Rhtl2 expresses its own range of epistatic and additive genetic relations with other hfiqht oene sources n crossesI . , gene Rhtl2 shows partial additivity also with other reduced height factors, including Rht3. Sutka (personal communication, 1986 s recentl)ha y located Rhtlo t 2 chromosome 5A, revealing that a third chromosome qroup carries a major gene causing plant height reduction. The tall cultivar 'Olympique1 (BGRC20156) a soft red winter wheat froe Germath m n Collectio t Braunschweia n g carries no reduced height genes. However, the cross with BGRC1215 indicated that Karcag 522M7 y carrma K a secony d

reduced height gen a commo ee b whic ny differencma h e between e originath l Karca ? e verari52 th gd y ta!1 RGPC1215 (see Fig. 8). In T. turgidurn durum, we analyzed the F~ of several crosses involvin w semi-dwarne g f mutants r resultOu . s support those of Georgi [17] that the Rhtl4 gene of Castelporziano is inherited independently from Rhtl, and transgressive

recombinants have been recovered (Fig. ? F 13) e .Th segregation from crosses between Rhtl carriers WA6518 and WA6754/Edmor 1 indicateSD e e probablth s e independenc f thein e r Rht genes (Fig. 14 a,b). Fp data from the backcross to Edmore indicate that the Rhtl6 gene of Edmore SD1 is partially dominant (Fig. 15). Laboratory data showed that s Edmori 1 SD e GA, sensitive like Edmore, and it has a long coleoptile. Edmore SD1 maintains its semi-dwarf height under the rainfed conditions tested, but responds more in height under irrigated conditions than Rhtl carriers n thaI .t respect s responsit , e to environment is much like that of the Phtl4 gene carrier Grandur. Edmore SD1 was induced in a high-quality cultivar, and thus should prove usefu n furthei l r breeding. Backcrosses have been madf extraneouo o fre t et i e s genetic changes.

87 13

CASTELPORZIANO/ LLOYD S 30 2 21 N=

LO _J

Q 20

ac. 10 LU en

W 50 60 70 80 CULM HEIGHT (cm)

. Fig13 . F£ culm height distributio e crosth sr fo n Castelporziano/Lloyd 'S1, indicating independent inheritance of the partially dominant Castelporziano gene Rhtl4 from gene Rhtl of Lloyd 'S'. Both additive and epistatic effects occur.

14 WA 6754 / EDMOÜE SC 30 20 10 0 i/i WA 651 8/ EH10RD S E ^ SO a RHTI ~ 707 37 - N § CO

a œ tO LU H 30 ^ 20 10 0 40 50 GO 70 80 CULM HEIGHT (cm)

Fig. 14. F£ culm height distribution for the crosses WA6518 and WA6754/Edmore SD1, indicating possible independence of new mutant gene Rnt16 from Rhtl as well as epistatic interaction and partial additivity of the Rht genes.

88 15 EDMORE/EDMORE SD PARENTS 20 P! N = 73

P2 N = 95

_ 10 ZoD

o EDMORE/EDMORE SD E 20 CD f~ 2 N = 136 6 SHORT,STERIL+1 E PLANTS

50 60 70 30 90 100 110 CULM HEIGHT ( CM )

. Fig15 . F£ culm height distributio e crosth sr fo Edmore/Edmorn e SD1, indicating partial dominant behavior of gene Rhtl6 of the mutant. Different parent heights are related to field locatio d planan n t density.

Crosse e mutanf EcVorth o s 1 tSD e gene Rht.15 carrier with Durox or Grandur (Rhtl4), and with the newly acquired RhtlS mutant, Icaro, showed codominanc d apparentlan e y independent segregation. The cross Grandur/Durox segregated a rati9 (61 f o o) medium tall:4 (34) medium short:3 (17) short . progenyF , demonstratin e partiath g l dominanc e Phtlth f 4o e e partiath gene d an l, recessivenes e Rhtlth f S o sgen d an e their epistatic interactions. Transgressive recombinants also were recovered from the cross Icaro/Durox indicating that RhtlS and RhtlS are independent. In fact, a list of the 20 reduced height genes and sources shows that most Rht genes show partial dominance and few are completely recessive (Table II).

89 öl C r^. >r- y -D •o CD l 3t "X> C C C c - -r ) Q J O ^ ^ 00> - r - '. - r •r~ — i D D4-)-Pt D ( D f 3 ) *O lJ O c 4-) l/l l/) JJi/14Jt_4-)TJ4-JUl-l- t - E E > 0 O 4> XJT33O3ODO"OOE(J ^ E 0 0 tn •r--^ocoi-oooco. L - l c O C ^3corDQO.c;5:2:r5Loz. Q - O i O L Z3

j- Q o.u_t/)urtnctrQiii;cc:Loa:oo Q- m O. CO

ro D i/l

D 0 4-> O. •rfO- 4V>) — — — (/)(/)(/) tO v/> (/) o c — o c (/)(/ O C > o c u ce o t/l CO t/i «a: < O

^ i — ^n m ,— EE ^ er 01 4 ^ r — . l - 4 . L •r- (DfD 4/>l>OOC.c/l*0 •^ 4> o u U C u r V - y > i/ j U — 4 J J 4-> 0) C " "O c o. o o ••- 4J IDfO (-L-t-L-nDTOCJlNi^ Ol Q. CO E C IÎ3 v _Ü 3 r^ CD (D y v •(— (jj *u t) T3 *40 T3 — z: < ^ uj

h—

Lu CN X C Öl oOcocoZ^HcoZtcococoZI. z : 2 : 2 E : i Z — 0 ._ , ,_ .O CN ro ÜJ in ro Z ÜJ . ^*— - S ro ^ cr o — ^ — . ) Ces D ~ o or o c > o° L/"» o c 0 3 m CD — CD r~- co -a- o r -3- — - u f~- . o m o - -a n t o i CT ^ - ^- T— ^ - - -^ z o o r n i — co cn — O o 0 j- u_ — — ix> — — m o r ^ c — ce O U CD Q- — r-. . O 0 0 10 «^ — — CD ~— o. z: D f J 4 CNt \^ -— ' ^ ~ - j N ' E O xa r- t— t— D > ^- ONI 1 OOEroZ: — IL'O T-u-5 0i c. E — ^-- »— D o"t C-J ^o c o. ^- l Ö z: ^ l T 4) J D " Q "— * 1 2 r~ ) Q — i ^4— OJ U CCI— 0} U •>*•<-•>- 1) X L. oo s_ O O 1 4- C 1-I-El-L.l-l-l-l-E l . l_lL n t _1 0 O OOO^fD^lJfDfü "f~ fü fD t— co i=^^cu2;Qucä2:2:<^^Ü L Q o : : z O

ÜJ 1> X E 0 C Q i/l O ÜJ 0 — UÎ ; < - C Q Q C u < " C - c^ . c^ E r < 4-1 Q

ÜJ J CN — * O ro -^" in *°D U co 4-> C 4J 4-> 4-> 4J JZ 0) JZJZJZJZJZ^TJZJZJZJZJZJZ i— ce o cecectcecececececececece & & & &

90 TABL . (continuedII E )

Rht Chromosome Initia1 Associated 2 Gene Location Source Origin Material GA3 Response Dominanc en Breedini e Us g

7 1 t Rh 7 Chris Ml (C1 17241 ) M Chri s S Rec. Uncertain

Rh8 t1 7 Icaro (PI503555) M Ar.hinga S Semidom. Promi se

Rht 19 7 503553I (P Vil M e) M Vie S Semidom. Promi se

Rht20 7 Burt M860 (P I503551) M Burt S . dorP . Prome is

Adapted from Gale and Youssefian (1985), Konzak (1982), Konzak (unpublished), Konzak (1986), Mclntosh (1973), Heiner and EUayed (1974) and Pepe and Heiner (1975). 2 M = induced mutants, S = spontaneous, ? = unknown. = GibberelliI 3 insensitiveA n = gibberelli S , 3 sensitiveA n . l, P. dorn. = partial dominant, Semidom. = semidominant, Rec. = récessive, Str. dorn. = strong dominant. Partial dominant = partial récessive, Semidominant = greater dominance, Strong dominant = almost complete dominant. Durums. Doubtfu = unlesl s modifie y additionab d l genes; Som r severa= erecenfo e lus t cultivars; Promis = gooe d potential, Uncertai = promisen t stilbu , l under investigation--modification seems possible. Likely responsiv r "triplfo e e dwarf" effec breedingn i t s comparablha ; y smaller effect than Rht r Rht2o l . 8 Personal communication (Gao, Mingwei . ChinaR . P ,, 1985). * By inference also in Italian T. aestivum cv 'Forlani' and 'Acciac1, and durum derivatives 'Jucci', 'Montanari' and 'Ringo', based on geneology (Vallega, 1974). 2 Breedin3. g studies

. aestivuT m wheat - Mans y selections were made from crosses involvin e onlth yt possiblbu g , MagriMl 1 e4 f carriers of the mutant gene Rhtl3 which have been advanced to yield performance trials are lines which also carry Rht?. These line e K790GC85ar s , K7900100, HP830007 d HP830015,an l Al . four lines are very short in height (>60 cm) when grown under irrigate - insensitive dGA th conditionse o ar t l e al du e d an , dominanc f theio e r Rht2 Gai2 gene component. Their coleoptiles appear to be short like Rht2 carriers, but are not as short as those of Rhtl Rht2 semi-dwarfs. No direct descendents carrying only Phtl3 from CI1768Q havt proveye e d worth f yielo y d tests. However s hopei t di , that crosses involving these very short semi-dwarf lines will produce better progeny. Germplasm improvement studie e continuinar s g in an effort to develop Rhtl3 carriers with better agronomic properties.

. 4 ADDITIONAL COMMENT D CONCLUSIONAN S S

Detailed investigations to establish the chromosome location f mutano s t semi-dwarfing genes havt beeno en possible r moriou n e practically-oriented program. Thus r analyseou , s have been limite o "testert d " type crosse d backcrossesan s , the progeny of which may have value in variety development or ir aermplasm improvement. Many of these combinations involve segregatio * reduceo n d height loci other than those under investigation, often making segregations difficult to interpret. Eve, sucso nh combinations often provide reasonable estimâtes of relationships which can later be tested in combinations that allow for greater analytical precision. Until better (isogenic) tester line e producear s d for each mutant Rht locus, such crosses are a reasonable alternative since they also provide additional information on breeding value, whereas many tester or analytical crosses do not. The numerous crosses investigated suggest that the degrees of dominance vs. recessiveness of Rht or rht genes form a continuum of expressions which are further modified by

92 epistatic interactions between and anong Rht gene loci. Some of the newer Rht loci may yet prove to he different all el es of a single locu r pseudoalleleo s f closelo s y linked genes. Results, particularly with durum wheats, suggest thae th t mutation breeding methods have excellent potential botr fo h direct variety development and for producing new reduced height gene resources, since productive mutants are readily isolated. Even so, it appears that the breeding value of semi-dwarf mutant y exceema s d their potentia r direcfo l t use.

REFERENCES ] DALRYMPLE[1 , "DevelopmenD. , d spreaan t f semi-dwaro d f varieties of wheat and rice in the United States. An international perspective", U. S. Department of Agriculture, Offic f Internationao e l Cooperatiod an n Development/U . AgencS . r Internationafo y l Development, Agr. Economic Report 455, Washington, DC (1980) 30. ] LYFENKO[2 , S.F., ERINYAK, N.I., FEDCHENKO, V.P., SOZINOV, A.A., HEIFETS, A.M., Triticum aestivum, Odesskaj, 75 a Odesr.kaia Polukarlikovaja, Mutation Breed. Newsl4 1 . (1979) 11. ] SCARASCIA-MUGNOZZA[3 e line, Du G.T.i frumentd e, o duro ottenut r mutazionpe e e indotta, Nctiziario CNEN4 (1968) 3. [4] BOZZINI, A., BACNARA, D. , Creso, Mida e Tito: nuovi grani duri dalle eccelenti produzioni, Informatore Aqrario 20 (1974) 1. ] BÀGNARA[5 PORRECA, . D , , POSSIG. , , L.B., Durum wheat--Augusto, Mutation Breed. Newsl ) (1977K . . )14 ] HANSEL[6 Triticu, H. , m turgidum conv. durum, Probstdorfer Miradur, Mutation~Breed. Newsl. 13 (1979) 20. [7] HANSEL, H., Triticum turgidum ssp. ojmjm, Grandur, Mutation Breed. Newsl. 16 (1980) 18. [8] ADAM, J., Triticum turgidum ssp. durum, Attila, Mutation Breed. Newsl 6 (19801 . . )18 ] SKOPDA[9 , E.A., Triticum turgidu G 0367 - m . Mutation Breeding Newsl 8 (1981TÏF1 . : [10] KONZAK, C.F., Triticum turgidum ssp. durum, Cargidurox, Mutation Breed. Newsl (1983. 21 .. )17 [11] KONZAK, C.F., WILSON, M.R., FRANKS, P.A., "Progresn i s the evaluation, use in breeding and genetic analysis of semidwarf mutant f wheat"o s , Semi-Dwarf Cereal Mutants and Their Use in Cross-Breeding II (Proc. Res. Coord. Meet. Davis. 1982), IAEA/TECDOC-307, IAEA, Vienna (1984. )39 [12] KONZAK, C.F., "A review of semidwarfinq oene sources and a description of some new mutants useful for breeding short-stature wheats", Induced Mutationn i s Cross-Breeding (Proc. Adv. Group Vienna, 1975), IAEA, Vienna (1976) 79.

93 [13] VIGLASI , Short-straweP. , d mutant f Karcaqo s 2 winte52 y r wheat induced by gamma rays, Acta Agronomica (Hung.) YJ_ (1968) 205. [14] GALE, M. D. and YOUSSEFIAN. S., "Dwarfing genes in wheat", Progress in Plant Breeding 1 (RUSSELL, G.E., Ed), Butterwort Londo, . Co hn & (1985. )1 [15] MYHILL, R.R., KONZAK C ,w techniqu ne .F. A , r fo e culturing and measuring barley seedling:, Crop Science 7 3 (1967) 275. [16] KONZAK, C.F., FAVRET, F.A., "Seed rr.eristemass radiobiological ter,f systems", The Dynamics of Meristerr, Cell Populations (MILLER, M.W. KUEHNERT, C.C., Eds), Plenum Press w Yor,Ne k (1972) 227, [17] GEOPGI , "EvaluatioB. , f short-streo n w mutants in cross- breedin f barleo g d duruan y m wheat" Proc. Fourth FAO/IAEÀ Res. Coor. Meet.,ENEA-FARF, Casaccia, Rome (1985). These Proceedings.

94 BARLEY MUTANT RELATION SI N TO CULM LENGTH

U LUNDQVIST Svalof AB, Svalov, Sweden

Abstract

The seîi-dwarf type in barley is very heterogeneous, redaced culm length being mor r leso e s charactenstica a numbe f o lf o r different group f nutanto s e shor e n th barlesidi s th f t o e t »a y. all- mutants proper. Thus, short culm may occur associated with the mut- t characteran s erectoides (short spikes )praematuru, m (.early/, gl obosum (rounded seeds )uprigrit, d strawstian , . ff Covariation studies of 111 mutants in the five ert-loci ert-a, -b_, -c, -d, and -e_ showed a positive correlation between cal"! lengt d yield_nan h g ability e patternTh . f distributioo s n differ among the loci, but favourable deviants of semidwarf type are j.na^- l fiv al catee three r th loci fo der maiFo . n mat-loci a mat-aan , -b , -_co correlation , n between culm lengt d yieldinan h g aoil^ts wa y shown, mutant n mat-i s a generall d shorteha y r culm length Thus, mi tants of the praematuruir type compared witn mutants of the erect- Oj.dcs typ offemay e r more favouraLle material seêctinfor s - ~ i a yielding seTii-dwarf types. 2 shor5 Aôn e t th gcul m mutants, those w^th extreme reductô- of culm length showed, without exception, strong reduction of yield .3 strawstif 2 Amon e th g f mutants e otretn rn o , handc v t , majority, even amon e shortesth g t ones, exceede e averaath d c vield of the mother variety. In an N1 material of cv Sv Frida, sodium azide comparsd wt neutrons tarnea oat to oe clearl\ nore efficient to produce sv or*- cul M nlines . In studies of nutations affecting the development of lateiai florete threth n ei s two-ro v BurusS Kr^st^n ' v c wJ Sv Foma E , d an ,a single nutant f intermediuo s m type showe o effecn d m ItT^*r io t.ai ^ d maintainean e varietath d l differences. Doabl t mutantsin e , irrespective of their beinq derived fron cross combinatj-O1-s v/itf ^ a variet r betweco y r varieties showe a narked d reductio f cô n 1- lengtr. Triple mutants, wite additionath h l contributioa f o n s^x-row gene fron locus hex-v, showe r apparena d t increas n culri e r length. A special interaction between the six-row locus or one sid d int-loc °an e othe th rn o isid mads i e e probable.

INTRODUCTION The Scandinavian mutation work in crop improvement has been carrie n sinco d e abou years0 5 t , wite plant-breedinth h g institute at s centreSvalöit d wits a van , h s foremosbarleit s a y t research material. Bein diploia g d self-pollinatingan d , barle s easi yo t y handle in repeated experiments and has become a model crop all over the world where barley is cultivated. At Svalov, a broad spectru f easilo m y recognized mutation type barlen i s s beeha yn

95 screened for, and a collection of more than 9,000 isolated mutants is now available. Several of the mutant groups have been studied genetically and biochemically in deep detail and with regard to plant-breeding value and matagen specificity. Since 19 , trie collection of mutants is in the process of being stored c Nordi^.ti i c gene bank, Tie se^.i-dwarf type is of interest for plant breeding in barley. Genetically this type is very heterogeneous, reduced culm length be^ng more or less characteristic of a namter of different groups of mutants in barley at the side of the short culm mutants proper. Thus, short cali^ occuna r r associated wite th h mutant characters erectoides (short spikes) , praematurum (early) , globcsuT. (rounded seeds )upright, d strawan , s tiff. For the present " semi-dwarf project" some of the mutant groups have attracte r particulaoa d r interest, namely erectoides mutants i with about 1,200 cases) , praernataruir. mutants (with abou C cases90 t )globos^, m mutants »with abou 0 cases20 t )"up, - rignt" mutants (with about 150 cases) , " strawstif f " mutants (wj.th abou 5 cases)2 t d matantan , s with "short calm" (with about 0 cases5 )Concernin. g their yielding abilit e globosuth y d an m upr_gnt groups have been fairly disappointin n earliei g s wela r l e presenth n ai s t yield trials; the e yincludeb wilt no ln i d th^t report.

COMPARISO E EkLCTOIDETH F O N S (ert D PRAEMATURUAN ) M (mat) MUTANT GROUPS The matants discussed in the following are mainly derived fro~ the Svalcf varieties cv Sv Bonus, Sv Foma , and Sv Knstxna. Tr e matagens used are radiations (sparsely and densely ionizing )oigani, c cnemicals d sodiuian , j azide. n fcc.rlj.trI r inves Arri*cn> t bj « ste, ig Hagcer d Goraan g n Pers- scr , 2t_ trtctoides (ert; loci hav'e been identified, with alto- get 5 ulocalizee20 r d matations (It. Mor f theseo - tha" ma e 50 n are localized to the four loci ert-a , -, -_d_ , and -m. L-'cas ert-a riovve\tris, i asbociatenot , d wj_t:i redactio calof n m lengtn and is, therefore, of no interest in the present context. There is a pronounced tendency to mutager. -specif ic reaction e ert-locth Es'iec^all. f ) o o loc(1 itw ^t ert-th y d ert-an a c behave differently: anong 33 ert-a mutations only 1 has been in- da^e y denselb d y ionizing radiations n contrasx , o about % 50 t stationm e ert-6 3 tn cn e i sth locus f o . Earlier investigations have also shown the erectoides mutants induced by irradiation to be generally superior in yielding ability to mutants induced by chemical mutagens (2) . These investigations have also shown thae differenth t t ert-loci affect yielding ability differently (2) e geni.Th e backgroune th f o d varieties from which the mutants are derived also has turned out f importanco e e practicab th o t r fo e l e matantvaluth f o es (2). Concerning the praematurum (mat) mutants, 9 mat loci, with altogether 85 localized mutations, have been identified. More f theso tha 0 e8 n mutation e localize ar se threth o et d loci mat, -a -L, and -£. Only these tnree loci have been included in the seir.i- dwarf studies s lonha gt I .bee n known that mutants *;ith extreme burliness have a shorter calm, usually lacking one of the internode £ . Covariation diagrams for calm length and yielding ability oase n two-roo d w plots froe yeaon m r (1982 e availablear ) . Alto- gethe mutant1 11 r n fivi s) e - ert-loc d an , -d i , (ert-a-c , -b ,

96 showe positiva d e correlation between culm lengt d yieldinan h g ability. The patterns of distribution differ among tne loci; but favourable deviants of semi-dwarf type are indicated for all five

loci. in total, 16 of these mutants are indicated to be of potential practical valua serra-dwar n i e f project. Abou 0 mut20 t - ants not localized but suspected, on morphological grounds, to belong to the ert-a or the ert-c locus again showed positive correlation between culm lengt d yieldinan h g ability w witno ht ,bu only 6 favourable deviants recognized. Covariation diagrame threth r e fo smai n mat-loci (mat-a, -b_, d -_can ) with altogethe 8 mutant6 r s showed, surprisingly o corn , - relation between culm lengt d yieldinan h g ability s coni t -I . cluded that mutants of the praematurum type compared with mutants e erectoideoth f s typy offema e r more favourable materialr fo s the selection of high-yielding se^.i-dwarf types. The diagrams indicate differences amon e mat-locith g , matant n mat-i s a generally having a shorter culm length. It is interesting in this connection that our recent observations indicate that sodium azidc, compared with other mutàgens s lesi , s efficien n produci t - ing mutation n locui s s mat-a .e absenc th n adequatEvea n i f no e e star.dard for the praerr.aturum plots, several of these mutants are indicated to Le of practical value in a semi-dwarf project.

"tHORT CULM" AND "STRAWJTIFF" MUTANTS Previous data had not been particularly favourable, but the data D<_ing meagr a more e extensive stud f tneso ^ e matants swa done in the sumrier 1934. A e numbeshorth v Bonusf S mutantf to ro v cul2 c 5 , f mo s e strawstifth f o 3 2 type fd t_vpan , e were studie a fiel n i dd trial, wite motheth n r variet a standard s a y e tendenc.Tn - re o t y daced culm length showed a strong variation among the short cul"- mutants, and the mutants with extreme reduction of culm length showed, without exception, strong reduction of yield. Mild reductio f culo n m length wasa rule s a ,, associated with mild reductio f yield o na smal d lan ; number among these mutants were equal r teveo n exceeded their mother variety. Thero n e e seenb o :t bright prospects of finding short culm mutants combining some reduction of culm length with improved yielding ability; but the possibility certainly exists. The strgwstiff mutants, on the other hand, showed an interesting picture n averageO . , they showe mildea d r reductiof o n culm length. Of greater interest is tne fact that they showed a much weaker association oet^een yield and culm length. Remark- ably e majoritth , y amon e strawstiftn g f mutants, even amone th g snortest ones, exceeded the averaae yield of the mother variety. It will certainly be an important tabk to look for a venfj.cation of these tenden^es in furfier trials, because neither of the tw'o matant groups have given particularly encouraging resalts in earlier trials.

MUTAGSN SPECIFIC REACTION R SHORFO S T CULM PLANTS In 1934, in connection with the harvest of plants that had been tagged as "early" in an Mn material of cv Sv Frida, a nurier of short culm plants were also selected 5 amon19 , g them after treatment with sodium 6 afteazide6 d ran , treatment with neutrons. These plants were distinctly more short-culm thae earlth n y plants selecte e samth e n plotsi d e frequencyTh . f short-culo m

97 M plants was clearly higher after sodium azide treatment. Inter- estingly enough, sodium azide also turned out to be clearly more efficient to produce short-culm M_ lines (67% among the lines, against 35% among the lines after neutron treatment). In this material, culm length and spike length were, as expected, positively correlated in the M_ lines, but deviants with shorter culm and longer spikes appeared after both mutagenic treatments t aboua ,% frequency 10 t . Unfortunately, yield datr fo a the M lines (grown in 1985) are not yet available. Nevertheless, there~are suggestive indications that culm shortening without reductio e achieveb n yieli ny ma dy mutatiob d n breeding.

CULM LENGTH IN RELATION TO MUTATIONS AFFECTING SPIKELET DEVELOP- MENT Sone dat e presenteab wilw no l o shet d w that mutation- af s fecting spikelet development in barley may also interact to affect culm length n normaI . l two-ro wo row barletw f mai o se nth y floret e eacar s h surrounde o row tw f small o sy b d , sterila an e awnless lateral florets n six-roI . w barley these lateral florets are well developed, fully fertil d carryinan e g well developed awns. The two-row barley can mutate in a single step to six-rcw barley; these mutations have so far been localized to one and e samth e locus, named hex-v. Besides, two-row barle n givca ye ris o mutantt e s with enlarged lateral florets, wher n developaw e - ment, fertility d kernean , l development var n characteristii y c ways. These mutants hav a spike e development tha s intermedi t - iate between two-row barley prope d six-roan r w barley proper, and the mutations are therefore named intermedium mutations. A considerably greater numbe int-loc1 1 f genr o r fa e io locs - i have been detected - are able to influence the development of lateral floret n thii s s way. These genes generally act recessively. Two of the loci - hex- d e int-semidominantan ar v - d . Increased developmenf o t lateral florets that is due to co-operation between such loci has been observed ' -, 4). 7':ijf, different i:;t-lo>. i c om: .ir.c-d IT double homozygotes frequently give ris o typicat e l six-row type; and the combinations between such double rr.uto.rits and the six-row gen n tripli e e mutants hav e ablb ec produc o t eturnet - t ex ou ed tremely beauLiful six-rcw types. The ensuing discussion will centre upon change n calrri s , length that have been e founb o t d associated with these kind f mutationo s n differeni s t corrJjina- tions. e int-mutantTh s involve n thii d s stud e derivear y d from three mother varieties, cv £v Bonus, Sv Foma, and Sv Kristina. Mutants, e mainlfouth rn i yint-locd -_ean , , totalld - i , -^a-c y, 53, plus the six-row gene hex 3 arid the six-row variety cv Sv Agneta fore basith m c materia r dour>lfo l e mutant combinations between intermediu mr triplgenesfo d ean , mutant combinations between intermedium gene d six-roan s w gene. Result e availar s - able from three condition f cultivationo s n 192i , d 19B5e 4an Th . year 1985 was characterised by drO'Ujhts, which aff>*ctpj plant development harmfully. Consequently, culm length e generallar s y highe n 1984i r . e motheTh r varieties differe n averagi d e culm length. Single mutants of intermedium type show no effect on culm length d maintaian , e varietath n l differences. Double mutants, irrespective of their being derived from cross combinations within a variety or between varieties, show a marked re-

98 TABL Varieta. EI l difference culn si m lengt intermediur hfo (mean) cm n si m genes in barley. Number of cases behind the means, in parentheses.

Mother variety Year Material studied Bonus Foma Kristina Remarks 1985a Single nutants 54,5 56.7 48.7 (10) (23) (18) Double mutants 48.7 49.7 47.8 (24) (106) (78) King-size, hex 3 53.3 56.2 53.9 (7) (51) (34) King-size, Agneta 54.4 54.6 53.4 (23) (82) (55) Mother varieties 54.4 56.4 54. 59.= 3 60x he Agneta = 50.9

1985b Double nutants 57.1 58.9 56.9 (28) (111) (81) King-size, hex 3 57.9 63.2 61.1 (15) (50) (39) King-size, Agneta 61.8 64.4 62.0 (23) (90) (59) Mother varieties 64.1 64.5 60.5

1984 Double mutants 75.6 79.3 77.0 (28) (106) (72) King-size 3 x 80.he , 1 83.6 83.8 (13) (58) (45) King-size, Agneta 86.1 86.8 87.2 (26) (93) (51)

TABLE II. Influence of varietal combinations on culm length (means in cm) for intermedium genes in barley. Number of cases behind the means, in parentheses.

Combinations of mother varieties Year Material studied F+F K + K B + F B + K F + K 1985a Double mutants 50.0 48.6 53.1 44.3 48.4 (25) (11) (12) (12) (44) King-size 3 x 57.,he 2 54.5 56.9 48.6 54.3 ) (3 (17 ) (4 ) ) (7 (15) King-size, Agneta 55.0 53.4 55.9 53.0 53.6 (21) (7) (11) (12) (29)

1985b Double mutants 59.1 54.8 59.5 55.3 58.8 (28) (11) (12) (16) (43) King-size 3 x 64.he , 5 60.1 57.9 58.0 63.3 (13) (7) (7) (8) (17) King-size, Agneta 64.5 59.8 64.5 59.7 64.1 ) (8 (10(25) ) (13) (30)

1984 Double mutants 80.5 77.7 78.0 73.8 78.0 ) (8 (12(27) ) (16) (40) King-size 3 x 85.he , 0 88.8 82.9 77.8 82.0 ) (7 (22 ) (6 ) ) (8 (15) King-size, Agneta 86.9 91.4 87.0 85.3 86.6 (26) (5) (13) (13) (28)

99 auction of calm length. Triple nutants, with tne additional contributio e six-roth f o n w genr froo e extremee3 th m frox he m - ly short-culm six-row variety Agneta, show an apparent increase in culm length (and in sp.ke length as well); accordingly, we have named them "King-size". Interestingly, King-s^ze types involving Agneta are generally fie strongest ones. To s-rriracr_ze . Varietal difference n cali s m lengtn (TABL ) e I areE th . ,or whole, maintained amon e singlth g e Datants. Doue-le mutante ar s clearly lower than single notants. King-s-ze plant e clearlar s y higher than double mutants unde l conditional r f cultivationo s . No hetercsis effect can be demonstrated ^hen int-ger.es fror, different varieties are coTiined (TABLE II1. Nor can a heterosis effect be seen at the level of King-size types (hex 3 being derived from cv Sv Bonus). An effect of interaction between int- e side d six-roger.eon an n , o s w e ethegenetn n ro s side s i mad, e probable. Different culm lengths are associated with the four more closely investigated int-loci -a, -c, -d_, and -£ (the remaining 7 loci being excluded because of too few representatives (TABLE III). Interestingly, these differences for single mutants are maintained at the level of double mutants, even at different conditions of cultivation. King-size plants behave in a more irregular way.

T3VELE III. Influence of gene loci on culm length (means in cm) for intermedium gene barleyn i s . Nunbe f caseo r s behin e meansdth n i , parentheses.

Intermedium loci Year Material studiea d

1985a Single nutants 52.5 52.1 53.1 62.7 (20) ) (4 (15 ) )(9 Double nutants 48.0 48.3 49.4 55.8 (54) (73) (63) (10) King-size, hex 3 55.7 54.7 55.1 53.6 —— (24) (34) (28) (5) King-size, Agneta 54.0 53.1 55.0 59.5 (44) (55) (46) (8 )

1985b Double nutants 56.4 56.9 59.2 64.3 (60) (77) (66) (9 ) King-size 3 x 61.he , 5 61.9 61.6 61.0 —— (28) (37) (30) (6) King-size, Agneta 62.7 61.4 65.1 63.7 (48) (58) (51) (7)

1984 Double mutants 76.6 76.8 79.0 87.4 (58) (71) (60) (10) King-size 3 x 81.he , 6 82.2 85.7 86.0 — — (30) (45) (32) (7 ) King-size, Agneta 85.5 84.9 89.2 91.0 (51) (57) (47) (8 )

100 particulao Thern s i e r effec f interactioo t e seeb no t n when different int-loci are combined in the double mutants (TABLE IV). The variation seems to be due mainly to tne differences between individual int-loci (longer cul n averagmo e char- acterizing int-d and -e). Tnis sjpports tne conclusion that the KinT-size effect depends mainl a specia n o y l interaction Detween the six-row locus on one side and int-loci on the other Sj.de.

TABL . InfluencIV E f geno e e loci combination culn o s m lengtr hfo ) (meancm n i s intermedium gene barleyn i s . Numbe f caseo r s behin e meansdth parenthesesn i , .

Combination f intermediuso m loci

Year Material studied a + c a + d c + d c + e d+e

1985a Double mutants 47.8 48.3 48.7 55.2 56.7 (32) (22) (32) (6) (4) King-size 3 x 54.he , 6 57.3 54.6 57.1 48.3 (14) (10) )(2 (16 ) )(3 King-size, Agneta 52.3 56.5 53.2 59.5 59.5 (26) (18) (2 (21 ) )(6

1985b Double mutants 55.3 58.1 57.8 61.7 67.6 (36) (24) (33) (5) (4) King-size 3 x 62.he , 2 60.6 62.3 59.1 62.9 (17) (11) (15) (3) (3) King-size, Agneta 59.6 66.7 62.7 62.6 66.4 (27) (21) )(2 (23 ) )(5

1984 Double mutants 76.2 77.4 77.2 83.9 89.8 (37) (21) )(6 (28 ) )(4 King-size 3 x 79.he , 7 86.1 84.8 82.4 90.7 ) (9 ) (3 (19(21) ) )(4 King-size, Agneta 83.3 89.1 87.0 85.3 96.7 (32) (19) (19) (4) (4)

Acknowledgements.- I thank Arne Lundqvist for valuable discussions. This stud s supporte wa ye Eri th k y b dPhilip-Surense n e FoundatioSwedisth y b h d Councian n r Forestrfo l d Agriculan y - tural Research.

REFERENCES

(1) PERSSON , HAGBERG,G. , Induce,A. d variatio a quantita n i n - tive characte barleyn i r . Morphclog d cytogenetican y f o s erectoides mutants, Hereditas 61 1-2 (1963) 115. (2) GUSTAFSSON, A., Productive mutations induced in barley by ionizing radiation d chemicaan s l mutagens, Heredita2 0 5 s (1963) 211. (3) GUSTAFSSON LUNDQVIST, A. , , Hexasticho,U. d intermediuan n m mutant n barleyi s , Hereditas 9_2 _2 (193C) 229.

(4Ï LUNDQVIST, U., "Intermedium and hexastichon matants in barley"»Barley Genetics IV (Proc. 4th Int. Barley Genet. Symp. Edinburgn, 1981) Edinburgh Univ. Press (13&11 908.

101 AGRONOMI GENETID CAN C EVALUATIOF NO INDUCED MUTANTS OF WHITE LUCHAI-112*

P. NARAHARI Bhabha Atomic Research Centre, Bombay, India

Abstract Early mutants induced in the photo-sensitive, tald fine-graineen l d variety White Lucha2 11 i- (WL.112) continued to show promise when tested in the region where the parent variety is popularly grown. Earlines e sucon hn i mutans s e founi b t o t d governed by a gene system different from that of another early, semi-dwarf, long-slender grained an d high yielding line TR-17, s . Several hundred selections combining desirable traits have been obtaine e progencrose th th n sf i d o y involving these two early parents. Differences in culm height, number of internodes and pattern of internode elongation and thickness were observed in the promising reduced height non-lodging mutant f WL.112o s . Studies upto F p in 21 cresses involving 13 mutants of iV.L. 112 and 9 genetic stocks have revealed the following. Among the mutante, two carry the same dwarfing gene sd. as that of Dee-geo-woo-gen while three others have its dominant allele. The remaining eight mutant e governear s y seveb d n single genes tentativel bein. . d gs , y „ designateda d s o t - d s s

common in two mutants and non-allelic to sd ?; one gene sd ^ is non-allelic to sd.; four genes ed ,, e non-alleliar „ e dwarfin d th s o d t can g c d s , s. d gene d^of s non-alleliTR-5i , e gen d on ,s e o t c T Gheng-chu-ei-11"Ô s, d . Amon e remaininth g g genetic __Jv stocks the sd? gene of D66 is non-allelic to sd ,, c. A similarl f Tainan-o „ d s ys i non-alleli 5 f whild o t ce

both d t and d. are present in IR-28 dwarf.

* Research supporte IAEe th Ay db under Research Contrac . 2689/R3/RBNo t .

103 INTRODUCTION

Induction of desirable mutants like reduced height and/or early types in W.L.112 and their promising nature in preliminary evaluations were reported earlier (1,2), A comparatively rapid and convenient seedling height test for Gibberellin (GA) response in rice was described by Narahari and Bhagwat (3) who also used the method to distinguish different induced reduced height mutants of W.L.112 (1). Unlike wheat where induced dwarf mutants show 9 clear-cut presence or absence of GA-response, n rice i GA-responsth e foun8 wa ea varo t dn i y continuous fashion (1,2), thus making it rather fifficul o distinguist e othehth betweer ro e on n dwarf type, based only on this criterion Genetic experiments were, therefore, considered essential to determin e allelith e c natur r otherwiso e e th f o e mutant genes with the known dwarfing genes. The present report deals wite agronomith h c evaluatiod an n genetic analyses of some of the promising early and/ or reduced height mutants of W.L.112.

MATERIALS AND METHODS

The photo-sensitive tall growing indiea variety, W.L.112 s gammit , a ray- induced early and/or reduced height mutants and certain dwarf genetic stocks;all as detailed hereafter, wer e experimentse th use n i d . Evaluation of 85 early flowering and 48 non-lodging dwarf mutant f V»L.11o s d showe ha 2 th nf o tha 9 5 t former with grain yields over 4000 kg/ha and 32 of the latter with grain yields over 3500 kg/ha werf o e some promise (1) promisine .Th g early mutants have since been r locapassefo n lo d testino locationtw t a g s ISindewah d Sakolan i i research e stationregioth n i n - s where WL.11 s populari 2 . Base n duratioo d o eart n - emergenc d planan e t height these mutants wert intpu e o four different groups and tested in Initial Evaluation

104 Trials with randomised block design, three replications t plone t si^, f 5.7o e x x 1.2 0m m , c spacin0m 0 2 f o g 15 cm and fertilizer applications of 20 kg N + 50 kg P2°5 + 50 kg KpO/ha at transplanting and 40 kg N/ha eac t tillerina h panicld gan e initiation stages. Yield data obtained from these trial s subjectewa s d o statisticat e earll th analysis f yo e mutantsOn . , VA-42-32, having short fine grains and lodging habit lik s parenit e crosses wa t d with another early, semi-dwarf, non-lodging and high yielding culture TR-17 (4). The object of this experiment was o studt e geneticth y f earlineso s o isolatt d an s e desirable high yielding recombinants. Thirteen reduced height mutants of W1.112 and 9 genetic stocks, of different height, as detailed in table-1 »were crosse 1 combinations2 n i d . Crosses involving mutants f WL.11o 2 numbered fourteen. They wer crosseo e :(atw ) s among mutants - (1)^A-64-23 x*A-60-26 and (2)/A-69-7 x ^B-60-26; (b) six crosses with sd stocks - (3) TR-17

x/A-42-32; (4) /D-81-9 x I-geo-tFe; (5) D2lV-L7-70-44 x Dee-geo-woo-gen ) EpIV-Lg-75-5(6 ; x I-geo-tze6 ; (7) ifB-Ed-184-3-11 x I-geo-tze; (8) /B-LT-728-10-7 x I-geo-tsejan x crossesi ) (c ds with non-sd.. stock- s

(9)*D-81- Cheng-Chu-ai-11* 9 ; (10) D2-T7lL7-46-20-7x

Gheng-Chu-ai-1 1; (11) tfD-37- x TR-59 , (12) D2-1V-L7~46-

20-7 x TR-5; (13) E2-IV-Lg-74-56-10 x TR-5; and (14) /C- MD-2630-11-9 x TR-5. Crosses involving genetic stocks numbered seven as follows '• (15) Dee-gee-woo-gen x I-geo- tze; (16) K-8 x I-geo-tz«; (17) D-66 x Cheng-Chu-ai-11 ; (18) 1R-28 dwarf x Cheng-Chu-ai-11 ; (19) IR-28 dwarf x TR-5; (20) TR-5 x IR-28 dw&rf;and (21) Teinan- x 5TR-5 . All the crose progenies in P.. and F,-, were studied for pl&nt height character. Care was taken to sow seeds thinly in the nursery bed and to separate the short from the tall seedlings before transplanting so as to avoid possible competition among them in the fieldmeane Th ,. range and/or frequency distribution for height in parents, P.. and Pp were calculated and plotte o interpret d e resultsth t . 105 RESULT D DISCUSSIOAN S N

Yield evaluation of early mutants :

9 teste5 n 198e I th dt eeeso 4f earlwe o 1 2 ny mutant f W1.11o s 2 gave yields r betteequao o t lr than the parent and other check varieties (table-2). These mutants were promote Preliminaro t d y Variety Trials and results of 1985 wet season are yet awaited. Froe resultth m s availabl e reasonablb n o farca s e t i ,y inferred that inductio f earlo n y mutants withoue th t los f parentao s l yield potentia s quiti l e successful.

Breedin r earlinesfo g e combined with other desirable characters :

Progene crosth sf o yTR-1 YA-42-3x 7 s 2wa r emergencestudieea r fo d , j.lant heigh d graian t n type n 198 i d 198 p 4 an F seasont character5d we an I sP n i s respectively r emergencEa . n parenti e e s founb wa so t d within 90 days while in F it was later by about 3 weeks. However2 day 13 F s showeo e transt th ,4 6 d - gressive patter f segregatioo n r thifo n s character (Fig.1). The results indicate that two different gene systems are involved in governing earliness in the parents 0 plantA tota96 . f o sl with desirable character combinations have been selected for further studies. These selections also include plants with duratio emergencr ea o t n e being earlier ro later than bote parentsth h t seemI . s possiblo t e isolate high yielding early lines combining the semi- dwarf non-lodging natur d finTR-1f o ean e7 grain characte /A-42-32f o r .

