TRITICALE Proceedings of an International Symposium El Batan, Mexico, 1-3 October 1973
ARCHIV IDRC-024e MACINT 11251 TRITICALE Proceedings of an international symposium El Batan, Mexico, 1-3 October 1973
Editors: Reginald Maclntyre/Marilyn Campbell IDRC-024e
TRITICALE
Proceedings of an international symposium, El Batan, Mexico, 1-3 October 1973*
Editors: REGINALD MAcINTYRE/MARILYN CAMPBELL
This symposium was co-sponsored by the Centro Internacional de Mejoramiento de Maiz y Trigo, the University of Manitoba, and theInternational Development Research Centre.
Oi958
*The views expressed in this publication are those of the individualauthor(s) and do not necessarily represent the views of the International DevelopmentResearch Centre.
ISBN 0-088936-028-6 UDC: 633.1 © 1974 International Development Research Centre Head Office: 60 Queen Street, Box 8500, Ottawa, CanadaK1G 3H9 Microfiche Edition $1 Contents
Foreword W. David Hopper 5-7 List of Participants 8-11 Historical review of the development of triticale Arne Müntzing 13-30 Development of triticales in Western Europe E. Sanchez-Monge 31-39 Triticale-breeding experiments in Eastern Europe A. Kiss 41-50 Research work with 4x-Triticale in Germany (Berlin) K.-D.Krolow 51-60 Triticale research program in the United Kingdom R. S. Gregory 61-67 Progress in the development of triticale in Canada E. N. Larter 69-74 Triticale: its potential as a cereal crop in the United States of America R. I. Metzger 75-80 The triticale improvement program at CIMMYT F. J. Zillinsky 8 1-85 Prospects of triticale as a commercial crop in India J. P. Srivastava 87-92 Triticale breeding experiments in India N. S. Sisodia 93-101 Triticale research program in Iran M. A. Vahabian 103-105 Triticale research program in Ethiopia F. Pinto 107-115 Triticale research program in Algeria Herb Floyd 117-1 19 Triticale program and potential in Kenya B. A Nganyi Wabwoto 121-124 Triticale breeding experiments in Chile Patricio C. Parodi 125-128 Expanding the CIMMYT outreach programs R. G. Anderson 129-135 Meiotic, gametophytic, and early endosperm development in triticale Michael D. Bennett 137-148 Metabolic factors influencing kernel development in triticale R. D. Hill, A. I. Klassen, and W. Dedio 149-154 Improving seed formation in triticales F. 3. Zilhinsky 155-157
Univalency in triticale P. 3. Kaltsikes 159-1 67 Cytogenetics of hexaploid triticale Arnuif Merker 169-172 Use of chromosome analysis to detect favourable combin- ations from octoploid x hexaploid crosses M.H.deSosa 173-180 Preliminary report on the cytogenetics of tetraploid X diploid wheat crosses R. I. Metzger and B. A. Silbaugh 18 1-185 Triticale diseases review Santiago Fuentes Fuentes 187-192 Triticale diseases in CIMMYT trial locations M. J. Richardson and J. M. Wailer 193-199 Agronomy and physiology of triticales R. A. Fischer 201-209 Early steps on triticale breeding at CIMMYT Marco A. Quiiiones 211-212 Introduction of new forms and types from wheat and triticale Ing. Ricardo Rodriguez 21 3-215 Extending adaptability and sources of new genetic variability in triticale M. M. Kohli 217-226 Production of triticale germ plasm J. Perry Gustafson 227-233 Broadening of the triticale germ plasm base by primary hexaploid triticale production Armando Campos Vela 235-236 Nutritional value of triticales as high-protein feed for poultry James McGinnis 23 7-240 Comparison of the vole, rat, and mouse as assay animals in the evaluation of protein quality B. E. McDonald and E. N. Larter 241-246 Future role of triticales in agriculture L. H. Shebeski 247-250 Historical Review of the Developmentof Triticale
ARNE MUNTZING
Institute of Genetics, Lund, Sweden
Historical review of the development oftriticale, p. 13-30. MUN'rzING, ARNE.1974. Mexico, 1-3 In Triticale: proceedings of aninternational symposium, El Batan, October 1973. mt. Develop. Res. Centre Monogr.IDRC-024e. named Wilson was the first to obtain and AbstractIn 1875, a Scottish plant breeder between wheat and rye. In 1884 theRural describe a sterile F1 triticale hybrid, a cross breeder) about New Yorker contained several articlesby Carman (an American plant Most of his crosses were unsuccessfuland produced only crosses between wheat and rye. reported maternal plants, but also one true F1 hybrid.The first fertile triticale was not until 1888 by a German worker, Rimpau. between 1918 and 1934 at theAgricultural Major work on triticale was carried on of Experimental Station at Saratov in southeastRussia. In 1918 a mass appearance male- natural F1 hybrids between wheat and ryeoccurred at Saratov, all of which were and 1928) sterile and incapable of