Non-lodging mutants :

n 198I d 198 4t seasonan 5we 5 shor2 s t non- lodging and 10 lodging resistant reduced height mutants of WL.112 were evaluated for their yield performance and internodal patterns. In 1984 all

106 50 60 70 80 90 100 110 120 130 UO DAYS TO EAR EMERGENCE Pig. 1 Mean. , range and/or frequency distribution for number of days to ear emergence in parents,

e crosth f so TR-1 2 F d 7/A-42-32x an I P .

7400 Non-lodgin (1962 gt stason 11 mutant4W« L W )f o s

7000

6600

6200- C-2 „ 5800- Oi C-4 - 5400- .c

3 5000- UJ z 4600- cc "> 4200-

3800- C-1 3400-

3000-

T l l l l I I I 1 I I I I I I 1 I I M ^ 1 0 70 80 90 100 110 120 130 140 150 160 PLANT HEIGHT(cm)

Fig . 2 Relationshi. p between plant heigh graid an t n yield in 35 non-lodging mutants of W.L.-112 and four control varieties.

107 but three of the mutante yieldea more than 4000kg/ha and in general plant height and grain yields were correlated (Fig.2). Eighteen of these mutants again gave similar high yield n 198i s t eeaeon5we l Al . these mutants ere now proposed to be sent for testing in the region where the parent variety ie popular. The data on culm end p&nicle lengths, internode number and their elongation obtained for the short non-lodging mutant s i summarises depicted an d d average n i Fig.Th . 3e numbe f developeo r d internodes in the short non-lodging mutants ranged between 5.7 and 7 (th8. e maximum observe plany an tn i dbein g 10), e checth n ki 0 8. d s an agains a n '.V.Li 2 11 8 . 7. t variet ye telSK.L-1th e linternodes n th I check . l al s , includin e loweth g r ones, were well developede th ; short non-lodging mutants showed in general reduced length of internodes,more/s n thosi o e belo e thirwth d internode. Some of the mutants , however, showed relatively uniform reductions in all the internodes. The reletive

uo NON-LODGING MUTANT L-112(196&W«W 7 O* S 1 season) ISO ilffiilW

DFFGHIJKLMNOPCR5T' VWXY ZWLJKL

Fig . 3 Relativ. e patter f internodo n e elongation, culm height,panicle length and mean number of internode reduce4 2 n i e d height non- lodging mutents of W.L.112 and four check t SKL)f L varietieW , .Q , (A s

108 contributions of the top two internodes to culm lengthwere generally far greater than 50 per cent in the mutants as against just about 50 per cent in the tall checks. The girth of the top four internodes also revealed similar variations. The first to fourth internodes showed a respective range between 0.90 and 1.30, 1.34 and 2.14, 1.50 and 2.06 and 1.65 and 2.34 cm in the mutants as against 1.12 and 1.17, 1.58 and 1.66, 1.8 d 1.9 6e talan 2.0d th 1 2.1 an d ln 0i an 3m c check varieties.

Genetic f induceo s d dwarf: s

Based on the normal height of the suspected natural crosses, 3 dominant : 1 recessive phenotypic segregation ratio in F£ and 2 segregating : 1 non-segregating familie , mono-geniF_ n i s e receiseive inheritancf o e several W.L.112 mutant phenotypes was inferred earlier (1,2), Similarly preliminary information on TR-5 dwarfing complex accompanied with characteristic cigar- shaped panicle was determined to be governed by d. gene which is independent of sd. gene of Dee-geo-woo-gen (1,2,5). Twenty-one crosses involvin 3 reduce1 g d height mutants of W.L.112 and 9 genetic stocks,as

described earlier, have since been studied in F1 and F? generations e rang e Th f mutantheigho th .e s n i twa s e genetith n i d c an stock m c 5 s 14 betwee betweed an 7 n4 n talm c l9 13 whil m s c e variet wa 1 on e 10 8 K- yd 5an 1 (Table-1). Plant height differences in the parents, F hybrid patternd an s f segregatioo s n theii n r respectiv crosse1 progeniep 2 F e e e seriallth ar s f o s y n fouI depicte r« crosse 24 n Figs i do t 4 s. (Kos. 1,7, vid5 1 ed respectively7 Figsan o t 8 4 . ) height differences among parents were almost absent, F resembled both the parents and the F~ showed unimodal normal segregation curves, thus indicating presence of the common gen erespective paith n i r e parent f eaco sf theso h e

109 TABLE 1. PARTICULARS OF CROSS-PARENTS

(a) Induced mutent f #.Lo s . 112 (b) Genetic Stocke

SI. Plant SI. Gene Plant No. Name Height No. Name Symbol Height (Cm) (CIL!

1. yo-61-9 145 1. Dee-geo-woo-gen edL, 101

2. D2IV-L7- 70-44 138 2. I-geo-tze 8d1 100 3. /i-42-32 124 37 .1 - TE 95 4. /B-60-26 108 Hi . 4. D-66 fid 80 5. j A— b4—O 1I< pOc .u--_-f* 6. /E-Ed-184-3-11 102 5. TR-5 dt 82 7. /D-37-9 101 6. Tainan-5 (non-ed. ) 71 8. /C-kD-26 30-1 1-9 95 Cheng-chu-ai-11 (non-sd.. ) 9. jfE-LT-728-10-7 89 7. 93

10. D2IV-L7-46-20-7 86 8. IK-28 dwarf (double dwarf) 51 11. B IV-L8-74-56-10 86 2 9. K-S (Tall variety) 139 12. B2IV-L8-75-56 84 13. A-69-7 77

80-

70 7 -8 0 l ————————————- —» / 3 9 6 l —————————————• — i 60- - F2 408 o 50- UJ 0 40- LÜ CK U- 30-

20- ^_^J-

10- f^~^^ J— 1 ] _ i i i i i i r i r 0i - t i i i i i i i r 1 40 BO 60 70 80 90 100 110 120 130 UO 150 160 PLANT HEIGH) m T(c

Fig. 4. Mean, range and/or frequency distribution for plan e crosth t f sheigho „ F n parents i td an . ,F. /A-64-2 3i B-60-26 .

110 )TB-Ed-1B4-3-11X I-geo-tz» «S>F1 IL 92 I————•-

uo - <5 83 I——————•————I

F2 719 120 -

H 0 10 £ Ijj 2 80 or ii_ 60 - T

iO -

20 -

0 -i—I—I—I—I—I—I—I—I—I—1—I—I—I—I—I—I—PT—I—I—I—I—I 0 15 O U 0 13 0 12 0 11 0 10 0 9 0 8 0 7 0 6 0 5 0 4 30 PLANT HEIGHT (cm)

Fig . 5 .Mean , range end/or frequency distributior fo n plen te crosth heigh f s o g F n parents i td an . F. , •/E-Ed-184-3-1 1 x I-geo-tze.

yB-LT-728-10-7XI-gto-tit 180 • 160 - IL sL

-A o ai ^ uo- —l — (58 8 * -ni—

120 - F2 815

100-

80 -

60 -

— ' 40 - —

20-

n - ^ ^— , I II Tr — — i 1 — —— i I —— | i —— | —i | i i i 1 i 1 T i r T• 30 40 50 60 70 80 90 100 110 120 130 140 150 PLANT HEIGHT (cm)

Fig. 6. Mean, range and/or frequency distribution for plane th t f heigho F n parentsi td en F , cross /B-LT-728-10-7 x I-geo-tze.

Ill 260- D«o-g«o-woo-g«nXI-g»o-ti« 240-

220- —

200-

180-

160- — -i >- o

140- • 14>F1 IL ~ ^ 120- I S : o -• —— FREQUEf " —I — (5*: Ififl -m- 100- * F2: 783 a 80- —— J

60-

40- 20- 1_

SO 60 70 80 90 100 110 120 130 140 PLANT HEIGHT! cm )

Pig. 7. Mean, range and/or frequency distribution for

plant height in parente, F er.d F? of the cross Dee-geo-woo-ge x nI-geo-tze .

crosses n threI . e crosse0 vid2 ed an s 9 (.Nos1 , 5 . Figs. 8 to 10 respectively) parental height differences were present, F. resembled one of the cross parents and the Fp segregation patterns were unimodal but skewed towards short height, thus indicating single gene pair differences amone parente particulath th g f o s r cross. In five other crosses (Nos.3,4,9,16 end 18 vide i'igs. 11 to 15 respectively) height differences were present among parents, F. resembled one of the cross parents end Fp showed bimodal pattern f segregationo s , thus indicating again a single gene pair diflerence among the

Text continued 117.p. on

112 r~i—i—i—i—i—r—i—i—i—i—i—r-|—i—i—i—l—l—r 70 SO 90 100 110 120 130 140 ISO 160 170 l«0 190 700 210 PLANT HEGHT(cm)

Fig . 8 Mean. , range and/or frequency distributior fo n

plan e crosth t f heighso ? F n parents i td an F ,

D2IV-L7-70-44 x Dee-geo-woo-geji.

IR-28dwzrfXTR-5

i—i—\—i—i—i—i—i—;—i—I—i—r~i 0 12 0 11 0 10 0 9 0 8 0 7 0 6 O S o t 0 3 0 2 0 1 0 PLANT HEIGHTtcm )

Fig. 9» Mean, range and/or frequency distribution for

plant height in parents, F and F? of the croes IR-28 dwar x TR-5f .

113 FI

i— i n—i—l—l—i—i—T-|—i 0 3 0 2 10 60 70 80 90 100 110 120 PLANT HEIGHT(cm

Fig.10. Mean, range and/or frequency distribution for plant height in parents, P end F of the cross 2 TR- x IR-25 8 dwarf.

i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—i—'—i—r 0 20 0 19 0 18 0 17 0 16 0 15 O U 0 13 O 1Î 0 11 0 10 0 9 0 8 0 7 0 6 0 5 PLANT HEIGHTIcm !

Pig.11. Mean, range and/or frequency distribution for ne plant height in parents, P.. and P2 °^ * cross TR-17 x^A-42-32.

114 65 75 85 95 105 115 125 135 U5 155 165 175 185 195 PLANT HEIGHT(cm)

Fig.12. Mean, range and/or frequency distributior nfo

plant height in parents, P.. and F2 of the cross VA-81- 9I-geo-tzex .

rA-81-9X Chtng-chu-ai-11

70 BO 90 100 110 12n 130 UO 150 160 170 180 190 200 PLANT HEIGHT(cm)

. Wean13 . , range and/or frequency distributior nfo

plant height in parents, F.. and F? of the cross /A-81-9 * Cheng-chu-ai-11.

115 LU o:

, 6b 75 85 95 105 115 125 135 US 155 165 175 185 PLANT HEIGH) m T(c

Pig.14« Mean, range and/or frequency distribution for plant height in parents, F, and F of the cross K-8 x I-geo-tze.

180- IR-2Bdw»r(XCh«ng-chu-al-11

uo- n U 120- d* iS. u z 100- LU F2 695 a

60 -

40-

20- i i i i i r~i l i i i i n i i i i 0 10 20 30 tO 50 60 70 80 90 100 110 120 PLANT HEIGHTlcm)

. Wean15 , range and/or frequency distributior fo n plant height in parents, ¥. and P„ of the crose IR-28 dwarf i Cheng-chu-ai-11,

116 parents of the respective crosse s. In the remaining nine crosses (Nos. 2,6,10,11,12,13,14, 17 and 21 vide Figs. 16 to 24 respectively) parental height differred^P.

were distinctly tall and F2 showed rcultimodal and/or transgressive segregation patterns^thus indicating involvemen differeno tw f o t t gen ee respectivpairth n i s e

cross parents. Genotypic segregation 2 familieF n i s s in all the cross progenies are still to be studied for

confirmatio 2 phenotypiF e th f o n c segregation patterns. Even eo the above results do permit the following tentative deductions regarding the genetic constitution r dwarfo r talo f l e heighmutantth f genetid o tan s c stocks. Those having genes allelic to sd.. of Dee-geo-

woo-fie I-geo-tzd ) an /A-42-3nU e ar e 2 ,~7E-81-9, D2IV- IV L8 75 56 an df tneo K-8 1 m a1 carrv L -70-44>B2 " '" ~ - » e it dominant allelic pair (SD SD )jand (b) /B-Ed- 184-3- 11 and /B-LT- 728- 10-7, both of them carry the same recessive allelic pair (sd.. sd..). Non-sd.. stocke ar s

D-66 (sd2 sd2), TR-5 (dt~d~^ ~a~nd sdx, scT7) , Cheng- Chu-ai-1 1 (sd , sd and D~" S~), Tainan-5 (sd „ sd „ ) and X X w X XX IE-28 dwarf (sdx t , d sdfollowin e td )xTh ,.an g mutants are governed by single pair of semi-dwarfing genes in each case : ^A-60-26 and /A-64-23 (both sd h&vin e commoth g n gene pair(sd. d ),^A-69-s . 7 ( x2

t ---

E2IV-L8-74-56-1---- 0 ,

sd /C-MD-263ïïTTl-TTsdd x6an )) and C-MD-263ïïTTl-TTsx d sd). The e mutanth gen f o et DpIV-L7-46-20- e nons i foun7b o -t d . alleligen f d Cheng-Chu-ai-o s e o t c . 11 Whil e th e ___ J\. _ dwerfing gene sd ^ of the mutant KpIV-L8-75-56 ie found

to be non-allelic to the dwarfing gene sd1 of Dee-geo-woo gene relationshipth , e otheth f ro s dwarfing genes with sd. remain to be investigated,

Text continued 123.p. on

117 rA-69-7-XTE-60-26

«FI

l—i—l—i—i—l—l—l—l—l—l—l—i—i—i—l—i—i—i—i—i—i—i—F~-i—l—i—l—l £0 50 60 70 80 90 100 110 120 130 UO 150 160 170 180 190 200 PLANT HEIGHT(cm)

Fig.16. Mean, range, and/or frequency distribution for plane th t f heigho „ P n parente I td an F , croee -/A-69-7 x /B-6C-26«

EJrr-LS-75-MXI-o.o-t».

i i—T—i—i—|—i—i—i—i—i—i—i—i—i—i—i—i—i—i— j i i t 0 19 0 l« 0 17 O IS O IS O U 0 11 0 12 0 11 0 10 0 1 0 » 0 7 0 1 SO PLANT HEWHT(cm)

Fig.17. Mean, ran^e and/or frequency distributior fo n plant height in parente, F and f^ of the

cross E2IV-L8-75-56 x I-geo-tze.

118 D;IY-Ly-*>-10-7XCtnna-chu-

«F1

I—I—I—I—I—I—I—I—I—I—I—I—I—I—I—T O IS 0 18 0 17 0 18 0 1> O U 0 13 0 12 0 11 0 10 0 9 0 » 0 7 0 1 O S 0 » PLANT HEKSHTUm)

F ig.18« Mean, range and/or frequency distribution for plant height in parents, F and F of

e crosth s D2IV-L7-46-2 Cheng-Chu-ai-10x 1

r 0-37-9XTR-S 60

*F1

0 19 0 18 0 17 O IS 0 15 O U 0 13 0 12 0 11 0 10 0 9 0 8 0 7 0 6 O S 0 4 PLANT HEIGHT! cm!

Fig.19» Mean, range and/or frequency distributior fo n

plane croeth tsf o heigh 2 F n parentd i t an F s x TR-5.

119 90-

!0-

70 -

60-

O £ 'o- u.

30-

20-

10 -

-i—i—i—(—i—I—i—i—i—i—i—i—i—i—i—i—I—-Fr l fi—l—i—i—l—l—l—I—r—i—I— r 30 to 50 60 70 60 90 100 110 120 130 UO 150 160 170 180 190 200 PLANT HEIGHTUm I

Pig.20. Meen, range and/or frequency distribution for

plant height in parente, F.. and F? of the cross D2IV-L7-46-20- i 707U5 .

E-,IV-L8-7t-S6-10XTR-5

80-

»Fl

. . , —I—l—I—I—I—I—I—I—I—I—I—I—1—r ...... 5 19 5 18 5 17 5 16 5 15 5 14 5 13 5 12 5 11 5 10 5 9 5 8 5 7 5 6 5 5 5 4 5 3 25 PLANT HEIGHTUm)

Pig.21. Mean, range end/or frequency distribution for plent f o heigh' tnp P en parentsi croed t an e. F , E2IV-L8-74-56-1 x TR-50 .

120 rc-MD-2OO-11-»XTR-5 êO-l

i r i i i i i i i i i— i i i i i i i—n— i i i i i i T—i—i i i i 0 20 M I 0 l« 0 17 O IS O IS O U 0 13 0 12 0 11 0 10 M 0 « 0 7 0 6 O S 0 1 PLANT HEIGHT!cm)

Pig.22. Mean, range and/or frequency distributior nfo plant height in parents, P- and Pp of the cross /C-MD-2630-11-9 x TR-5.

D-66XCh«ng-chu-ai-11

l—i—n—i—i—i—i—i—i—i—i—i—i—i 0 17 0 16 0 15 O U 0 13 0 12 0 11 0 10 0 9 0 8 0 7 0 6 0 5 PLANT HEIGHT! cm)

Pig.23. Mean, range and/or frequency distribution for

plant height in parents, F and F2 of "the CTOSB D-66 x Cheng-chu-ai-11.

121 roman-5XTR-5

80- »Ft 70- a. - >- 60- 2, — u 0 1< I—— —» . ———— | z uj 50- F2 787 o I rA UJ 40- | OL I Ü. _ 30- p „ iJ S 20- H U 10- f-H_l r- _ Lr-J V 0- J LJ 1 — 1 — 1 — I 1 — — 1T— 1 — — 11 — 1~ — — 1 1 — — 1 1 — t — | 1 — 1 — — — I — 111 — — 1 I — — 1 1 l 1 1 i i ii — I — 5 18 5 17 5 16 5 15 5 U 5 13 5 12 5 11 5 10 5 9 5 8 5 7 5 6 5 5 5 4 5 3 25 195 205 PLANT HEIGHT (cm) Fig.24 Mean, range and/or frequency d istrj b\jtion for

plant height in parents, F and ?2 of the cross Tainax 5 - n TR-5.

TABLE 2. PROMISING EARLY MUTANTS OF WHITE LUCHAI-1 12 1984 Wet Season

bl. tout ant Particular ; Days s Plant Panicle Grain Yield/ha (K«) No. Cod. No e i Selection NÛJ to Height Length ~S~ïnde«ahi Sakoli [Average ! S.S. (Cm) ! (Cm) i 2 1 ! ! 3 ! 4 5 ; 6 7 89 ! Group I (16 Mutante •f 3 Checks )

1 ÏSSR-12 *-23(bM-3 98 82.719.5 4239 4799 4519 2 TSSR-15 ^C-ET-4145-12 100 104.7 20.0 3606 4434 4020 1 TbSR-13 /A- 15-8 96 100.7 19.7 3241 4507 3874 4 TbbR-9 /E-23(C)-2 96 128.0 20.7 3289 4264 3776 5 TSSH-2 Sl-Bulk-Ed-14-15 96 129.3 24.3 2364 5092 3728 6 TS5R-6 >'C-BT-23-17-5 94 116.0 22.7 2465 4922 3703 7 TbSR-7 /B-23(C)-10-3 93 U3.3 20.0 2070 4849 3459 8 - Ratna (Ch) 90 89.3 24.0 3922 3241 3581 9 - Kiramoti (Ch) 4 9 117.7 20.0 2144 2899 2521 10 - Sye-44-3 (Ch) 87 90.720. 3 3362 3118 3240

CD/ha - - US NS -

Group II (17 Kutanta + 2 Checke)

1 TSSR-27 A2-I-M-3 98 111.3 20.0 2606 4385* 3495 2 TSSR-19 D2-III-Bd-6 96 117.0 21.1 1948 4630* 3289 3 TSSR-26 A2-III-Bd-7 98 121.7 22.8 2631 3&99 3265 4 TSSR-31 D2-III-Ed-13 99 120.7 20.1 1998 4264* 3131 5 Tfcb'R-17 CA2-Ed-1 95 120.7 21.9 2364 3874 3119 6 SB-3: T 0 A2-I-Ed-2 0 10 122.7 21.6 1925 4166* 3045 7 TbSR-33 /G-3-3 100 123.0 21.1 2387 3630 3008 S TSSR-20 /G-5-1 96 119.0 22.8 1802 4141* 2971 9 - Eiraaoti(Ch) 97 127.7 19.9 2588 3289 2923 10 _ SKI-1 (Ch) 111 115.0 19.7 2168 3606 2887 CD/ha - - US 501 - -

122 TABL 2 E(cont. )

Group III (21 Mutante + 3 Checks)

1 TSSR-38 /A- 5 1-7 109 124. 1 20 .1 3703» 2533 3118 2 TSSR-35 /D-1Û1-17 102 129. 1 22 .4 3660* 2358 2909 3 TiJSR-53 A2-1I-SL-BT-3 114 125. 5 19 .2 3095 2690 2892 4 TÜSR-44 /E-49-12 107 109. 2 18.6 2875 2519 2697 5 TbiJR-3) /A- 11 -2 109 120. 7 19 .3 2758 2606 2682 6 bKL-1(Ch) 112 131.6 19 .5 3606« 1925* 2765 7 Sye-75(Ch) 111 94.0 20 .3 3362* 1973* 2667 8 WL-1 12 (Ch) 112 126. 5 18 .3 2538 2704* 2631

CD/ha - - - 765 407 -

GrouV I p (5 Mutante + 3 Checke)

1 TbuR-55 lfE-58-18 103 124. 6 23.0 3776 1729 275^ 2 R.P.4-14(Ch) 101 81. 5 22 .0 5656* 1633 3594 3 Sye-75(Ch) 111 95.9 19 .4 4265 1267* 2766 4 W.L.-1l2(Ch) 111 116.0 16 .4 3436 1754 2595

CD/ha - - - 860 - -

Source: Punjebrao Agricultural University, Akole, Annual Report Rice - 1984-85. * üignificantly higher or lower thon W.L. - 112.

CONCLUSIONS

Early and/or reduced height non-lodging mutants have been successfully induced in the photosensitive, tall and fine-grained variety W.L.112. Several of these mutants retain the grain character and yield potential of the parent variety. It hae been possible to , selecearlF- n yi t plants combining alse eemith o - dwarf non-lodging character of one parent TR-Î7 with the fine grain character of the other parent yA-42-32 which is an early and reduced height mutan f W.L.112o t . Promising reduced height non- lodging mutants exhibited different culm lengths, internode number d internodan s e elongatio d thicknesan n s patterns. Genetic analysi f reduceo s d height character

123 s beeha n attempte studyiny b d g upt '« tlloF € progenies of 21 crosses involving 13 mutants of W.L. 112 and 9 genetic stocks f theo m8 , semi-dwarfs. Whilo tw e of the mutants carry the same sd.. gene as that of Dee-geo- woo-gen, eight other e governear s sevey b d n seperate single genes tentativel. _ d s y o t designate . . d s s e d One of the genes sd * is common in two mutants and is non-allelic to sd „• Another gene sd ^ is non-allelic to sd.. Genetic composition of the other parents and certain other inter-relationship among dwarfing genes are aleo inferred from the available results.

REFERENCES

1) NARAHARI, P. and BHAGWAT, S.G., Studies on reduced height mutants in rice, In Semi-Dwarf Cereal Mutent n Crosi Theid e en e sUs r Breeding , IAEA-TECDOC-307II , Vienna (1984) 247-258. 2) NARAHARI , ProgresP. , s Repor Cytogenetion o t , physiologi d agronomian c c evaluatio f induceo n d semi-dwarf mutants in rice, Paper presented at the Third Research Co-ordination Meetin n Evaluatioo g n of Semi-Dwarf Cereal Mutants for Cross Breeding, April 2-6, 1984. International Maize and Wheat Improvement Centre (CIMMYT) Ciudad Obregod an n l BatonE , Mexico. ) 3 NARAHARI d BHAGWATen . P , , S.O. rapiA , d seedling tesr gibberellifo t n respons n ricei e , Curr. Sei. 7 JzJ(19821 L ) 64-0-041. 4) NARAHARI, P., JOSHUA, D.C. and RAO, N.S., Semi- dwarf rice mutants and their agronomic evaluation, In Semi-Dwarf Cereal Mutants and Their U.se in Cross Breeding, IAE - ViennA8 TECDO 26 - aC (1982) 85 - 104« 5) NARAHARI, P., TR-5 dwarfing gene in rice, Paper presented at the International Rice Genetics Symposium, 27-31 May, 1985, International Rice Research Institute, P.O 933x .Bo , Manila, Philippines (In press).

124 EVALUATION, INHERITANCE GIBBERELLID AN , N RESPONSE OF INDUCED SEMI-DWARF MUTANTS OF RICE

J.N. RUTGER, T.R. ANDERSON United States Department of Agriculture, University of California, Davis, California, United State f Americo s a

Abstract

The induced semidwarf mutant gene, scL, has been used tu develop nine rice cultivars in California. This induced mutant gen s allelie semidwarfini e th o t c g gen n DGWGi e , T(N)1, 1RS d othean , r Green Revolution cultivars x otheSi . r mutants are non-allelic to sd,. To date, none of these six has been as agronomically useful as sd,, but three warrant further investigatio f genetii n c vulnerability should arise from widespread usage of sd,. Seedling response of genotypes o exogenout s gibberellin "HJA) fell into three broad categories: High response (second leaf sheath length at 1C ppm of GA more than 450% of QJ ntrol), intermediate response (300-450%), and low response (less than 300%). The high response category consisted of Tanginbozu and the semidwarf mutant Short w responsLabellelo e Th e. category consistef o d e talth l indica cu'ltiva e talrth lPetd southeran a S U n cultivar Labelle e remaininTh . g genotypes, includine th g semidwarf indica cultiva o rtal tw DGWG le japonicth , a cultivar , threM5 rosd l e an Ca ejaponics a semidwarfs wite th h induced mutant gene sd1, the indica-japonica derived semidwarf cultivathe~thed an , M9 r r8 induce d semidwarfs, showed intermediate response e majoTh . r semidwarfing gene sd,, whether derived from induced mutatio r froo e DCTfn th m ä source, doet see no o saffect m t GA-respons n japonici e a backgrounds. In contrast n indici , a background , gen sd s associatei ee th s d with increase n GA-responsivenessi s . Trie" implicationA G f o s responsivenes f semidwarfo s n rici s e breeding remain unclear.

1. INTRODUCTION e threTh e agencies cooperatin n rici g e researcn i h California (the Universit f Californiao y e U.Sth , . Department of Agriculture, and the California Co-operative Rice Research Foundation, Inc.) have made extensiv f induceo e us ed semidwarf mutant n rici s e breeding [1] n thiI . s cooperative effore th t first two agencies investigate genetics and breeding methods, including induced mutation, while the last agency takes principal responsibility for cultivar development. Since 1976, two induced semidwarf mutants have been directly release s cultivarsa d , while seven more semidwarf cultivars

125 have been developed by cross-breeding with induced mutants or their derivatives. All nine cultivars carry the sd1 source of semi dwarfism, which is allelic to the major semidwarfing gent in DGWG, T(N)1, IR8, and other Green Revolution cultivars of e tropicsth . Results achieved since 1980 withi e Co-ordinateth n d Rf-search Programme fall Into categoriestw o : inheritancf o e additional semidwarf mutants which are nonallelic to the primar , sourcesd y d determinatioan , e responsth f o nf o e semidwarFmutant o exogenout s s gibberellin (GA) e firs.Th t categor s on-goinwa y g whee Programmth n s beee ha began d an n extended during this period, while the second category was initialed as a result of discussions at the first RCM.

2. INHERITANCE OF SEMIDWARFISM The inheritance and allelic relationships of the several semidwarf mutants produce n Californii d s recentlwa a y reported [2j and hence will be summarized only briefly. Three independent, recessively inherited semidwarf genes, sd,, sdd ?an , sd,, were induced in the original nutagenic treatments of the tail cultivar Calrose. Following the elucidation of the allelic relationships among these thre , esubse 4] gene , -[3 s quent studies with new mutants were concentrated only on determinin e allelith g c relationshi , referencsd e th eo t p source. Thus four additional induced semidwaTrfs are now known to be nonullelic to sd, (Figure 1). These semidwarf mutants

CI 11046 I 1104C 9 Short C1M045 (M5) (Calrose) Lobelle (M5) (Lobelle)

Calrose 76 (Calrose) CIll035(Coluso) M-40l(Terso) DGWG

CI 11034 023 CI II033 025 (Calrose) (Calrose)

Figure 1. Allelic relationships of induced semidwarf mutants and DGWG. Genotypes at the same corner of the triangle are allelic; thos t differena e t corner nonallelice ar s . Genotypes in the "fan" at top are nonallelic to the sd, locus but their relationships to other loci are unknown. Parent cultivars are shown in brackets. From Rutger et al. [2].

126 and their tentative gene symbols are: Short Labelle; t c s^ , CI 11049, sd,.; CI 11045, sd?_.; and CI 11046, sdg_t. The sd. gene, whicn reduces heigïït about 25 cm and lëaas to 15-20% yield increases, has been the most agronomically useful semidwarf source * .sourc sd Thue eth s reduces height onl5 1 y cm instead of the desired 25 cm; the sd. source likewise reduces height only 15 cm and has an Additional pleiotropic affect for a 20% reduction in seed size; and the sd,- , gene has a pleiotropic effect for short narrow leaves a"ha reduced seed size. The sd^ ,, sd? ., and sdp . genes produce the appropriate neigTvt reductio d see an o nhavt m e littlo n r o e harmful pleiotropic effects; however ,non yieldes ha e d more than their respective tall parent [41. A peculiarity of the Short Labelle mutant is that it shows considerable sterility when backcrosse s talit l o t parentd , although Short Labelle itself is fully fertile [5]. Whether these latter three semidwarfs would benefit fro a m"cleanin " procesup g f o s crossing into other background t knownno t shouls i sbu ,e th d . sourcsd e ever prove genetically vulnerable, these three will certainly receive greater attention.

. 3 GIBBERELLIN RESPONSE 1 Introductio3. n Dwarf gene sources in cereals have been known to exhibit differential culm elongation responses to gibberellin (GA) at least since 1956, when Phinney [6] reported such differences in maize. Following discussions at the first RCM about the non-responsivenes e widelth f o ys used Norin-10 semidwarfing gene wheatn i s e decide,w o investigatt d A responsG e th ef o e r induceou d semidwarf mutant n rice i se wer W . e particularly interested in determining if the most useful induced mutant gene, sd,, showe y uniquan d A responsG e e pattern. Previous wor y otheb k r researchers indicate , sourcdsd thae eth t derived from DGWG was GA-respcnsive in indica~5ackgrounds [7, 8] but not in japonica backgrounds [9]. 2 Material3. d Methodan s s Four experiments were conducted to determine response to exogenous GA of 12 induced semidwarf rice mutants plus appropriate dwarf, semidwarf, and tall controls, using the procedure outlined by Harada and Vergara [7]. GA response was expresse e e secondarlengtth th f y o b hd y leaf sheata s a h percentage of its control (treatment/control x 100 = GA response). Tanginboz d DGWan u G were include l foual rn i d experiments as standard GA responsive dwarf and semidwarf genotypes, respectively e induceTh . d semidwarf mutant Short Labelle als s include wa ol fou al r n i experimentsd . Experimen 1 includet d five genotypes e ancestryTh . , plant type, and semidwarf allele of these and subsequent genotypes are shown in Table 1. Rice seeds were surface sterilized in 2.62% sodium hypochlorite for approximately 15 minutes, rinsed several times with distilled water, placed in

127 Tabl . 1 Ancestrye , plant type, semidwarf allele d lengtan , h f secono d leaf sheat2 induce1 f o h d semidwarf mutants2 , semidwarf cultivars, 1 dwarf cultivar, and 4 tall cultivars of rice used in GA-response studies. Genotype 7\nces- Plant Seirn dwarf A responsG e try3 type allele category0 Experiment 1 2 3 4 DGWG I s «LI I I I I Peta I T L Tanginbozu J D H H H H Short Labelle S IS sd,- , H H H H Labelle S T — o-t L L Cal ros6 7 e J IS sli I I

Cal rose U H T I I I T M9 I/J S sd i M5 J T 1 I M-401 J IS sd I I CI 11033 J IS sdp I CI 11034 J IS scf^ I CI 11035 J IS ?37 I CI 11045 J IS 1^7-t I CI 11046 J IS sdQ I CI 11047 J IS UnKnown I CI 11048 J IS Unknown I CI 11049 J IS sdc I CI 1105C J IS UnKnown I

I - indica, J = japonica, S = southern US type, I/J = , indica-japonica, backcrosse o japonicat d . S = semidwarf, T = tall, D = dwarf, IS = induced semidwarf. H = high response (second leaf sheath at 10 ppm of GA more than 450% of control), I = intermediate response (300-450% of control), L = low response (less than 300% of control).

glass petri dishes containing #2 Whatrran filter paper with 5 ± 8 0 hour4 f 3 distillemo e darlr t a th sfo kn i t d se wate d an r 2 C. The uniformly germinated seed were transferred to 20 x 12m glasm 5 s test tubes 8 ,seed r tubepe s , containinl m 5 0. g solutions of GA., at concentrations of 0 and 10 ppm, and covered with transluscent plastic caps. Six replications were used n randomizei , d complete blocks e tesTh .t tubes were place n continuoui d s light 0 microeinstein18 , ~ secm t sa ~ l m 5 e thir 0. d th sixt an y n d O da h . planC 2 t± level0 3 t a , f distilleo d wate s adde wa ro eact d h test tube. Measurements e seconth f do leaf sheath wer ee elevent taketh n y o aften da h r initiatio e experimentth f o n .

Grade 111, 90% minimum GA-, provided by Sigma Chemical Co.

128 Experiments 2, 3, and 4 were conducted over subsequent two-week intervals n similai , r fashio o Experiment n , wit1 t h change tes) it st genotype s notea s n Tabli d . 1 e

3.3 Results and Discussion In Experiment 1, the cultivar Tanginbozu showed the expected high respons e onl A (FigurTh G y o . t indice ?) e a cultivar e experimenth n i s t showed response pattern n lini s e with previou n thae semidwari sth t , report8] , f [7 scultiva r DGWG showed more response thae talth nl cultivar Petae Th . most interesting responses were shown by Short Labelle, which e mosth ts responsivwa e genotyp e experiments th it n i ey b d an , tall parent, Labelle, which was relatively non-responsive. In this and subsequent discussions, genotypes will be categorized as having high response to GA (second leaf sheath length at 10 ppm of GA more than 450°/> of control), intermediate response (300-450 f control)"o w responslo d an , e (less than 3007f ,o control). GA response, %

600 r Lobell. S • e

500 1 Tonginbozu

400

LSD 5 0 »DGVVG 300 • Lobelle

200 Peto

100 0 10 20 30 40 Length of 2nd leaf sheath of control,mm

Figure 2. Relative elongation responses of second leaf sheath to 10 ppm of gibberellin of genotypes in Experiment 1.

In Experiment 2, Short Labelle and Tanginbozu again were e mosth t responsive entries (Figur . 3) eDGW G showed aboue th t same intermediate leve f responso l n Experimeni s a e . 1 Thret e other semidwarfs, M-401, M9, and Calrose 76, all of which posses e sam, th slocu sd e s DGWGa s , showed responses similar o DGWGt talTcultivae Th . r Calrose also showed response simila o DGWGt r . Calros Calrosd an e provid6 7 e n interesta e -

129 GA response% ,

LobeliS - e 600r

• Tonginbozu

500-

• M-401 • Colrose 400- •M9 r • DGWG •Colros6 e7 LSDOS 300 -

200 -

100 0 10 20 30 40 Lengtho lead f2n f sheathof control,mm

Figure 3. Relative elongation responses of second leaf sheath to 10 ppm of gibberellin of genotypes in Experiment 2.

G A response, %

600r

Tonginbozu 500 • S Lobelle

400 • CIII050 CIII048 CI 11049.1.^1.047 LSD OS CIII035- :VClrc°o1r5ose CIII034^f «0111046 300 CL 11033 DGWG

200

100 0 4 0 3 0 2 0 1 0 Lengthof 2nd leaf sheath of control, mm

Figur . e4 Relativ e elongation response f secono s d leaf sheath f gibberellio m pp 0 1 f genotypeno o t n Experimeni s . 3 t

130 ing comparison n thae i ,latte th a tsemidwar s i r f mutanf o t the former, and that their GA responses are nearly identical. , gen n sd thiThusi e e s th ,japonic a backgroun o distincn s ha d - tive effect? on GA response. In Experiment 3, Short Labelle and Tanginbozu again were the most responsive entries, althoug e responsth h f Shoro e t o previoutw s pronouncee a th t Labell sn no i experi s s a dwa e - ments (Figure 4). DGWG again showed an intermediate response level. The remaining semidwarf genotypes, and the tall cultivar Cal rose, all gave intermediate level responses which were nearly indistinguishable from each othe d froan rm DGWG. Include n thii d s intermediate group were the induced semidwarf mutants CI 11033 and CI 11034 which carry the sd? and sd. genes, respectively. Another member of the intermediate group, CI 11049, also is a non-allelic (to sd,) semidwarf mutant from Cal rose. Yet another member, CT11035, which is an induced semidwarf mutant :rom the tall California cultivar Colusa, has the sd, gene.

GA response,% S• . Lobelie r 0 60

500 • Tonginbozu

•Colros6 e7 400 •Colrose

I LSD'.05 300 'Lobelle

200

100 0 10 20 30 40 Lengthof 2nd leaf sheothof control, mm

Figur . 5 eRelativ e elongation response f secono s d leaf sheath to 10 ppm of gibberellin of genotypes in Experiment 4.

In Experiment 4, Short Labelle and Tanginbozu again were e mosth t responsive entries d DGWan ,G again showen a d intermediate response level (Figure 5). Calrose 76 and its tall parent Calrose also wer ee intermediatagaith n i n e group and showed nearly identical responses to each other. M-401, an induced semidwarf mutant from the tall cultivar Terso, also carries the sd, gene and falls in the intermediate group, as doee talTcultivath s tale Th l . cultivaM5 r r Labelle shewea d lower response level, as it did in Experiment 1.

131 An interesting finding in the present experiments was thae induceth t d semi dwarf mutant Short Labell s highlwa e y GA-responsive, exceedin t leasa r o tg being equa o Tangint l - bozu, which is the standard high-GA-response cultivar for GA tests. Short Labelle has been yield-tested in the southern U.S., but does not yield more than its tall parent [5], As noted earlier, Short Labelle has the semidwarfing gene sdç ., whic s non-allelii h o sd,t c . A principal conclusion from these four experiments is thae induceth t d semidwarf mutant gene n japonici s a backgrounds, sd,, sd?, sd., sd,.., sd? ., sdR , and three unknown gene sources^CTllOTTTCI 11048, ana'fl 11049) show the same intermediate GA response levels as do tall japonica cultivars. Thi s particularli s y noticeablwhic, , s sd ha h r fo e been widely used in California breeding programs~and which is at the same locus as the semidwarfing gene from DGWG, T(N) 1, IR8, and other Green Revolution cultivars. By contrast, in indica backgrounds it has been reported [7, 8] that cultivars with the sd. gene are more GA-responsive than tall cultivars. The semidwarf DGWG versus tall Peta comparison, both of which are indica cultivars, in Experiment 1 of the present studies, confirmed those earlier findings. Thus, it appears, that the GA response of the sd, locus is dependent upon background genotypes. Even when the sd, gene was backcrossed into the japonica background from IRÏÏ tc produce the semidwarf cultivar e semidwarth , M9 f maintaine s intermediatit d A responsG e e level , which was not noticeably different from the intermedi- e GA-responsat ee tal th level f japonico l a cultivar Calrose (Experiment 2). Similar results were noted by Matsunaga et al. [9], who found little difference in GA-response between semidwarfs, developed by backcrossing the semidwarfing gene from T(N)1 into the tall japonica cultivar Norin 29, and the tall cultivar itself. The implications of GA-response of semidwarf n rici s e breeding remain unclear.

REFERENCES

] RUTGER [1 Adv, N. . J , Agron (1983i 36 . ) 383. [2] RUTGER, J. N., AZZINI, L. E., BROOKHOUZEN, P. J., "Inher- itanc f semidwaro e d othean f r useful mutant genen i s rice" (Proc. First Int. Rice Genetics Congress, IRRI, Philippines) Los Banos, Philippines (1985) in press. [3] RUTGER, J. N., "Use of induced and spontaneous mutants in rice genetic d breeding"an s , Semi-dwarf Cereal Mutants an dCross-breedinn i Thei e Us r g (Proc t Res1s . . Coord. Meeting, Vienna, 1981) IAEA-TECDOC-268, Vienna (1982) 105. ] RUTGER[4 , "GenetiN. . agronomid J , an c c evaluatiof o n induced semidwarf mutant f rice"o s , Semi-dwarf Cereal Mutants and Their Use in Cross-breeding (Proc. 2nd Res. Coord. Meeting, Davis, California, 1982) IAEA-TECDOC- 307, Vienna (1984) 125.

132 ] MCKENZIE[5 , RUTGER Cro, S. N. . p K , . J ,Sei 6 (19862 . n )i press. [61 PHINNEY, B. 0., Proc. Nat. Acad. Sei. 42^ (1956) 185. ] HARADA[7 VERGARA, U (1971 _ , J. Croi S. Se p). B ,373 . [8] SONG, Y., HARADA, J., TANAKA, T., Int. Rice Res. News!. 6_ 1 (1981. )3 ] MATSUNAGA[9 , KARUYAMAK. , , IKEHASHIK. , , Oryz_ H. , 18 a (1981) 208.

133 MUTATION BREEDING FOR SEMI-DWARFISM IN BARLEY*

S.E. ULLRICH . AYDIA , N Departmen f Agronomo t Soilsd yan , Washington State University, Pullman, Washington, United State f Americo s a

Abstract

Mutation breeding has been an important part of the barley breeding effort for reduced height and lodging resistance at Washington State University. Between 1980 and 1985, 264 sodium azide induced putative semi-dwarf mutants have been selected in the M2 from 19 spring genotypes. Most have been discarded due to serions defects. Fifteen mutants were chosen for genetic analysis and agronomic evaluation to determine their usefulness r cross-breedinfo r eveo g s potentiaa n l cultivars n additioI . n to reduced culm length (65-88% vs normal), most mutants had simila r reduceo r d culm diameters, whil e mutanon ed largeha t r culm diameters compare o theit d r normal isotypes. Coleoptile lengths varied similarly f theso x eSi mutant. e presentear s d here s representativa e rangth f mutanto ef o e s studied l mutantAl . s appea o carrt r a singly e recessive genr semi-dwarfo e f ism. Most non-allelic mutant crosses gave 9:7 F2 ratios, while one combination produce a doubld e dwarf indicating additive gene interaction. Two of the mutants are erectoides (er t) types, and the rest appear to be sdw, semi-dwarf types. An incomplete diallele cross series revealed some allelic mostlt bu , y non-allelic gene relationships. Mutant agronomic performance was variable, but most mutants were lowe n yieli r d than their respective normal isotypes e nutantTh . , Mol% highen 'Morexi 19 , n yiels i r 'wa d than Morex. Kernel quality (density, plumpness) tende e lowee mutantsb th mosn o i t rdf o t . Lodging was reduced in most mutants but not in all. Whereas some of the mutants appeared to be improved for several agronomic traits suc s lodgina h g resistance, yiel d earlinesan d s none combined all the traits necessary for a new improved cultivar. The n 'Larkeri 2 L Morexn i d '4 an shoul Mo mutants d e gooan b d l d ,Mo parents for cross-breeding especially for lodging resistance or earliness. Cross-breeding should eliminate deleterious mutation effects and put the serai-dwarf genes into more suitable genetic backgrounds.

INTRODUCTION Breeding for reduced height in barley (Hordeum vulgäre L.) to primarily reduce the risk of lodging in commercial production remain n importana s t objectiv n barlei e y improvement programs around the world. This is especially true in areas with high rainfal r irrigateo l d production .e source th Mos f o f tseraio s -

* Scientific Pape . 732No r 2 Colleg f Agriculturo e d Homan ee Economics Research Center, Washington State University, Pullman, Washington, U.S.A., Project No. 1006. This research was carried out in association with IAEA under Research Agreement No. 2690/CF.

135 dwarfisra use n barleI d y breeding programs originated from induced mutations. Although some semi-dwarf barley mutants have been released directly, many have been modified by cross-breeding before release as commercial cultivars. Subsequent to their release most semi-dwarf mutant cultivars have given ris o othet e r cultivars through cross-breeding. See Konzak et al. and Micke et al. (1,2) for recent reviews. In addition to using a number of previously described spring and winter semi-dwarf barley mutan d cultivaan t r sources (eg., 3 n pedigrei ) d recurren7, an e, 6 , 5 t, 4 selection breedinge th , Washington State University (WSU) barley breeding progras ha m been involve n inducei d d mutagenesis with several locally adapted cultivar d breedinan s U gmutatio WS lines e Th .n breeding program in genera s involveha l e inductioth dw mutants ne f o n , agronomic evalution, genetic analysis and use of selected mutants in breeding. e emphasiTh s bee ha n sproanthocyanidin-freo n a qualit( e y factor) (8) and semi-dwarf (9, 10, 11) mutants. Knowledg e agronomith f o e c performance combined with knowledge e numberoth f , actio d interactioan n e dwarfinth f o n g genea f o s pool of induced mutants is very important for the efficient selection of parents for cross-breeding. With this in mind, the objective herein o reviet U semi-dwar WS e s progres i ,e th w th f o sf barley mutation breeding progra y considerinb m e variouth g s aspects of the program (listed above) with an emphasis on the agronomic and genetic evalution of a selected group of induced mutants. This report updates three previous , 11)report10 ., (9 s

MATERIALS AND METHODS Mutant Induction l mutanAl . t selection occurree th n i d 2 generationM , space planted from bulk-harvested e fielM^'th dn i s at Pullman, WA. Sodium azide was the mutagen applied at a concen- tration of 10~3 M at pH 3 for 2 h to presoaked seeds. This paper gives results fro year6 m f selectioo s n beginnin n 1980i g e .Th progenitor barleys have been malting 2-row and 6-row types from primarily western, but also midwestern North American adaptation (see TABLE I). Genetic Analysis. Eighteen putative mutants in 9 genotypes selected in 1980 and 1982 were chosen for genetic analysis and agronomic evaluation in 1984 and 1985 in Pullman, WA after preliminary evaluations. Crosses were mad n 198i e 4 among semi- dwarf mutants and with their normal isotypes or other normal height genotype o determint s e allelisra, gene numbe d genan r e action and interaction. Parents, F^'s and F2's (from greenhouse propagation) were planted in the field in 1985. F^ and ?2 populations were space-plante m long 3 ,d n rowan i d 2 s respectively, with parent rows flanking each population. Culm lengt s determinewa h y averaginb d 3 e e lengtth th g f o h tallest tillers, measured from the base of the culm to the base e spikeoth fr eac fo ,h individua2 ¥ le parent d planth an n i j tF , populations. Allelis s determinewa m y comparinb d e culth gm lengthf o s FI'S, F2Ts, mutant parent e normas wela sth s thaa lf lo t isotypes for each cross by pooled t-test. Gene number, action and interaction were determine y appropriatb d e chi-square testr fo s all segregating populations. Height classes were determiney b d considering mutan d normaan t l isotype mean d rangean s r culfo sm length.

136 Agronomie Evaluation. The 18 putative semi-dwarf mutants mentioned above along with their respective normal isotypes were planted in replicated yield trials in 1984 and 1985 in Pullman, WA using conventional farming practices. The design was randomized complete block with four replications. Each plot consiste4 f o d rows 3 m long with 30 cm row spacing. Data were collected on culm and spike length, days to heading, physiological maturity, lodging, tillering, grain yield, harvest index, volume weight, kernel plumpness, internode numbed an r length, culm diameter, sterilit d graian y n protein. Only culm length, culm diameter, day o headingt s , grain yield, harvest index, volume weight, kernel plumpnes d lodginan s g date ar a reported here. A full account of the genetic and agronomic experiments can be found in Aydin (12). Culm lengt s measurewa h d from main culm5 randoml f o s y selected plants/plot from the ground to the base of the spike and culm diameter from these 5 main culms at the basal internode with a vernier calipers near harvest time. Days to heading were determined from the date of planting to when 50% of the plot was headed. Grain and shoot yields were measure o centedtw froe rth m rows (hand cut) of each plot. Harvest index was calculated as the ratio of grai o totat n l shoot weight. Wolume weigh d kernean t l plumpness n 2.8x1.(o m sievem 9 ) data were obtained frokernele th m n o s a volume weight machine and timed sieve-shaker device, respectively. Lodgin s measure e wa perceng th s f lodgea do t d culma plo t n a i ts harvest maturity. Data were analyzed by analysis of variance and LSD.05. An experiment was conducted in the laboratory with seed from the 1984 field experiment to determine gibberellic acid (GAß) response and coleoptile length using the Myhill-Konzak (13) seedling culture technique. Twenty-two seedlings (11 GA3 treated, 11 untreated) of each mutant and normal isotype were grown 7 days in complete darkness and 7 days in light with 1/4 Hoagland solution and 10 ppm GA3 in treated cultures. After the 14 days, seedling heights were measured. Coleoptile lengthe untreateth f o s d seedlings were also measured. Comparisons between mutand an t normal isotypes were made by paired t-test. JBree_dijlg.« Selected mutants and/or their cross-bred progeny have been use s parenta d a basicall n i s y pedigree syster fo m maltin d feean g d type maln f barlei o s ed sterilan y e facilitated recurrent selection (14).

RESULT D DISCUSSIOAN S N Mutant Induction. year6 Ovee th sr since 4 putativ198026 , e semi-dwarf mutants induced in 19 cultivars or breeding lines were selecte ds plante A singl(TABLwa w . f eaco ro deI) E h putative mutant in the year after selection to increase the seed and make n initiaa l evaluatio n comparisoi n n wite respectivth h e normal isotypes (progenitors). Selected mutant lines were entered into preliminary yield trial followine th s g year (TABL. I) E In most case a slarg e attrition occurred. Some putative mutant e reduceb o t n height sn i generaldt i turneno d t ,an ou d, the majority of induced mutants showed severe defects in fertility, yiel d othean d r character f agronomio s c importance. Undoubtedly a number of deleterious mutations usually occur simultaneously with each desired height reducing mutation. Neverthless, several mutants have emerge s parentaa d l materia r cross-breedinfo l g which is described below.

137 TABLE I. Putative sodium azide-induced semi-dwarf spring barley mutants selected between 1980 and 1985 and their disposition.

Progenitor Mutants Yield trial cultivar/line Type selected entries M 1980 1982 Advance 6-row 32 12 Morex 6-row 10 2 WA 9037-75 2-row 28 4 WA 9044-75 2-row 30 5 1981 1983 Crée 6-row 3 0 Dickson 6-row 7 0 Manker 6-row 29 3 Andre 2-row 2 0 1982 1984 Morex 6-row 5 5 Manker 6-row 1 1 Larker 6-row 4 4 Norbert 2-row 2 1 Harrington 2-row 1 1 WA 10698-76 2-row 3 1 Klages 2-row 2 0 Bonanza 6-row 1 0 1983 1985 Advance 6-row 10 4 Morex 6-row 15 1 Robust 6-row 20 1 Andre 2-row 15 2 Lamont 2-row 18 2 Klages 2-row 2 1 1984 1986 Hazen 6-row 9 5 Clark 2-row 4 2 WA 8822-78 2-row 4 2 Harrington 2-row 1 1 1985 1987 Hazen 6-row 4 ? Andre 2-row 2 ?

Eighteen of the putative mutants after preliminary observation were selecte r genetifo d c analysi d agronomian s c evaluation. Thre f theso e e appeare o carrt t a ygenr reduceno d fo e d height. e remaininTh e describear 5 1 gA mutan n TABL i d . n 'Morexi tII E ' n 'Norberti e on e erectoided ar ' an s (_er_t_) types, whil e otherth e s are probabl w typessd y . Mutant culm length reductions range % compare35 do t fro 2 d1 m to their respective normal isotypes. Culm diameter can be an important character for lodging resistance, and was unfortunately e mutant lesth mosr f fo so t s compared wite normalth h5 t ,bu mutants were unchanged, and one Morex mutant (Mo4) was larger in diameter than Morex. Coleoptile length is commonly less in semi-

138 TABLE II. Description"1" of induced semi-dwarf spring barley mutants selected for genetic and agronomic evaluations,

Probable Culm Culm Coleoptile Heading Isotype gene length diameter length dats v e Mutant Normal type M vsN M vsN M vsN normal -cm- — %— —mm— — %— -mm- -%- -d- 6-rows Al Advance sdw 53 78* 3.0 95 38 81* -1 A2 Advance sdw 52 76* 2.8 89* 37 79* +1 Mol Morex ert 58 72* 3.7 96 41 89* +8 Mo2 Morex sdw 67 84* 3.8 98 42 91* 0 Mo3 Morex sdw 67 84* 3.8 98 42 91* 0 Mo4 Morex sdw 52 65* 4.1 106* 36 78* +1 Mal Manker sdw 65 82* 4.1 100 35 85* -1 LI Larker sdw 71 83* 3.5 92* 44 110* -1 L 2 Larker sdw 62 72* 3.0 79* 45 112* -5 L3 Larker sdw 63 73* 3.1 82* 46 115* -5 L4 Larker sdw 65 76* 3.2 84* 44 110* -5 2-rows WA371 WA9037-75 sdw 66 85* 2.7 92* 31 82* 0 WA441 WA9044-75 sdw 56 76* 2 .8 93* 43 105 -1 Nl Norbert ert 62 85* 3.2 100 29 103 + 1 HI Harrington sdw 56 88* 2.8 85* 23 70* +1

* Significant mutant-normal differences determined by LSD.05, except coleoptile lengt y paireb h d t.Q^-test. Heading date data were not analyzed.

+ Baseyea2 n ro d averages from field, except coleoptile length.

dwarf cereals compared to normal. Mutant coleoptile lengths in this group of barley mutants ranged from 7(1 to 115% compared with the respective normal isotypes 9 mutant; d shorterha s equal2 , , and 4 mutants had longer coleoptiles than their normals. The coleoptile lengths of these mutants may or may not be a factor in field emergenc , 10)9 , . (3 eRespons o gibberellit e c acis ha d bee f intereso n n semi-dwari t f cereal studies l mutanAl d . an t normal isotypes n thirespondei s3 GA study o t d . Heading dats wa e little affected in most of the mutants, but Mol in Morex was 8 days later than More d threan x e Larker mutant ) swer L4 (L2 5 e, L3 , days earlier than Larker e variabilitTh . y among these mutants e traitfoth r n n somTABLi i s eI I E case e a facto th s i sn i r agronomic performance of the mutants as described below. Six of these 15 mutants were selected for the genetics and agronomic discussion o simplift s e presentationth y d becausan , e thes6 e represent the range of réponses well and probably contain the best candidate r furthefo s r breeding work. Further detaild an s al e founlb datAydin n i d ca a n (12). Genetic Analysis. All mutants examined appear to carry a single recessive gene for semi-dwarfism. All backcross and other mutant/normal height genotype cross progency were normal height ^ (12 F d segregate e )an ith n 1 (norma3: d lsemi-dwarf: 2 F e th n )i (TABLE III). The mean culm lengths of the F^ populations from one pair of reciprocal crosses was significantly greater than the

139 TABLE III. Culm length distribution and chi-square analysis of F£ populations from induced semi-dwarf barley mutants crossed with normal height genotypes.

r fo 2 X Cross Normal Semi-dwarf Total 3:1 P plantf o . — — sNo — —

0 Advance/A6 l 28 2.1819 .25-. 10 Al/Advance 57 24 81 0.9259 .50-. 25 Ant531+/Mol 44 15 59 0.0056 .95-. 90 Morex/MoA 35 13 48 0.1111 .75-. 50 0 3 Larker/L2 12 42 0.2857 .75-. 50 WAA41/WA9044-75 28 14 42 1.5556 .25-. 10 WA441/Morex M* 32 9 41 0.2032 .75-.0 5 4 3 Nl/More * xM 11 45 0.0075 .95-. 90

Morex M-t/Nl 43 18 61 0.6612 .50-.25

+ Morex proanthocyanidin-free mutant of normal plant height.

A More+• x "mutant" line derived fro a msingl 2 planM e f normao t l plant height.

normal parents mean culm lengths (Morex M/NI, Fp 61, 52, 64 cm, respectively and Nl/Morex M, Fp 55, 64, 75 cm, respectively) presumabl o heterosit e 6-roe th du y s wa sMore d 2-roan x w Norbert ert mutant genotypes vary considerably. Most mutant/mutant intercross F2 progeny segregated in a typical two gene fashion giving acceptable 9:7 ratios (12). The three recessive genotypes aaBB, AAbb, aabb wert usuallno e y distinguishable. Double récessives particularly were not discernable. However, an apparent double recessive plant was recovered in the ¥2 population from a cross between the two ert mutants, Nl/Mol (24:22:1 for 9:6:1 y2=2.5886, p=.50-.25) indicating additivity between the two genes. The double dwarf culm length was only 25 cm, while the rest of the population ranged between 36 and 81 cm. Allelic relationships are presented in TABLE IV. The only known allelis x mutantm si amon e th sg emphasized herei s betweei n n . SeveraL2 d Aan l l mutants have been e shownon-allelib o t n o t c each other and several combinations are yet to be tested. Agronomic Evaluation. Agronomic performanc s variablwa e e amon mutante th g s (TABL . MutanV) E t grain yiel s generallwa d y lower than that of respective normal isotypes. However, the mutants Al and L2 were statistically equal and Mol was higher in yield than Advance, Larke d Morexan r , respectively% 19 e Th . increase in yield of Mol compared with Morex is quite high. However, the comparison involved only two trials. The difference in yield between mutant and normal can not be attributed to a difference in harvest index in this case as might be expected. Harvest index varied considerably among the mutants; from .33 to e norma o 113th t f 2 o %l8 r isotype.o 2 .5

140 TABLE IV. Allelism relationships among induced serai-dwarf mutants of barley. Se'mi-dwaVf" "-—'--- — --—-----—- — - - — - —- - -^--—^- — -. — --. I H l N 1 44 1 37 4 L 3 L 2 L I L l Ma 4 Mo 3 Mo 2 Mo l Mo 2 A mutantl A s

A_l_ / /_ + _"' A_2_ / + ~Mo_lJ ^ Mp2_ _Mo3_ AA MpV "**" Lllîil AA AA AA _+_ Ll ~AA~ AA ~A~A~ AA T M AA LJL . L-4- AA WA171_ AA AA - ? / -? WA_4_41_ "__Nl AA AA AA Hi" AA AA

+ Allelic. - Non-allelic. x Allelic by inference based on other allelic relationships. / Non-alleli y inferencb c e base n otheo d r allelic relationships. * Cul* m height difference .01= p )( s between Fj^/F s Parents/Normav 2 l Isotype n non-allelii s c situations determine y pooleb d d t-test.

TABLE V. Agronomic characterization of selected induced semi-dwarf barley mutants, Pullman, Washington.

yield/ Harvest Volurne Plump Isotype plot+ index"1" wei8ht* kernels* Lodging* Mutant Normal M vsN M vsN M N M N ~~M N —g— — A— /Q— —Kg/hi— — — 7» ———— —

Al Advance 496 89 .50 102 61 61 37 50* 40 58 Mol Morex 574 119* .49 102 58 63* 52 71* 25 86* Mox 4e r o M 318 66* .41 85* 61 63* 73 71 23 86* L2 Larker 544 101 .52 113* 59 65* 46 80* 68 50 WA441 WA9044-75 439 77* .33 82* 64 69* 30 88* 0 33* Nl Norbert 467 85* .37 97 59 64* 96 94 0 10

* Significant mutant-normal differences determined by LSD.Q5, yea2 r+ averages, 1985d 198an 4. * 1985 averages only, except lodgin n 198i g 4 only.

141 Volume weight and kernel plumpness were generally lower in the mutants compared to their normals. Kernel density and size assortment did not seem to correlate positively with yield. The highest yielders tended to have the poorest kernel characteristics. e o trias t Lodginoccuth n no d 1985i n ldi i d r di t g, bu relatively severely in 1984. The mutants were generally more lodging resistant than their normals. In the case of Mo4 it t leascoula e b td partially explaine n increasa y b d n culi e m diameter as well as decrease in culm length (TABLE II, V); lodging 25%*, culm length 65%*, and culm diameter 106%* of Morex, the normal isotype. On the other hand L2 had lodging 136%, culm length 72%* and culm diameter 79%* of Larker, the normal isotype. e tren s Th similawa d t oppositebu r . Combinin e datth ga from TABLES II and V, one can see that straw strength is related to more than just culm length, and not only culm diameter, but internode length and probably chemical composition and configuration as well. e numbeTh f internodeo r s t var(sixno yd )amon di mutante th g s or in the mutants vs normals. Height reduction in the mutants occurred because of shorter internodes. The greatest shortening percentagewis o internodee tw occurre e th n i sd neares e basth f to e the culm. The greatest shortening in absolute numbers occurred e uppermosith n t internod r pedunclo e e (12).

CONCLUSIONS AND BREEDING PROGRESS e selectioTh f reduceo n d height mutant n barlei s y induced with sodium azid s relativelwa e y easy. However e vasth ,t majority of these putative mutants were rejected. About 20% of the mutants selected were entered into yield trials in the 6 years of this study d mos an f ,theso t e were culled afte e yearon r . e experimentTh s specifically reported herein sViowed thae th t response was variable for the various agronomic traits among the mutants compared to their normal progenitors or isotypes. Whereas e mutantth som f o es appeare e improveb o t dr severa fo d l agronomic traits such as lodging resistance, yield, harvest index and earliness, none e desirablcombinth l al e e traits necessara r fo y new improved cultivar. Since sodium azide is a potent mutagen in barley d mosan , t mutation e deleteriousar s t surprisinno s i t i , g that some deleterious mutations simultaneously occur in most mutants selected for a desirable improvement. Also the background genotyp a give f o en induce e suitablb t dno mutaney ma r to geny ma e e optimutth o m expressio e mutanth f o tn trait. Severae mutantth f n o lthii s s study shoul e goob d d germplasm source n cross-breedingi s n Morei s relativell ha x Mo . y good yield potentia d gooan l d lodging resistance t poobu , r kernel characteristics and extreme lateness. If the desirable traits can be transferred without the undesirable traits improved progeny will s gooresultha d 4 straMo .d kerne an w l characteristicst ,bu poor yield potential e LarkeTh . r s mutangooha d2 L tyiel d potential, long coleoptile lengt d earlinessan h t poo,bu r straw. The allelic Advance mutant Al has better lodging resistance, but shorter coleoptile lengt d poorean h r kernel characteristics. Difference n backgrouni s d genotyp e seeb n thes i n o ca etw e allelic semi-dwarfs. e abovTh e mentioned semi-dwarf mutants coul e goob d d germplasm source r improvinfo s g barley, especiall n regari y o lodgint d g resistance or earliness. These mutants could be used in a pedigree

142 program, as they are all malting types, or they could be used in r existino w ne g male sterile facilitated recurrent selection (MSFRS) populations. The Advance, Morex and WA9044-75 mutants have already been used in crosses in our pedigree program and in MSFRS populations particularly modification f CCXXXIo s I (6). Also, selections have been made from this study's genetic analysis backcross and intercross progeny for channelling into our pedigree program. In any event the goal should be to find the optimum genetic backgroun r eacfo dh potentially valuable semi-dwarf gene and to overcome any deleterious mutations in the various induced mutants. Little detail has been provided here concerning the genetic analysis of the various semi-dwarf mutants. There have been some special problems encountered in interpreting culm length results when different genetic background e combinedar s e b . o t Thi s i s expected especially with a quantitative trait such as culm length. Ideally isogenic series would be developed for a set of mutants e analyzedtb o e havW . e trie o overcomt d e probleth e f differino m g genetic background y comparinb s g progeny with parents d wheran , e different, normal progenitor genotypes all planted in the same way n closi d e an proximit o eact y h other. Additional genetic work remains to be done with these mutants, such as isogenic line development, as well as continued allele testing among these mutants and other older and newer known sources of dwarfing genes (1, 15, 16). Chromosome location of new genes could also be done. To conclude on a positive note, the WSU barley breeding program has released a new semi-dwarf winter feed barley called 'Showin' (2905-75 jîhorr )fo t winter barley. Showi s resultenha d from mutatio d pedigrean n e breeding efforts e pedigreTh . f o e Shown includes the semi-dwarf 'Jotun' mutant and WSU's 'Luther' (an X-ray induced semi-dwarf mutant from 'Alpine'). Agronomic data from Showi s previouslha n y been reported (10, 11) .n additioI o t n short straw and lodging resistance, averaged over 68 location e tim yearth f releaso e t a s e (1985) d yieldeha 8 t ,i 11 d and 110% of 'Kamiak' and 'Boyer1, respectively, the leading commercial winter barley cultivar Washingtonn i s s anticipatei t I . d that succes n breedini s g semi-dwarf, lodging resistant barley cultivars will continue with the use of newer induced semi-dwarf mutants.

ACKNOWLEDGMENTS The authors wish to thank Alan Hodgdon for mutagen treatments, Carl Muir fielfo r d assistance, J0rgen Larse d Johan n n Ingversef o n Carlsberg Plant Breeding, Copenhagen for reviewing the manuscript, and e Departmenth f Physiologo t e Carlsberth f o y g Laboratory, Copenhagen for assistance in preparing the manuscript, especially Professor Diter n Wettsteinvo , Head d Hannan , e Them Nielse d Lisan n e Trillot, typists.

143 REFERENCES

) KONZAK(1 , C.F., KLEINHOFS ULLRICH, ,A. , S.E., "induced mutations in seed-propogated crops", Plant Breeding Reviews, Vol. 2 . (JANICK, J., Ed.) The AVI Publ. Co., Westport CT (1984) 13. (2) MICKE, 4., MALUSZYNSKI, M., DONINI, B., Plant cultivars derived from mutation induction or the use of induced mutants in cross- breeding, Mutation Breeding Review No.3, FAO/IAEA, Vienna (1985) 1. ) BACALTCHUK(3 , ULLRICHB. , , S.E., Stand establishment characteristics of barley genotype f differeno s t plant heights, Crop Sei3 2 . (1983) 64. (4) NILAN, R.A., MUIR, C.E., Registration of Luther barley, Crop Sci.7^ (1967) 278. (5) PERSSON, G., HAGBERG, A., Induced variation in a quantitative character in barley. Morphology and cytogenetics of erectoides mutants, Hereditas 6l_ (1969) 115. (6) RAMAGE, R.T., THOMPSON, R.K., ESLICK, R.F., Release of Composite Cross XXXII, Barley Newslette (19769 rJ_ . )9 ) RASMUSSON(7 , D.C., BANTARRI, E.E., LAMBERT, J.W., Registratiof o n 2 semi-dwarM2 d M2an 1 f barley gerra plasm, Crop Sei. J_3_ (1973) 777. ) -VETTSTEIN(8 von. D , , NILAN, R.A .AHRENST-LARSEN, ERDAL, . B ,, ,K. INGVERSEN, J., JENDE-STRID, B., KRISTIANSEN, K.N., LARSEN, J., OUTTRUP, H., ULLRICH, S.E., Proanthocyanidin-free barley: Progress in breedin r higfo gh yiel d researcan d h too n polyphenoi l l chemistry, MBAA Tech. Quart. _22_ (1985) 41. (9) ULLRICH, S.E., NILAN, R.A., BACALTCHUK, B., "Evaluation and genetic analysi f semi-dwaro s f mutant f barley"o s , Semi-Dwarf Cereal Mutants an dn Cross-Breeding I thei e Us r , IAEA-TECUOC-268, Vienna (1981. )73 (10) IILLRICH, S.E., MUIR, C.E., "Progress in the evaluation, use in breeding d genetian , c analysi f semi-dwaro s f mutant f barleyo s " Semi-Dwarf Cereal Mutants and their Use in Cross-Breeding II, IAEA-TECDOC-307, Vienna (1984. )31 (11) ULLRICH, S.E., "Progres mutation i s n breedin r semi-dwarfo g m fis in barley", Report for Third RCM on Evaluation of Semi-Dwarf Cereal Mutants for Cross-Breeding, Obregon and Mexico City, IAEA, Vienna (1984) Unpublished. (12) AYDIN, A., Agronomic and Genetic Characterization of Induced Semi-dwarf Mutants in Spring Barley (Hordeum Vulgäre L.), M.S. Thesis, Washington State University, Pullman (1985). (13) MYHILL, R.R., KONZAK, C.F., A new technique for culturing and measuring barley seedlings, Crop. Sei. 1_ (1967) 275. (14) RAMAGE, R.T., Comment malf o ee s sterilus abou e th t e facilitated recurrent selection, Barley Newsletter _2_4_ (1981. )52 (15) SZAREJKO , MALUSZYNSKIw dwarI. , ne genem fo is n barleTw o s , ,M. y chromosom , Barle3 e y Genetics Newslette 4 (19841 r . )35 (16) NILAN, R.A., The Cytology and Genetics of Barley, Monographic Supplement No.3, Research Studies, Washington State Univ. Press, Pullman (1964).

144 SELECTION OF COLD TOLERANT MUTANT LINES IN NAKED BARLEY (Hordeum vulgäre L.)

J.L. WON, G.H. CHUNG College of Natural Sciences, Gyeongsang National University, Jinju, Gyeongnam, Republi f Koreco a

Abstract

In orde o screet r e colth nd tolerant mutant line n nakei s d barley, seeds of recommended variety Baekdong were treated with x rays of 25 kR. Two cold tolerant mutant lines were selected under field conditions with the lowest winter temperature being from -13°C to -20° C, during ^ to M5 generations. The number of vascular bundles of cold tolerant mutant line BM- 5 was decreased and culm diameter was thicker than that of the parent line. Important characters of cold tolerant mutant line BM 5 were simila e paren o thosth t r f o et line.

1• Introduction

Induced mutations can be used to generate useful variation in inherited character d sucan s h mutant n w providca sourcne s f a o e germplas r improvemenfo m f o different t traits e maiTh n. advantagf o e mutation for plant breeding is the increase of the genetic variability within a relatively short period, including genetically controlled traits not existing in the non-mutated material. Mutagenesis has become a unique method for breeding in cases where the range of genetic variability in existing populatio s limitedi n . e mutanUnti th w mos no f lto t lines from various crops were selected for visible characters such as short plant height, early flowering and maturing, flower shape and size or seed and fruit size. Since mutants have expressed various adaptabilito t y environmental conditions, as compared to their parent lines, the possibility of selection for certain physiological characters important r crofo p plant s increaseha s d (Gregory, 1965; Konzak, 1959; Lapins, 1965; Mastenbroek, 1956; Mick t al.e e , 1985; Toriyam Futsuharad an a , 1960).

Cold tolerance in barley is one such important character for productivity and stable cultivation. Particularly, though naked barley in Korea has high yield, its cultivation area is limited to the southern part of the country because of susceptibility to cold (Fig. 1). There are no available germline r improvemenfo s f nakeo t d barle n thii y s charactern I . such case, induced n actuamutationa a uniqu d e b an l e y breedinma s g method r nakefo d barley e havW . e selected, under field conditions, useful cold tolerant mutant line n nakei s d barley after treatment with radiation. This paper reports on selection procedure and important characters of cold tolerant lines.

145 -38e

Seoul

-37"

-36C Critical boundary

35°

-34"

-33C

Fig. 1. Critical northern boundary for linked Larley in ?'.oroan peninsula.

2. Material and Method Recommended variety Baekdong of naked winter barley was used as material for treatment of matured seeds with 25 kR of x-ray in the Korean Atomic Energy Research Institute. Harvest of H-^ generation followed the mutation breeding method recommende r cerealsfo d . Cold tolerant lines were screened under field conditions using routine cultivation methods (Tabl . ) Investigatio1 e e numbeth f f vasculao o rn r bundle d culan s m thickness wer ed comparee parenan carrieth t o t ou d varietye Th . evaluation of such important characters as length of culm, nodes, spikes, numbe f nodeso r , numbe f graino r r spik d pe 1,00s an e 0 seeds weighs wa t conducte 0 plants2 n o d .

3. Results and Discussions About 5,000 grains were irradiated with a dose of 25 kR, which is recommended for mutation breeding in cereals such as barley and rice. Fou r0 grain 1 ^ plan spikeM r d spikr pe an stpe se were harveste n buli d k for M2 planting. About 100,000 plants in M2 population were grown for screening of cold tolerant mutant lines. The experimental farm where this screening was done for M2 - M5 generation is located in a region excluded for cultivation of existing naked barley varieties due to low winter temperature. Surviving plants in M2 population may include epigeneti s wela cs geneti a l c variants becaus f environmentao e l factors.

146 Tabl . 1 eSelectio n proces f colo s d tolerant mutant line from naked winter barley variety Baekdong

Winter temp f seedo , . sNo Generation Year (at lowest harvester o d Remarks selected lines

1976 Radiation treatment 1976/77 ca. 100,000 seeds

M2 1977/78 -15.0 ca. 500 plants Selectio* * n M3 1978/79 - 13.0 0 line3 sca. Selection ** «4 1979/80 18.5 5 lines Selection ** M5 1980/81 -20.0 2 lines (Mutant line BM-5 and BM-11) 1981/82 Seed multiplication, field evaluation Mj to present and basic study

* Plante Gyeongsann i d g National University * * Screene experimentan i d l far f Koreao m n Atomic Energy Research Institute, Seoul

e grainTh s from screene £ plantM d s were d singlan w planteß ro M e n i d s possibliwa t o confirt e m whether survivin 2 plantM g s were genetically changed. Amon e colth gd tolerant mutants selecte j therK n i ed existed mutant lines with negative characters. Such lines were eliminated from the experiment n succeedini s g generations o mutanTw . t lines BM-d 5an BM-11 were selecte $ generatioM n i d n (Tabl . Mutan1) e t BM- s bettewa 5 r than BM-11 froe poin th mf agronomio t c characters. Mutant line BM-s ha 5 similar characters to its parent variety, contrary to cold tolerant mutant BM-11 with short and stiff straw, smaller grain size, less number of grains per compact spike and higher susceptibility to fungi.

Histological observation has been made using culms of mutant and control line (Table 2). Culm diameter of mutant lines was thicker than the parent variety but the number of vascular bundles decreased in mutant BM-5. It is not known whether there is any relation between cold tolerance and culm thickness or number of vascular bundles. BM-5 mutant line has a similarity to the mother line in all important agronomic traits and differs only, besides cold tolerance s slightlit n i , y dark green leaves (Tabl . Yiel3) e d trial r officiafo s l n releasprogresi e ar n ei s different regions. Until now its grain productivity has been successfully evaluated. Furthermore, it would be interesting to investigate the genetic backgroun d physiologicaan d l characteristic e resistancth f o s o t e cold temperature. Crossing programme between the mutant BM-5 and the parent line or with other mutants will be initiated in the future.

147 Tabl . 2 eNumbe f vasculao r r bundle d culan sm thicknes f pareno s t variet d mutanan y t BM-5

No. of vascular bundles Culm diameter * (mm)

Mother variety 32.4 4.20 Mutan 5 - BM t 24.6 4.70

d internod2n * e from spike

Tabl . 3 e Important character f nakeo s d barley parent variety Baekdong and its cold tolerant mutant BM-5

Culm No. Spike Grains 1000 Response length of I* II III IV V VI length per seed to (cm) nodes ______(cm)_Spike weight(g) fungi

Baekdong mother 69.7 5 24.3 16.3 12.2 8.4 6.3 2.2 6.4 67.3 31.8 suscept- variety ible

Mutant 70.0 5 1 24.65.6. 6 36 2. 16. 31. 5 596. 11.toler 5 8. 7- BM-5 ant

* Spike internode

REFERENCES

GREGORY, W.C., 1964, Mutation frequency, magnitude f changth o e d an e probability of improvement in adaptation, The use of induced mutation plann i s t breeding, FAO/IAEA meeting, Rome. KONZAK, C.F., 1959, Radiation induced mutations for stem rust resistance in oats. 8 ,51 : Agron51 . J . LAPINS, K., 1965, Compact mutants of apple induced by ionizing radiation, Can. J. PI. Sei. 4_5:117. MASTENBROEK , 1956C. , , Some experience n breedini s g frost-tolerant potatoes, Euphytica 5_:289. MICKE, A., MALUSZYNSKI, M., DONINI, B., 1985, Mutation Breeding Review , IAEA3 . , No Vienna. TORIYAMA, K., FUTSUHARA, Y., 1960, Studies on the genetics and selection of cold tolerance in rice 1. Genetical analysis of cold tolerance, Japan . BreedJ . . 10:143.

148 GENETIC ANALYSIS OF INDUCED SEMI-DWARF MUTANTS IN RICE

. YAMAGATAH . TANISAKAT , , M. TOMITA, K. SHIRAISHI Facult f Agricultureyo , Kyoto University, Kyoto, Japan

Abstract A number of semi-dwarf mutants of rice were evaluated for 15 agronomic characters laying stress on plant type and grain yield, and some of them were genetically analyzegenee th sr controllinfo d e semith g - dwarf ness. 1) Principal component analysis for 14 characters revealed that various plant types of semi-dwarf mutants could easily be induced by mutagenic treatment, and the pattern of induced plant type was largely affecte e genotyp th e origina th y b df o e l variety. Graine yielth f o d induced mutants e tendemutante higheb th o n t di r s with larger "general size" irrespective of the original variety, but did not show particular relationshi e culth mo t ptrai s representea t y botb d h internode elongation and culm thickness. 2) Five of the nine induced semi-dwarf mutants analyzed were each provee controlleb o t d y singlb d e semi-dwarfing gene, and these mutated genes were considered to be non-allelic to each other. Among the remaining four, one carried two semi-dwarfing genes and three were broughe mutationth y b t n minoi s r gene system e dbo\ ) Baseth 3 .on o d results e higth ,h possibilit s indicatewa y r creatini-dwarfinm fo dse w ne g g gene resource r breeding fo se necessit th d i appros pointe,an fo wa y t -ou d priate choice of materials to be adopted and analysis of both induced and existing semi-dwarfing genes.

1. INTRODUCTION

s widelIi t y known thae appearancth t f semi-dwaro e f varieties ha s brough a tremarkabl y elevate d stabilizean d d productivit f rico y e cron i p Japan as well as in many other countries. According to some recent reports, however, the existing semi-dwarfing gene resource base is quite smaller than expected [1,2]. Such a situation is far from the idea that e genetith c diversity shoul e maintainedb d d suggestan , s that exploiting of new useful semi-dwarfing genes is of urgent necessity. Breeding by induced mutations has already succeeded in producing a number of excellent varieties and strains over various crops, and much has been expected from mutation breeding for further creating of new gene resources [3]. However, there are as yet few reports where induced semi- dwarfness was genetically analyzed together with the agronomic characteristics related to the semi-dwarfness. In this paper ) variou(1 , s semi-dwarf mutant f rico s e were evaluated for 15 agronomic characters and their mutual relationships, laying stress n plano t typ d graie genean eth ns) yield(2 responsibl d an , r semifo e - dwarfness were analyzed with 9 induced semi-dwarf mutants.

149 2. MATERIAL METHODD AN S S

2. 1. Agronomic characteristics of semi-dwarf mutants

a larg Ouf o te numbe f mutano r t stocks which were induced wit- f h NMUr rayso Al ,E fro varieties3 m , Gimbozu, Nihonmasand Noran m8 ,a 9 totasemi-dwar6 f o l f mutants, viz., 3 fro2 m Gimbozu 3 fro(Grou2 m, pG) 3 froNor2 md (Grou8 m an Nihonmasar ) M p i (Grou wer, N) pe selectee th n o d e paniclbasith f o se weigh d seean td fertilit t inferiono y o originat r l variety. These groups G, M and N are here each referred to as mutant 3 originagroup e Th . l varieties were include n respectivi d e groups. In addition, a total of 39 diverse types of varieties and induced mutants were also used as Group V for comparison with the mutant groups ; 6 semi-dwarf mutants (Hokuriku 100, Kantö 79, Reimei, Fukei 71, W 12 and W 24), 3 their original varieties (Koshihikari, Fujiminon and Wakaba) and 0 chec3 k varieties comprisin 0 semi-dwar2 g tal0 1 ld onesan f . Seeding and transplanting were made on 6th of May and 30th of June in 1982, respectively. Fertilizers applied were 6, 9 and 9 kg/10a for N, P2Û d 1^05an , respectively. cm d plan 0 an ,3 tx spacin0 1 s wa g Ten plants per variety or mutant were measured for 15 characters ; culm length (CL), panicle length (PL), panicle number (PN), numbe f elongateo r d internodes (EIN), first to fifth internode lengths (IN1-IN5), first to fifth internode diameters (IT1-IT5) and grain yield per plant (GY). Principal component analysis was applied to all the 14 characters other than gram yield to obtain an integrated figure of plant type and to discuss the relationship of plant type to grain yield.

Gen. 2 . e2 analysi f semi-dwaro s f mutants

Out of the above described Groups G, M and V, 3, 4 and 2 semi-dwarf mutants were respectively selected (TABL withou) H E t particular choice other than semi-dwarfness. They were crossed with their respective original varietie d analyzean s r semi-dwarfinfo do F d an o F ge th gen n i e generations. In each cross combination, about 300 F 2 plants and about 50 Fo lines which were raised from randomly selected ?2 plants, were subjecte analysise th o t d . These materials were grow n paddi n y field together with the cross parents and measured for culm length and heading date.