self-pollination.Hybrid derivatives were later (1927 observed that were more or less intermediatebetween wheat and rye but were true- breeding and rather fertile. hybrids Meister, in 1928, gave a botanical descriptionof so-called balanced wheatrye and designated the new species combination asTriticum secalotricum Sara toviense Meister. Cytological analysis was carried out in 1930and 1931 by Levitsky and Benetz who made a careful study of mitosis and meiosisand stated that the somatic chromosome number in all three families was 56 andtherefore the constant intermediatefertile ryewheat hybrids were definitely amphidiploidsof bread wheat and rye. the In 1934, Lebedoff obtained a wheatryeamphidiploid and was the first to report occurrence of aneuploidy in suchmaterial. The hypothesis that the wheatrye amphidiploidmust result from an apogamouS development of unreduced ovules in the primaryhybrids, followed by immediate data of chromosome doubling, was abandonedin 1936 because of new empirical Miintzing. He succeeded in 1935 in getting a seedsample of Rimpau's fertile wheatrye hybrid. Several seedlings had 56 or ±56chromosomes and consequentlyRimpau's hybrid was obviously an octoploid strain oftriticale and the oldest one known.The Rimpau strain had retained a perfect constancyduring 45 years of cultivation before the true nature of the new amphidiploidspecies became known. The name "triticale" was used for the firsttime in a paper by Lindschau andOehler and had been proposed to them byTschermak. The archaic period of work with triticale cameto an end after 1937 whenexperi- triticale mental doubling by means of coichicine hadbeen discovered and new strains of could be produced in unlimited quantities. The results of more recent triticaleresearch work are also discussed. 13 14 IDRC-024e
RésuméC'est un phytosélectjonneur écossais, dunom de Wilson, qui obtint et dcrit pour Ia premiere lois en 1875 un triticale sterileF1 hybride, resultant du croisement ble >< seigle. En 1884, le Rural New Yorker publia une série d'articies deCarman, Un phytosélectjonneur américain,sur ces mémes croisements. La plupart deceux qu'il avait tentés étajent restés infructueux, ne reproduisant qUe Ia mere, mais l'un d'entreeux avait donné un veritable hybride F1.Ce n'est qu'en 1888 qu'un chercheur allemand, Rimpau, a signalé le premier triticalefertile. La Station Expérimentale Agricolede Saratov, en Russie du Sud-Est,a effectué des travaux essentiels sur letriticale entre 1918 et1934. Des 1918, tine production importante d'hybrides naturels F1entre blé et seigle était intervenue a Saratov,tous males stériles et incapables des'auto-féconder. En 1927 et 1928on constata Ia presence de dérivés hybrides plus ou moms intermédiaires entre le blé et le seigle maisse reproduisant en race pure et plutôt fertiles. En 1928, Meister donnaitune description botanique de ce qu'iI appelait les hybrides équilibres blé x seigle, et ii baptisaitcette nouvelle combinaison d'espèces Triticum secalotrjcum saralovjense Meister. Levitsky et Benetz effectuèrenten 1930 et 1931 des analyses cytologiques et une étude soigneuse de Ia mitoseet de la méiose, a l'issu de quoi ils établirentque le nombre de chromosomes somatiques des troisfamilies était de 56, et quepar consequent les hybrides seigle >
IN 1875 a Mr Wilson reportedto the Botani- picture (Fig. 1) originally published in the cal Society in Edinburgh that ina series ofRural New Yorker and later reprinted in the attemptedcrossesbetween wheatastheJournal of Heredity by Leighty (1916). Be- female parent and rye as the male, he had sides the morphological appearance, thevery succeeded in obtaining true hybrids ofthe low fertility was evidence of true hybridity. kind we are now familiar with. This was also borne out by the characteristic In 1884 the American plant breederCar-rye pubescence on the peduncle, which was man published several communications in thepresent in hybrid plants derived from wheat periodical Rural New Yorker aboutcrosses as the female parent. between wheat and rye. Most of hiscrosses Triticales first came on the scene thanks to were unsuccessful and gave only maternalthe work of a research team at the Agricul- plants, but in one instance thecross resultedtural Experiment Station of Saratov in the in a true F1 plant. This is evidentfrom asoutheastern part of Russia. Approximately MÜNTzING: TRITICALE DEVELOPMENT REVIEW 15