3. RESULTS AND DISCUSSION

3.1. Agronomic characteristics of semi-dwarf mutants

TABLE I indicates the first and second component vectors (zj and 2,^, respectively) extracted from the principal component analysis. As shown in this table, the cumulative contribution of Zi and z-> exceeded 70 percen n eaci t h group, suggesting thae totath t l multivariate variancf o e plant type could safel e explaineb y y thesb do e components tw eth l al n I . groups i gavZ , e positive loadinl organsal o t g. This means thai Z t indicate e isometrith s c phas f variatioo e n "generai n l size", wherl al e organs var n sizi y e almost proportionally e otheth n rO .hand ^ T. , seemingly indicates the allometric phase of variation between "upper- internode elongation with thick culm" and "lower-internode elongation with slender 3 culmgroup r "fo s other than Grou whil, N p e only between "upper- internode elongation d "lower-internodan " e elongation r Groufo " . N p Figure 1 gives the scatter diagram of plant type for all the varieties and mutants used in this experiment, according to the scores

150 Pooled : Grou • ) ( V p ( O: Grou ) G p ( A: Grou ) M p (d : Group N) M101 6 »Fukei 71 *• M9

• • •Millyan3 2 g

4 • • DGWG IR8* A a» • Yus*in . Taichung r-i° • Nativ1 e Re ime i 2 A • k D n *• • HokurikulOO Kanto79*Q O Nihorunasari 4 « CD A D / Shiranui r& * 0 > i i A A. r\ O ilTlTi 1 Û ^ D. 8OAfocoScrt ^Vjukkoku *G \ * • • A*O O 4* »»^eih\ o• -2 ' GimbSzu A , NOrin 8

( 2 - 4 - 6 - ) 2 4 6 8 Zl £>core FIG. 1 Scatte. r diagra8 varietie10 f o m mutant d an s s accordin e scoreth o t sge firs giveth d secon an ty b n d component vectors extracted from PCA for 14 characters.

obtained s clearlA fro(TABL^ i. m. yI) Ed poole an see i z nd from this figure e variatioth , f plano n r largetfa typn s Groui re wa e th V ptha n i n others, where the distribution of mutants was confined to a relatively small extent. 3 mutanAmon e th gt groups, Groud an M pG eac h showed larger variation than Group N, and the majority of the mutants were characterized by "lower-internode elongation with slender culm". The variatio f Grous almoso n wa N p t limitee smalth o lt d area confine^ z y b d below zero and T,^ near zero, and did not show such a trend of culm trait as observed in Groups G and M. Figure 2 shows the scatter diagram of plant type for the varieties and mutant n eaci s h grou. zn p d accordinan e score^ th z o f t o sg In Group V, 4 varieties possessing Jukkoku semi-dwarfing gene (Jukkoku, Shiranui, Hoyoku and Reihö ; Jukkoku-type varieties), 6 varieties possessing Dee-geo-woo-gen (DGWG) semi-dwarfing gene (DGWG, Taichung Native 1, IR 8, Tong-il, Yushin and Mdllyang 23 ; DGWG-type varieties 2 varietie d )an s possessing sd-, ; SD-typ gen1 10 e eM (M- d 9an varieties) bore close resemblance in plant type, respectively : Jukkoku- type varieties, characterized by "lower-internode elongation with slender culm" were situated far from the other two, which were conversely characterized by "upper-internode elongation with thick culm". From this e facanth dt thae abovth t 3 semi-dwarfine g genes have recently proved to be identical with or isoallelic to one another, It is suggested that e semi-dwarfinth g gene act t onl n sno culo y m lengt t als bu n hculo m trait as evaluated by length and thickness of internodes, but its action is strikingly influence e genetith y b dc background whic e genth h e belong. to s

151 O'-iOOCOOO^'d'CO-a'ChOUDCO en CM or~~cnincnr~-or-O'-it~-m.r-iro r NI (N'-iOrooj^HrorocM^'r )^''^'ro en t) 1 1 1 1 1 1 Q) I I rH O o cN'XirO'-icri^'oocOvHLno^rr^rsi CM dl »— t r^<3iœco^r

•^•^ocNimco^'-icocN'-icNLnocn CN omcnor'-r^iDr^r^'S'rNrorvir^ w NI OfintNmiHCN'-Hr'ifNr-i.-i»-!.-! 2 yD elongate c t o fift h

0, l i l l l l i i H-l 4J 3 O W O >-l M mrNimr^-rHCO'3'r--i£i«=}'v£>cncn--i en yt -H O »-H U)(T\nii)cM(Dr>jnuioinî'vrvD 0) DL, NI oor^coœcorôooor^-œcococor-- r- ANALYS ] -9 " VD E in 3 EH 2 M 1 2 -i H H T~HM3v£iT-(roromco<—ir^CNroo^ —* r^ W M r\i oocNî'CN'-ir— O'î'r^-^'ror^r^n S NI OO— imrsjrnO'q'rncNJcNmnLn en IOMPONEN T X "1 ft III i l l i •p x; 3 CP -P 0 C Cr> M oir-T-iilouiirirn-

S | 0 criLOLD'~ cri(^>^ûcriojroG^n(^T-* en oa (N ooLn

Cn e/ NI m--i— incNjnororM—irxiroroc N U3 3 L : Panicl e .nternod e I I II 1 a 1 1 1 s - X M 4-1 o x 1 M o3cr>( J'^r<"ocoö^Of"v ~)(T>^DLnt-Qit n o 0) 4-1 O •rH ovDO— iocN>-ir itNCTi'a'n'3 in £3 'H [SI coc~-cococor-CDcocor-cococor^ in B 4-1

"RACTE D >£> X W

00 05 O t^c^ocM'—i^fCTiro^i^r^cocNror^ - r~ (TioJ--|OCNOr~-cO'^-'=TOCM»-ir~ EH C\l 1 1 »-H

CN]cNcN^j ro^-<'-H^rro^ '^'î'-^'CM 3 U > NI Firs t o W anicl e n i 1 1 1 1 1 > a I I ) U > LT • • a 2 2 *-i H 0 &i M D 2 t-i ^- 4- ; ) U l -- ~ W o T-H LOCNLOLD^T*— tmr-ooo»xiÔkDoo 2 NI œcocor^r~-cocorôor^cococoi^- Vu x; 2 6

2'-H(^sJf>^^rLn'~'CNr^'^rL^ J2Jn22222HHtHEHtH

U&<(XWMHMMMMMMMM (% ) internodes , ] internod e di * CL : Cul m leng t Contributio n Character * TABL E I . COMP C

152 Group V Group M ' 0 (• : Jukkoku variety) Nörln 8) 0 (A:DGWG variety) <• ' O _ (• SD variety) Höyoku • : oo' pD (©:Mutant variety 0 and strain) (O -Others) 7 -* O O ^ Jukkoku i O • 0 rv U Shiranui* o o 6* 00 8 o ,———————— — o__ , , , , - , .. - ——— — 1 ,1— — 0—— 11—— —— — J —— o o n © ™ o N • Kant© 9 7 o . o Q Hokur 0 i k10 u ADGWG -2 ® Reime i AYushin 0 A Taichung- * NativA 1 e Tong-i8 IR l -4 ., O

— 6 0 0 • o ^Fukei 71 Mlol"

Group G Group N

4 ° . Gimbözu • ( ) ( • : Nihonmasan)

. o -

2-0 0 0 o 1 0 00 o o 0 0 _ ° 9> i ——— — t — i ——f — 0 — —— ' Ct O t 1 1 i IIl * -pt f\t* 0 — $-@K>— 0 ——— ° 0 0^0 O 00 o o • o o — 2 ^ 0 0 o

____x_ _ _ _ .»_____«______. -4-202 4 -4-202 Z, score

FIG. 2 Scatte. r diagra f varietieo m s and/or mutant n eaci s h group accordin e scoreth o t sge firs giveth d secon an y tb n d component vectors extracte characters4 1 r dfo froA PC m.

153 Four variety or promising mutant strains induced with f-rays (Reimei, Fukei 71, Hokuriku 100 and Kantö 79) exhibited the plant types conspicu- ously different fro mabove thosth ef o ethre e type f varietieso s 3 e Th . mutant strains as well as the variety, Reimei, have intensively been used s excellena t cross parent n breedini s r semi-dwarfnessfo g . However, taking account of the fact that Reimei, an induced mutant, and Jukkoku possess an identical semi-dwarfing gene [1, 4, 5] in spite of a great differenc f planeo t type betwees considerei t e twoi th n, d that promising mutants appearing hencefort s wela h s thesa l e mutamt strains shoule b d analyzed for the genes controlling the semi-dwarfness prior to the entry w genne es a sources. In Group G, the distribution of -z^ scores of the mutants had a strong bia n positivi s e direction agains e originath t l variety Gimbozu. This indicates thae semi-dwarth t f mutants induced from Gimbozu mostly manifest the plant type characterized by "upper-internode elongation with thick culm" compared with the original variety (TABLE I). In Grou , therM p s observewa e a strond g ^ score7 bia f n o negativsi s e direction but substantially similar to that in Group G, indicating that the same tren f plano d t typ s observea e n Grous trui di e eG p th als f o mutants induced from Norin 8 (TABLE I). An observable difference of Group M from Group G was that mutants exceeding the original variety in "general size" could not be found in the latter. s recognizeIwa n t Grou i a distinguishin , s N pa d g feature that most of the mutants came together near the z^ of the original variety, and thus did not show such a trend of "upper-internode elongation with thick culm" compared witoriginae th h l variet s observea y . M ThiGroupn i d ds an sG may be due to that the original variety, Nihonmasari, itself is a semi- dwarf variet f "upper-internodo y e elongation with thick culm". (Fig1) .

e relationshipTh o scoreZ f graio s d e depictean ar sn i yielZ n o i dt d , respectively4 d Figsan 3 . n GrouI ., highe V p r yields were observen i d the varieties with the scores of z-. above zero (Fig. 3) and ï^ below zero (Fig. 4), which were all indica or indica-type varieties (Fig. 2), indicating that the varieties of "large general size" and "upper-internode elongation with thick culm" tende o givt d e higher grain yield n GroupI . s e relationshith , N d an M p betwee, G n grai n^ scor z yiels substand wa ean d - tially simila o tha t rGroun i t , namelyV p , higher yielding mutants tended to show "larger general size". Between yield and ^2 score, however, no particular relationshi s observedwa p , except that some mutants with larger w Zmutantofe scora d n Grousi e an havin G p ^ scorï g e distant from thaf o t e originath l variet n Groui y N pgav e remarkably reducedy yieldan n I . case, it deserves attention that in Group N, some mutants showed better yield thae originath n l variety despit f equivaleno e o e scoreZ tth o t s latter. Som ] have7 reporte, 6 suggeste , [2 s d that "upper-internode elongation" type of rice is more favorable for productivity than "lower- internode elongation" type. In this sense, it appears somewhat curious tha eacn , som i M tf Group o hd e an mutant sG f "lower-internodo s e elongation with slender culm" type showed rather high yield, notwithstanding thes o grouptw e s were derived from "lower-internode elongation with slender culm" type varietie e e mainlth du e o sb . t y Thi (Fig1) y .ma s lower level of fertilizers applied in this study.

Thus e resultth , s derived froanalysie th m f principaso l components suggest that the agronomic characteristics of induced semi-dwarf mutants e strikinglar y affecte e genotyp th e origina th y b df o e l variety usedd an , tha n appropriata t e choic f materialo e e adopteb o t ss highl i d y significant for the successful induction of useful semi-dwarf mutants.

154 Grou V p : Nor Grou• ( ) m8 M p 4 0 G £ 2 0 Q o o o o o o °o o UÎ Q/J ç _ 0 00 o o° "«b o o o^>o - ^-2 0 °o o O o -4 0

0 5 0 4 0 3 C 2 0 1 0 2 5 1 0 1

: Gimbôzu Grou• ( G p ) 4 : Nihonmasan Grou• ( N p ) O O 0 O O • 2 O 0 0 0 ^? 0 o i T1 i_ i i o O "O o ——*o ~ ———o — —îT —' — — 0 00 ° 0? -2 0 0 0 c? o -4 oo

5 1 0 1 0 2 5 1 0 1 Yicid (g/plant)

FIG . 3 Relationshi. p betwee n, scor Z yiel d ean dextracte d from PCA for 14 characters in each group.

Group V Group M ( • : Norm 8) „ 0 4 ° 0 o 2 0^0 • 0) o o

: Gimbôzu Grou• ( G p ) : NihonmasanGrou • ( N p ) 4 O 0 0 0 2 O O 8 p 000° 0 Av JL ° o —5- oOô-oç^&y— 0 — g— — 0* o 00 -0 2 o o ° 0 -4 I 1 <] 1 1 1 1 1 1 1 10 15 10 15 Yield (g/plant)

FIG . 4 Relationshi. p betwee n- scor Z yiel d e an dextracte d from PCA for 14 characters in each group.

155 3. 2. Gene analysis

The mutants submitted to the analysis of semi-dwarfing gene and their original varietie presentee sar TABLn i d EH alon g with culm lengtd an h heading date e analysi e basiTh e gen.s th mad th f segregawa eo s n f o eso - tio n culi n m length, referrin e influencth o t g f headino e g tim n thio e s trait. The frequency distributions of culm length in Fo and the results of progen e summarizeyar ^ testF n Fig.n si i dd TABL 5an , EH respectively .

TABL . SEMI-DWAREÏÏ F MUTANTS ANALYSE D THEIDAN R ORIGINAL VARIETIES

Mutant or Culm Heading original Mutagen length date variety [cm]

HS90 Ï" -rays 50(64) 9.03 X82 y-rays 66(85) 9.06 IM222 dT-rays 72(92) 8.30 Gimbozu 78 9.01 M686 Ï" -ray s 61 (74) 9.03 M700 8" -ray s 69(84) 9.03 M803 r-rays 59(72) 9.03 M1007 f-rays 56(68) 9.02 Norm 8 82 9.01 W12 El 61 (81) 8.20 W12 El 63(84) 8.22 Wakaba 75 8.26

( ) . Percent of the original variety.

(1) HS 90 As seen from Fig. 5, the Fn following the cross between HS 90 and the original variety showed trimodal distribution of culm length, and allowed to infer that HS 90 has one semi-dwarfing gene which causes a remarkable reductio f culo n ms genotypilengtit d an h c valu n heterozygoui e s stats i e almost equivalen o tha t tf midparent o t . TABL J1lustrâteV EI 3 differens t type f frequenco s y distribution within line observe generation^ F- n i d , correspondin e typeg th thef parentao o st m 2 plantsF l s clearlA . y indicated by this table, all the 48 Fo lines could easily be classified into 3 groups corresponding to the 3 types of FT plants, and, as shown in TABLE HI, the segregation of Fo lines, viz., 10 [homo/ygous, tall] : 23 [heterozygous, intermediate] : 15 [homozygous, semi-dwarf], was quite well consistent with the expected ratio of 1 : 2 : 1. This result confirms the adequacy of the above consideration about the semi-dwarfing gene of HS 90.

156 TABLE ZU. CLASSIFICATION OF F3 LINES BASED ON THE TYPE OF CULM-LENGTH SEGREGATION

Segregation ratio for F3 lines Cross Genotype and phenotype of F2 parent Observed Expected

Dominant homo : tall 10 1 Gimbôzu x HS90 Hétér intermediat: o e 23 2 Recessive homo : semi-dwarf 15 1 (Tes one-genr fo t e segregatio ^=1.13: n , 0.50 0.750< 0

Dominant hom tal: o l 12 1 Gimbôzu x X82 Hetero : tall 26 2 Recessive homo : semi-dwarf 10 1 (Tes one-genr fo t e segregatio ^=0.50: n 900. 0 )< .75,P 0 0<

Dominant hom tal: o l 13 1 Gimbözu x IM222 Hetero : tall 24 2 Recessive hom semi-dwar: o f 13 1 (Test for one-gene segregation : 7^=0.08, 0.950< P< 0.975)

Dominant hom tal: o l 10 1 Nenn 8 x K686 Heter tal: o l 21 2 Recessive homo : semi-dwarf 19 1 (Tes one-genr fo t e segregatio 500. 0 2.76)< = .25 P 0 ^ , 0< : n

2 gene-dominant homo : tall 2 1 i gene -dominant homo, 1 gene neter: o tall 10 4 Norm 8 x M700 2 gene-hetero : tall 12 4 i gene-hetero, 1 gene-recessive homo : intermediate 15 4 1 gene -dominant 1 gene-recessive homo : intermediate 6 2 2 gene-recessive homo : semi-dwarf 5 1 (Test for two-gene segregation : ^=2.56, 0.750

Norm 8 x M803 Minor genes : semi-dwarf to tall (Continuous distribution)

Dominant hom tal: o l 11 1 Norm 8 x M1007 Heterc : tall 27 2 Recessive homo : semi-dwarf l i 1 1 (Test for one-gene segregation : -X=0.52, 0 . 750< P < 0 .900)

Waxaba x W12 Minor genes : semi-dwarf to tall (Continuous distribution*)

Hor.o hoir.ozygous, Heterc : Heterozygous, Hig. " h coricldtior s observe.wa d between culm lengt d headinan h g date. (a) G x HS90 (b) G x X82 (c) G x IM222 HS90 X82 IM222

u c & 20 i-0)l CM

(d) M x M686 (e) M x M700 (f) M x M803 M686 M700 M803 M M

(i) W x W 24 (g) M x M1007 (h) W x W12 M1007 W12 W24 M

0 10 0 8 0 6 0 4 40 60 80 100 40 60 80 100 Culm length (cm)

FIG. 5. Frequency distribution of culm length in 9 F^ populations. G : Variety Gimbozu Variet: M y Nöri8 n Variet: W y Wakaba

158 TABLE I/. FREQUENCY DISTRIBUTIONS OF CULM LENGTH IN SOME REPRESENTATIVE F3 LINES WHICH WERE DERIVED FROM THREE DIFFERENT TYPES OF F2 PLANTS ( Gimb5zu x HS90 )

Genotyp phenotypd an e f o e Culm length (cm) F2 parent 40 .... 50 .... 60 .... 70 ..•.80 • . • . • 0 .9

3 1 4 4 1 4 4 1 Dominant homozygou tal: s l 1 2 5 4 5 3 1 1

21200001112142 2 0 0 1 3 1 Heterozygous : intermediate 2002101100313400 0 2 1 0 1

1217741 Recessive homozygous : semi-dwarf 1524532 (2) X 82, IM 222, M 686 and M 1007 e frequencth o t s yA distribution f culo s m n populationF lengt 4 n i h s s somewhawa t i M 1007 t,d difficulan 6 68 o M fin t t tM 222 I ou ,d , wit82 X h any break points of the distribution and, in its turn, to estimate the segregation ratio (Fig. 5). In each of the 4 cross combinations, however, all the Fn lines could easily be classified into 3 groups as in the case observee th d an d , segregatio90 S oH f n ratio f [homozygouso s , tall: ] [heterozygous, tall] : [homozygous, semi-dwarf] were well fitted with the expected ratio in one-gene segregation, 1:2:1 (TABLE UZ). From this e culth rati md lengtan o f eaco h h e saib mutan dn ca tha tt i t(TABL , ) E EI th 4 mutante s analyze e semi-dwarfind on eacs ha h e degreg th gene f t o ebu , gene action to reduce culm length varies with mutants, being in the order M 222I . > 2 8 X > M 100 7= 6 68 oM f M 686 , d an however 2 Wit8 X h , ther s observewa e closa d e relationship between culm length and heading time as illustrated in Fig. 6, which depicts the case of Gimbozu x X 82. As seen from this figure, recessive- homozvgous genotyp r culfo em length apparently delayed heading time compared with dominant-homozygous and heterozygous genotypes. A similar tendency was observed also in the case of Norm 8 x M 686. This suggests that each of the semi-dwarfing genes of these 2 mutants is closely linked with some mutated late-headin a pleiotropi gs ha gen r o e c effecn o t delaying heading time.

90 X 82

G 0) 80 QGimbozu

70 .OO 6X 82 D1 C 0) 60 e ,—<

U •30 Aug . Sep. 25 30 4 9 Heading dato (F line mean)

. 6 RelationshiFIG. p between culm lengt headind an h e gcros th dat n si e of Gimbözu x X82.

(3) M 700 Regardin M 700g , ther s observewa e continuoua d s frequency distributio f culo n mt allo no » whiclengte discret p2 d th w di n hi h e grouping . o lineF However5) 0 (Fig5 s. e coulth , d comparatively with ease b e classified into 6 groups. The observed segregation ratio of 2 [2 gene homozygous, tall] : 10 [1 gene homozygous, 1 gene heterozygous, tall] : 12 [2 gene heterozygous, tall] : 15 [1 gene heterozygous, 1 gene homozygous, intermediate gen2 [ e6 homozygous: ] , intermediate gen2 [ e5 homo]: -

160 zygous, semi-dwarf] was quite well consistent with the ratio of 1 : 4 : 4 whic, 1 s expecte: i h 2 r two-gen: fo d4 : e segregation. From this segregatio ncule th ratie presumem b d lengtan o n M 700ca f t o dhi , tha t this mutansemi-dwarfin2 s ha t g genes with rather weak actio n reducino n g culm length.

4 2 W d an 3 80 M ) (4 In regard also to M 803 and W 24, the discrete grouping of F 2 plants was impossible, because of their continuous frequency distribution of culm length (Fig. 5). Furthermore, it was also impossible to classify the Fo lines, because their respective phenotypic variances took similar valuo t e eac e linh th othee d meanan r s formed nearl a normay l distribution curve, whica comparativel d ha h y wide variatio a pea d k an naroun e midparenth d t value. Such frequency distribution f culo s m lengt s observea h 2 F n i d Fo suggese th o t t 4 wer tha2 semi-dware e du eW th t d an 3 f80 nesse M f so mutations induce n respectivi d e minor gene systems e facTh .t thao n t transgressive segregants were observed may indicate that the mutations occurred unidirectionally.

2 1 W ) (5 With respect to W 12, the segregation behaviors in F 2 ar|d Fo were almost the same as observed in those with M 803 and W 24, indicating that minor gene mutation e responsiblar s e culth mr lengtfo e f thio h s mutant. s showA n Figi n , however.7 e culth , m lengt d headinan h g o linF tim f eo e were positively correlated with each othe o highls r y o thaF e t th mos f o t lines were distribute d closele lin an th f lineao e n o o dt y r regression. These facts suggest thae semi-dwarth t s broughwa 2 1 ft nes W abou f so y b t the mutations of minor genes which are responsible also for heading time. Both W 12 and W 24 are the mutants rated high in that they possess also early maturity and blast resistance which were induced coincidentally with the semi-dwarf ness. Therefore, the results from the above gene analysis may suggest tha semi-dwara t f ness induce minoy b d r gene mutatione sar worthy to be examined for its utility in certain cases.

cm 90

OJ W 12 Wakaba 6 S 80

Wakaba 70

c 111 W 12 60

3 U 50 Aug. 10 15 20 25 30 Heading dat F ( line e mean)

FIG . 7 Relationshi. p between culm lengtd an h heading date in the cross of Wakaba x Wl2.

161 As mentioned above, as many as 5 of the 9 semi-dwarf mutants analyzed here were yielded through the single gene mutations for culm length, and e semi-dwarfinth g genes detected were considere e non-allelib o t d o eact c h other. These facts indicate that various semi-dwarf mutants with different genotype r semi-dwarfnesfo s n comparativelsca y with ease b e induce y simplb d e genetic alteration, suggestin e higth g h possibilitr fo y creating new semi-dwarfing gene resources and the necessity for gene analysis with induced semi-dwarf mutants. On the other hand, the astonishing fact that most of the semi-dwarf varieties being widely cultivate n Japani d , south-east Asid Californian a a have same semi-dwarfing gene, sdj [4], urges to find out and exploit new substitutive semi-dwarfing genes. In this connection, Yamagata et al. [6] an d] detecte Tanisak[8 . al a usefudt e a l semi-dwarfing gene non-allelic to sdj in an experimental stock. Moreover, Tanisaka et al. (unpublished) have recently found that a Japanese super-variety Kinmaze has a useful semi-dwarfing gene non-alleli d sd^ an o sdj t c.n Lve,sd n only from these two e suggestefindingsb y ma t i d, that within close , therrangus e f ar eo e t unexploreye man s a y d useful semi-dwarfing genes other than sd^. Thus, s considereii t d thae analysith t f semi-dwarfino s g genes shoule b d advanced also for existing varieties.

. CONCLUSIO4 N

Through the analysis of principal component, it became clear that various plant types of semi-dwarf mutants could easily be induced by mutagenic treatment e pattere induceth th d f o nan ,d plant typs largelwa e y affected by the genotype of the original variety, so that an appropriate choice of the material to be used was highly significant for the successful induction of useful semi-dwarf mutants. From the analysis of semi-dwarfing genes, it was suggested that the semi-dwarfnes f induceso d mutant n mani ys wa cases s brough y singlb t e gene mutation d thae mutate,an th t d semi-dwarfing genes were non-allelio t c each other in not a few cases. These facts suggest that there exist a lot of loci concerning semi- dwarfness and an appropriate induction of mutations gives a high possibility to create new semi-dwarfing gene resources. In any case, it seems n immediata e b o t e subjec f importanco t o examint e e whethe e induceth r d semi-dwarf ing genes are useful for practical breeding or not. For this purpose, the effect of those genes on agronomic charae ters, especially on yield, should be analyzed. At the same time, the analysis of semi- dwarfing genes should be advanced also for existing varieties and mutants s wela s inducea l d ones.

REFERENCES

] KIKUCHI[1 IKEHASHI, ,F. NAKANE, ,H. YOKOO, ,A. , Japan,M. . .J Breed 1 Suppl.3 (1981, 1 . ) 138. ] YAMAGATA[2 , TANISAKAH. , , OKUMOTOT. , , N1SHIMURAY. , , IAEA-TECDOCM. , . 307 (1984) 149. [3] ______, Gamma Field Symposia 20 (1981) 11. ] [4 , RUTGERAdvanceN. . J , n i Agronoms 6 (19833 y ) 383. ] [5 IKEHASHI , KIKUCHIH. , , F. ,JAR1982 ( 5 Q1 ) 231. [6] MORISHIMA, H., OKA, H., Japan. J. Genet. 43 (1968) 181. ] OKA[7 , MORISHIMAH. , , JapanH. , . GenetJ . 3 (19684 . ) 191. [8] TANISAKA, T., SHIRAISHI, K., OKUMOTO, Y., YAMAGATA, H., Japan. J. Breed 4 Suppl3 . , (19842 . ) 348.

162 INVITED PAPERS TRANSFE ALIEF RO N GENES INTO CULTIVATED WHEA TRITICALD TAN E GENOTYPEE TH Y SB USE OF HOMOEOLOGOUS PAIRING MUTANTS*

C. CEOLONI Divisione Tecnologie Biologich Agranee , ENEA-FARE, CRE Casaccia, Rome, Italy

Abstract

Alien species, both wild and cultivated, can greatly help in broadening the genetic base of presently cultivated wheats, thanks to the large reservoir of useful genes they contain. However, introductio f substantiao n l portion f alieo s n genomes into cultivate- ge d notype mosn i s t cases makes them unfi r commerciafo t o t l e usedu , the contemporary presence of positive and negative traits carried by the alien material. Therefore, what appear e generallb o t s y needed o obtaiit s n transfers that includ e shortesth e t possible alien segment(s). Exchanges induced between functionally related (=homoeologous) chromosomes are the most likely to produce balanced and, thus, agronomically well performing transfer lines. Since mor r leso e s close homoeology has been proved to exist between each alien chromosome and certain wheat chromosomes, but, in spite of this, they are prevented from pairin d recombinan g e wheath y tb epairin g control system and mainly by the Phi gene, the use of phi mutants, available in common and durum wheat and, recently, also in a primary 6X triticale background, allow efficientlo t s y overcome suc n obstaclea h . Preliminary result e reportear s d wora her f ko e aime t transa d - ferring to common wheat a gene for resistance to powdery mildew derived from Tnticum longissimum a diploi, d species wit vera h y closely related genome to the B genome of polyploid wheats. As donor line a T.longissimum ditelosomic addition to Chinese Spring was used. The alien telo, bearin e resistancth g e gene(s), corresponde e shorth o tt d arm of chromosome G, whose homoeology with the group-3 chromosomes of common wheat had been established. A transfer scheme has been adopted that, within two generations of crosses, of which one with i mutanthph e f Chineso t e Spring, provided plants havin singln i g e dose alieth e n telocentric,its wheat homoeologue (alternativel, 3A y 3B or 3D) and a 5B/phl chromosome. Such plants were then pollinated by the standard euploid for the recovery of recombinant types. The frequency of recombinant résistant plants detected so far suggests thae pairinth t g frequency betwee e alieth ns whea nit - telho td an o moeologues was quite high, most probably ranging between 25 and 30%, on an average.

) Contributio(* n Divisione n°10th f 4o e Tecnologie Biologichd e e Agrarie - E.N.E.A.

165 Wite majoth h r objectiv f improvino e g triticale bread making quality, extensive use is also being made of the phi 6X triticale parente th e varioun i son s a s wide crosses with differen tD genom e sources, including common wheat and synthetic amphiploids. The remarkable increas n homoeologoui e s pairinl F e g th observe l al n i d plants, together wite fairlth h y successful obtammen C deriB f t-o vative o cultivatet s d triticales, allow good i confidencph e th n i e mediated recombinatio a promisin s a n g metho r triticalfo d e improvement .

Ir natur e regularitth e f meiosio y d thue successan s th s n i ,

evolutionary terms f alloo ,d alsan -o autopolyploid plant s beesha n

largely achieved throug a diploid-likh e behaviou f chromosomeso r , resulting in almost exclusive bivalent type of pairing at first me-

taphase. Polyploi d e moswheatth t e typicaar s d besan l t studied examples to this respect. In contrast to what happens, for istan- ce, in allopolyploid Festuca species (1), where the genes restric- ting pairing to homologous pairs appear to be ineffective in the hemizygous state, thus creating virtually no barrier to recombinatio f charactero n s between related species e typ th f ,pairino e g control existin n polyploii g d wheats e homoeoloth , o mostlt e -du y gous pairing suppressor gene Phi, is fully effective in the hemizygous state and, therefore, it represents a major obstacle to interspecific and intergeneric transfers between wheat and related Tri- ticinae.

The approach to resort to alien species as a method for the improvemen f cultivateo t d wheat s probablyi s t presenta , s it n i , transition phase from being a cytogenetic curiosity to being an increasingly urgent need for further achievements in wheat breeding. Indeed, the genetic material present in the world assort- men f cultivateo t d wheat varietie s beini s g exploite e fulth -o t d

lest. Besides this s rangit ,f variatio o e s rapidli n y decreasins a g e a enormouresulth f o t s selection pressure applie n thio d s cro- du p ring the last century. No doubt that the trends dictated by the "Green Revolutions" resulte outstandinn i d g successe severan i s l

166 cases. However, nowadays breeders are certainly facing a number of

newly arisen problems which appear to have limited and, sometimes,

not available solutions if only the cultivated gene pool and stn- ckly conventional breeding methodologies are used. As several ana-

lyses of population growth, economics of farming and energy needs in fact underline, n urgencthera s i ef furthe o y r raisin e ceith g -

ling to yield, both in quantity and quality, coupled with enhanced stability of output. This is true for several main crops, including

wheat. More than this, poor pest ménagement and poor toleranct ~>i r croou p varietie o mant s y different environmental constrains hav- e solvedb o t n thiI . s connectio e genetith n c approac s certainli h y e mosth t economica e leasth d t an damaginl e environmenth o t g t (2,3) Wild species can help a lot in enlarging the genetic variability of crop varieties; they not only contain resistance genes to several wheat diseases, but also represent a large reservoir of genes for getting wheats with high protein content, higher amoun f esseno t - tial aminoacids, improved drought resistance and salt tolerance; more than this e cytoplasmth , s wel a ss nuclea a l r gene f diffeo s - rent wild relative f wheao s t induce male sterility a trai, t which

may be profitably used for a "clean" production of hybrid wheat.

Complete homology may exist between the genomes of the alien and the cultivated species and, in this case, gene transfer can be

accomplishe y conventionab d l breeding techniques. However, with progressively decreasing cytogenetic affinity, alternative and more sophisticated approache se - followedb hav de o t l e al t , no mos f i t mandin constana g t referenc e chromosomth o t e e breee statuth -f o s ding material.

Introduction of substantial portions of alien genomes into cultivated genotypes ,synthetin i suc s a h c amphidiploid d alsan s o in additio d substitutioan n n lines mosn i , t cases makes them unfit

for commercial use, due to the contemporary presence of positive and negative traits carried by the alien material. Therefore, what

167 appears to be generally needed is to obtain transfers that include

the shortest possible alien segment(s).

r transferrinfo y wa e On g less tha n entira n e chromosomy b s i e

f ionizino e thus e g radiations e firsTh . t experimen f thio t s type

involved the transfer of an Aegilops urrbellulata chromosome segment,

bearing resistanc o wheat e t leaf rust o chromosomt , f wheao B 6 te e resultinth f o e (4)gOn line. s thewa s n use t Purdua d o develot e p the variety Riley 67, which has been recently utilized in Italy by

Dekal o bree t be variet th d y Chiarano, showin n outstandina g g per-

formanc severan i e l fiels trials this last year. Another successful radiation-induced transfer involved the translocation of an Agropy-

n elongaturo m chromosomal segment, carrying resistanc o stet e m

rust, to wheat chromosome 6A (5). This resistance has been incorpo-

rated into four Australian cultivars (Eagle, Kite, Jabir d Avoan u -

cet), which were reporte e y Driscol b dth o represen t f o ) % (6 l7 a t

Australian ^heat crop at the beginning of the SOties. However, in

w othespitfe a rf thes o enotabld an e e exceptions, generally radia-

tion-induced translocations suffer fro numbea m f limitationso r ,

inherent to the method in itself: breakages occur essentially at

random; interchange e mainlar s y terminal e majoritth ; f thee o y ar m

genetically unbalanced, as they involve non related chromosomes; their male transmissio s consequentli n y quite low.

Fortunately, it turns out that, with few exceptions, each alien chromosome has retained considerable relatedness with certain wheat chromosomes and is only prevented from pairing with them by the wheat pairing control system. Therefore, by altering the genetic environment, tha s operatini t o "relaxt o e s restrictiog th " o t n homologous pairing only, transfers can be obtained between functionally related (=homoeologous) chromosomes. This, of course, highly reduce e probabilitth s y tha deletiona t , thoug smala h l onea f o , wheat segment will result in negative effects, since homoeologues

are known to be able to largely compensate for each other from the

168 functional poin f viewo t . Wheat, especially common wheat para s i ,- ticularly amenable species for works of this kind. In fact, not only almost all the possible aneuploid lines for entire or telocentric chromosome e availablear s , e exceptionathankth o t s l worf o k Sears. ER . t als,bu o several additio d substitutioan n n linef o s single alien chromosomes or telosomes into the wheat background ha-

ve been produced, which give fundamental informations for the establishmen e feasibilitth f o t a transfe f o y r work. The facn i y t first of all allow to ascertain whether or not the alien gene expresses itself once introduced into the recipient genome, but also permit to quickly determin relationshipe th e f homoeologo s y existin- be g tween the alien chromosomes and their wheat counterparts. Once this is madeo creatt ,s i a e wha"pairin e o needd on t o t s g permissive" condition for the critical homoeologous partners. To this respect, t presena e war et more lucky than cytogeneticist f somo s e years ago. We do not have, in fact, to use a nullisomic condition for the entir B chromosom5 e e (wit s consequenceit h termn i s f aneuploido s y o induct etc.) e homoeologous recombination- lo i .Ph Mutante th t a s cus have been obtained in recent years in hexaploid wheat (7), iprimara alsd n n an durui o ) X tritical6 y(8 m backi e ph (9)-a n .I ground, added or substituted alien chromosomes can pair and exchan- e genetig c material with their wheat homoeologues, especiallf i y proper aneuploid line e use s recipienar a d d donoan t r parents which allow to create a chromosomal situation, in particular a monosomic condition for the crutial chromosomes, due to which they are already prone to pair. Experiments based on the use of phi mutation s pairina s g induction system havt beeno e n very numerouo s far. In all the reported cases, always an Agropyron chromosome (in 3 case. intermediumA elongatu. 1 A s n i d s use an ms )donowa a d f o r resistance to various diseases (10, 11, 12, 13).

Preliminary results are reported here of a work recently un- dertaken (14) with the aim of transferring to common wheat resistanc o wheat e t powdery mildew derived fro . longissimuT m . Ae = ( m

169 longissima) a diploi, d species wit vera h y closely related genome

genomB e tf polyploith oo e d wheats s donoA . r line . longissiT a , - mum ditelosomic addition to Chinese Spring, previously produced by the author(15) s used wa e alie, Th . n telosome, bearin e resistancth g e gene(s), corresponded to the short arm of chromosome G. The availa-

ble markers for this arm allowed to establish functional homoeology of chromosome G with the group-3 chromosomes of common wheat (15, 16). Base n theso d e observations ,transfea r schem s beeeha n adopted (Fig. 1) that, within two generations of crosses, one of which

with the phlb mutant of Chinese Spring, provided plants having in single dose alieth e n telocentric s wheait , t homoeologue (alterna- a SBph d lan chromosome) 3D r o B tivel3 ., Plant3A y s with- sucge a h

netic constitution were then pollinate e standarth y b d d euploir fo d the recover f recombinano y t types. Meiotic analyses, made rather difficult by chromosome clumping, indicated a 10% pairing frequency

between the alien telo and its wheat homoeologues, on an average (TabAccordin. I) .e observe th o t g d type d relativsan e frequencies

of the paired configurations involving the alien telo (heteromor- phic bivalent and telotrivalent, see tab. 1), a preferential pairing seems to exist between the telo and its closer wheat homoeolo-

gue, i.e. 3B. The frequency of recombinant résistant plants recovered so far suggests that the meiotic data represented an underesti- mate and that the actual pairing frequency most probably ranged be-

d 30%tweean .i conditio5 2 SincnPh n i e o sucn n h pairing occurs, the efficacy of the inductive system adopted appears remarkable. Meanwhile the size of the experiment is being enlarged, in order to widen the number and the spectrum of the resistant transfers, those already recovere e beindar g characterize r malfo e s a dtransmissio n of the recombinant chromosome, wheat chromosome involved in the transfer, fertility etc. n orde,i o select r e bestth te b one o t s

introduce s mildea d w resistant parent n conventionai s l breeding programs.

170 CS mono 3B- mono 5B T. longissimum G short

( 2n= 40 ) ditelo addition 42+2= 2n ) t ( sélection

19" + l'SB/Phl + l'3B + t'Gs CS phl/phl

( 2n= 40+t ) ( 2n=42 )

sélection

19" + l'5B/phl + l'3B + t'Gs

( 2n=40+t )

HOMOEOLOGOUS PAIRING I

X standard selfing euploid (CS)

plants with homoeologous pairing (5B'phi or 5B"phl/phl)

X standard euploid (CS)

SELECTIO F RECOMBINAN0 N T RESISTANT TYPES

Fig. 1 . Procedure followed to induce pairing between T. longissimum

chromosom shor G etelosom m s ar group-it t d an e 3 wheat homo-

. Chinescv eologue = S C e ( Sprins . ) g

171 Table 1. Metaphase I pairing of the T. ^'^Pjy^^A^jn short arm telosome in 2n=40+t plants having in monosomic condition

chromosome 5B/phl e alieth , n telo and n turn,i , eacf o h

its wheat homoeologues.

Group-3 N° N° % cells with telo paired wheat of of mono some plants cells Hetero- Telo- Total morphic trival. bivalent

3A 4 68. 142 8 2. 5.6

3B 3 173 2 1. 10.411. 6

3D 2 60 5.0 3.3 8.3

Anothef experimento t se r presentls i s y whicn i unde y hwa r extensive use is being made of a recently obtained phi primary he-

xaploid triticale (9). This triticale mutant, which was produced by colchicine treatment of the Fl between the phi durum wheat of the Italian cv. Cappelli and a rye inbred line, allows to approach the problem of reducing certain defects of the presently cultivated triticales through chromosome manipulation techniques- .ma Wite th h

jor objective of improving bread making quality, the effectiveness i mutatioph e th n inducini nf o g recombination betwee e chromosoth n - mef differeno s tD genom e source d thos an sf tritical o e beins i e g exploited. To this aim, various wide hybridization crosses have been performed e parentth s f alway o whicn wa s i , e on sh represented

by the phi 6X triticale arid the other, besides carrying a D genome,

either carrie i mutateph a dB chromosom 5 d r lackeo e e entirth d B e genome i homozygouph A . r hemizygouso s condition could - e thu e b s stablished for the occurrence of homoeologous recombination, most probably involvin genomD e th ge chromosome e parenon d thosf o an st e

172 of the A and B genomes of the phi tnticale line. At present, work is particularly concentrated on the following cross combinations. i triticalph commoi X 6 ph x en ) wheaa Chines. cv t e Spring. This represents the most direct way to introduce D genome chromosomal segments from the wheat parent into triticale. Obtainment of Fl seeds was relatively easy, but sterility problems are being encountered in selfed and BC generations to normal triticale.

ventricosa/S. Ae ) b . céréale amphidiploi i triticaleph X 6 x d ; Ae. ventricosa/T. boeoticum amphidiploid x 6X phi triticale. Crossabilit f boto y h these amphidiploids with triticald an e s fairlth wa f theieo s seeyt Fi r se goodd - EC' o cultivast - ted triticales are yielding seeds in considerable amount. Meiotic analyse triticale th f o s e wheax e th s (9) f Fi t o s wel ,a s a l hybrids involvin D genom e th ge carrying synthetic amphidiploids

(17, see also tab. 2) showed the appearance of multivalents, both

trivalent d highean s r rank configurations considerabln i , e amount

Table 2. Metaphase I pairing behaviour of Ae. ventricosa/S. céréale amphidiploids crosse i hexaploi y normaph b d d an l d triticale. Mean values and ranges (in brackets) are reported. 100 s wer ' C e PM score r hybripe d d combination (data partly frorr Ceolon al.t e i , 1986).

Hybrid % genomic Unival. Bival. Trival. Quadriv. Quinq. paired formula chrom .

32.42 4.74 0.02 0.01 - 22.8 (26-42) (0-8) (0-1) (0-1)

v M DAB(phl)R1R2 19.75 8.39 1.44 0.20 0.05 52.74 (10-31) (3-15) (0-4) (0-1) (0-1)

Frenca = e inbre ! ry hR ) n dinbrea (* lineobtainee = ry 2 dR ; d from P.B.I., Cambridge; R-j = a Hungarian rye variety.

173 when the Phi suppressor activity was absent. C-bandmg analysis of

the meiotic configurations of the phi triticale x phi common wheat hybrids above mentioned revealed that s expecteda , , homoeologous pairing mostl - genomD d y ean involve chromosome- B , A- d d onlan s y

rarely wheat and rye chromosomes (Jouve, pers. comm.). Although

this f courseo , , doet prevenno s t from reachin e purposth g f o e

transferrin genomD g e chromosomal segment o hexaploit s d triticale, it perhaps indicates that with very distantly related species from wheat, such as rye, the potency of the phi mutation might not be

sufficient to induce practically usable levels of recombinations.

e possibilitTh e s definitelstilb ha yo t l y ascertained whether i ceilinph r e homoeologoufo th g s pairin e furtheb y ma g r raisey b d

combinin witt i g h mutation r othefo s r suppressor r wito s h increased dose f pairino s g promoters. Alternatively, greater advantage e cas f th transfethao e n i n r induction between closely related spe-

f radiationse takeo b ciee n nus ca s froe th m, includin e polleth g n irradiation technique. "Genome restructuring" genes, such as the one recently discovere n Aegilopa n i d s longissima accession (18), may also prove useful to induce exchanges of genetic material be-

tween distant homoeologue r betweeo s n non-homologous chromosomen i s interspecifi d intergenerian c c hybrids. However, knowledg n thii e s

field has certainly to be increased before the best use can be made f theio r potentia r practicafo l l purposes.

REFERENCES (1) JAUHAR, P.P., Some aspects of cytogenetics of the Festuca-Lo- lium complex n "Cytogenetici , f croo s p plants" (M.S. SWAMINA- THAN, P.K.GUPTA and U. SINHA, Eds.(1983)309-350.

(2) SWAMINATHAN, M.S. and P.K. GUPTA, Improvement of crop plants- emerging possibilities, (see réf. 1)1-18. ) SIMMONDS,(3 N.W., Gene manipulatio d planan n t breeding, Proc. 16th Stadler Genetics Symp., Columbia, MO, 1984 (Ed. J.P. GUSTAFSON), Plenum Press (1984)637-654.

174 (4) SEARS, E.R., The transfer of leaf-rust resistance from Aegi- lops umbellulat wheato t a , Brookhaven Symp. Biol 9 .(1956 ) 1-22. ) KNOTT(5 , D.R. e inheritanc,Th f ruso e t resistancee Th . VI . transfer of stem rust resistance from Agropyron elongatum to common wheat ,. Sei CanPI 1 (1961 4 .. .J ) 109-123. (6) DRISCOLL, C.J., Perspectives in chromosome manipulations, Phil. Trans Soc. R . . 2 Lond(1981)535-54629 B . .

) SEARS(7 , E.R. n induceA , d mutant with homoeologous pairinn i g common wheat, Can. J. Genet. Cytol. 19 (1977) 585-593.

) GIORGI (8 homoeologouA , ,B. s pairing mutant isolate Tritin i d - cum durum cv. Cappelli, Mut. Breed. Newsl. 11(1978) 4-5.

(9) GIORGI, B. and C. CEOLONI, A phi hexaploid triticale production, cytogeneti cr intergeneri fo behaviou e us d an rc gene transfer, Proc. EUCARPIA Meeting on Genetics and breeding of Triticale, Clermont-Ferrand,France, July 1984 (1985)105-117.

(10) WANG, R.C., LIANG, G.Hd E.Gan .. HEINE, Effectivenes- ge h p f o s ne in inducing homoeologous chromosome pairing in Agrotricu-n, Theor. Appl. Genet 1 (19775 . ) 139-142.

(11) YASUMURO, Y. , et al. , Induced pairing between a ^heat (Triticj-n aestivum n Agropyroa d )an n elongatum chromosome, Can . GenetJ . . Cytol 3 (19812 . ) 49-56. (12) SEARS, E.R., Transfe f aliengenetio r c materia wheato t l n I , "Wheat science-toda d tomorrowan y " (L.T. EVAN d W.Jan S . PEA- COCK Eds.), Cambridge Univ. Press (1982) 75-89. (13) KIBIRIGE-SEBUNYA, I. and D.R. KNOTT, Transfer of stem rust resistanc o wheat e t fro n Agropyroa m n chromosome havin a gametog - cidal effect, Can Genet. J . . Cytol 5 (19832 . ) 215-221. (14) CEOLONI, C., Incorporation of a mildew resistance gene derived fro . longissimuT m m into common wheat through crossing-ove- be r tween homoeologous chromosomes, Proc. XXVIII Annual Meeting of the Italian Societ r Agriculturafo y l Genetics, Bracciano, Rome (1984) 94-95. (15) CEOLONI Tnticu, ,C. m longissimum chromosom G ditelosomie - ad c dition lines: production, characterizatio d utilizationan n , Proc. 6th Int. Wheat Genet. Symp., Kyoto, Japan(1983)1025-31.

(16) CEOLONI, C. and G. GALILI, Chromosome arm location and mode of expressio a phosphodiesteras f o n e gene from diploid wheat Tri- ticum longissimum, Cer. Res .4 (1982Comm3- 0 1 ). 151-157.

175 (17) CEOLONI . ROSSIL GIORGI, d C. ,,an Researc. B , n triticalo h n i e Italy: results from conventiona d novean l r breeding techniques, Proc. Int. Triticale Symp., Sydney, Australia, Austr. Instf o . Agric. Science, occasional publicatio 4 (19862 ° n ) 428-433. (18) . STRAUSSI FELDMAN d an genomA ,. M , e restructuring genn i e Aegilops longissima, Proc h Int6t . . Wheat Genet. Symp., Kyoto, Japan(1983) 309-314.

176 EFFECT OF GAMMA RADIATION ON IMMATURE WHEAT EMBRYO CULTURE

Mingwei GAO, Zhuging LIANG, Ziongying CHEN Zhejiang Agricultural University, Hangzhou, China

Abstract

e possibilitTh f o usiny g in-vitro culture f o commos n whean i t connection with mutagenic treatment is discussed. Seeds, pro and young embryo d calluan s s were irradiated with various dose f gammo s a rayse Th . observed variation in the awn types is suggested as an indicator of the mutagenic effec n thii t s combined treatment e variantTh . s frequencr fo y the pooled M-^ donors in S^ generation was about 14% in comparison to e in-vitrth f o o % 6 contro d e oveusuaan th l r l frequenc r awninfo y g 3 generationM d mutatioan 2 M n wheatn i si n .

lut £od uc_t_i_on

s ofteha nt I been reported tha a great t diversit f desireo y d variants could be frequently detected in somaclonal progenies originating from somatic tissue culture, particularly from immature wheat embryo culture (Larkin et al, 1981 and 1984). This has aroused the extensive interest of wheat breeders. Some workers have used either chemical mutagens (Hibberd, 1982) or ionizing radiation in in-vitro culture systems in an attempt to enhance the variation frequency and spectrum. Results were obtained in tobacco, potato, rice and many other species (Van Harten et al., 1981); (Shanghai Institute of Plant Physiology, 1975) but rarely in wheat.

o majoTw r problems shoul e considereb d d prio o addint r g mutagenic treatments to the in vitro culture system. First, the effect of the added treatment n o callus s formatio d shooan n t differentiation. Treatments would be of little practical value if a severe reduction occurs in callus induction and plant regeneration. Secondly, the magnitude of contribution made by additive mutagenesis to somaclonal variation. One of the studies e havw e paseo yearth mad tw ts n aime i ewa s t findina d e answere th gth o t s above mentioned questions, with emphasi n evaluatioo s e feasibilitth f o n y of the combined technique in plant breeding. Several sets of experiments were involve thin i d s study. e resultth Som f e giveo e sar s followsa n :

Seeds i rradiated with gamma rays Dry dormant seeds (13% moisture content) of seven wheat genotypes were exposed to 30 kR gamma rays at 30 R/min, then grown as M^ plants, from whic e immaturth h e embryos (embryo ^ plantM f o ss constitute already M2 progeny), 15 days after anthesis (April of each year), were excised, surface sterilized and placed on modified MS culture medium. The constituent e changef mediuo th s d f 2,4-an o ms D conten t varioua t s stages were sam s describeth ea e n previoui d s works (Sear t al.e s , 1982). Calli were produced within two weeks, shoot regeneration was not promoted until late October e seaso th ,r whea fo n t r regionsowin ou e regeneraten Th i g. d plantlets were transplante e pot greenhousen th i s o e fielt th r o o dt d .

177 In 1984, more than 230 plantlets regenerated from seed-irradiated parents were obtained, and 168 seed bearing plants were harvested for investigation. The response of expiants from 7 genotypes to in-vitro conditions is demonstrated in Table 1.

Table 1. Comparison of callus induction frequency (GIF) and shoot differentiation frequency (SDF) between expiants fromM and froe controth m l

Ex plan t donorsf o . o N GIF SDF emb r y o s T. difference e c en r l e f f i d (Ml - CK) (Ml - CK)

(1) Young 4, CK 64 43 .8 32 .1 Young 4, Ml 160 95 .0 51.2** 1 7 .0 -15.1 (2) R. R. 2 , CK 98 63 .3 45 . 1 R. R . 2 , Ml 40 92 .5 29.2** 51 .4 6.3 (3) 79 P- 17K C , 56 25 .0 7 •7 79 P- 17 , Ml 196 88 .5 63.5** 22 .3 15.3 (4) Nu. A . 1 , CK 161 37 . 5 25 .0 Nu- A . 1 , Ml 98 86 .7 49.2** 31 .7 6.7 (5) 908 , CK 416 34 .9 14.5

908 r Ml 143 42 .7 7.8 34.5 20.0*

(6) Zhe • 2 , CK 248 64 .1 1 6 . 7

Zhl eM •, 2 48 91 . 7 27 .6** 5 1. 18 .2 (7) 2 . E. , CK 16 . 6 3 0 2. E ., Ml 55 83 .6 77.3** 22 .2 22.2** Total and mean K grouoC f p 1059 44.2 21.2 Total and mean l grouoM f p 740 83.6 39.4** 25.0 3.8

* and **: significant at 0.05 and 0.01 level.

The results revealed that both callus induction frequency (GIF) and shoot differentiation frequency (SDF) are genotype-dependent. The GIF ^ groue M valugenotype th e f som o pef th o ereachen i s o abovt d e 90%, wherea s merel e wa lowes th se yon t 43% .A simila r case happeneF SD o t d e samvalu th ^ group M en i e .

e comparisonTh s mad n eaci e h pair betwee ^ dono M nd parenan r t donor favoureI expiantM e th d se average th whica highe n d F o hvaluha GI ,r e e thaparentath n l explants e meath ,n difference (39.4%) being statistically significant. As regards SDF value, the difference between the two groups was so small (3.8%) that it could be regarded as a consequence of experimental error. Thus, the seed irradiation, or more precisely e maturth , e embryo irradiation, seeme o pla t dn activ a y e roln i e

178 promoting callus induction, while keepin e samth ge regeneration capacity as the untreated one. Furthermore, seed irradiation also helped to extend the duratio f plano n t regeneratio y aboub n 0 days1 t % , 10 leadin a o t g increase in plantlet production.

Frequency of variants in S^ somaclones A diversity of morphological variations were found in S^ population (here S^ designates the first generation of regenerated plants). Among somaclonal variatio n e typchangs probablaw th nwa e f o e mos th yt common one, like the leaf colour variations appearing in M2 generation in mutation breedin f diploio g d species n typ Aw n hexaploii .e d wheas ha t been considered a stable inherited character with high heritability. Extensive studie n awnino s g inheritance have shown than developmenaw t t was controlled by five or six major genes (Ausemus et al., 1973). Alteration of awn type in wheat, therefore, would be a result of gene mutatio r chromosomao n l aberration, bot f whico h h might have taken place e coursith n f in-vitro e o culture.

It might be appropriate to take the awn type variation as an indicato o t reflecr d measuran t e mutagenith e c effec f o in-vitrt o culture. Base n thiso d , variants frequency with n typregaraw n i eo t d ^ populatioS s determinedwa n d comparisonan , f frequencieo s s betweeo tw n eacn groupi hd paian s r were also made e resultTh . e show ar sn Table i n . 2

e expiant-donorTh s tested here were sam s th listeea e n Tabli d , 1 e but classified into three groups accordin n typesaw o t .g Grou I pinclude d three pairs of fully awned donors, in each pair, one being the parent donor, e anothecounterpartth ^ M r o variatioN . e paren th s see n wa ni tn donors. Among 84 regenerated plants from M^ donors, 7 plants were found to be awnless, one awnleted, the variants frequency amounted to 9.5%. Abundant evidence has indicated so far that awnless and awnleted are dominant over awned (Ausemu t al.e s , 1973). Hence, variant f suco s h kinds could be assumed to have resulted from gene mutation in the dominant direction if the variants had normal fertile spikes, or from chromosome aberration f theri s e were problem n variantsi s ' seed setting.

Most of the variants were normally fertile in our study, thus the awnless and awnleted character would most probably be the outcome of gene mutations with dominant genes in homozygous or in heterozygous stage.

Group 111 consisted of another three pairs of awnless donors. There appeared two awnleted variants from parent donors, two awnleted plus ten awned variants fro^ donorsM- m e variantth , s frequency being 3.7r %fo paren^ donorM d 20.37 an r t fo so respectively e lattee th valuTh f .o r e s threwa e time e sformer th tha f o t, showin n additiva g e mutagenic effect e maturth f eo embryo irradiatio e enhancementh n o n f awnino t g variation.

s obvioui t I s e thaawneth t d variation appearin n Groui I g II p (awnless donorsa highe d ha )r frequency thae awnlesth nd awnletean s d variants in Group I (awned donors). This phenomenon seems to coincide with the empirical fact that recessive mutation occurs more often than dominant mutation.

From the bottom line of Table 2 we can see that the variants frequency for the pooled M^ donors in S^ generation was 14.3%, predominatin e gcontro th tha f o tl (5.97, d ovee actuaan )th r l frequency obtaine r awninfo dß generatio M gr o mutatio 2 n wheaM i n n i tn mutation breeding practice.

179 Table 2. Comparison of awn variation in S.. populations

Va riet i e s and No . of No . of variant s F r e q . of Ml coun t e rparts pl ants awn lese t e s1 n a w d awne d total I. Awne d (1 ) Young 4, CK 14 0 0 0 0.OOO Young 4, Ml 33 6 1 7 0.212 . R . R (2 ) 2, CK 21 0 0 0 0.000 R. R. 2 , Ml 18 0 0 0 0.000 - p 9 7 (3 ) 17 , CK 1 0 0 0 0.000 79 pl -M 1 7, 33 1 0 1 0.030 Sum : CK 36 0 0 0 0.000 Ml 84 7 1 8 0.095 II . Awn 1 eted : (4 )K C , N1 u . A 11 3 1 4 0.364 Nu. A. 1 , Ml 25 4 0 4 0. 160 Sum : CK 11 3 1 4 0.364 Ml 25 4 0 4 0. 160 I I. AwnI l ess: (5 ) 908,CK 35 1 0 1 o .029 908, Ml 37 0 7 7 0. 189 (6 ) ZhK C e ., 2 19 1 0 1 0.052 Zhe. 2, Ml 13 0 1 1 0.077 E.. 2 (,7 ) CK 0 o planN t r egene rated 0.OOO 2.E. , Ml 9 2 2 4 0.444 S um : CK 54 2 0 2 0.037 Ml 59 2 10 12 o . 203 Total CK 101 3 3 0 6 0.059 Ml 168 1 1 3 10 24 0. 143

Inheritance of the various awn characters Samples were taken fro 2 S linem s derive ^ dvariantS froe r th m fo s studying the inheritance of varied awn characters. Of the four 82 progeny lines derived fro_ awnlesS] m s variant n Groui s 1 p(awne d donor, e segregate on I YounM , 4) gr awnlete fo d d awnean d d wit a ratih f 1:1o o , another one completely restored to awned, the other two breed true for awnless. The $2 lines from S^ awned variants in group 3 (awnless donors ^ 908,M ) breed trur awnedfo e .

Results of analysis on the inheritance of varied characters including n typaw eo latet fro ^ S rm generations wil e giveb l n othei n r papers.

180 Accordin r observationou o t g a larg, e e varienumbeth f do r characters ocurring in S^ generation wore inheritable. It is suggested that field selection should be carried out in S^ generation if tissue culture really become n effectiva s e toor planfo l t breeding.

Pro-embryos and young embryos irradiated with gamma rays Adult plant f fouo s r wheat genotypes were R gammexposek 1 ao t rayd s at eithe e pro-embryonith r r youno c g embryoni 8 dayc r so stag 1 afte( e r anthesis respectively). Immature embryos (15 days) were excised from the seed f treateo s d plants, followe e samth e y b dstep s describea s d above.

Pooled results showed that expiants e pro-embryonitreateth t a d c a greatestag d ha e r averagF valuGI f eo e (88.3%) whic s twicwa hs muc a e h as the control, but a lower SDF value (7.6%), only half as much as the control, and finally causing a marked decrease in plantlet production.

Expiants e yountreateth t ga d embryonic stage produce a betted r result, the SDF value going up to 30.3%, while that of the control was only 12.1%. As regards GIF value, both the treated and the control reached a high level, 84.7% for the treated group and 86.3% for the control; no significant difference was found between them. Consequently, the treatment brought in more regenerated plants than the control.

s alsi ot I evident that treatmen e younth gt a tembryoni c stags wa e preferablo embryonipr e th o tha t ect a tstage , becaus e formeth e r helped to produce more plantlets.

e abovBaseth n eo d fact d usin an e suntreate th g d a standardone s a s , e differenth t type f responso s f treateo e d embryos coul e summarizeb d t a d three stages: callus initiation, shoot regeneratio d shooan n t production (Table 3).

Table 3. Different types of response of treated embryos

Developmental Dos% Callue s Zshoot % s h o o t stage induction differentiation production R ProembryK ascendinl o g descendi ng descending Young R embryK equa1 o l ascending ascending Mature embryo 30 KR ascending equal ascendi ng

As far as the shoot production rate is concerned, the second and third treatment n Tabli s 3 e seememorb eo t deffectiv e thae firsth n t one. That the second treatment had a higher rate depended mainly on the increasF valueSD f o ,e whil e thirth e d F valurelieGI n eo d increase. Unfortunately o alterationn ,6 26 n type aw th en i sf wero ey an foun n i d Sj^ regenerated plants from expiants treated at either pro-embryonic or young embryonic stages. On the basis of awn type variations, it is therefore impossible to make a comparison of frequency of variants and mutagenic effects between pro-embry d younan o g embryo treatmentr o , between these two treatments and the treatment of mature embryo. At the present time, no conclusion can be drawn from the limited facts that treatmen t pro-embryonia t r youno c g embryonic stage s lesi s s effectivs a e compare treatmeno t d maturf o t e embryos.

181 Calli irradiated with 1 kR or higher dose of gamma rays Calli from twelve genotypes were irradiated with 1 kR gamma rays 66 days after inoculation e resultTh . s were very discouraginge th n O . whole a drasti, c reductio n shooi n t differentiatio s observee wa nth n i d treated culture s comparea e scontrol th o e t frequencdth , y fallino t g 4.7%, significantly lower thae control'th n s 21.0% n additionI . , nearly half of the genotypes completely lost the capacity to regenerate after treatment with radiation. The facts implied that 1 kR might be, in general, too high a dose for wheat callus.

Morphological observations and investigations of the treated callus were conducted 3 months after treatment. Most of the irradiated culture was characterized by a peculiar dark yellow color, hard texture, lower proliferation rate, fewer fresh weight grain, larger mean siz f cello e , more giant cells d pooan , r cell content, etc. When callu s treatewa s d with TTC solution, only a few spots that scattered sparsely on the callus1 periphery turne dn colour i ligh d re t. Above all e cultureth , s a wer n i e senility stage, having entere e senescencth d e phase much earlier thae th n control.

Calli fro 9 othe2 m r genotypes wer, 12 e , allote 8 e expose b , 5 o t do t d 25, 35, 45, 55 and 100 kR gamma rays respectively. All irradiated ealli failed the regeneration of plantlets. According to our observation, the dose of 5 kR seemed to be the starting dose which caused the calli to cease shoot differentiation, and 25 kR was a critical dose that completely inhibited the callus growth. In conclusion, it must be pointed out that treatment of callus with a dose higher than 1 kR is of less practical valu n wheai e t mutatio s detrimentan it breedin o t e du gl effect n calluo s s regeneration potential.

REFERENCES

AUSEMUS, E.R t al.e . , 1972), "Genetic d inheritance"an s , Whea d Wheaan t t improvement, 2nd ed, American Society of Agronomy, Inc, 226. HIBBERD, K.A. et al., 1982, Proc. Natl. Acad. Sei., USA 7,9: 559. LARKIN, P.3 .t al.e , 1981, Theor. Appl. Genet : 19760 . . LARKIN, P.J. et al., 1984, Theor. Appl. Genet. 6^: 443. SEARS, R.G. et al., 1982, Crop Sei. 22: 546. Shanghi Institute of Plant Physiology, 1975, Acta & Genetica Sinic : 3112 a . VAN HARTAN, A.M. et al, 1981, Euphytica 30: 1

182 IN VITRO CULTURE IN BARLEY BREEDING*

K.N. KAO Plant Biotechnology Institute, National Research Counci Canadaf lo , Saskatoon, Saskatchewan, Canada

Abstract e mosth t f o usefu e On l biotechnic r planfo s t breeders i s in vitro culture of anthers or miscropores to induce haploids and homozygous tiiploids. High frequenc f microspore-deriveo y d diploid plants coul e produceb d y culturinb d g anther n Ficolo s l medium e segregatioTh . n ratio f certaio s n morphological characters wer t randono e d coulan me shifte b a y culturb d e conditions. It was reported by a number of authors that true breeding and highly productive genotypes were obtained from microspor - derivee d diploid plant d doublean s d haploids derived from bulbosom techniques. Thera grea s i e t possibility that a selective system for desirable characters can be built in an in-vitro culture system.

Where haploid e induceb n n croca si d p plants, they provide the most rapid technique for producing homozygous lines. Since e geneticallth y controlled factor n homozygoui s s linee ar s fixe d wil e an identicadb l e futurth n i el generationst i , becomes possible for a plant breeder to evaluate quantitative characters such as yield and quality very early in the breeding program [1].

There are two methods which have been used extensively for production of homozygous diploid barley plants. They are bulbosum technique d anthean s r culture methods.

* NRCC No. 25107.

183 A. The bulbosuin techniques [2,3].

Uhen diploid cultivated barley were pollinated by pollen from Hordeum bulbosum, fertilizatio d occurdi n . Howevere th , _H_. bulbosum chromosomes were selectively eliminated resulting in seeds that contained immature embryo f haploio s d cultivated barley. Some of the embryos could develop into plants by embryo culture technique. Homozygous diploid plants coule b d obtained by treating these haploids with colchicine.

B. Anther culture methods.

Since Clapham [4] reported in 1973 that haploid barley plants could be produced by culturing anthers on agar medium, very little progress was made in the next 10 years. Huang et_ 198n i 4 ] reporte[5 ^ a d thamaximue th t m yiel f planto d s from the bulbosum technique was 15.4 per 100 florets pollinated, whil e highesth e t 0 antheryiel10 f greer o d pe s n5 plant0. s wa s cultured from the same hybrid material. They concluded that unti e problemth l f pooo s r regeneratio d higan n h numberf o s albinos from microspor ee overcom b call n e ca bulbosui th e m technique will remain the method for haploid production in barley breeding programs.

e Planth t a Biotechnolog , He y Institute, (former Prairie Regional Laboratory), National Research Counci f Canadao l , have spent sometim o studt e y technique r inductiofo s f haploio n r o d homozygous diploid barley plant by the anther culture method. We are now able to produce up to 100 green plants per hundred anthers cultured. This madwa s e possibl y overcominb e o tw g obstacle n barlei s y anther culture techniques e obstaclOn . e was that the anthers or calli tended to sink and die within a w a dayliqui fe n i s r d ou mediume othef th o H d rp an , tha e th t culture medium usually gradually acidifie o suct dn exten a h t thae callth t i wer o longen e r abl o growt e . These problems were resolve y increasinb d r cultur ou e initia f th go eH p medial , e bufferinth g abilite culturth f o y e media with KHCO^y b d an , increasin e densite culturth gth f o ye media with Ficoll [6,7,8].

184 Our results indicated that the frequency of pollen callus formation in anthers could be substantially increased when barley anthers were mad o float a eliqui n o t d medium containing Ficol 0 (Tabl40 l . I) e

Tabl . I Effece n pollef o Ficolo t 0 n40 l callus formation

No. of calll per 100 anthers cultured Variety M/BT K42M/BT 59/Jet TR/SF S/S T275/S

With 10% Ficoll 8 3 309 7 11 220 2 8 37 Without Ficoll 10 4 33 2 19 2

Furthermore were w , e abl o increast e e frequencth e f o y pollen plant formatio y increasinb n e Ficolth g l contend an t reducing the sucrose content (Table II).

Table II. Effect of Ficoll on pollen plant formation.

Osniotic1 g/ a _Ejxp_ejyiment Experimen? t

Ficoll Sucrose Glucose Calli plants Calli Plants per 100 per 100 per 100 per 100 anther anther anther anther

100 90 17.5 356 11 200 60 17.5 436 40 716 15 300 25 5.0 - 200 40

routinelw no e War ey 1 (w/vadding/ 0 ) 30 gFicol l 400, 42.5 g/1 sucrose and 2.5 g/1 (w/v) glucose in our barley anther culture media. The composition of one of our media is listed in Table III.

185 Table III mediu.A r cultun'nmfo g barley anther.

a) Mineral Salt (mg) Sequestrene 330Fe 38

i\H A» M U j*\ 600 K I 0.75 l Cf ^ H fN 67 H3B04 3.00 KN03 2200 HnS04.H20 10.00

CaCl2 2H20 445 ZnS04.7H20 2.00

MgS04 7H20 310 Na2Mo02.2H20 0.25

KH2P04 170 CuS04.5H20 0.025

NaH2P04 H20 75 CoCl2.6H20 0.025 KC1 150

b) Sugar) (g s Glucose 2.5 Ficoll 300 Sucrose 42.5 Xylose 0.15

c) Organic acids (mg) (adjusted to pH 5.5

with (NH4OH) Sodium pyruvate 5 Malic acid 10 Citric acid 10 Fumaric acid 10

d) Vitamins (mg) Inositol 100 Fol ic acid 0.2 Nicotinic acid 1 p-Ami nobenzo ic aci d 0.01 Pyridoxine.HCl 1 Biotin 0.005 Thiamine.HCl 2 Ascorbic acid 1 D-Calcium pantothenate 0.5

) e Hormones w (mgbarlero 2 )y 6 row barley 2.4-D 0.5 2.4-D 0.5 - 1.0 Zeatin riboside 1.0 Zeatin riboside 0.25

) f Vitamin-free casamino acids (mg) 250

g) Coconut Water (ml) 10 From mature fruits: heate0 3 60°o r t d fo C min and filtered

) h Glass distilled water (ml) 1,000

(NaOH)6 H p . ) i Filter- sterilized

186 The procedures of our anther culture method are as follows: Anthers (20-30 in number) containing microspores (pollen) at early to late uninuclear stages were removed asep- tically from barley plantf o d allowel an m s 3 o float 2- d n o t Ficoll mean urn (Table III) in a 60 mir Falcon petri dish and r dayincubatepe t d ) s m lighhr di 9 n ti dr (lesfo x s lu tha 0 5 n 20-22°C. Whee polleth n n call1 io t a diametegre 1 o t w0. f o r sizn ma 20-2i m (c e 5 days), they were expose o stronget d r light a 100(c 0 lux d wer)an e provided with additional culture medium with lower leve f 2.4-Do l . After another 10-20 days e call,th i r embryoids(o ) were place a floate n o d n liquii r d medium with the same components as the anther culture medium (Table III) except tha containet i t o Ficolln d e amounth , f sucroso t s ewa increase 0 g/16 o ,t d 2.4- s reduce1 mg/wa Dd zeatin0. an 1o t d - w barleyro ribosid e amoun 2 5 mg/Th . r 0. f 2.4- o 1fo td o t ean D zeatin-riboside for 6 row barley were 0.25 and 0.1 mg/1 respectively. The floater was made by coating the edges of a piece f polyesteo r fabric with paraffin .e callr th Som (o if o e embryoids) developed into seedlings in one to two weeks time. The seedlings were transferred onto agar medium devoid of plant growth substances and then into pots. Over 95% of the transferred seedlings survived.

Some morphological character d isozyman s e patterno tw n i s small populations of green pollen plants from F, hybrid barley have been studied e resultTh . s indicated thae segregatioth t n of certain characters were not random (Table IV) [9].

The w typesegregatioro s6 coulo t e w b dn ro rati2 f o shifte y changinb d e amounth g f zeatin-ribosido t n anthei e r culture media. Generally, in the pollen plants derived from 2 row x 6 row (or 6 x 2) F, hybrids more 6 row than 2 rows were foun , dhybriF whee th nd anther d beeha s n culturew lo n i d zeatin-riboside and high 2.4-D medium (Table V). The result indicated that selection would be achieved during androgenesis [8].

187 Table IV. Segregation of morphological characters in pollen plants fro , mhybridsF .

Characters Segregation ratio Observed Expected w ro 6 : w ro 2 3:14 1:1 2 2 row : 6 row 15:45 1:1 Rough : Smooth Awn 11:6 1:1 Roug Smoot: h n Aw h 27:33 1:1 Black : Yellow Lemma 12:3 1:1 Green : Orange Lemma 3:14 1:1 Covered : Naked Seeds 6:5 1:1 Black 6 row Orange : Others 8:7 1:7 Tetraploid : diploid : haploid 2:40:18 ?

Table V. Effect of zeatin-robiside on segregation ratio of pollen plants from F. hybrid barley.

Source of Zeatin- No. of s v w ro 6 2 row anthers riboside plants Segregation ratio mg/1 Observed Expected

} F t Je 5 0x 0.5-1 17 1:1.43 1:1 ) 2 x 6 ( 0.25 21 1:0.21 1:1

K14K16x 9 j 9F 0.5-1 38 1:0.52 1:1 (2 x 6) 0.25 74 1:0.3 1:1

Whee barleon n y pure line whic produced ha h gree% 27 dn pollen plants (a total of 15 plants) was crossed with another pure line whic produced ha h gree % 30 dn pollen plant a tota( s l of 57 plants), the F, produced 54% green pollen plants (a total of 271 plants). A pure line which consistently produced a high frequency (82%) of green plants was selected out from them. These results indicated that genetic recombination is involved.

188 Whe a varietn y whic d produceha h d essentially albino pollen albinol planal , a tota8 s ( femalt)a f o l e parent v/as crossed wite purth h e line whic d produceha h % gree82 d n pollen plants (a total of 105 plants), the F, produced 61% green pollen plants (a total of 31 plants) indicating that the tendency to form green pollen plants is controlled by nuclear gene(s) [8].

Agronomic performance of homozygous diploid barley

Song j?t_ _al_ [10] reported that there were no differences in yield whee bes 0 th nline1 t s from bulk plot derived lines were compared with best 10 lines from haploid derived lines by the Bulbosum technique. Reinbergs et al [11] reported that under Ontario conditions, homogeneous and homozygous lines derived by Bulbosum techniques were as good agronomically and have yields s e stabllicensea th s a e d cultivars develope y conventionab d l breeding methods.

Friedt and Foroughi-l/ehr [12, 13] reported that true breeding and highly productive genotypes were obtained from microspore (pollen)-derived diploid plants. The mean grain yield of doubled haploids was usually lower than the midparent mean. However, the yield of the best doubled haploid line s slightlwa s y poo r betteo r r thae besth nt parents. Dr . Rossnagel of the University of Saskatchewan (Personal communication) indicated thae besth t t doubled haploid linesf o fro , F m Abee x Norbert was slightly lower in yield than the best pedigree lines froe samth me cross combination.e th Mos f o t doubled haploid lines ripened slightly earlier than the pedigree lines.

Variation in agronomic characters of microspore-derived plant f Hordeuo s . Sabarlicv m bees ha sn reported [14]. How- ever, Rossnagel (Personal communication) indicated that microspore-derived diploid lines of cv. Elrose by Ficoll method were uniform within the lines and among the lines in agronomic characters studiede lineth l s Al fro. , hybridF m f Abeo s x e Norbert were uniform within the lines.

189 Perspective

Since large numbers of microspore-derived calli can be induced by anther culture methods, we should be able to increase further the frequency of microspore-derived plants. Thera grea s i et possibility tha a tselectiv e e systeb n ca m establishe e tn-vitrth n i d o syste r isolatinfo m g salt tolerant d diseasan e resistan te microspor planth t a t e stage; perhaps even yield e coulw f i ,d fine correlatioth d n betwee e growtth n h vigor in vitro and in vivo.

REFERENCES

[1] KASHA, K.J., REINBERGS, E., "Achievements with haploids in bôrley research and breeding", The Plant Genome (DAVIES, D.R. and HOPWOOD, D.A., Eds), The John Innés Charity, Norwich (1980) 215. [2] KAO, K.N., KASHA, K.J., "Haploidy from interspecific crosses with tetraploid barley", Proc d Internat2n . . Barley Genet. Symp. July 1969, Pullman, Wash., Washington State University Press (1971. )82 ] KASHA[3 , K.J., KAO, K.N., "High frequency haploid production in barley (Hordeum vulgäre L.), Nature 225 (1970), 874. ] Clapham[4 , "Haploi,D. d Hordeum plants from anthern sj_ vitro", Z. Pflanzenzüchtg 69 (1973), 142. ] HUANG[5 t aj_.£ , , ,B. "Th e relative efficienc microsporf o y e cultur d chromosoman e e eliminatio s methoda n f haploio s d n production in Hordeum vulgäre L." Z. Pflanzenzüchtg 92 (1984), 22. ] KAO[6 , K.N., "Plant formation from barley anther cultures with Ficoll media", Z. Pflanzenphysiol, 103 (1981), 437. [7] KAO, K.N., HORN, D.C., "A method for induction of pollen plant barley"n i s , Proc h Intl5t . . Cong., Plant Tissu& e Cell Culture, Tokyo (1982) 529.

190 ] KAO[8 , K.N., HORN, D.C., "Inductio f polleo n n plant formation in barley anther culture", Internat. Symp. on Genetic Manipulatio Cropsn i n , Oct., Beijing (1984). [9] KAO, K.N., e_t ^., "Inheritance of certain genetic traits in pollen plants from F, hybrid barley", The Genetics Societ f Canadao y , Bulletin 14., (1983. )D7 [10] SONG, L.S.P. i al_.,"Double,£ d haploibule th k s plov d t method for production of homozygous lines in barley", Z. Pflanzenzüchtg, 81, (1978) 271. [11] REINBERGS, E., et aK , "Yield stability of double haploid lines of barley", Can. J. Plant Sei. 58 (1978) 929. [12] FRIEDT , FOROUGHI-WEHR,W. "Fiel, B. , d performancf o e androgenetic doubled haploid spring barley fro, F m hybrids" Pflanzenzücht. ,Z 0 (19839 g ) 177. [13] FOROUGHI-WEHR FRIEDT, ,B. "Agronomi, ,W. c performancf o e androgenetic doubled haploid line f Hordeuo s m vulgäre", Proc. 5th Intl. Cong. Plant Tissue & Cell Culture, Tokyo (1982) 557. [14] jjl_.POWELLt er , , "Variatio,W. e agronomith n i n c character f microspore-deriveo s d plant f Hordeuo s m vulgäre cv. Sabarlis", Heredity 72 (1984) 17.

191 SEMI-DWARF MUTANTS AND HETEROSIS IN BARLEY /. The use of barley sd-mutants for hybrid breeding

. MALUSZYNSKI*M . SZAREJKO**I , . MADAJEWSKI***R , , A. FUGLEWICZ** . KUCHARSKA*M , * * Plant Breeding and Genetics Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna * Departmen* f Geneticso t , Universit f Silesiayo , Katowice, Poland * Plan** t Breeding Station, Polanowice-Lagiewniki, Poland

Abstract

Short stature, spring barley routants obtained after chemical or physical mutagenic treatment were evaluated as a possible source of dwarfism in barley. Genetic analysis of 35 mutants indicated non-allelic relationships. o dwarfinTw g genes dw- d sdw-1an b were localizes n wa chromosomo d t I . 3 e observed that out of 190 various morphological, physiological or isoenzymatic mutants 2 wer12 ,e mutated simultaneously r alssemi-dwarfo o r o dwarf f stature. In many crosses between mutants or between mutants and parents, a very high heterosi s observedwa s e heterosiTh . s manifestatio n i s E'-nwa ^ observed for four characters; height, tillering or number and weight of grain f induceo e r us plant dpe e semi-dwarfTh . n alternativa s a s r hybrifo e d barley production is discussed.

Evaluation of semi-dwarf forms for spring barley improvement was initiated at the Department of Genetics, Katowice, about 12 years ago. The investigations followed earlier studies on the susceptibility of different varieties to chemical and physical mutagens. 35 varieties cultivated at the time in Poland were treated with the mutagens. The mutagenic treatments as well as the growing of M^ plants was usually performed in our Department. ^ M generation o t 2 M se Th wer ee experimentath grow n i n le th field f o s Plant Breeding Station Lagiewniki e chemicaTh . l N nitroso-Nmutage( H MN n - methylurea) was used in most cases. The method of treatment was described in detail befor y Maluszynskb e a (1978); Maluszynsk Maluszynskd an a i (1983). Fast neutrons (from U-120 cyclotron e Institutth f o e f Nucleao e r Physic n Cracowi s ) and sodium azide (NaNj) were used in a few cases (Skawinska-Zydron and Fatyga, 1978; Szarejk Maluszynskid an o , 1980).

193 1. GERMPLASM COLLECTIO f SHORO N T STATURE SPRING BARLEY MUTANTS

1.1. Evaluation of dwarf and semi-dwarf mutants

Collection f mutanto s s with semi-dwar r otheo f r desirable characters were assembled and grown in the two locations for the following purposes: Department of Genetics, Katowice - genetic analysis and agronomic evaluation of mutants Plant Breeding Station, Lagiewnik - evaluatioi f yielo nd diseasan d e resistance and cross breeding

Mutants from 13 varieties were maintained in both collections. Semi-dwarf forms were collected from 10 varieties. Out of 515 mutants collecte n 1984i d 3 ,wer33 e cemi-dwar d dwarfan f . Genetic investigations using barley marker stocks and allelism tests between mutants are still in progress.

Tabl 1 listee numbeth s f r o mutantcollectionrou n i s d theian s r relative height. In the selection of mutants from M2 to M^ progenies, other than semi-dwarfness agrobotanical traits were mainly considered. Many dwarf forms for this reason, mainly from the varieties Julia, Delisa and Plena wert includee no collectioneth n i d t meanI e .numbe th s f shoro r t stature forms now existing in the collection does not reflect the total frequency of induced sd-mutations r exampleFo . e highesth , t frequenc f mutanto y s with this character was observed in the M2 progeny of Julia variety but there are now only 39 mutants in the collection from this variety. Over a period of a few years (1980 to 1984) Aramir and Karat became the most popular varieties in our experiments, enabling us to collect numerous mutants from them.

TABLE 1: Number of dwarf and semi-dwarf mutants in our collection in height classes relatee heighth f o theio t td r parent cultivars (1984).

Cultivar Mutants' height classes (% f pareno t variety) Name Height (cm) 40-49 50-59 60-69 70-79 80-89 Total

Julia 77,,4 + 3.2 1 11 23 3 1 39 Delisa 80,,5 + 2.0 28 - 7 6 1 42 Plena 95.,2 -t- 1. 6 -- 2 5 -- -- 7 Aramir 79,.3 + 4.9 1 6 18 13 12 50 Diva 86,,9 + 4.6 2 4 8 6 5 25 Georgia 71 .2 + 4 .6 -- 1 -- 3 2 6 Mg 4170 76 .9 + 7.2 1 8 7 8 2 26 Trumpf 74 .0 + 1.7 -- 2 — 4 27 33 H DM 77 .0 + 2.4 -- -- 1 6 5 12 Karat 71 .8 ± 3.4 2 7 11 14 59 93

TOTAL 35 41 80 63 114 333

It should be noted that all parent varieties used by us are already short statured in comparison with the varieties grown in Europe at the turn of the century (Rigg t al.e s , 1981). Still e higth ,h frequenc f sd-mutanto y s r induceexperimentou n i d s demonstrated that shorter stature mutante b n ca s very easily induced by mutagenic treatment in them too. The cultivar Trumpf,

194 which was released in the DDR in 1973, originated from the cross of several source f diseaso s e resistance wite mutanth h t variety Diamant, itsela f semi-dwarf form obtained after x-ray treatment of the "tall" variety Valticky e collectedW . , after mutagenic treatment 3 mutant3 , f Trumpo s f with shorter straw - of which 2 were dwarf.