of winter varieties of wheat (Meister 1921). In one wheat plot about 20% of the plants were hybrids and altogether many thousands of natural wheatrye hybrids were observed. They were derived from early flowering wheat varieties that flower rather openly in the dry continental climate of Saratov. Moreover, the wheat plots had been separated from each other by protecting rows of rye, supposed to prevent cross pollination between the wheat varieties. The hybrids were allmale-sterile and incapable of self-pollination. Hence, the thousands of seeds collected from the vast number of F1 plants were generally products of spontaneous back-crosses to wheat or rye. Hybrid derivatives were later observed that were more or less intermediate between wheat and rye, but inspiteof that, were true- breeding and rather fertile (Fig. 2). Such so-called balanced wheatrye hybrids were suspectedtobe polyploid asindicatedin papers from 1927 and 1928; and in 1930 Tumyakov published a report about fertility and morphology of these "wheatrye hybrids of balanced type." Meister (1928) gave a botanical description of thismaterial(see Levitsky1932)anddesignatedthenew species combination as Triticu,n secalotricuin sararoviense Meister. He also emphasized the importance of the new products for plant- breeding work and even published prelimi- nary results concerning baking properties in this material, which he believed nobody had seen before. The cytological analysis of thismaterial was carried out by Levitsky and Benetzkaja (1930, 1931) who made a careful study of mitosis andmeiosis. They statedthat the FIG. 1. Wheatrye. This is the first illustrationsomatic chromosome number was 56 (Fig. 3) published of a wheatrye hybrid, and represents in three different families. Thus, the constant Carman's own work. It appeared as Fig. 339 in the Rural New Yorker on 30 August 1884. intermediate fertile ryewheat hybrids were definitely amphidiploids of bread wheat and rye. during the period 1918 to 1934 the director Investigations of the mode of meiosis in the of theinstitute,G. K.Meister, and hispollen mother cells, as well as on the female associates were active in the field of wheat side,revealedafrequentoccurrenceof rye hybridization. irregularities caused by the presence of uni- In 1918 an extraordinary phenomenon wasvalent chromosomes(Fig.4a). This was witnessed in their experimental fields - aobserved in all three of the families studied mass appearance of natural F1 hybrids be-and was therefore regarded to be character- tween wheat and rye in a number of plotsistic of ryewheat amphidiploids in general. 16 JDRC-024e
chromosome sets, or an antagonism between the female cytoplasm and the male chromo- some set, which represented another genus. Levitsky and Benetzkaja also discussed the mode of origin of the amphidiploids and had to base their arguments on the fact that all the primary wheatrye hybrids at Saratov were completelymale-sterile.Under such circumstances they had to assume an apoga- mous development of F1ovuleswitha somatic number of chromosomes, and that this chromosome set was then doubled in the first division of the egg cell. This view was reluctantly accepted by other workers writing about the amphidiploid wheatrye hybrids during1930-36.Lebedeff (1934), whileworkingatastationin Ukraina, obtained a wheatrye amphidiploid that was essentially similar to those at Sara- toy. He was first to report the occurrence of aneuploidy in such material. A few plants had less than56chromosomes. Lebedeff, when discussing the reduced fertility of the wheat rye amphidiploids, pointed out that poor fer- tility and other disturbances are characteristic of inbred lines of rye. He therefore suggested thatsuchunfavourablepropertiesinthe amphidiploids might be avoided by the use of fertile and vigourous inbred lines of rye in the primary cross. He also emphasized the importance of choosing the right varieties of wheat for the primary crosses. He did not believe that cytoplasmic differences between wheat and rye could be important, because backcrossing of primary wheatrye hybrids to rye had led to quite regular and fertile rye plantsinspiteof their wheat cytoplasm. Lebedeff also demonstrated the formation of unreduced ovules with 28 chromosomes in primary hybrids. After pollination with rye, a plant with35chromosomes had been ob- tained. He suggested that the occurrence of such ovules should also be utilized for the FIG.2.Later hybrid between wheat and rye, production of new amphidiploid strains after fertile and true-breeding. pollination of primary hybrids with the pollen of already existing amphidiploids. He also outlined other ways for the future breeding This disturbed pairing could not depend onof the new material, for which he suggested lack of homology, and must therefore bethe name "Tritisecale." assumed to have had other causes, either a Lebedeff did not publish anything more on general incompatibility between the parentalhis octoploid triticale material. His work may MLJNTZING: TRITICALE DEVELOPMENT REVIEW 17