It appears that stem length and spike length are under separate genetic control n almosA . t norma r eveo l n longer spik s observe wa 6 e9 shor n i td stature mutant f differeno s t varieties (Tabl . Fiv2) e e mutants 3 ,semi-dwar f ) hav AR a vere 2 y28 lon, AR g 3 (lax03 , DV ) 8 21 an , 2 dwardAR f1 08 (08 , 0AR spike. An independent mutation, induced simultaneously with the sd-mutations is supposed to be responsible for this type of spike. This suggestion will be e subjec th a separat f o t e genetic investigation.

TABLE 2: Number of short stature mutants in different classes of straw or spike length in relation to their parent varieties.

Length classe f pareno % ( st variety)

30-39 40-49 50-59 60-69 70-79 80-89 90-99 100-110 111+ Total

Stra6 w 34 54 65 67 104 3 333

Spike 5 16 30 69 117 71 20 333

Generally it is possible to say that straw length was reduced more often and more drastically thae e spikeslengtth th n f o h. Example f mutanto s s with very short straw and normal spike length are presented in Table 3.

TABLE 3: Examples of short stature mutants with almost normal length of spike

Mutant Straw length, Lengt f spikeo h , parenf o % t % of parent cultivar cultivar

571 DK 38 .9 97 .1 639 DK 60 .8 98 .1 845 PK 57 .8 99 .0 040 AR 67 . 7 90 .8 215 DV 59 .3 93 .3 438 MG 68 .2 94 .0

It is encouraging that grain yield components of short stature mutants were often not affected. Since 1983, 305 mutants have been evaluated for the number of grains per plant. 33 of them have a similar or higher number of kernels thae parenth n t cultivars, even such successful one s Aramira s , Trumpf and Diva (Tabl . 4) Examplee f o semi-dwars f mutants with high yielding capacit e e giveshortest-straTh ar n yTabli n. 5 e w mutan n thii t s high yielding grou d stilha p l 73.2e parenth %f to variety's height. Shorter, dwarf type mutants usually displayed poor yielding capacity.

195 TABLE 4: Number of semi-dwarf mutants in grain number classes related to grain number per plant of their parent varieties (1984).

Variety Grain number Yield classes (H of parent variety) per plant < 21 21-30 31-40 41-50 51-60 61-70 71-80 81-90 91-100 101 + Total

Julia 140 5 29 7 4 11 9 6 4 3 1 38 Deli sa 161 1 62 2 6 5 7 12 5 3 3 1 42 Plena 126 6 21 3 -- 2 1 _- -- 1 1 2 7 Aramir 145 3 24 9 2 3 9 5 7 5 3 1 2 -- 37 Diva 165 2 28 9 3 5 6 2 4 3 - 2 25 Georgia 153 8 24 3 -- 2 3 1 -- - 6 H DM 137 4 22 4 — 3 2 4 1 - - 1 11 Mg4170 116 3 2 28 3 4 3 3 2 3 2 3 -- 3 25 Trumpf 164 9 38 6 2 4 5 6 4 3 3 1 5 33 Karat 171 1 10 8 4 4 12 8 12 9 10 8 5 9 81

Total 22 46 52 52 41 29 22 11 22 305

Table 5: Semi-dwarf mutants with the highest number of grain per plant.

Mutant Height, % of Grain No./plant, parent cultivar of parent cultivar

223 DV 74..4 152,.3 428 MG 88,.0 153,.2 445 MG 73,.2 143,.2 562 TR 88,.8 138,.3 715 Q 85,.5 155,.2 823 Q 75,.1 179,.1 862 Q 88,.6 176,.0 888 Q 89,.2 126,.0 914 Q 86,.3 130,.6 364 HD 76,.1 129,.4

1.2. Genetic analysis of short stature mutants

Allelism s tesbee ha 5 tcross-combination5 n n carrieo t ou d 5 3 f o s mutant n i orde o st clarifr y their genetic relationships. Non-allelic relations wer e4 4 crosfoun n i sd combinations. Crosse7 non-alleli f o s c semi-dwarf or dwarf mutants with their respective parent varieties gave in the ?2 monogenic segregations (Table 6). This means that 7 independent loci, responsibl r shortnesfo e f o plans t height were already found among investigated mutants. The detailed genetic analysis of interaction among these genes is presented in the second part of this paper (Szarejko et al., 1987). Continuous variabilit n plani y t heigh s observe 2 wa progeniet £' n i d s from crosses between 3 other non-allelic mutants and their parent varieties. Significant morphological differences among these 35 mutants together with preliminary results of complementation tests suggest that the number of independent semi-dwarf or dwarf loci is much higher.

196 TABLE 6: ?2 segregation in crosses of 7 short stature mutants with their parent varieties.

Cross combination No. of plants X2 P Total Tall Dwar r o f (3:1) serai-dwarf

392 JK X Julia 497 373 124 0.00* 0. 98 0,.95 409 JK X Julia 423 314 109 0.13 0. 80-0.. 70 555 DK X Delisa 555 424 131 0.58 0. 70 0.,50 599 DK X Deli sa 109 85 24 0.52 0. 70-0.,50 648 AK Xr i Aram 325 243 82 0.01 0.95-0.,90 862 PK X Plena 417 303 114 1.21 0.30-0.,20 267 MK X Mg4170 379 276 103 0.96 0.50 0.,30

*/ X2 = 0.00067

Result f genetio s c analysis using translocatio e followinth no t line d gle s conclusions (Szarejk Maluszynskid an o : , b) 1984 d an a

- dwarf K (nemutanA w8 r collectio64 numbet ou ) n AR i r 5 03 n is determined by a new, recessive allele of brachytic (br) locu n chromsomo s , firs1 e t describe y Powerb d s (1936).

e locuth s- dw-1 locate n chromosomo d responsibls i 3 ee th r fo e dwarf character of the mutant 862 PK

e semi-dwarth - f characte K mutan(nee M th w7 f 26 numbeto r n i r our collection 437 MG) is determined by the locus sdw-b on chromosom3 e

e Witexceptioth h , othe AK f o mutann r 8 64 analyset d mutants were non-alleli£ genb d non s an allelie ez wa gene eu th o o d t .t cc an Botu uz h brachytic mutant e usuallar s y considere e mosth t s a importand t sourcef o s dwarfnes - eves n though they have undesirable pleiotropic effect n mani s y climatic conditions.

2. HETEROS1S

2.1. High frequenc f mutaRenio y c event n celi s l nucleus after mutagenic treatment with "supermutagenes"

NMH and also sodium azide, which was used in a few cases, are very effective mutagens for mutation induction in barley (Konzak et al., 1975; Maluszynski, 1982; Szarejko and Maluszynski, 1980). Our experiments furnished sufficient evidence to confirm the conclusions of Loesch (1964) and Hansel (1966) that by using highly effective mutagens in the methodology we developed usually more than one mutation event per cell nucleus is induced in the generative line (mutation rater survivinpe s g M^-nucleus) e commonlTh . y accepted opinion, that onle gene'on y s difference exists betwee e variouth n s mutant lines and their parent varieties, is based on studies with a limited number of characters. Listed below are examples of many cases of semi-dwarf or dwarf mutants which have an identical phenotype and similar agrobotanical performanc e differinar e isoenzymatit th bu e n i g c spectrum (Tabl: 7) e

197 Table 7: Mutations in isoenzymatic loci of short stature mutants.

Parent varietied an s Isoenzymatic loci** their mutants_ wit__ h identicar o ~ sd l dwarf-phenotype Est Kst 3 Est 4 6-PRdhl AcPh 1

Plena fast slow slow slow 841 PK* fast fast fast fast - 862 PK* slow slow fast slow _

Julia slow slow K J 2 39 slow slow - - K J 9 39 fast fast _ _ -

Delisa slow fast K D 8 62 slow - fast - K D 8 63 fast _ slow _

Diva slow slow 203 DV* fast - - fast 256 DV* slow - - - fast

/ * Genetic analysis indicated allelis f theso m e formr fo s sd-character. **/ Nomenclature after Kahler et al. (1981). Loci Est 1 and Est 3 are closely linked (Kahler and Allard, 1970).

Similarly, out of 190 various morphological, physiological or isoenzymatic mutants described in our collection, 122 were mutated simultaneously also for semi-dwarf or dwarf stature. It should be noted that in this e collectiocasl th line al en i s n were screene r onl fo 5 dtrait1 y s e genetiTh (Tabl . c 8) e analysi 0 independentl1 f o s y induced mutants wite th h 6 row character indicated that they were allelic to locus y on barley chromosom. 2 e

Similarly, the elongated glume mutation was allelic to gene e located on 4 investigate2 f o chromosom t Ou d. 2 emutant s with dense spike e (32) on , 1GK alread s foun wa s ya alleli d o t locuc s ert- n o chromosomc 3 e(Ga d an j Haluszynski, 1985). Two short hair rachi.Ha mutants were allelic to gene s locate n chromosomo d . 7 e

198 TABLE 8: Examples of morphological, physiological and isoenzymatic mutant n collectioi s 5 mutan51 f o tn stocks (data froe th m 1984 season).

Mutation Numbe f mutanto r s Total With simultaneous mutation(sn i ) dwarf or sd-loci

Chlorophyll 27 11 Improved powdery mildew resistance 21 16 Isoenzymatic loci 69(108*) 42(66*) Increased internode number 1 1

Grain and spike morphology Dense 27 23 Lax 5 5 6- row 11 - Intermedium 1 - Collar mutation 14 14 Elongated glume 1 - Short awn 5 4 Lateral flower reduction 1 1 Short hair rachilla 5 4 Hooded ( calcaroides) 1 1 Black lemma and pericarp 1 -

Total 190 12^

*/ Numbe f recordeo r d mutations, some mutants containe2 d mutation r moreo s .

The concept of high frequency of mutations per cell nucleus was confirmed in our experiments on heterosis effect in F^ progeny of crosses between mutants froe samth m e parent variety.

2.2. Heterosis manifestation n mutani s t crosses

To avoid a heterosis effect in such a character as plant height, mainly semi-dwar r dwaro f f mutant d theian s r parent varieties were used in these experiments o T describ. e potentiath e l heterosis effecn i t crosses between ^ mutantplantF e th ss were grown space planted (24x25 cm. n mosi ) t field experiments. Because lac f th gametocideo k f o e l al s crosses were don y handr b ethi Fo .s reaso e numbeth n f planto r r eacfo s h replication and the number of replications had to be limited to 5. The general scheme of experiments is presented on Fig. 1.

199 Genetic Material Work backgrund

Homozygous seeds Mutagenic of spring barley - treatment variety_____

e sameTh , M2 to M5 Selectiod an n parent or M6 self-pollination variety progenies

F1 Progeny Type of crosses: I/Mutant var.A x Mutant var. A Crosses between 2/Mutant var.A x Parent var. A homozygous mutant lines and 3/Mutant var.x A Mutant var. B varieties 4/Mutant var.x B Parent var. A

Different

Control Crosses between Variety A x VarietB y varieties

Figure 1: Design for asessment of heterosis effect in crosses of spring barley mutants with each other or with parent cultivars

The first results of these experiments were published by Maluszynski (1982) n manI .y case a vers y high heterosis effec s observewa t^ F n i d crosses between mutants as well as between mutant and parent or other e varietysamth e t A time. , heterosi s notew controwa sn fe onl i da y l combinations, especially between distantly related varieties. Results focusin n heterosio g n mutani s t crosse e presentear s n thii d s paper.

Four lower-yielding mutants of the variety Aramir were used in experiments n 1985carriei t .ou d Agronomical characteristic f theso s e lines are presented in Table 9. Two semi-dwarf lines, 282 AR and 239 AR, had very low yield components in comparison with the parent variety e leadinth Arami f o g re varietieon whic s i h n Polandi s w numbeLo .f o r grain r planpe s t (54.2 d 28.3%%an , respectively n comparisoi ) o Aramirt n , as wel s verw a grail lo y n weight (only 37.0parn i o d t 17.9%te %an du s )i very poor tillering even in widely spaced growing conditions.

2QO TABLE 9: Agronomie characteristics of four mutants from the variety Aramir (data from 1985).

Mutant or Height Tillering Grain per plant parent var. (cm) Number Weight (6)

Arami r 89 .4 + 7. 6 16.45 6. +- 273 .9 + 98.4 8.9 + 3.7 233 AR 91 .2 + 7.4 12.7 + 4.4 213 .1 + 82.8 6.1 + 2.7 239 AR 64 .9 + 8.5 4.2 + 1.7 77 .6 + 46.4 1.6 + 1.0 R A 0 28 87 .9 + 4.7 15.8 + 4.3 237 .4 + 80.1 6.9 4- 2.4 282 AR . 79 0 .+ 1 4 11.6 ± 2.5 148 .5 + 73.9 3.3 + 1.5

The heterosis manifestation in F^ 282 AR x 239 AR was observed for four characters in comparison to both parents and their average. These two poor yielding mutants produce ^ hybridF d s wit n extremela h y high increasf o e both yield components (Table 10). Grain weigh r planpe t t increasen i d relatio o bettet n r paren r 263.6fo t d grainan % s numbe r plan r pe 171.5r fo t % Similar data in relation to poorer parent is of course much higher. It was only due in part by increase of tillering from 11.9 or 4.2 to 18.8 tillers per plan t othebu te responsibl b r o factort d r yielha sfo e d improvemen s wella t . Such extremely high result f o heterosi se useb o demonstratt dn ca s e th e potential valu f variouso e , often poorly performing mutant r heterosifo s s programmes.

These results may be explained by a high level of heterozygosity in F^ hybrids. Thiy indicatma s e agai a "supermutagen s na thaH MN t " induce a gread t number of mutations per surviving M^-nucleus. However, taking into consideration thae significanth t t heterosis effec s observewa t f o d 4 onl n i y abou 0 crosse2 t f variouo s s semi-dwarf Aramir's mutants s possibli t i , o t e conclude that specific genes, which directly or indirectly affect yield had to be involve n mutatioi d n event d thaan s t heterozygosito n s a sucs yi h sufficient explanation of the phenomenon.

TABL : 10 EHoterosi s manifestation f increaseo . ^ (7 sF n i ) progenie f Aramir'o s R A s mutan9 23 x tR A cros 2 28 s in relation to both parents (1985).

Percen f increaso t e over: Character______mutan R A R mutan A 2 paren 9 28 t 23 t t mean

Plant height 30.9 41.4 36 .0

Tillering 62.1 347. 6 138 .0

Grain No/plant 171. 5 419.6 256 .6

Grain weight/plant 263. 6 650.0 389 .8

s verwa yt I clearly demonstrate e basia cros th f o sn s o d between mutants 282 AR and 239 AR that agronomic performance of mutants can not be used as screening critérium for good combining ability. The mutant 239 AR was used as a cross component three times in the four crosses where the heterosis effect s observewa d (Table 11). Verw yiel lo d pooy an dr tillerin f thio g s mutant

201 drastically increased the indexes of all hybrid F^ characters in relation to the same mutant characters s agrobotanicaIt . ll characteristial t a t no s i c attractive for plant breeders: short stature (only 65 cm) with weak straw, large leaves, lax spike (about 14cm) inside a flag leaf sheath and late maturated.

Hybrid plants showed better tillering in all cases, especially in the e increasTh . f planAR o e 2 tt 28 significan heighno x s R A wa t 3 n i 23 t f o 1 F relation to parent variety due to the use of semi-dwarf mutants as components for these crosses. This result demonstrates that the use of mutants from the same parent variety as cross components for F^ hybrids gives opportunity to avoie complementatioth d n effec f o great t numbe f geneo r s regarding such characte s plana r t height (tall hybrid) becaus f similao e r genetic background of both parents except one or two sd-genes which differ both these mutants.

TABLE 11: Heterosis manifestations (% of increase in relation to Aramir) f Aramir'o iF n s mutant crosses (data from 1985).

Cross Height No. of spikes Grai r planpe n t r planpe t Number Weight (cm) (%) (No.) (%)) (% (No.) S <*)

Aramir x 239 AR 90.8 1.62 1. 16.6 362 .4 32 .3 * 11,.2 25 .8 * 280 AR x 239 AR 94.4 5.6 18.4 12.2 374 .4 36 .7 * 12,.9 44 .9 * R A 9 23 x R A 2 28 91.8 2.7 18.8 14.6 403 .2 47 .2 ** 12,.0 34 .9 ** R A 2 28 x R A 3 23 95.6 7.0 20.6 25.6 424 .8 55 .1 ** 13,.2 48 .3 ***

< 0.0 p 5* ** p < 0.01 *** p < 0.001

The highest heterosis manifestation was observed in the F^ of 233 AR x 28? AR. Very high grain number (424.8), as well as weight of grains (13.2g) per plant were observed parallel to very rich tillering (20.6 spikes). It should be noted that the difference in height of plants between the tallest parent (233 AR - 91,2 cm) and F1 plants was only 5,5 cm and was not significant in relation to the parent variety Aramir.

Statistics proved that a heterosis effect was observed also in the cross e parenth f to variety Arami t manifestateI r . wits mutanAR it h9 n bot23 ti d h grain yield component t withoubu s y changean t n suci s h character s heigha s r o t Heringi t .

e heterosiTh s manifestatio t limiteno s o e mutantt varietdwa th n f o sy Aramir. A similar effect was observed in crosses between semi-dwarf or normal tall mutants from variety Diva, for example. Heterosis was observed in crossing Diva wits mutantit h s wella s . Manifestatio f heterosio n s effect varied n thii , s experiment, from yea o yeat t rstil bu r l exceede e betteth d r F parenthybrid e Th . s between parent varietV D s mutan it y5 Div12 d t an a

1 achieved the highest yield in this group of crosses in both years. This hybrid combination gav n 198i e 5a ver y high yield increase 87.6 d 115.3%an % r graifo n numbe d graian r n weigh r plantpe t , respectively e samTh .e semi-dwarf mutant 125 DV was the component of two other mutant crosses in whic e heterosith h s effect manifestatio s verwa n y high (Table 12).

202 TABLE 12: Heterosis manifestations (% of increase) in crosses of Diva's mutants in comparison with the better parent and check cultivars in years 1984, 1985.

Cross Height Spikes Grai nr planpe t No /plant Number Weight 1984 1985 1984 1985 1984 1985 1984 1985

DV x 134 DV a -1 0 5 84 3 8 0 - 6* 0 7 53 8* -8 1 52 9* b 14 8 44 1 67 2 73 3

V D 5 12 x V D 1 2 - a 11 52 *6 * 6 1 3 7* 7 8 * 45 5 6* 61 5* 115 3* b 14 8 43 4 67 7 86 7

V D 6 11 x V D a -4 2 3 9 5 * 8 2 2 5* 33 4* 82 6* 0 8 * 32 7 0* b 7 1 40 .6 63 5 56 0

V D 4 13 x V U 5 12 a 13 4 0 15 38 6* 14 4 68 9* 16 5 72 9* b 12 9 48 3 83 7 96 0

V D 4 13 x V D 6 11 8 4 - a -2 1 08 8 5 64 19 9 22 24 7 b 6 3 16 1 30 3 41 3

V D 6 11 x V D 5 12 2 8 1 a 19 4 17 5* 20 6 20 8 32 7*8 3 2 9 1 5* b 4 5 9 6 18 8 20 0

*/ p < 0 05, calculated only to better parent (') a/ increas n comparisoi e o bettet n r parent b/ increase in comparison to check cultivars

e expressioTh f o heterosin n relatioi e sorigina th o t n l varietr o y better parent was evidently lower in our experiments in 1984, perhaps because of extremly good climatic conditions for spring barley cultivation- a very wet and cooy wit Ma la relativelh y summerdr y . Hybrid f barleo s y mutants seeo t m express a better adaptability in adverse climatic conditions, as in 1985 A dry May together with a delay in sowing due to a wet last decade of April was probabl e reaso th yr relativelfo n y lower yielding parenta d checan l k varieties (Table 13).

TABLE 13 Meteorological data of 1984 and 1985 for the experimental field Boguchowalowice (Katowice).

Month Temperature (°C) Rainfall (mm) 1984 1985 1984 1985

March 0.4 2.2 17 .0 37 .2 April 7.4 7 .4 17 9 64 .5 May 12.4 14 2 128 .3 58 .0 June 14 0 13 .4 52 6 103 9 July 15.0 17 .1 74 4 93 4 August 16.9 16 .8 53 .8 153 .2

203 2.3.___Induced semi-dwarfs n alternativa , r hybrifo e d barley production?

Hybrid vigour in barley mutant crosses has been described in many mutation breeding experiments. Gustafsson (1946 a revie n i ) we th pape n o r effec f o heterozygositt n o variability d vigouan y r presented examplef o s hybri f crosseo d ^ vigouF sn i rbetwee n spontaneou r o induces d chlorophyll mutants. Heterosis manifestatio n i vigou ns founwa r d under shory da t conditions also in crosses of early mutants (Gustafsson et al. 1973). Hagberg (1953) obtained "superdominance" in total plant weight, yield of grain per plan d tillerinan t n crossei g f o differens t erectoides mutants with their parent line.

Similar results were publishe r othefo d r crops A suprisingl. y large amoun 4 f percenheterosio t10 o t n grai i tp u sn yield abov e morth ee productive parent was described by Jones (1945) in crosses of maize spontaneous mutants with parental homozygous lines. It has to be noted that all these mutants were classifie s carryina d g "degenerative changes" suc: narroas h w leaf, dwarf typ f growtho e , pale chlorophyl d crookean l d stalks, blotched lead latan f e flowering. The author concluded, from results of these crosses that "heterosis could result from a single allelic difference if the change involved more than a single function". Unfortunately, data about segregation 2 ? progeniein s t havbeeno e n presente r otheno d r results which could provide additional support for this statement. Gottschalk (1968, 1976), on e basith f o detailes d genetic studie f o Pijnjs m mutants, clearified that seemingly pleiotropic action of mutated genes very often can be explained as simultaneous mutations of neighbouring, closely linked genes. The concept of so called "monohybrid heterosis" was revised first by Doll (1966) and than by other authors (Lönnig, 1982; Gottschal d Wolffan k , 1983)

Craigmiles (1968) informed about heterotic effect f dwaro s f genen o s forage productio n Sorghui n m vulgäre var. sudanense Hitch. Corny (1976) described heterosis effec n i crosset f o Petunis tllarx a a is (Lam.) Juss. mutants obtained after MNH treatment. Drastic increases of greon matter production, considerably above the level of the parent variety, were observed in the Kj of low glucoside induced mutant crosses of Melilotus albus DESK (Micke, 1976). Stoilov and Daskalov (1976) presented data on general and specific combining abilit f o inducey d maize mutants. Inter-mutan^ F t hybrid f Sesamuo s m indicu . gavL m a heterotie c effec n seei t d yiel d numbean d r f capsuleo s (Murty u (1982L d , an )1979) u founQi .d that \ t heterosi e th n i s of Arachis hypogea L. mutant crosses was more significant than the fr'-^ heterosis of original varieties. It should be noted that these mutants can not be directly used as new, improved varieties.

Lehman (1981 n papei ) r with title "Wher s hybrii e d barley today?" w techniquene f o r hybrie fo sus presente de w th barleideafe n o a sd y seed productionf themo l ,a basial thers a neef A o o havs .t i d e e hybrid plants which are profitable. We demonstrated that semi-dwarf mutants used as components of hybrid crosses can express a very high level of heterosis in such important character s a numbes r o weighr f o grair t planpe d n an t tillering. These results were obtained in space planted trials which gave an opportunity to describe the yielding potential of inter-mutant or mutant x parent variety crosses. Stiff, semi-dwarf mutants with proper differences in plant height between both parent r morfo s e effective pollinatio a sterile f o n , female component, will necessaril e needeb y r hybrifo d d seed production with the use of gametocides.

Collection f semi-dwaro s n alternativfa mutante b n r ca traditionasfo e l source f hybrio s d cross component e mutanth f i ts heterosis wil e confirmeb l d in farmers field conditions. This approac f o semi-dwarf e us h e witth ,h intra varietal mutants for hybrid seed production has important advantages in compariso e traditionath o t n l one. Mutants user hybrifo d d production differ

204 only in limited number of genes. It means that other important characters, particularly of the grain, such as grain quality, cooking quality, taste, malting characteristics could remain in homozygous stage and therefore would not segregate in the harvested product of t'-^ plants (as would be easily the case in distant hybridization) because of the same genetic background both cross components which originated from the same parent variety. This is extremly importan r cereafo t l hybrid production where semi dwarf staturf o e e plantth , wit s physiologicait h l implications e maintaineb o t s ha d, together with other important characters of the present day ideotype to win competition with high yielding comercial varieties.

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SZAREJKO MALUSZYNSKI, I. , , (1980,M. ) Analysi f usefulneso s f sodiuo s m azid plann i e t breeding. Acta Biologica, Katowice : 60-669 , .

SZAREJKO MALUSZYNSKI, I. , , (1984a,M. w brachytiNe ) c mutan f sprino t g barley variety Aramir. Barley Genetics Newslette : 33-3514 r .

SZAREJKO, I., MALUSZYNSKI, M., (1984b) Two new dwarf ism genes on barley chromosome 3. Barley Genetics Newsletter 14: 35-38.

SZAREJKO, I., MALUSZYNSKI, M., NAWKOT, M. SKAWINSKA-ZYDRON, G. , (1987) Semi-dwarf mutants and heterosis in barley. II. Interaction between several mutant genes responsibl r dwarfisfo e barleyn i m . TECDOC, IAEA, Vienna n press)(i , .

206 BIOCHEMICAL ASPECT COLF SO D DAN HEAT SHOCK RESPONSE IN BARLEY*

N. MARMIROLI Institut f Geneticseo , Universit f Parmayo , Parma M. KOMJANC, C. LORENZONI Institute of Botany and Plant Genetics, Universit f Piacenzayo , Piacenza M. ODOARDI, V. TERZI, A.M. STANCA Experimental Institutr fo e Cereal Research, Fiorenzuola d'Arda, Piacenza Italy

Abstract

Studies with barley plantlets (cv. Onice) showe e appearath d n ce of at least five major proteans(MW = 22, 47, 70, 85, 94 Kd ) after a temperature shift up (heat shock) from 24° to 40°C. The synthesis of these heat shock proteins has been related with acclimation or thermoprotection of barley seedlings to elevated temperatures e havW . e also analyze e modificationth d s in proteins synthesis followin a temperaturg e shift-down from C (col0° o dt shock)° 24 e synthesiTh . f threo s o fivt e e polypeptides (cold shock polypeptides, CSPs obtainewa ) d under this condition. Synthesi s followe wa f theso s P n differenCS ei d t parts of the same plant and in two different cultivars: Onice and Georgie. The identificatio f specifio n c HSPd CSPan s s could offee th r opportunity to clone some of their structural genes by complementary DNA synthesis and to analyze in the molecular details their genetic regulation and their dependence on the specific genes.

Researc* h work supporte parn i dy Italia b t n Ministr f Agricultureo y , Progetto "Tecnologie Avanzate", in part by CNR-Italy, special grant IPRA-subprojec. 1 t Corresponding authoM Stanca A r , Istituto Spenmental a Cereahcoltural r pe e . Sezioni d e Fiorenzuola d'Arda, Via S Protaso, 308, 1-29017 Fiorenzuola d'Arda (Piacenza), Italy

207 Temperatur e majoth e rf variatioo factore on s i sn controlling plant growt d reproductionan h n croI . p plants, whee finath n l e reproductivyielth r o d e capacit s influencedi y e stresth , y sma resuln economia n i t c disaster n facI e .agronomica th t l practice has evidenced that in cultivated plants rapid step-up and down above the normal temperature (heat shock and cold shock) can modify the expression of a particular genotype. However the plant can react to the thermal insult in several manners. These mechanisms have the purpose to survive the plant to those environmental modifications which represent the temperature extreme f theio s r . habita2) , (1 t Surviva o thest l e otherwise lethal temperature d deserveha s d particular interest also because there coul e somb d e relationship with the capacity to adapt at those temperature variations which n e occurfieldca th n i r. Therefor e searc th er cro fo hp plant so througg whic n ca hh the temperature variations of their habitat without significant modifications of their final yield can have a benefit for the comprehensio e mechanismth f o n s regulatin e cellulath g r response o temperaturt e insult. Anon e adaptativth g e respons o temperaturt e e changeso tw , molecular mechanisms have been identified whic e triggerear h d respectivel a rapi y b yd temperature increase (heat shocky b r )o an equally rapid temperature decrease (cold shock). Both types of response involve a modification in gene expression since the activit f somo y e gene shut-ofs i s f whereas other genee ar s shut-on. Consequently preexisting "normal" protein o longen e ar rs translated durin e stresth g s wherea n increasea s d synthesif o s new proteins is induced (2, 3). The response to heat shock in vascular plants has been describe r severafo d l species includine Th . 6) g , barle5 , (4 y major feature e planth tf o srespons s comparea e d with animal response were presencth e a larg f o ee moleculaw numbelo f o r r weight heat shock proteins (LMW n plant)i t detecteno se th n i d animal systems (7). Genes codin r som s welfo f a gthess o ea W l LM e gene se hig codinth h r moleculafo g r weight heat shock proteins (HMW) have been cloned and sequenced (8). Investigations on the hydrophi1ic/hydrophobic properties of some of the heat shock polypeptides (HSPs) showed a conservation of structural features between HSPs from soybean, Caenorhabditis, Drosophile th d an a mammalian lens «K-crystallin(9).The structural analysis carried out in one of those cloned HS genes (a gene coding for a 153 ammo acids protein) showe e presenc th dn ope a nf o ereadin g frame and several potential promoters homologou e Drosophilth o t s a heat shock consensus sequence CT-GAA-TTC-A Gp upstreab wit 5 1 h m from the TATx (fobo A r reviewa e Refse , . 10). The possible function of these HSPs and of the putative HS genes have been investigated barleyn I . soybean i s wel ,a s a l n (11), a short exposure (two-four hours) at high temperatures (50°C) determine e growt a blocsth n i hk procese younth gf o s seedlings,

208 which can not resume several days after the seedlings are returned to normal temperature. Restoration of the elongation process following a HS as well y othean s ra thermoprotecting e easileffecb n yca t detectey b d using this system n factI . , whee seedlingsth n , befor e shocth e k at 50°C e expose a shorar , r tfo d perio o temperaturet d s which induce synthesi f HSPo s s (37°-40°C t affec whict no ) bu o d th significantly the elongation process, inhibition of the growth by the second exposur s onlwa e y partia r ceaseo l d (6). Therefor e firsth e t mild temperature shock providee th s plant wit n acclimatioa h a protectio r o n n towar e exposurth d o t e otherwise lethal temperatures A positiv. e correlatio s beeha n n established between acclimation or protection against high temperature d accumulatioan s f HSPo n s (2). Other agents different from temperature which can induce HSPs (e.g. arsenite) are able to furnish a similar thermoprotection to the plant, confirming the role of the HSPs in this phenomenon (11, 12). Since the proteins induced by the HS could be different (at leas n barley i e tdifferen th n i ) te plantpartth f o s, this raises new questions about e mechanisth f acclimatioo m d thermoproan n - tection in the various parts of the plant. Firstly e synthesith s i , f theso s e different proteins related wit a tissuh e specific requiremen e procesth n i f tso acclimation and thermoprotection9 Secondly, are different HSPs really synthesized by different organs in response to HS also in adult plants, or are these differences a peculiarity of the seedling tissue9 A modification in the synthesis of individual proteins has also been evidenced when barley seedlings were exposed few hours to temperatures of 5°C or 0°C (3). Attempts were made to study protein synthesis below the freezing temperatures, but the results wert significantlno e y differen t -5°C a te effec Th . f o t temperature step-down (cold shock) involved the synthesis of new protein e disappearancth d an s e norma th f som o ef lo e proteinst A . 0°C only the cold shock proteins (CSPs) were present, whereas most of the normal proteins disappeared. Different organs of the seedling synthesized some CSPs which were common whereas other CSPs were detected a specifionl n i y c organ. The synthesis of CSPs as the synthesis of HSPs could also be directe n vitri d y purifieb o d messenge A isolateRN r d from shocked tissues or plants and this is currently utilized to produce cDNA e clonemajoth rf o s HSPs e compariso.Th y hybridizatiob n f theso n e cDNAs wit e cloneth h S geneH d s will elucidat e differenceth e d an s e similaritieth s existin e genetith n i g c determinant r colfo s d and heat shock proteins. The functio e CSP undes th i s f o nr investigatione th t bu , preliminary experiments indicate that they could hav a role n i e thermoprotectin e planth g t agains e verw temperaturesth tlo y .

209 Within the important issue of both cold and heat tolerance in plants a particular interest deserves the study of mutants e geneth in s e colencodind heath an dr t "o shocg k proteind an s of the effect of mutations in these genes upon the acclimation and thermotoleranc whole th ef eo plant . Mutants of these genes can be identified in the progenies derived from mutagemzed parent s wel a s constructea ls vitrn i d o by usin e cloneth g d shock genes. Forthis purpos e availabilitth e y f reliablo e technique r mutagenizinfo s g both plant d isolatean s d gene sf majo o wil e rb l interes e developmenth n i t f planto t s with modified response o temperaturt s e stress. The selection among these mutants, from those with particularly favorable adaptability to extreme environments, should produce proper genetic material from which seed productivit d othean y r economic '"raits can be evaluated.

REFERENCES

[l] MASCARENHAS, J.P., "Advances in Agricultural Biotechnology" (COLLINS, G.B., PETOLINO, J.G., Eds) . NijhoffM ,. W . Dr , Junk, The Hague (1984) 391. ] KIMPEL[2 , J.A., KEY, J.L., Trends Biochem. Sei 0 (19851 . ) 353. [3] MARMIROLI, N., TERZI, V., ODOARDI STANCA, M., LORENZONI, C., STANCA., A.M., Protein synthesis during cold shoc barlen i k y tissues. Compariso o genotypetw f o n s with winte d sprinan r g growth habit (1986) In press. [4] MEYER, Y., CHARTIER, Y., Plant Physiol. 72 (1983) 26. [5] COOPER, P., HO, T.H.D., Plant Physiol. 71_ (1983) 215. [6] MARMIROLI, N., RESTIVO, F.M., ODOARDI STANCA, M., TERZI, V., GIOVANELLI TASSI, B. ,, LORENZONI F. , , GenetC. , . Agr. 30 (1986). ] KEY[? , J.L. t al.e , , "Current Topic Plann i s t Biochemistrd an y Physiology" (RANDALL, D.D., BLEVINS, D.G., LARSON, R.L., RAPP, B.J., Eds) Vol. 2, Univ. of Missouri-Columbia Press (1983) 107. [s] SCHÖFFL , RASCHKEF. , , NAGAOE. , , R.T. ,3 (1984 , EMBJ. )C 2491. ] INGOLIA[9 , T.D., CRAIG, E.A., Proc. Natl Acad. 7 7 Sei A US . (1980) 2360. [lu] BIENZ, M., Trends Biochem. Sei. 10 (1985) 157. [il] LIN, C.Y., ROBERTS, J.K., KEY, J.L., Plant Physiol4 7 . (1984) 152. [12] NOVER, L., HELLMUND, D., NEUMANN, D., SCHARF, K.D., SERFLING, E., Biol. Zentralbl. 103 (1984) 357.

210 PHYSIOLOGICAL TEST DROUGHR SFO T TOLERANCE IN BARLEY AND DURUM WHEAT*

. MARTINIELLP O Istituto Sperimentala l r epe Cerealicoltura, Fiorenzuola d'Arda, Piacenza G. BOGGINI Istituto Sperimentala l r epe Cerealicoltura, Catania Italy

Abstract

Physiological test r characterizinsfo g drought tolerancn i e barley (H. vulgäre L.) and durum wheat (T. durum L.) were evaluated. These tests involved: 1) germination in osmotic solution (-13 atm by d-mannitol) ) therma2 ; l stres n seedlingo s s hours)5 (42° r fo C ; ) stabilit3 e cellulath f o y r membrane under osmotic stress (PEG 600 43%)t 0a r bot.Fo h species genotypic variability whics wa h associated with drought tolerance in the field was identified by the laboratory evaluation techniques. Based on these procedures, the two-row barley types were more drought tolerant than six-row types. In durum wheat, only some local populations and some varieties, bred in drought environments, showed high laboratory test values. Weak and not significant correlations were found between the physiological tests indicating that the genetic mechanisms which control these traits may be independen d process-specifican t . Yield trials barleyn i , , have been carrieenvironmentn i t ou d s with drought conditione th d an s correlation between grain and physiological tests were significant. Of the three procedures evaluated in this study, the dry matter increase afte peraora f thermao d l stres d electrolytan s e leakage seememose b to t dreliabl potentialld ean y usefur fo l screening for drought tolerance in barley and durum wheat.

e wors supporteTh wa k) e Ministèr* th y b d e Agricoltur e Foresta e grant - Progetto Cereal:: Sottoprogetto "Orzo" and "Frumento duro".

Corresponding author P Martmiello, Istituto Sperimentale per la Cerealicoltura, Sezione di Fiorenzuola d'Arda, Via S Protaso, 308, 1-29017 Fiorenzuola d'Arda (Piacenza), Italy

211 INTRODUCTION High temperature and drought are notorious both for their unpredictable variability from location to location and their ability to limit the yield of crop plants in many agricultural regions of the world (Lewis and Christiansen 1981; Blum 1983; Martiniello 1984). In cereals most of the progress in breeding for drought toleranc s beeha e n achieve y usinb d g empirical methodsn I . practice a drought tolerant cultivar is defined as the one making e greatesth t yield with limited soil moisture. However better progress could be made if the physiological responses of plant to drought were known and could be used in selection programs. Breeders and physiologists are looking for ways to measure d analysan e underlyinth e g physiological mechanisn f toleranceo s . e chaiTh f physiologicao n l events between gend phenotypan e s i e not known but if a key step in the chain were known to be correlated with stress tolerance, the breeder can select directly for it rather than select for the final phenotype (Sullivan and Eastin 1974; Blum and Ebercon 1981; Larsson 1982; Martiniello and Lorenzoni 1985) e succese physiologica.Th th f o s l approach will require evidence that the characters tested in the laboratory reflect drought tolerance, under field conditions. Among cereals, barley and durum wheat are two of the most important crops in the areas were high temperature and erratic rainfall occur durin e lifth g e cycle e followinTh . g three laboratory tests have been applie thesn i do species tw e . They include: a) seed gemination in osmotic solution ( GOS ) ; b) dry matter increas afte) seedlinn W i eperioa r -D N f thermao (D dg l stres greenhousee sth carrien i ) evaluatio£ t d ou e dan ; th f o n stability of the cellular membrane in presence of osmotic stress applie t flowerina d g time (LEOS).

PHYSIOLOGICAL LABORATORY TESTS - DESCRIPTION

Seed germination under osmotic solution. Seeds of all progenies were immersed for 5 minutes in a sodium chloride solution (5% v/v), washed three times and dried to prevent mould infestation, then transferred to filter paper in Petri dishes. Fifty seeds for each genotype and for each replication were distribute f e filteo th l m n o rd0 1 pape d an r d-mannitol solution at ^ = -13 atm were added. Three series of dishes were arrange germinatoa n i d t 25°Ca r , followina g randomized block design A .fourt h replication using distilled water served as control. After 8 days, the percentage of germinated seed s determinedswa (GOS) .

Seedling evaluation in heat temperature chamber. e genotypeTh s wer em diamete c grow 5 1 n poti nf ro s filled with a compost consisting of an algae-rich soil and arranged on a greenhouse bench without supplementary light A randomize. d block

212 design was used with four replications for evaluating dry matter increase afte e perioth r f thermao d l stress plu o replicationtw s s for the control. Fifty seedlings were considered for each genotype in each replication. Plant t four-leaa s f stage (15-20 days old) were well watered and the following day placed in an unlighted force dryer hours5 ai d 42°t r ra fo C. Afte e exposurrth e period, the plants were returne e greenhousth o t d d thean en rewateredn .O control replications a sampl, f thirto e y plants from each genotype s collectewa r determininfo d e initiath g l plan . y weigh) dr t W (D t Seven days later the seedlings were picked up and final plant dry s evaluatewa weigh) W r eac(D fo dt h genotype.

Leaf tissue discs under desiccation stress. Progenies were arranged in the field in a randomized block design with four replications e ploTh . t consiste^ witm a h0 1 f o d seed rate of 350 seeds/m . Two sets of flag leaf-discs were cut from plants with equivalent growth stage (determined by the flag- leaf n eac)i h plot o set .Tw f fift o s y n diameterdiscsi m m 5 , , were collecte n viali d s containin f deionizeo l m 0 2 gd watere .On see stresf disco tth s user swa fo d treatment e otheth t se rd an s served as the control. The loss of electrolytes under osmotic stress (LEOS) was measured by electrical conductivity following e procedureth s describe y Blud b Eberco an m n (1981).

EXPERIMENTAL RESULTS

Barle\ A preliminary screening test based on seedling dry matter increase after a period of heat stress, has been carried out on fifty genotypes (cultivar d breedinsan g materials). Sixteen of them have been selected and evaluated in three environments where conditions of drought are frequent (Catania, Cagliari and Foggia). In all physiological tests we were able to identify variability among genotypes (Table 1). The lack of correlation (Table 2), anong physiological tests, at different stages of growth, means that the genetic mechanisms of drought tolerance are independent, process- specifi r eacfo c h stag f developmeno e d governetan y specifib d c mechanisms with some interference in their expression. Correlations between grain yield and physiological tests were found (Table 3). The highest value was between electrolyte leakage (LEOS) and yield, which means this test may be a good indicator of drought tolerant lines e graiTh . n yield average eth (Tablf o ) 4 e genotypes (45.9 q/ha), with high physiologicae valueth f o s l tests, was 15% higher than the mean of the discarded ones (39.4 q/ha). From these varietie e founw s d that only Géorgie3 showsl al n i , stages of development, a good drought tolerance. Other genotypes have different response at different stages.

213 Table 1. Ear type (D= two-row; P= six-row), grain yield and physiological tests averages (CO Sgerminatio= n under osmotic solution; DW -DW = seedling dry matter increases after thermal stress; LEOS = loss of electrolytes under osmotic stress] of the barley genotypes in e experimentsth .

Genotype Ear Grain GOS W D - DW LEOS type yield -2 gxlO (q/ha) plant

Géorgie D 51.730.7 20.7 54.3 Gi tane 46.3 54.7 14.0 69.4 Ign 46.8 6.4 24.5 63.4 Panda " 43.71.8 12.9 67.2 Pépite " 34.38.3 15.0 78.8 Arda 45.8 2.7 18.3 49.0 Alpha 41.8 29.3 13.2 67.7 Porthos 47.7 36.1 15.0 55.1 Tipper 44.6 14.7 18.6 73.0

Arma P 37.41.3 9.5 75.6 Fior 26 " 41.22.1 8.5 69.9 Robur " 40.40.7 6.7 75.5 Pirate " 43.30.1 25.4 68.5 Vetulio 36.9 3.0 8.6 69.6 Barberousse 46.0 2.4 19.9 75.5 Jaidor 40.5 2.4 17.6 77.8

3.3 6.9 3.1 5.7 LDS(0.05)

Table 2. Correlations among physiological tests inbarley.

GOS DW - DW

GOS

DW - DW 0.0s n 5 1 0 LEOS -0.3s n 2 -0.38*

214 Tabl . Correlation3 e s among grain yiel d physiologicaan d l tests in barley.

GOS DW - DW LEOS

Yield 0.48* 0.56** -0.69*1

Tipper e highlseemb o t sy resistan e earlth yt a tgrowt h stages, while Ard d Igre toleranan aar i t from tillerin o maturitt g y f theso l eal materialn (TablI . 4) e s only Barberouss a six-ro s i e w type. Within the two-row type we found tolerance in both spring d wintean r types. This means thae two-roth t w materials coule b d the basi r developinfo s g winte r sprino r g cultivarr fo s environments with drought conditions.

Tabl . Barle4 e y genotypes with high test values.

-2 GOS X DW - DW 0 1 x g LEOS plant inJury

Gitane 54.7 Jgri 24.5 Arda 49.0 Porthos 36.1 Géorgie 20.4 Géorgie 54.3 Géorgie 30.7 Tipper 18.6 Porthos 55.1 Alp_ha 29.3 Arda 38.3 Igri 63.4 Tipper 14.7 Barberousse 19.9 Panda 67.2

X 33.1 20.3 57.8 - Discarded X 2.8 12.4 72.8 Genotypes

Genotypes without underlining appea e rtest on onl n .i y " with dashed underlining appear in two tests. " " solid " " " three tests.

Durum wheat Considering durum wheat the most important cereal crop in the areas where drough d higan th temperatur e frequentar e e appliew , d two physiological tests on the basis of the results obtained in barley. We chose 46 genotypes: 21 local populations have been tested r germinatiofo mattey dr d ran n increas seedlinn i e g d (Tablan ) 5 e 5 commo2 n varieties were evaluate r germinatiofo d e osmotith n i n c solution test (Tabl. 6) e

215 Table 5. Physiological test values in durum wheat cultivated varieties (COS d loca)an l population) W -D s W D (CO d San e codth e tes e r Tablth use se Fo tn . i 1 de

Varieties COS Local GOS DW - DW 1 0 (%) populations (%) g x 10~ plant

Adamello 53.2 Cannizzara 60.0 8.3 Aldura 48.6 Capeiti 8 * 10.0 Appio 96.0 Cappelli 13.1 Appulo 65.2 Castiglion. G e 42.5 14.2 Arcangelo 57.0 Cotrone 66.7 15.6 Brunda 52.9 Creso * 5.6 Capeiti 8 95.0 Farro Lungo 64.2 8.1 Castel lo 75.6 Gioia 92.6 8.0 Creso 62.4 Karel * 12.0 Dui 1 10 54.2 Lina 58.6 13.3 Gabbo ian 61 .1 Martinella 53.7 17.2 Japigia 42.6 Produra * 9.1 Karel 68.5 Realforte 69.5 8.3 Lira 20.0 Ruscia 71 .9 13.6 Messapia 61.1 Russello 64.9 0.4 Norba 43.7 Scorsonera 69.3 11.3 Nora 81.8 Semenzella 45.5 4.7 Piceno 67.4 Sicilia Lutri 47.0 10.1 Procace 63.8 Sicilia R.N. 47.4 10.3 Produra 73.0 Tinulia 70.8 13.4 Solitario 78.0 Trinakria 62.6 8.2 Trinakria 62.6 Tripol ino 51.1 11.2 Valforte 42.0 Tunisina 51.7 18.0 Valnova 51.4 Urria 42.9 13.5 Vespro 50.0 Valle L.G. 56.4 10.3

LSD 11.6 24.4 2.7 (0.05)

See column number 1.

r germinatioFo osmotin i n c solution (GOS a )larg e variability within in two groups of genotypes was found. Within the commonly cultivated varieties (Tabl ) wer6 e e found eight promising genotypes: Appio, Capeiti 8, Nora, Solitario, Castello, Produra, Karel and Piceno which are largely cultivated in drought environments. All these varieties have been brer specififo d c adaptatio n stressei n d environments. On the contrary, the new high yielding varieties, bre n higi d h fertile environments, have greater yield instability (Mariani et al. 1983), when grown in stressed environments, and

216 Table 6. Durum wheat varieties and local populations with high physiological test values.

Varieties Local Populations

COS % GOS % DW - DW ID-x g 2 1 0 plant Appio 96.0 Gioia 92.6 Tunisina 18.0 Capeit8 i 95.0 Ruscia 71.9 Martinella 17.2 Nora 81.0 Timilia 70.8 Cotrone 15.6 Soli tario 78.0 Realforte 69.5 Castiglion. G e 14.2 Castello 75.6 Scorsonera 69.3 Ruscia 13.6 Produra 73.0 Cotrone 66.7 Urria 13.5 Karel 68.5 Farro Lungo 64.2 Tinilia 13.4 Piceno 67.4 Trinakria 62.6 Lina 13.3

X 79.3 70.9 14.8 - Discarded 56.0 51.8 8.8 Genotypes

showed low germination values of the applied test. Within local populations we found eight genotypes with high scores when germinated in the osmotic solution test (GOS): Gioia, Ruscia, Timilia, Realforte, Scorsonera, Cetrone, Farro Lungo, Trinakria (Tabl. 6) e r thermaFo l stres sa larg e variabilit s alswa yo foundx Si . genotypes showed a good ability to recover after a period of stress o locatw le (Tabl) populationTh W (D. -D W6) e s (Timili Rusciad an a ) seem to have physiological attributes of tolerance rather than avoidance (early maturity), because they are facultative and late maturity genotypes. barleyn Ai s o correlatio,n s observewa n d between theso etw tests. This could suggest that the genetic mechanisms which control the traits are independent.

CONCLUSION D REMARKSAN S

On the basis of these results, wide genetic variability for drought tolerance can be identified by physiological laboratory tests applied at different growth stages (seed, seedling and adult plant). Obviously t explai no e dat th o ,e physiologicad a th n l mechanisms that are the basis for the correlations between stress toleranc n fieli e d conditions e resulte laboratorth th d f o san , y tests. However s likeli t i ,y thae genotypeth t s showing positive reactions to tests possess the genetic mechanisms for recovering their normal condition f growto s h afte perioa r f environmentao d l stress. The absence or weak correlation between traits evaluated by physiological tests indicate that those traits are independent

217 e regulateb y ma y differend b d an t genetic mechanisms (Sullivad an n Ross 1979; Levitt 1980; Trapan Mottd an i o 1984; Martinielld an o Lorenzoni 1985). In this regard e duruth , m wheat varieties, releasen i d stressed environments d soman , e local populations contain more favourable gene combinations for stress than the new varieties which have unstable yields in stressed environments (Fischer and Maurer 1978; Marian t a]_e i . 1983). The genotypes selected using these tests have been introduced in breeding programs for drought tolerance for developing synthetic populations through the recurrent selection method. With this cyclical method, it is possible to increase the frequency of the favourable o maintait gene d an s a largn e amoun f genetio t c variability. From these populations new advanced breeding materials extractee b n ca w cycl) parenta dne : f recurren o er fo s t selection; w varietie linene ) ) c_ s parentb a sd an sr developin fo s F g commercial hybrids. This last program can be facilitated, in the near future by using gametocides to induce male sterility.

REFERENCES

BLUM Geneti, A. , d physiologicaan c l relationship n i plans t breeding for drought resistance. Agricultural Water Management 7 (1983) 195-205. BLUM, A., EBERCON, A., Cell membrane stability as a measure of drought and heat tolerance in wheat. Crop Sei. 2^ (1981) 43-47. FISCHER, H.A., MAURER , DroughR. , t resistanc n sprini e g wheat cultivars. I. Grain yield responses. Aust. J. Agric. Res. 29 (J978) 897-912. LARSSON, S., A simple, rapid and non-destructive screening method useful for drought resistance breeding oats (Avena sativa L.). Z. Pflanzenzuchtg 89 (1982) 206-211. — nd LEVITT, J., Responses of plants to environmental stress. 2 Edition, Academic Press w Yor,Ne k (1980). LEWIS, C.F., CHRISTIANSEN, Breeding Plants for stressed environments n "PlanI . t breeding II", (FREY K.J., Ed)e louTh , a State University Press, Ames, USA, (1981 . 151-178)pp . ,'jAhIANl, B.M., NOVARO MAN MANA, P., SIEFANINI, R., Efficiency of linear and multi-phase regression methods to evaluate genotype -environment interactio r graifo n n yiel d proteian d n contenn i t Italian durum wheat varieties. Z. Pflanzenzuchtg 90 (1983) 56-67. MARTINIFLLO Drough, P. , t resistanc n

218 COMPARATIVE ANALYSI MORPHOLOGICALE TH T SA , BIOCHEMICAL AND GENETIC LEVEL TO DEVELOP A STRATEG STUDYINR YFO G BIOLOGICAL SIMILARITIES IN Triticinae

L. MONTEBOVE, C. DE PACE Agricultural Biology Institute, Universit f Tusciayo , Viterbo, Italy

Abstract

e currenTh t affinities ascertained among Triticinae specie e reviewedar s . The a searcstrateg f o o ht ascertaiy n biological similarity among Triticinae species is still a debated issue. The best approach to be used must exclude analogies as deceptive and affinities be constructed only on homologies. Previous morphological studies ascertained that the genera Secal d Dasypyruan e m were different each other d botan ,h were different from Tnticu d Aegilopsan m . However more recent cytological studies showed that certai e chromosomery n e ar s homoeologous to that of wheat; cytoplasm studies indicated that Dasypyrum villosum cytoplas s affin i me dono th o thaf t eo rf o t B cytoplas r o th S eo wheatt m ; isoenzyme protein d seean sd storage proteins pointed out to the presence in D. villosum of

genes orthologous to those in the A or B genome of wheat. Definitive answer n o sspecie s affinities have been obtained in few cases when in vitro DNA-DNA hybridization technique have been used. Therefore for future work it will be interesting to use pairwise DNA-DNA hybridizatio f representativo n e speciel al f o s Triticinae gener n ordei a o havt r a broae d significanan d t e biologicaansweth n o r l similaritie e specieth f o ss belonging to this subtribe.

INTRODUCTION e subtribTh e Triticinae includes many important crop plants and many grazing grasses. The use of the crop plants or cultivated specie f Triticinao s s beeha e n relate o different d t plant structure e e moskernelth th t e t importanar bu ss t plant organ to be used. The kernels are used for making basic foods for humans (two-layered flat breads, single-layered flat breads, pasta, cous cous, burghul, frekeh, etc. d animalan ) stra( s d an w foodstuff) e wilTh .d species belongine subtribth o t ge Triticinae are grasses covering pasture land of many European, Mediterranean, and Near East areas.

219 To the taxonomists working with economic plant, the Triticinae species group is of particular interest because a large number of its species has been used. To the plant evolutionist intereste n phylogeni de Triticinath n a , y e ar e inportant grou f o specie pr testinfo s g hypothesin o s evolutionary mechanism d speciatioan s n events. The Triticinae species have given rise to perplexing problems of evolution, phylogenesis and sistematics, which canno e resolveb t y separatb d d partiaan e l studie n plano s t structure, plant proteins, cytogenetics, genetics and molecular biology. As matter of fact, currently the studies around the ascertainment of affinities among species of Triticinae is still cause of thorny debates . e criteriTh a that have been use o searct d h affinities, among species ranged from geographical A distributioDN - A DN o t n hybridization o n instanc n I e e specie.th th e havl f o al se Triticinae been contemporarily compared for geographical distribution, morphology, biochemical properties (isozymes, seed storage proteins, aminoacid sequence of proteins, antigen- antibody reaction, flavonoids, etc.), gene and chromosomal homoeology, cytoplasm type, organelle (chloroplast and mitochondria) DNA restriction mapping, ribosomal gene sequence, in-situ hybridizatio A witRN h f r o o labelemetaphasn A DN d e chromosomes, DNA-DNA hybridization of not-repeated sequence, and nucleotide sequence of a certain gene. This is because some Tri ticinae genera (Tnticum , Aegilops and Secale ) have been studied more profusely than others (Agropyron and Dasypyrum), and even in the genera more analyzed not all the above criteria have been used. n realitI o searct y h biological similarity,e th tha s i t fundamental procedur r constructinfo e g phylogenet:c treed an s follow the evolution of a taxa, not all the above cited criteria are necessary. Goul ) indicates(1 d that biological similarity includes o entireltw y different reason r being fo o sorganism Tw . y ma s 'look alike' because both inherited a set of similar features from a common ancestor. Similarities based upon descent are called homologies t feature o Bu organism.tw f o s y alsma s o IOOK alike because both evolved independentl n responsi y o t e lifn i similae r environments. Similarities based upon independent evolutio e callear n d analogies. (Whea d broaan t d bea e annuaar n l plant d cauchgrasan s d commoan s n waterlily have rhizomes y analogb , y only. Whea d cauchgrasan t s remain Graminae by descent). Therefore statements about similarities among Triticinae species must be based on genealogy and this can be ascertained only if similarities are excluded as deceptive and the affinities are constructed only on homologies. e objecTh f thio t s o reviepapet s i re w wor th som kf o thae t has been done at the Agricultural Biology Institute, University

220 of Tuscia, Viterbo, Italy on the search of affinities in Triticinae using the approach of sorting out homologies from analogies.

CYTOGENETICAL AFFINITIES Various model f o genetis d genoman c e differentiatiod an n affinities in the species of Triticinae have been developed on the basis of chromosome pairing studies in interspecific hybrids. Many authors agree that the A genome is closely related to the genome of Einkorn wheats (2); the B genome S genomappear e relatee b th o e t so t thad s presene i t th n i t species Ae.speltoides , Ae.longissima, Ae.sharonensis, Ae.searsii, and Ae.bicornis of the section Sitopsis of the genus Aegilops genomD (3) e s contribute.Th wa e y Ae.tauschib d i (4). e homoeologe studth Th f o y y between genomee b n ca s done by crossing the species carrying different genomes ana observing the amount of pairing at methaphase I. However pairing f homoeologouo s chromosome s oftei s n prevente e activitth y b d y f suppressoo r genes, f chromosom o locate e lonm th ar g n o dB 5 e (gene Ph) (5), on chromosome 3A (6) and 3D (7).

The assumption that reduced methaphase I chromosome pairin n interspecifii g c hybrid f Triticinao s s causei e y b d structural differentiatio f o chromosomen s (inversiond an s translocations) doet agreno s e with experimental observation (8). More reasonable seem a chromosomas l differentiation associated with speciation that occur n numeroui s se siteth n i s t alterinno y genomb gd an gene e sequenc . Unevee n ratef o s nucleotide sequence chang s beeha e n postulatee o occuth t d t a r genetic level in the chromosome of the A and B genomes. Therefore it has been proposed that differentiation among Triticinae species has both a structural and a molecular component (8). This hypothesis indicates that many loci in the Triticinae although orthologous have evolved alleles that code for very different gene products. Therefore any affinity study in the Triticinae that is devoid from cytogenetics has to have a genetic background that involves many loci. Recently genome affinities has been studied using the C-banding technique. Gild Kimbe an l) comparin(9 r e C-bandinth ge th f o g diploid species T.monococcum, Ae.speltoides, Ae.squarrosa with that of A, B, and D genomes, respectively, in hexaploid wheat, conclude that Ae.speltoides could not be the donor of the B genome and T.monococcum and Ae.squarrosa are the donors of the A and D genomes respectively.

221 Teoh et al. (10), however, gave evidence that on the basis f o affinitie e C-bandinth n i s g patterns Ae.speltoided an s Ae. sharonensis could be the possible donor of the B genome of wheat.

MORPHOLOGICAL AFFINITIES The morphological approach has been used in botany at every taxa leve o creatt l e groupin d subgroupinan g o t d an g establish key to the taxa themselves. When key to the taxa are constructe e morphologicath d l system consideredt no ofte o d n consider phylogenetical, geographical, ecological and agronomical aspects. As matter of fact the key to the genera of Triticinae used for i.e. by Maire (11) is based on differentiatio w planfe tf o n organs suc s gluma hd lemman e a morphology (Tab whos) .I e alternate trait f theso s e characters are often controlled by alleles at one locus. Therefore morphology ,e situatioth eve n i n ns i whe t i n treated with sqhisticated multivariate statistical tools, cannot separate analogy from homology unambiguosly.

TABLE I TRITICINAE TH O T Y EKE GENERA ACCORDIN MAIRO T G) (9 E

Glume lirear Glum n lineano e r

Lemmas thin Lemmas thicker

Glumes with Glumes without 2-4 teeth 2-4 teeth

Glumes with Glumes with Glumes with Glumes without one keel o keelTw s keel keel i I I SECALE AEGILOPS TRITICUN DASYPYRUM AGROPYRON AGROPYRON subgen. subgen. Eremopyrun Elytrigia

222 CYTOPLASM AFFINITIES

Sasakuma and Maan (12) found that cytoplasm of !_._ dicoccoides, Ae.kotschyi, Ae.vanabills d Dasypyru,an m villosum did not have any adverse effect on the male fertility of the alloplasmic durum plants. This indicates some affinit f D.villosuo y m cytoplasm with that of the female parent in thehybridization process that lead to T.duru d representan m e firsth s t affinity evidenced between D .villosum and wheat. The cytoplasmic affinity between llosui d .v tetraploiD an m d Triticina n i lin s ei wite e th h affinities that wile evidenceb l d belo r proteifo w n genes between D.villosue diploith d an d m wheats T.monococcud an m T.urartu

PROTEIN AFFINITIES In the 1950s and 1960s it was realized that comparison of protein sequences or electrophoretic patterns could have offered potential advantages in discovering homologies because phylogenetic conclusions wer ee analysi th base n o df primar o s y gene products e assumw f I e. that similar isozyme phenotypee ar s produced by genes with similar base composition, the n the comparison of isozyme phenotypes of different species is an indirect comparison of the genes coding for those isozymes. In Tab.I a Idirec t compariso f severao n l diploid, tetraploid an d hexaploid Triticinae is performed on the basis of the genetic information available for seven isozymes and two seed storage protein fractions (13) (14) (15) (16) (17) (18) (19 paped ,an r in preparation). In wheat the genes for the isozyme phenotypes ADH-1 (20), GOT-2 , GOT-3 (21), EST-1, EST-2, EST-3, EST-4 (22) and for the seed storage proteins gliadin and glutenins (23) have been studied and their loci located on the A, B and D genomes Therefor a Triticina f i e e species shown a s electrophoretic phenotyp a protein r fo e , tha s similae i t th o t r wheat electrophoretic phenotype for the same protein, and the gene coding for that protein and its chromosomal location is known, then the species is indicated as carrying alleles similar to those in wheat (i.e. ADH-1 phenotype band 3 (Tab.Ill) is e code th n whea i y gened b d D an tn 4 chromosomeo s d an B 4 s same ban s preseni d n Ae.speltoidesi t . Therefore Ae.speltoides is considere o hav t dn allel a e r ADH-fo e 1 simila o thost r n o e genome B and D of wheat). T.boeoticum and T. urartu for 60% of the patterns studied carry alleles similaA e o th thost r n i e genome of wheat (Tab.IV). Ae.speltoides for 43% of the protein has allelessimila% 36 genomA r e o thosfo th f wheat ro e n d o ean t has allelt s similar to those in the D genome of wheat. Ae.searsn and Ae.longissima have alleles similar to those of the D genome only e tauschA . s alleleha u s simila e genom o thosth t r f D o ee in 70% of the cases. D .villosum in 57% of the cases shows alleles simila A genome.For e o thosth t r n i e Secale information

223 Ni •^ TABLI I E

SIMILARITY AMONG TRITICINAE SPECIES A.-, INDICATE Y B ISOENZYMATID D SEEAN L D STORAGE PROTEIN, GROUPING THEM ON THE PRESENCE OF ALLELEC^ LIKE THOSE CODIFIED BY CHROMOSOMES OF GENOMF.S A, B, D IN T.AESTIVUM.

P r u t, e i n Species ADH-1 GOT-2 GOT-3 FST-1 EST-2 EST-3 EST-4 Gliadins Glutenins Tota K*;) A B D A B ABD ABD ABD A8D ABD ABD ABD A B D °

Diploids (2n=2x=14. ) + T + monococcu. m t •»•+++ - * + (6) (2) (3) T.urartu ++++1- + + + (6) (2) (2) Ae.speltoides -f+t-t + + + + *• *- +• + (3) (6) (5) Ae.searsii + + + + + (0) (3) (3) + + + + + + + + . longissim + Ae a (1) (4) (5) + - -t + + +•* + + + + + Ae.tauschi+ i (1) (3) (9) - -* + + + + + D.villosum (4) (2) (1) + + . céréalS e (1) (0) (1) Tetraploids (2n=4x=28: ) T.turgidum +++++ ++++++++ + ++ ) +(8 + + * (9) (3) + + + + + T.timopheev + + + +-t + + - i (4) (5) (3) Esaploids (2n=6x=42): ) (9 ) (9 ) (9 + + - < + + + + + + + + + + + + + + + + + + + + + + + T.aestivu+ m

(*) absolute frequency of alleles similar to those controlled by chromosomes of A, B, and D genomes in

T.aestivum TABLE III

ANALOGY AMONG TRITICINAE SPECIES FOR ELECTROPHORETIC PATTERN F ADH-O ) 1(1 ISOZYMES.

Band number 1

Tetraploids (2n=4x=28)

ivuL s m de T

TABLE IV

PERCENTAG F AFFINITO E F ALLELEO Y F TRITICINAO S E SPECIES WITH THOSE CODIFIE Y CHROMOSOMB D F O E GENOME, A S B, D IN T.AESTIVUM

Percentage (*) A B D Species Diploids (2n=2x=14) T . monococcum 55 18 27 T.urartu 60 20 20 Ae.speltoides 21 43 36 Ae.searaii 50 50 A clongissim. a 10 40 50 Ae. tauschli 7 23 70 v . losu i1 D m 57 29 14 céréal. S e 50 50 Tetraploids (2n=4x=28): T. turgldum 40 45 15

timopheev. T i 33 42 25 Esaploids (2n=6x=42): T.aeativura 33 33 33

(") percentage of alleles similar to those controlled by D genome d chromosome an T.aestivun i , sB , A f o sm

225 was available only for two proteins and in one case this species showed alleles D genom similae f th o eo thost rf o e wheat These data indicate that T. monococcum, T.urartu and D. vi 1 Ipsum show the same type of allele for about 60% of the protein d thaan st these allele e similaar s o thost rn i e the A genome of hexaploid wheats. Ae.tauschu shows proteins strongly similar to those determined by genes on the D genome. Ae.searsi i and Ae.speltoides seems to show an equal proportion of protein phenotypes simila o thost r e determine y geneb d n o s D genomes d an th B e. The tetraploid e proteiwheatth f o sn sho% thae 20 war t "lectrophoretically simila o thost r e code y geneb d n genomo s D e of wheat. Becaus e cytogeneticath e l evidence excludD e th e e tetraploigenomth n i e d wheatss inferrei t i , d that several genes of the A and B genomes share homology with those on the D genome. Altnough these data confirm the cytogenetical evidence that Ae.tausch e putativth s i uD genome ee donoth t ,f no o ther o d y support any cytological conclusion about the donor of the A and B genomes n additioI . n D.villosu s showeha m a gread t affinity Afith other diploid wheate secon th d thi an s i ds evidence that .ndicate^ genetic homology between D. villosum and the wheat species . These conclusions correspond in part to the -if fini ties deduced from cytology, morpholog d geographicaan y l distributio e Triticinaeth f o n .

DNA AFFINITIES Dvorak and Scheltgen (24)investigated the homology of nucleotide sequences amon e DNA th f gwheato s ,e th rye d an , diploid Agropyron elongatu y usinb me techniquth g f DNA-DNo e A hybridization.l s showwa t n tha. A elongatut3 1 les sA DN m different from wheat DNA than from rye DNA, while rye DNA appears equally different from whea d Agropyroan t n DNA. Using a different DNA-DNA hibridization technique Nath et al. (25) were able to identify in Ae. speltoides the G-genome . timopheeviidonoT o t r . In the same study (25) there were indications that the repeated DNA fractions from the diploids Aegilops searsn, Ae. speltoides , Ae.sharonensis, Ae. longissima, Ae. bicornis and from the tetraploid T. timopheevii are more similar than the uniqu A fractionsDN e .

GENERAL DISCUSSIO CONCLUSIOND AN N S e evidencTh e collecte e affinitieth n o d s among species indicate tha o uniqun t e grouping with evolutionary significance cae basie traceb nth f separato n so d e criteri f affinitieso a . The reason r thifo ss r resideopinione facou th n ts i i ,tha , t whenever affinities have been foune informatioth d n stemmed fro narroa m w genetic background.

226 As ci matter of fact the reviewed literature showed that, except for cytological affinities, evolutionary trends were postulate w proteine basife th f r threo o n so dso ecodetw y b d A segmentDN genesn o sr o , (rDNA genes) that covered less tha% 1 n of the total genomic DNA. However cytogenetical data are often contradictory depending on the strain used for a certain species in the hybridization process to study chromosomal homoeology or in comparing C-banding patterns. This causeha s d different authors ^c reach contradictory conclusione th affinitie n o s s relationship among Triticinae. In or d r to avoid inconsistency, all that is required is a method for recognizing homology and eliminating analogy. Goul ) indicate(1 d ! tha mose ttn t promising too o searct l h f DNA-DNo e us r homolog Afo e hybridizationth s i y . Thi becauss si e th e unique sequenc A differDN f o e s from morpholog n jusi y t those properties that capture homology. DNA is complex enough to preclude analog a caus s f overala o ey l similarity. DNA-DNA hybridization work n findini s g similarit o reasontw r f o fo sy mathematical probability its matches are too complex to evolve independently, and its sample size (all nucleotides of all single-copy DNA) is so large that any superficial analogy may be shaded by similarity of shared descent. Using DNA-DNA hybridization phylogenies in Triticinae can be deduced completely independently from morphology and cytogenetics and the affinities of species such as D.villosum to the cultivated Triticinae can be evaluated on a secure base. Probably one result of such study will be that the apparent divergenc f D.villosuo e m from other Triticina s lesi e s thae th n real genetic distance deducee overalth A t levela dDN l .

REFERPNO'

M i SOULD, S.J., A clock of evolution, Natural History 4 f198b). (2} KIHARA, H., Cytologische und genetische Studien bei wichtigen getreidearten mit besanderer rucksicht auf- das verhalten der Chromosomen und die Sterilität in den bastarden, Me-i, Coll. Sei. Kyoto Imp. Univ. Sez. B l (1924) 1. (3l KIHARA, H., Interspecific relationship in Tnticum and Aegilops, Seiken Ziho 15 (1963) l. M) KIHARA, H., Die entdeckung der DD-analysatoren beim Weizen. Agric Hortic., Tokyo 19 (1944) 889. (5) OKAMOTO, M., Asynaptic effect of chromosome V, Wheath Inf. Serv 5 (1957. . )6 (6) DRISCOLL, C.J., Genetic suppression of homoeologous chromosome pairing in hexaploid wheat, Can. J. Genet. Cytol. 14 (1972) 39. ) UPADHYA(7 , M.D., SWAMINATHAN, M.S., Mechanism regulating chromosome pairing in Triticum, Biol. Zentrolhl (Suppl.) 86 (1967) 239. ) C M DVORAK(8 GUIRE , I ,, P.E., Nonstructural chromosome different afion a-^ong wheat cul^ivars, with special reference to differentiatio f chromosomo n n relatei e d specieE), Genetics 7 '19819 ) 391. ) GILL(9 , B.S., KIMBER , GiemsG. , a C-bandin e evolutioth d an g n of wheat, Proc. Natl Acad. Sei. U.S 1 (19747 . ) 4086. (10) TEOH, S.B., Interspecific variation in C-banded chromosomes of diploid Aegilops species, Theor. Appl. Genet. 65 (1983. )31 (11) MAIRE, R., Flore de l'Afrique du Nord (LECHEVALIER, P.), Paris (1952). (12) SASAMUKA , MAANT. , , S.S., Male sterility-fertility restoration system n Triticui s m durum, Can . GenJ . . Cytol0 2 . (1978^ 389 (13) JAASKA, V , Alcohol dehydrogenase of polyploid wheats on their diploid relations in the phylogenesis of tetraploids cheats, Genetik 1 (19761 2 . 1 a) 22 (14) uAASKA, V , Aspartate aminotransferase isoenzymes of poliploid wheat d theian s r diploid relatives e origith f n o O n. tetraploids wheats, Biochem Physiol. Pflanzen 170 (1976) 159. (15) JAASKA, V., Electrophoretic survey of seedling estera,es in wheat n relatioi s o theit n r phylogeny, Theor Appl Genet. 56 (1980) 273. (16) KASARDA, D.D., LAFIANDRA, D., MORRIS, R , SHLWRY, P R., Genetic relationship f wheao s t gliadin proteins, Kultuipflanze 32 (19843 )3 (17) PAYNE, P.I., HOLT, L.M., LAW, C.N., Structurad an l genetical studies on the high-molecular-weight subunits of wheat glutenin, Theor. Appl. Genet. 60 (1981) 229. (18) COLE, E.W., FULLINGTON, J.G., KASARDA, D.D., Grain protein variability among specie f o Triticus d an Aegilopm s quantitative SDS-page studies, Theor. Appl.Genet 60 (1981) 17. (19) MONTEBOVE, L., Studio delle caratteristi ehe gemticht t

morfologiche di anfiploidi Triticum x Dasypyrurr , B3d Thesis Universit f Tusciao y , Viterbo (1985). (20) HART, G.E., Evidenc r triplicatfo e e gene r alcohofo s l dehydrogenase in hexaploid wheat, Proc. Nat Acad. Sei (56 4 (1970) 1136. (21) HART, G.E., "Glutamate oxaloacetate transaminase ibozymes f o Triticum evidenc r multiplfo e e system f o triplicats e structural gene n hexaploii s d wheat", Isozymes III, Academic Press, Inc Yorw Ne .k (1975). (22) AINSWORTH, C.C., GALE, M.D., BAIRD, S., The control of grain esterase n hexaploii s d wheat, Theor. Appl. Genet8 6 . (1984) 219.

228 (23) PAYNE, P.I., HOLT, L.M., JACKSON, E.A., LAW, C.N., Wheat storage proteins: their genetics and their potential for manipulation by plant breeding, Phil. Trans. R. Soc. Lond. (1983). (24) DVORA . SCHELTGEJ K N E..Phylogenetic relationsnips among DNAs of wheat, rye and Agropyron, Proc. 4th Internat Wheat Genetics Symposium Missouri Agr. Exp. Sta., Columbiao M , (1973). (25) NATH, J., THOMPSON, J.P., GULATI, S.C., Identification of e G-genomth e dono o t Triticur m timopheev y b DNA-DNi A Hybridizations, Biochem. Genet. 23 1/2 (1985).

229 AGRONOMIC EVALUATIO INDUCEF NO D SEMI-DWARF MUTANT DURUN SI COMMOD MAN N WHEAT*

C MOSCONI . GIORGB , I Divisione Tecnologie Biologich Agranee , ENEA-FARE, CasacciaE CR , Rome, Italy

Abstract

e duruTh m wheat cultivar "Anhinga o cultivartw d an "f o s common wheat "Anza" and"N. Strampelli" were irradiated with fast neutrons to induce short straw mutants with greater lodging resis- tancd yielan e d potential. From a total of about 4,000 irradiated seeds 1,^02 M plants were harvested. These gave rise to a population of about 25,00 0M plant s among which 1,010 plants were isolate s potentiaa d l mutants showing promising agronomic characters. Following progeny tests and selection 280 true-breeaing mutants entered preliminary yield trials. After several years of testing only two lines one of duruf commoo e m on nwhea whead an t t showe a highed r yiel- po d tential than the control varieties. In particular the durum wheat mutan 027M (F t ) afte year7 r f fielo s d trials spread ove 0 selec1 r - ted places, outyielde . "Cresocv e th "d (the leading variet n Ceni y - tral Italy) by about 13.6%. The mutant fD 14 from Anza after 5 years of testing in 8 locations, performed on the average better than the mother variety and outyielded the standard cv. "Orso" by 12.1%. Thes o linetw e s have been submitte r registratiofo d e th n i n National Registe f Varietieso r . Other mutant e beinar s g user fo d cross-breeding.

Introduction

Mutation breedin s beeha g n relatively easd quitan y e

effectiv cerealsn i e , especiall e inductioth r fo yf shorno t strav.

mutants capabl f improvino e g lodging resistance mutageme Th . c approac n durui h m wheat breeding starte t Casaccia d a Nuclear Center e 1950'sth f o , d proveen e verb e o yt th d successfut a . Fou2) r, (I l

" Contribution no. 119 of the Divisione Tecnologie Biologicht o Agrane , ENEA.

231 short straw mutants were release w cultivarne s a d year1 1 s s after

radiation treatment (3).

Other varieties such as Creso, Mida, Tito and Augusto were the

resul f indirec o tf mutant o e us ts through cross-breedin. 5) , (4 g

In common wheat the search for lodging resistant mutants

was discouraged due to the availability of semi-dwarf varieties carrying

dwarfing genes from Japanese wheat germ-plasm.

The introduction of new genotypes from International Agricul-

ture Research Centre, such as CIMMYT, offered the possibility of their

direct use in Italian conditions because of their wide adaptability.

However, very often minor phenotypic adjustments were necessary to meet

the farmer's needs. This was the case of the wellknown cv. Anza widely

cultivate Californin i d amann i (USA yd othean ) r countries. Suc a varh -

iety was tested in Italy since the early 70's, proving to be high

yieldin t moderatlbu g y susceptibl o lodgint e g becauss planit tf o e

w centimeterheighfe a t s ovee normalth r A simila. r situatio s founwa n d

. StrampelliN . cv wite th h, obtained froe crosth m s Liber x o(S.Pastor e

x Jacomett) 49 i

In durum wheat, a variety with good agronomic traits named

Anhinga proved to be too tall in field experiments and then highly

susceptibl o lodgin t er suc Fo h. g reasons envisagewa t i s o start d a t

mutation breeding programme in the early 1970's with the main aim of

inducing suitable short straw types.

Materials and Methods

Seeds of the cultivars Anhinga, N. Strampelli and Anza were

subjected to a mutagenic experiment with fast neutrons by applying

a total dose of 3 Krad. The radiation treatments were carried out at

the Casaccia Nuclear Reactor "Triga n 197 i "r Anhing . 1fo N d an a Strampell n 197i r Anza d 4fo e thousanan i On . d seeds were irradiated e firs o varietieth r eac tw tfo f o he third th d 2,00e irra an sr Th .0 fo - diated seeds wer e fiel th sow dn i n along wit comparabla h e number f unirradiateo d seeds take s controlsa n .M plant s were individually

232 harvested and classified according to the number of spikes per plant

and to the fertility per spike (when only one culm was present).

From eac M hplan numbea t f seedo r s varyin 5 wer2 g o efrot sow1 m n r scorinfo g variants e plantTh . s that appeared promising froe th m

agronomic point of view were progeny tested and moved to the next

generation for further analyses and observations.

Selection based on the pedigree method was practiced up

to an acceptable level of uniformity and stability.

Startin ge mutan th fro M mt lines were teste n prelimii d - nary agronomic trials based on a single row 5 m and 30 cm apart, replicate o timestw d n somI . e cases, particularl n commoi y n wheat, mutated plants isolate M wern i de subjecte o selectiot dM o t p u n ^ -L O to attai sufficiena n t exten f uniformityo t . 2 The most promising lines were subsequently tested in 10 m plots followin randomizea g d complete block design wit replica3 h - tions. Depending on the results obtained and the amount of seed available,multilocation field trials were carried out in 8 - 10 places disseminate e centrath n i dl par f Ital o td repeate an y r fo d 5-7 years. Special attentio s focusewa n n plano d t height, lodging

resistance, disease resistance, test weight and yield.

Result Discussiod an s n

Durum wheat

M plants A8 tota54 f ,o l correspondin seede th sf o survivaa % o t g55 f o l irradiated were harvested ( Table 1 ). In M 513 plants out of 8,447 M seeds sown were isolated as probable mutation carriers. As expected, the number of mutants increased parallel to the higher leve f damago l e estimate e basith f tilleo sn o d r numbe d seedan r pe s spik Tabl( . ) e 2 e The mutation frequenc s 6.0numbee wa y. baseM th 7 % seed f n o ro d s sown, which shows the high efficiency of the treatment especially if one considers that the visibly useless plants were omitted.

233 Table 1. Data related to the materials and methods used for mutagenic experiments with fast neutrons.

Cultivars Yeaf o r Dose Nof seedo . s Percentage No. of Ml irradia- applied irradiated of plants tion (Krad) germination harvested

Durum wheat

ANHINGA 1971 3 1000 55 548

Common wheat

STRANPELLI 1971 3 1000 65 431

ANZA 1973 3 2000 45 723

Table 2. Frequencies of short straw mutated plants of cultivar Anhinga (T. durum) according to the number of spikes r plan pe d fertilityan t .

M plants M No f .f o o . No No. of No. of fo . No Frequency sub— group spikes plants M seeds M seeds putative of mutated per from each sown mutants plants in

plant M plant selected M2 (%)

Sg 1 4 54 25 1,350 48 3.5 Sg 2 3 137 20 2,740 148 5.4

Sg 3 2 203 15 3,045 216 7.1

Sg 4 I3 110 10 1,100 79 7.2 Sg 5 lb 9 AL1, 72 9 12.5

Sg 6 1C 35 ALL 140 13 9.J

TOTAL 548 0,44/ 513 6.07

a. With 10 or more seeds b. Wit 9 seedh8- s c. With less tha seed8 n s

234 Startin9 mutan,9 M t g o linet fro M sm were entered into preliminary field trial Tabl( s. ) Fro 3 em fiftee nM line mutansa t line 6 s isolatedwa 7 F02 M .

Table 3. Number of mutant lines isolated in different generations and tested for the first time in agronomic trials for yield performance.

GENERATION ANHINCA ANZA STRAMPELLI

M4 42 M5 27

M6 15* GO* 3 M7 7 49 12*

M8 1 33 1

H9 3 2

MIO 4

TOTAL 99 142 18

The best lines have been selected in these entries.

After several field tests it was decided to submit it to the Variety Register Offic r inclusiofo e n witNationae th h l Registe f Varieo r - ties . FM 027 is 20 cm shorter than the mother variety Anhinga and has

erect leaves. After 7 years of field trials in 10 selected sites it outyielded the cv. Creso ( the leading variety in Central Italy ) by 13.6 %. day6 - s 4 earlies Ii t r thatallerm c n0 1 Cres Tabl.( . d ) an o4 e The quality of FM 027 though acceptable is lower than that of Creso based on test weight and percentage of yellow berry.

235 Tabl . 4 e Performanc a duru f o em wheat mutant line FM027 (from . Anhingacv ) teste0 place1 n i f Centrado s l Italr fo y 7 years. (Mean4 agronomi3 f o s c trials).

CULTIVARS PLANT LODGING EAR EMER- YIELD TEST YELLOW-

HEIGHT INDEX GENCE DATE q/ha WEIGHT BERRY cm (0-5) kg/hi %

FM02/« Ob. y 0. 7 MAY 5.9 60.9 80.0 12.2

CRESO 76.9 0.3 MAY 11.2 56.1 81.6 5.0

VALNOVA 89. 1 1.1 MAY 7.0 53.6 78.1 7.8

* To be released as ICARO

Table 5. Frequencies of short straw mutated plants of common wheat cultivar Strampelli, according to the number of spike r plan d pe sfertility an t .

M plants No. of No. of No. of M seeds No. of Frequency

subgroup spikes M plants M seeds sown putative of per from each mutants mutated plant M plant selected plants in

M2 (%)

Sg 1 4 33 ?5 825 28 3.39 Sg 2 3 85 20 1,700 52 3.06 Sg 3 2 143 15 2,145 82 j.82

Sg 4 I3 170 10 1,700 82 4.82 b bg 5 51 ALL 300 22 7.33

TOTAL 431 G.G70 2G6 4.00

a. With 10 or more seeds b. with less tha 0 seed1 n s

236 Common wheat

The frequency of survival was lower for common wheat than for durum

. StrampelliN . cv M variante wheat6 th 26 , r .Fo s were identified from

6,670 M seeds sown. Here again a positive relationship between overall plant damag d frequencan e f plano y t variants seeme o occut d r (Tabl. 5) e Progeny test sM carrien confirmei t ou d d putae thath t-f o 86. % 8 J tive mutants identifie M n weri d e short mutante th sn I (Tabl . ) 6 e following generations a totastartin lM numbe 9 o g3 t frof o r M m

mutants were entere preliminarn i d y agronomic trialo s Tw (Tabl . ) e3

shor 1 showet12 stra t slightla dS d w an mutants 6 y 11 highe t S , r yield

and improved lodging resistance than the mother variety (Table 7 ).

However.after further s trialdecidewa t o i stose t effort d th p s

aimed at their direct utilization and try instead to use t ht-T, for

cross-breeding.

Table 6. Progeny test in M„ of short straw mutants of common wheat cultivar Strampelli

M plants No. of No. of No. of M seeds MS proge Percenta- subgroup spikes M M seeds sown nies - comu n f go e 2 per mutated from each firming tations plant plants M plant muta- confirmed

tions inM3

Sg 1 4 28 11 308 22 78.6 Sg 2 3 52 11 572 46 88.5

Sg 3 2 82 11 902 78 95.1

Sg 4 I3 82 11 902 69 84.1 b Sg 5 22 11 242 16 72.7

TOTAL 266 2.929 231 86.8

r mor o . Wit a 0 e1 h seeds b. with less tha 0 seed1 n s

237 Table 7 Performance of two common wheat mutant lines St 116 and St 121 (from cv. Strampelli) tested in 7 places of Central 1 yeaItal r r fo y(Mean 7 agronomi f o s c trials)

PLANT LODGING EAR YIELD TEST WEIGHT

CULTIVARS HEIGHT INDEX EMERGENCE q/ha kg/hi

cm (0-5) DATE

St 116 92.1 2.5 MAY 2.0 58.7 79.1

1 S12 t 83.9 1.6 6 MA4. Y 57.9 77.8

STRAMPELLI 100.1 3.5 0 MA2. Y 5b.6 80.3

These mutant e beinar s g user crosfo d s breeding.

The mutagenic approach applied to the cv. Anza was more successful. From more than 10,000 M plants 400 agronomically valuable variants were

selecte e nex d taketh an t do t generationn . Further selectio s carriewa n d a singl n o et planou . Startin M t o basit ga totap u sfro f o lM m 13 6 142 mutants were tested in preliminary agronomic trials to evaluate

the yield potentia Tabl( l. ) Despit 3 e e severth e e selection pressure

applied , shortemutane 14 th , D f tr than Anz y aboub a t 8-1 afte, cm 0 r

year5 f testino s 8 location n i g Centran i s l Ital ygooa provee db o t d

yielding line t onl no n ,comparisoi y n witmothee th h r variety Anzt bu a also with an outstanding variety named "Orso" (Table 8). In 21 agronomic trial mutane 4 outyielde1 th s D f t d Ors y 12.1%b o , showe beta d - ter lodging resistance highea , r test weigh d flowerean t 5 day4- ds

earlier (Table 8). Since fD 14 was tested in a wide range of climatic

condition n differeni d an s t agrotechnique regime appeart i s s tnis geno-

typs widha e e adaptation. Other noteworth- mo e y ar character 4 1 D f f o s

derate disease resistance, slender culms, short narro d erecan w t flag

leaf, small but highly fertile spikes and average seed weight. These

yield component e suitabl ar sa dens r efo e stan possibls y whici b d t i h e 2 higa t ht ge onumbe . f spikem o r r pe s

238 Table 8. Performance of a common wheat mutant line fD14 (from cv. ANZA) tested in 8 places of Central Italy for 5 years (Mean1 agronomi2 f o s c trials).

PLANT LODGING EAR YIELD TEST WEIGHT CULTIVARS HEIGHT INDEX EMERGENCE q/ha kg/hi

cm (0-5) DATE fi)14» 81.4 0.1 MAY 2.8 71.1 8O.O

ANZA 88.3 0.6 3 MA3. Y 69.9 79.9

ORSO 87.6 1.2 MAY 7.6 63.4 78.5

releasee b o T SPINNAKEa • a d R

In conclusion, mutation breeding aimed at improving existing varietie y reducinb s g plant heigh trealistia seeme b o t s c goal with a relatively short development time and moderate costs.

Acknowledgement

The author e greatlar s y indebte Profo t d . ULLRIC.S H for critical reading of the manuscript.

REFERENCES

) SCARASCIA-MUGNOZZ(1 G.T.. A , BAGNAR BOZZIN, . D Mutation" A . A I s induced in durum wheat and their significance in genetic breedind san Proc" g Whead .3r t Genetics Symp. (FINLAY K.W., SHEPHERD K.W. Eds.) Plenum Press, New York (1968). ) BAGNAR(2 . ResultD A d Perspectivean s Mutagenesif so s applieo t d durum wheat. CNEN, RT/PROT (1975. )11 (3) GIORGI B., MOSCONI C. Short straw mutants and other dwarfing gene source e improvemensth user fo d Wheatf o t d Barlean s y in Italy Researct 1s .e Procth h f Coordinatio.o n Meeting on " Semi-dwarf Cereal Mutants and their Use in Cross - Breedin IAE" g TECDO- A8 (1982 26 - C) 53-58.

239 ) BOZZIN(4 MOSCON, A. I . CresC Ia nuov un o a variet i frumentd à o duro caratterizzata da interessanti prestaziom agrono- miche, Genetica Agraria 30 (1976) 153-162.

(5) BOZZINI A., BAGNARA D. Creso, Mida e Tito, nuovi gram duri dalle eccellenti prestaziom, L ' informatore Agrario n.35 (1974) 20347-20354.

240 SEMI-DWARF MUTANTS AND HETEROSIS IN BARLEY . Interaction// between several mutant genes responsibler fo dwarfism in barley

I. SZAREJKO*, M. MALUSZYNSKI**, M. NAWROT*, B. SKAWINSKA-ZYDRON* * Department of Genetics, University of Silesia, Katowice, Poland ** Plant Breeding and Genetics Section, Joint FAO/IAEA Division, International Atomic Energy Agency, Vienna

Abstract

Dwar d semi-dwaran f f mutants obtained after mutagenic treatment were chosen as material for genetic investigation of this character. A non- allelic relationship was found among six analysed mutants. The interactio s observewa n d betwee l analyseal n d genes responsiblr fo e dwarfness, including uz and br genes. It was demonstrated that expression and interactio f o dwarfinn g genes strongl ye genetith depen n o cd background of recombinants.

Morphologica w characterslfe mutanta f o s, obtaine n i varioud s laboratories after mutagenic treatmen f differeno t t barley varieties, were genetically investigated in detail. The following types of mutants have been analysed very thoroughly: eceriferum forms (Lundqvisn vo d an t Wettstein, 1962; Lundqvis t e al.t , 1968), chlorophyll mutants (von Wettstei d Kristiansenan n , 1973) r morphologea , y mutant s erectoidea s s (Persson and Hagberg, 1969; Persson, 1969a,b), breviaristatum (Kucera, 1975; Kucera et al., 1975), hexastichon and intermedium (Fukuyama et al., 1972; Fukuyam t al.e a , 1975; Gustafsso d Lundqvistan n , 1980), laxatum (Larsson, 1985a,b) n organizeI . d mutant germ-plasm collections, froa m few up to several dozen different loci were found and localized on barley chromosomes for each group of mutants.

Dward semi-dwaran f f barley mutant o s sintensivel t werno e y investigated e .barle th Nonf o y e genetics centers have organized collections of dwarf or semi-dwarf mutants similar to the collections of ecerifrum, erectoides or chlorophyll stocks. Short stature barley mutants wer t n choseobjectiva no e s a n r broadfo e , basic genetic investigations. e verTh y high frequenc f dwaro yd semi-dwaran f f mutants obtainee th n i d Department of Genetics, Katowice after MNH treatment of different spring barley varieties (Maluszynski, 1982; Maluszynsk t e al.i , 1987)s ha , provided an opportunity for genetic analysis of this character.

241 Material and Methods

Nine short stature spring barley (Hordeum vulgär . L convare . distichon /L./ Alef.,) mutants were chosen for investigation from more than 300 dwarf and semi-dwarf mutants existing in the collection of the Departmen f Geneticso t , Katowice. Mutants were obtained from five barley varieties cultivated in Poland at this time. The following true breeding g stockprogenyM f o s , after mutagenic treatmen f MNHo t , were user fo d genetic analysis: K froA m8 variet64 y Aramir K froP m2 variet86 y Plena K froM 0 m 27 variet d an 26g 417K M y7M 0 392 JK and 409 from variety Julia K froD m8 variet63 d an yK D Delis 5 55 a, DK 8 53

Three of these mutants (270 MK, 538 DK and 638 DK) indicated non- monogenic inheritance of the sd-character in $2 progeny of crosses with parent varieties A detaile. d descriptio f theso n e mutant d resultan s f o s the genetic analysie remaindeth f o s r were presente y Szarejkb d o (1982) and Szarejk d Maluszynskan o i (1984a,b). Brachytiu mutantuz d an sc with gene r frob s m chromosomz fro u md chromosoman 1 e wer3 e e used additionally e stud th f interactio o yr fo n among different semi-dwar r dwaro f f mutant genes.

I progenieF e Th s were plante a greenhous n i d e durin e winteth g r o r n experimentaa n i sprin3 F d gan l seasonfield2 F e .th ,

Result d Discussioan s n

A non-allelic relationship was found among analysed mutants from our collectio f markeo n ncontrastI ^ (TablF r. e 1) stoceth , k brachytic with K reachemutanA 8 64 & theighd t similae parenth o tt r carryinr b e th g locus. Both forms, mutant 648 AK and stock brachytic, expressed a similar phenotyp n boti e h greenhous d fielan e d conditions n thesI . e experiments the mutant 648 AK was always about 10 cm shorter. The genetic analysis confirme e localizatioth d f e botsamo nf th theo e hn i locum s (Szarejkd an o Maluszynski, 1984a). We did not find an allelic relationship between other mutant marked an s r stocks brachyti r uzuo c .

Dwarf double recombinants were found in F2 progenies of all crosses between non-allelic mutants. The height of recombinant plants was dependent on the interaction of two genes responsible for dwarf or semi-dwarf character of parental mutants. The next (F^) progeny of self-pollinated recombinants indicated their homozygosity.

The interaction was observed between all genes responsible for dwarfness, which effecte e phenotypth d f doublo e e recessive recombinants e recombinantTh (Fig . 1) . s were alway s mucs a s 40%) a shorteho t ,p (u r than the dwarf parental mutant. The highest effect of interaction was observed between gene uz and genes of dwarf mutants 392 JK and 555 DK. In these cases, double recessive recombinants where extremely short and never exceeded 20-21 cm. The interaction of genes responsible for semi-dwarf height of mutants 862 PK and 267 MK was much smaller. The expression of both these genes gave plants only m shorteabouc 0 1 t r thae mutantsth n .

242 Tabl : 1 e Result f complementatioo s n test (F^) between investigated dwar r semi-dwaro f f mutants (greenhouse)

Cross HeighI plantF f o t+ s SD combination (cm) winter season spring season

648 K AJ K X2 39 66.6 + 3.1 648 K AJ K X9 40 63.1 + 7 .0 648 AK X 55K D 5 66.4 ± 6.3 862 PK KM X7 26 74.5 + 8.1 862 PK X 409 JK 66. 7 + 7 .6 862 PK X 55K D 5 71.2 + 7.2 267 MK X 392 JK 79 .8 + 3.6 267 MK X 409 JK 70. 7 + 10 .3 267 MK X 55K D 5 68.7 + 4.1 392 K JP K X2 86 79.0 + 4.2 392 K JJ K X9 40 75 .8 ± 2.5 409 JK X 555 DK 65.0 + 4.0 555 DK X 392 JK 63.7 + 4.9

648 AK X br 63 •5 ± 5.2 862 PK X br 59.4 + 10 .1 267 MK X br 79.o ± 7.0 392 JK X k£ 78 .9 + 7.1 409 JK X br 65.o ± 5.9 555 DK X br 61. 7 + 10 .4 648 AK X uz 57.9 ± 5.6 862 PK X uz 76 .7 + 8.3 267 MK X uz 78 .2 ± 3.8 392 JK X uz 61.5 + 4.9 409 JK X uz 77 .6 ± 4.5 555 DK X uz 63.o ± 5 .7

mutants : 648 AK 39.8 + 4.9 48 .0 + 4.3 K P 2 86 52.8 + 5 .2 69 .2 ± 7.0 267 MK 56. 7 + 6.8 73 .2 ± 2.6 K J 2 39 41.2 + 3.0 50 .0 + 4.1 409 JK 47.0 + 6.8 60 •1 ± 3.0 55K D 5 41.8 + 3.6 46 •1 ± 2.4 brachytic 48.o ± 4.0 59 •2 ± 6.4 uzu 46.0 + 10 .1 63 .5 + 3.8

243 cm 648 AK 002 KK -^O/MIV J9^JI\ 40 4 M•h il, rt •îj T r T 36 L t ± rî- Î fi * f tl i-rf fi 20 |fj *1 *1 -T Pl 10 ex. t-- Q CO CM •*• vn i—i M « e c a 4 A K «^ O e c ^ 11c c o mutants recombinants cm K D 5 55 40 K J 9 40 br uz

30 -T1 T i- T 1 pt-i"il -^* L r '*t- A il L v - 20 T ^ •{• T" -t 1^1 n-il•£ 10 123467 123 4 578 23 56 i4 6 recombinants i— cross with mutant 648AK 5— cross with mutant 409JK K P — 2 2 86 —II— D5 K55 — l —i — 6

K J 2 39 — l —i — 6

e heighTh f Figdoubl o . t 1 . e recessive recombinants from crosses between dwarfing mutants

In our experiments, similar to results published by Konishi (1977), the expression of dwarfing genes and their interaction depended considerably e genetith n o c backgroun f recombinantso d r exampleFo . e heighth , f o t double recessive recombinants with the gene responsible for dwarfness of mutant 555 DK varied in different crosses from 59.5% to 81.6% in comparison to particular parent forms (Table 2).

e heighTh f doublo t Tabl e: 2 erecessiv e recombinants a s a result of the interaction of mutant 555 DK gene with other dwarfing genes

Cross Heigh f recombinanto t n i s combination relatio o secont n d parent

555 DK x 648 AK 81 .6 tl x 862 PK 74 .5 fl X 409 JK 70 .3 tl X 267 MK 64 .0 t* X uzu 62 .1 ft X 392 JK 61 .1 It X brachytic 59 .5

244 The number of internodes of analysed double recombinants was usually e similaparenth o t r forms. Only recombinantK M e mutan th 7 f 26 o ts inherited, in all crosses, the higher number of internodes (from 79), as e leafth wel ys e a collalbrac th n i tr region, which e mutantypicath r tfo l phenotype. Similarly, the pleiotropic effect of dwarfing genes uz and b_r s expresse wa l theial n ri d recombinants. Double recessive recombinants wit z genu h e were alway f o semi-prostrats e growth type: short, broad leaves; extremely short flag-leaf; very dense ear inside a flag leaf sheath with drastically shortened awns. Recombinants with gen r greb e w erect, had dark-green leaves and rather long spike with short awns. The pleiotropic effec K (lighf mutanP o t 2 t86 t green rosette s expressewa ) n i d all recombinants of this mutant.

The fertility and vitality of recombinants with two dwarfing genes was often decreased in comparison to the parents. A high level of sterilit s alwaywa y sl recombinant noteal n i d s with gen. uz e

A limited number of extremely short plants (from 12 18 cm.) was observed in the F2 progenies of several crosses with mutants 862 PK, 409 JK and 555 DK. These segregants very often died in the rosette stage and were always sterile. The normal double recombinants were observed parallel to these forms.

The interaction of genes br and uz^ in double recesive forms was noted by Leonard et al. (1956) as well as Takahashi and Hayashi (1956). The effect of interaction between these genes, reported by the authors, was much bigger than observe r experimentsou n i d . Double recombinant, uz r bj s as reporte y Takahashb d d Hayashian i , reached only e mutant20-25th f o % s height while the same recombinants with "Aramir brachytic allel" reached about 70% of the height of both mutants. It should be noted that in our experiments the interaction effect between these genes was observed in relation to the length of culm and spike of recombinants but not to the lengt f awnso e hvariou Th . s expressio f differeno n t alleles from locr b i r extremelo z u d yan different genetic backgroun f investigateo d d mutants as well as climatic conditions could effect unlike interaction of these r experimentso genesou tw n i e pas,d th bot an tn i h.

REFERENCES

FUKUYAMA, T., HAYASHI, J., MORIYA, I., TAKAHASHI, R. , (1972) A test for allelism of 32 induced six-rowed mutants. Barley Genetics Newsletter 2: 25-27.

FUKUYAMA , HAYASHI,T. TAKAHASHI, ,J. , (1975. ,R ) Geneti d linkagan c e studies of the five types of induced 'six-row' mutants. Barley Genetics Newsletter 5_: 12-13.

GUSTAFSSON LUNDQVIST, ,A. , (1980. U , ) Hexasticho intermediud an n m mutant barleyn i s . Heredita : 229-23692 s .

KONISHI , (1977,T. ) StudieS induceEM n o s d mutation barleyn i s . VI . Interactions among several dwarf mutant genes. Nogaku Kenkyu 56: 155-166.

KUCERA, J., (1975) Pleiotropic effect and complexity of some breviaristatum loci. Barley Genetics III. Proc. Third Intern. Barley Genet. Symp., München: 164-170.

245 KUCERA LUNDQV1ST, J. ,d GUSTAFSSON an , ,U. , (1975,A. ) Inductiof o n breviaristatum mutants in barley. Hereditas 80: 263-278.

LARSSON, H. E. B., (1985a) Genetic analysis of laxatum barley mutants. Hereditas 103: 255-267.

LARSSON, H. E. B., (1985b) Linkage studies with genetic markers and some laxatum barley mutants. Hereditas 103: 269-279.

LEONARD, W. H., ROBERTSON, D. W. , MANN, H. 0., (1956) Complementary factors for height inheritance in barley. Japan. J. Genet. 31; 229-240.

LUNDQV1ST WETTSTEINn vo , , U. , (1962,D. ) Inductio eceriferuf o n m mutants in barle y ionizinb y g radiation d chemicaan s l mutagenes . I .Heredita s : 342-36048 .

LUNDQVLST, U., von WETTSTEIN KNOWLES, P., von WETTSTEIN, D., (1968) Inductio f eceriferuo n m mutant n barlei s y ionizinb y g radiationd an s chemical mutagenes. II. Hereditas 59: 473-504.

MALUSZYNSK1, M., (1982) The high mutagenic effectiveness of MNUA in inducing a diversity of dwarf and semi-dwarf forms of spring barley. Acta Soc. Bot. Pol : 429-440.51 .

MALUSZYNSK1 SZAREJKO, . ,M , MADAJEWSKII. , FUGLEWICZ, . ,R d an . ,A KUCHARSKA (1987, . ,M ) Semi-dwarf mutant d heterosian s barleyn i s . I . f barleo e yus e sd-mutantTh r hybrifo s d breeding. TECDOC, IAEA, Vienna, (in press).

PERSSON , (1969a,G. n attempA ) o fint t d suitable genetic markerr fo s dense ear loci in barley. I. Hereditas 62: 25-96.

PERSSON , (1969b,G. n attempA ) o fint t d suitable genetic markerr fo s dense ear loci in barley. II. Hereditas 63: 1-28.

PERSSON HAGBERG, ,G. , (1969A. , ) Induced variatio quantitativa n i n e character in barley: Morphology and cytogenetics of erectoides mutants. Heredita : 115-17861 s .

SZAREJKO , (1982I. , ) Dziedziezenie cechy karlowatosc wybranycu i h mutantow jeczmienia jarego. Ph.D. Thesis, University of Silesia, Katowice.

SZAREJKO, I., MALUSZYNSK1, M., (1984a) New brachytic mutant of spring barley variety Aramir. Barley Genetics Newslette : 33-3514 r .

SZAREJKO MALUSZYNSKI, I. , , dwarw (1984b, M. ne gene m f o is n barleo sTw ) y chromosom . 3 Barlee y Genetics Newslette : 35-3814 r .

TAKAHASH1 HAYASHI, ,R. , (1956J. , ) Genetic studie f barleo s y crosses involving two brachytic genes. Japan. J. Genet. 31: 250-258.

WETTSTEIN von, ,D. , KRISTIANSEN , (1973K. , ) Stock lisnuclear fo t r gene mutants affectin chloroplaste th g . Barley Genetics Newslette : 113-1173 r .

246 MUTANE RY DWARFINEFFEC1 E TEM TH F TO G GEN OCTON EHEXAPLOIO D AN - D TRITICALE Preliminary report

T. WOLSKI, E. TYMIENIECKA Laski Plant Breeding Station, Laski, Poland

Abstract

Preliminary results presented show a strong influence of the EM1 rye dwarfing gene on plant height of octoploid triticale and on F2 hexaploid cross progenies. The possible use of this source in triticale breeding is briefly discussed.

In the Poznanska Hodowla Roslin Station's winter wheat programme crosses with semi-dwarfs from different sources were used. Among them was the dwarf mutant Bezostaya, which contrary to material based on Norin 10 t givdino dy epromisin an ris o t e g advanced line.

In the rye programme the EMl mutant of Kobylyanskii II] semi-dominant for the dwarf character was used and this type has been much improved in plant type, yield and resistance to diseases. It proved, however, impossible to fix the semi-dwarf type as much taller plants always segregate a resul s f a o distandt t open pollinatio d soman n e back mutations. A characteristic of this material is presented in Table 1.

The idea of using short rye to produce short triticale was initiated by CIMMYT breeder e improvee strainth ry s f l [2]o EM s d e .L506On s ?wa 9 useTarkowskby d co-workersand i to produc* e octoploid triticalein s combination with several wheat varieties and lines. Some other octoploids were obtained from crosse f shoro s t wheats wit a talhe strai ry l n Mil. Selected octoploids were crosse n hexaploidow r witou hd triticale material ^ obtaineF .e th Som df o eseeme d very promising, being short, lodging resistant, fertile, uniform and having plump kernels. The F2 progenies were strongly selected for hexaploid plant type, fertility and plump grain.

Tabl 2 showe e planth s t heigh f fouo t r octoploid s comparea s o t d their parents of the F2 selected hexaploid plants. As seen, the EMl dwarfing gene exercise a strons g shortening effec n o hybridst d an , transgressive forms are obtained. When the wheat parent is a semi dwarf itself, extremely short ocotoploid material is obtained, so that not much success in crossing to hexaploids may be expected. When a short wheat was crossen intermediata a tale o ry lt d e tritical s obtainedwa e .

* personal communication . Tarkowski:Cz , Departmen Planf o t t Breeding, Agricultural University, Lublin, Poland

247 Tabl . 1 eCharacteristi e improveth f 1 semi-dwaro c EM d e materiary f l as compared to the tall standard Dankowskie Zlote (Laski, 1983)

* — — i — i— —— -i i------1—— —1 - r —————— i [Grain 10GO Test [Plant Lodpin? Va r j ety- strain yield prain weifft hh t? i ihe resistan- t/ha weipht Vff/h'l [cm . p cQ e er score Q- best ------...... L506~g-s-dwarf 5.7 30 72 120 9. U

Dankowskie Ziote 6.2 JO 7^ 16C 7.8 /tall standard/ .....J _____ J. ————— .1

Table 2. P]ant height of 4 octoploid triticale strains as compared to their wheat and rye parents and the same character in respective F2 octo-hexa hybrids (Laski, 1985).

! Plant height in cm | Number Pedigree |————— — ( ———— .0 ———— . —————————— . ? T • •* OA f f y wheat -rye/ Wheat irye DCtOT)\f ! o preselec- |h«xapl...... i—— — d nlantte p i 85 120- ! 55 . 78 79 | Lanca-L5067q 104 120 70 «85-125 14

Aurora-L5067q 11 0 ! 1 20 90 195-120 5

C521?7-W11 86} 150 100 } 105-125 11 i

F2 hexaploid plants are longer than the octoploid parent, but on the shortest among thee influenc th me octoploi th e observedb f o y e ma d . e longeTh r ones correspon n thai d t respece hexaploith o t t d strains used as parents, the cv. Lasko among them.

Semi-dwarf EMl rye material was also directly crossed to hexaploid triticale n thiI . s case, however e progeniesth , , althought shortno d di , seem promising, with a certain similarity to the Bokolo type, based on Tom Thumb wheat [3].

The epistatic effect of the EMl rye dwarfing gene on the wheat genome f octoploio d tritical s alswa e o foun Wandely b d Szigad an t t [4].

Several problems arise in connection with the possible impact of the EMl rye on the breeding of short triticale. The first is connnected with the dange f unfavourablo r e pleiotropic effects simila o thost r e associated

248 wite Rjvtth hß wheat gene n thiI . s case, however e octoploid, th som f o e s and hexaploids derived from the me mor b see eo t mpromisin g thae th n offspring of direct triticale- rye hybrids.

Another proble o considet me possibilit th s i r f obtainino y g short, homogeneous triticale varieties n botI . h cases ,n octoploi i tha s i t d hexaploid and hexaploid-rye hybrids short, fairly uniform strains were obtaine o widn d e an dsegregatio e typs th notewa e n f o occurrind e ry n i g material carryin1 germplasmEM e th g .

As mentioned before, some of the F^ octo-hexa were perfect in plant type, o sucn althoug 2 hF gooe h th d late plantn I . s coul e selecteb d d and much grain shrivelling was observed, but the fertility was quite satisfactory. Wit a longeh r perio f segregatioo d n occurrin n octo-hexi g a crosses improvemen f seeo t e dexpecteb typy ma n efurthei d r generations. This has to be verified in the near future.

REFERENCES

[1] KOBYLYANSKU, V.D., 1975, Effect of the dominant character of short strains on some quantitative characters of winter rye, Hod. Rosl. Aklim. i Nas. 19, 5/6:495-502. [2] ZILLINSKÏ, F.J., BORLAUG, N.E., 1971, Progress in developing tritical n economia s a e c crop, CIMMYT, Mexico Res. Bull 17:27. [3] KISS, A., KISS, J.M., SALLA1, T.G., 1977, Improvement of some favourable traits: tillering type, earliness and seed quality of short hexaploid triticale. Interspecific hybridizatio n plani n t breeding e .Eight th Proc f ho . Congres f Eucarpiao s , Madrid, 169-177. [4] WANDELT, W., SZIGAT, G., 1982, Möglichkeiten zur Nützung der Roggen - kurtzstrohmutante EM1 für die Schaffung von Triticale, Ausgangs materials. Tag. Ber. Akad. Landwirtsch. Wiss, DDR Berlin, 1981, 104-115.

249 WINTER TRITICALE BREEDING IN POLAND

T. WOLSKI Poznanska Hodowla Roslin, Warsaw, Poland

Abstract

Winter triticale is becoming an important cereal crop in Poland, as it's acreage is expected to reach 1 million ha in 1990. It is to occupy a large part of the rye growing area. Three cultivars are registered and 11 more are under official trials. The actual state of breeding in connection with the main goals is presented. Breeding methods leading to further progress are briefly discussed.

The present acreage under triticale is not large in Poland, despite the great interest of farmers in the new crop. It is estimated that around 20,000 ha were grown in 1984/85 and this should double by the Fall of 1985. An official seed supply of close to 5,000t is a good starting point for the planned 1 million ha in 1990.

The chief aim of triticale introduction is partial substitution of winter rye, grown in Poland in a proportion unique in the world (above 3 million ha). A major part of rye grain is used as fodder, although it's t i containprotei d an s n w somlo contene s i growtt h inhibitors. Possibilities of replacing rye with wheat and barley are limited owing to e predominancth f acio e d soils. Frequen y tspring dr lat e r leso ar es s favourable to growing spring than winter cereals.

Three varietie f winteo s r tritical - Laskoe , Grad d Dagran o - ohav e been registered in Poland up to 1985, 4 others are in the third year of official trials and 7 more are being tested in the first or second year. Three varieties - Lasko, Salvo and Bolero - have obtained breeders rights protectio d threan n e n officiai other e ar s l trial n severai s l countries. e nameAlth l d varieties originate froe Poznath m n Plant Breeding Stations, Chory d Laskian n . Another large programm s beini e th g t carriea t ou d Institute of Plant Breeding and Acclimatization, mainly in Malyszyn Experimental Station. Several winte d sprinan r g triticales have been submitted to official trials.

e effortTh f breedero s e concentratear s n improvemeno d f severao t l complex character n combinino d an s g a favourablthe n i m e manner.

e graiTh n yield potentia e regardeb y ma ls quit a d e satisfactoryn I . the official trials, 1982-84, the widest grown cultivar, Grado, had mean yields 3% higher than standard rye and 4% higher than standard wheat variety e opinioTh . f moso n t grower s positivi t senthusiastic no f i e . Furthermore, in 2 years new strains will become varieties. These candidates gave, in the preliminary trials, more superior yields than Grado (Tabl . Furthe1) e r progres e expectedb y ma s .

251 Table 1. Some characters of two new winter triticale varieties as compared to standards in preliminary trials at 10 locations in 1984 and 8 locations in 1985 (2 years means). t------1 ————— 1 Grain Resist, Test [Tallin*] Frost Variety yield in to lodp weight 'number resist % of in 9 p. kK/hl eec. % ipean score surv. stand labor i — - ——— 5 LA28 D 111 6.4 68.9 156 74 Presto 109 5.2 70.5 70 44 Laeko stand. 101 4.6 69.2 126 14 Grado stand. 99 5.5 66.9 73 ?U Mean stand, t/ha 5.71 —————— i.

In official trials Grado has proven superior in lodging resistance, e standarry e tth od Dankowski poin9 a tn o scoree 8 Zlot0. .y b e Dagrs i o 5 showe28 D a superioritdLA stild an l 5 bettey0. ovey b r r9 Grad0. f o o points in preliminary trials. A number of short and semi-dwarf strains were obtained mainly as transgressions, but were unsatisfactory in yield. Some strains carry differen e tdwarfin ry whea d an tg genes s triticalA . e o n replact sando s e yha ry e soils t wouli ,e interestinb d o obtait g n relatively tall varieties wit a gooh d lodging resistance, analogouo t s Danko rye.

Winter hardines n triticali s s veri e y importane th o r Polant fo te du d frequen d heavan t y fros d alsan t o becaus f snow-mouldo e n thiI . s respect the first Polish triticale, Lasko, is unsatisfactory for local conditions. Later released Grad d Dagran o o represen n improvemena t n i t winter hardiness t onlbu ,e ynewe th som rf o eline e gooar sd enougo t h assume safe cultivatio n north-easi n t f theo Poland mo Tw advance. n i d tests, unfortunately have some serious drawbacks, but in some less advanced lines good combination f winteo s r hardiness with other agronomic characters are expected to be found.

Aluminum tolerance is decisive for replacing rye on acid soils. Triticales differ widely in that respect. Lasko expressed good tolerance [1] and Grado is even better [2].

Most triticales are rather late in development and ripening, and breeding for earlier types is desirable. A certain progress in earliness s obtainewa n Prestoi d . Resistanc o pre-harvest e t sproutin n triticali g e utilized as fodder is only important as far as it assures safe and stable seed production. Lasko is relatively good in that respect, similar to mose varietie ry o treceptivt d an s e wheats like Maris Huntsman. Most other triticales are inferior to Lasko. It was also found in the rainy season 1981 that Laski materia s i superio le CIMMYth o t thaf ro T t crossing-block [2], Among recen a superio s t ha varietie 5 r 28 fallin D LA s g number. In the rainy harvest 1985, seed production, mentioned before and based chiefl n Gradoo y s possiblewa , t witbu ,h more losses.

252 The grain filling of many triticales is also unsatisfactory. Test weight, generally used as a measure of this character, is important, chiefl n vie i f yit'o w s correlation with yield [3] t als bu f ,o it'o s impac n millino t g valu d evean ea certain n e feedinvaluth n i f poultryeo g .

Diseas s becomha e e quit a problee developmen th n i m f triticalo t e breedin d growingan g e resistancTh . f moso e t hexaploid o mildet s d an w t declinno rust d di es- wit drasticallw h no som o t e p exceptionu y r fo s rusts. Susceptibilit o t Fusariury d n an Septoria unhappn s i ay recombination of parental species traits and is one of the most difficult problems to be solved. Recently however, eye-spot has become the most serious diseas f triticaleo e . Among Chory d Laskan n i varieties Presto (CHD 775g^) e quitseemb o t se resistan - followet y Largb d o (LAD 183).

Protein content is on the average 2% higher in triticale than in Polis e cultivarsry h n improvemenA . f thio t s characte s desirablei r t bu , it should not be obtained at the cost of agronomic value, as triticale is above all a source of energy. The feeding value is in most varieties satisfactory [4].

Triticale breeders dispose of good sources of most desired characters, which does not mean that optimal combinations of those characters have been obtained. Still, improvement of resistance to sprouting and some diseases seems extremely difficult with the available germplasm.

e maiTh n methods leadin o t improvemeng f o triticalt e characters mentioned above is recombination breeding in the broad sense. This method offers a very wide range of possibilities. Different types of crosses, within hexaploid triticale as well as with direct or indirect introduction of wheat and rye germplasm, may be used. On the other hand, interaction between wheat and rye genomes makes results of crosses more unpredictable than within whea r ryeo t . Transgression n mani s y character e oftear s n noted. They were observe Choryin d Lask and nresistanc in i lodgingto e , winter hardiness, earliness, test weight and falling number. Tn most intergeneric crosses the influence of the wheat and rye parent is below expectationss i wit t hi sproutino S . g resistance (Merker, personal communication) e otheth rn O .hand , dominant dwarfing gene f wheao sd an t rye exert a visible effect on plant height of octo and hexaploid offspring. Undesirable pleiotropi m ThumTo c e effectb th Rlvt f o ßs gene make the utility of this type of dwarfness doubtful although the rye EM1 gene may prove less harmful.

Mutation n t breedintriticalebeei no f muco e ns us e hha onl gTh .y success known to the author (personal communication) is that Nalepa has obtained a promising short Lasko mutant, using a chemical mutagen. This would be the case of improving one character of an otherwise good variety.

CONCLUSIONS

Winter triticale is rapidly growing in importance in Poland. The present state of breeding indicates a real possibility to replace rye by 1 milliow thcron 1990i ne n eo pa h n . A furthe r increas f triticalo e e acreage may be foreseen.

e threTh e registered varietie d elevean s n mor n officiai e l trials represent desired characters in different extents and combinations.

253 Recombination breeding offer a broas d rang f possibilitieo e s owino t g e width e applicatio f o inter-generin c crosses. Still e intergenomth , e interactions in many cases make results unpredictable and are the cause of many observed transgressions. Some recent communications speak in favour e possiblth f o e effectiv f mutatioo e us e n breedin n improvemeni g f o t triticale.

REFERENCES

] AN10L[1 1985, A. , , Breedin f triticalo g r aluminiufo e m tolerance: In , Genetic d Breedinan s f Triticaleo g d EUCARPI3r ,e th Proc Af o . meetine Cereath f o lg Sectio n triticaleo n , 573-582. ] WOLSKL[2 , TYM1EN1ECKAT. , , 1982E. , e presenTh , t stat d prospectan e f o s improvement of winter triticale in Poznan Plant Breeding Stations, Postepy Nauk Rolniczych 5_:3-26. ] TYMIEN1ECKA[3 WOLSK1, E. , , MADKA,T. , 1985M. , , Breedin f winteo g r triticale for improvement of agronomic value, In: Genetics and Breedin f Triticaleo g d EUCARPJ3r ,e Procth A f o meetin.e th f o g Cereal Section on triticale, 445-454. [4] RAKOWSKA, M., BOROS, D., RACZYNSKA BOJANOWSKA, K., 1985, Nutritional value of Lriticale grain as compared to wheat and rye, In: Genetic d Breedinan s f Triticaleo g d EUCARPI3r ,e th ProcA f o . meetine Cereath f o lg Sectio n triticaleo n , 675-683.

254 LIST OF PARTICIPANTS

BAENZIGER, Dr. P.S FARINELLI, Prof. U . Monsanto Director, Alternative Energy Sources Chesterfield, Missouri, USA and Energy Conservation Department present address: C.R.E. Casaccia P 240C , 0 Departmen f Agronomo t y 00100 Rome, Italy Institut f Agriculturo e e Universit f Nebrasko y a FILEV . K.ADr , . Lincoln, Nebraska 68583 0915 Bulgarian Academ f Scienco y e Institute of Genetics BARABASZ . Dr , Sofia 1113, Bulgaria Wheat Breeding Department Cereal Research Institute D M. GALE . Dr , P.O. Box 391, Plant Breeding Institute H-6701 Szeged, Hungary Maris Lane, Trumpington Cambridge CB2 2LQ, UK BIANCHI, ProfA . Director, Istituto Esperimentalr pe e CAO, Dr Mingwei la Cerealicoltura Institute of Nuclear-Agricultural Science Via Cassia, 176 - 00191, Rome, Italy Zhejlang Agricultural University Hangzhou, China BLANCO, Prof. A . Istitut i Miglioramentd o o Genetico GIORGI, Dr. B. Via Amendola 165/A ENEA-FARE, Divisione Tecnologie 70126 Bari, Italy Biologich Agrarie e CRE Casaccia P 240C , 0 BOGGINI, Dr. G. 1-00100 Rome, Italy Istituto Sperimental Cerealicoltura l r pe e a Sez di Catania KAO, Dr. K. Via Varese - 9512 3 A ,3 Catania, Italy Institute of Plant Biotechnology N.R.C f Canado . a BORGHI, Dr. B. Saskatoon, Saskatchewan, Canada Istituto Sperimentale per la Cerealicoltura 3007 . Angel0S. o Lodigiano (MI), Italy KONZAK, Dr. C.F. Washington State University BOZZINI, Prof. A. Dept. of Agronomy and Soils FAO Regional Representative for Europe Pullman, Washington 99164A ,US Via Terme de Caracalla 00153 Rome, Italy LA FIANDRA, Dr D Istitut i Biologid o a Agraria CEOLONI. C . Dr , Universita della Tuscia ENEA/FAR - EDivision e Tecnologie Via Riello, 01100 Viterbo, Italy Biologich e Agrarie e C.R.E. Casaccia, CP 2400 LUNDQVIST, Dr. U 00100 Rome, Italy Svalöf AB, Section of Plant Genetics, S-268 00 Svalbv, Sweden D'AMATO, ProM f Director, Istitut i Geneticd o a NARAHARI, Dr. P. Universit i Pisd a a Biology and Agric Division Via Matteotti, I/A - 56100, Pisa, Italy Bhabha Atomic Research Centre Trombay, Bomba 0 08540 y , India DE PACE, Prof C Istituto di Biologia Agraria OTTAV1ANO, Prof. E . Universita della Tuscia Dipartimento di Biologia Via Riell - 0110o 0 Viterbo, Italy Genetica, Universita Via Calabria, 26 - 20133 Milano, Italy DRISCOLL . C.JDr . . Waite Agricultural Research Inst. PORCEDDU, ProfE . Universit f Adelaido y e Istituto di Biologia Agraria Glen Osmond, Universita della Tuscia South Australia 5064 Via Riello, 01100 Viterbo, Italy

255 ROSS1, Dr. L. ULLRICH . S.EDr , . Director, Division Biological and Washington State University Agricultural Technologies Dept. of Agronomy and Soils C.R.E. Casaccia, CP 2400 Pullman, Washington 99164, USA 00100 Rome, Italy WOLSKI. T . Dr , RUTGER . J.NDr , . Poznanska Hodowla Roslin USDA-ARS Agronomy Dept. Wspolna 30 University of California 00-930 Warsaw Davi A 9561C sA US 6, Poland

SALAMINI. F . Dr , WON, Dr. Jong-Lak Max Planck Institute für Zuchtungsforschung College of Natural Sciences 5000 Köln 30, FRG Gyeongsang National University Jinju, Gyeongnam, Republic of Korea SCARASCIA MUGNOZZA, Prof. G.T. Rector, Université délia Tuscia YAMAGATA. H . Dr , Via C. Decollate Kyoto University 01100 Viterbo, Italy Facult f Agriculturo y e Departmen f Agronomo t y SIGURBJORNSSON. B . Dr . Kitashirakava-oiwakecho, Director, Joint FAO/IAEA Division Sakyo-ku, Kyoto 606, Japan Wagramerstrasse 5, P.O. Box 100 Vienna 1400, Austria

SIMEONE, Dr. R. Istitut i Miglioramentd o o Genetico SCIENTIFIC SECRETARY: Via Amendola 165/A 70126 Bari, Italy MALUSZYNSKI. M . ,Dr STANCA, Dr. M. Scientific Secretary Tstituto Sperimental Cerealicoltura l r pe e a Joint FAO/IAEA Division Sezi Fiorenzuold . a D'Arda Wagramerstrasse 5, P.O. Box 100 29017 Fiorenzuola D'Arda (Hiacenza), Italy Vienna 1400, Austria

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