FIG. 3. Triticum vulgare X Secale cereale. Constant intermediate rye-wheathybrid. Somatic plate of an individual from F1. Chromosome number 56. Enlargementx2700. have been stopped by the approach of theof the same plant were male-sterile as usual. Lyssenko regime and the same influence mayThe entire F1 material available (65 plants) havealsocounteractedandstoppedthe was scrutinized, and in a second plant asingle pioneering work carried out by the Meisterflower with dehiscing anthers was discovered. group in Saratov. It belonged to the same cross-combination as The hypothesis that the wheat-rye amphi-the first, partially male-fertile F1 plant, but in diploids must resultfrom an apogamous all the other 14 cross-combinations no flowers development of unreduced ovules in the prim- with dehiscing anthers could be detected. ary hybrids, followed by immediate chromo- Pollen samples from the dehiscing anthers some doubling, was abandoned in1936when (Fig. 4b) showed that the percentage of new empirical data were published (Müntzingapparently normalpollengrainsinthese 1936).In1931 Icame to the Swedish Seed anthers ranged from about 20to 60%. Association as head of a new laboratory for Measurements revealed that the pollen grains chromosome research and induction of poly- were quite large and therefore probably unre- ploidy in cultivated plants. In my program,duced. This was verified by using this pollen work with wheat-rye amphidiploids was also for controlled self-pollination. From a head included. In the summer of1935, 1had athus treated a single kernel was obtained. It quantity of F1 plants representing15different germinated and gave rise to a plant with 56 cross combinations. In one of these combina- chromosomes, which was the starting point of tions, representing Swedish varieties of wheata new strain of octoploid triticale. and rye, I observed in one of the F1 plants Inthis case the production of a new that single anthers had dehisced and that these triticale strain was made possible either by anthers contained pollen of good quality. Inthe spontaneous formation of small somatic this plant part of the anthers in three differentsectors with a doubled chromosome number, heads were fertile, whereas the other headsincluding anthers as well as ovules, or perhaps 18 IDRC-024e L?k"!'" 4,e.4p 4
4a
FIG. 4a. Meiosis in pollen mother cells showing presence of univalentchromosomes.
even by quite local areas of chromosome one of the heads produced 15 kernels. In this doubling leading to single dehiscing anthers, head there must have been a doubled sector or parts of anthers, with unreduced pollen.since 12 of the kernels gave rise to fertile Such an occurrence may, of course, easily be plantsofuniformappearance(Rinipau overlooked but probably represents a mecha- 1891).The new constant strain (Fig. 5-7) nism of general importance that had been atwas at first grown by Rimpau but was shortly work alsointhe previous cases of spon-afterwards includedinthecomprehensive taneous origin of octoploid types of triticale. material cultivated in a plant-breeding garden Thus,theratherunlikelyhypothesisof in Halle. Guided by serological results that apogamous development, followed by chro-had been obtained with this strain by Moritz mosome doubling, became superfluous. (1933),and that indicated the presence of Though the octoploid triticale types dis-wheat as well as rye proteins,1 succeeded, coveredatSaratov were thefirsttobe in1935,in getting a seed sample of Rimpau's scientifically explored, another strain of thefertile wheatrye hybrid. Severalseedlings same kind had arisen in Germany in1888. had56or±56chromosomes and, conse- The breeder Rimpau, just like Carman in thequently, Rimpau's hybrid was obviously an United States, made crosses between wheat octoploid strain of triticale and the oldest one and rye, and in one of the hybrids obtained,known. This was also verified by Lindschau MUNTZ1NG: TRITICALE DEVELOPMENT REVIEW 19
4b Flo. 4b.Pollen samples from dehiscing anthers. and Oehler (1935). Of particular interest incussions between Tschermak and his German this case is the fact that the Rimpau straincolleagues at the Muncheberg Institute for had retained a perfect constancy during the PlantBreedingResearch.Intheirpaper 45 years of cultivation before the true nature Lindschau and Oehler also point out that it ofthisnew amphiploidspeciesbecamewould be convenient to distinguish between known. differentstrains of triticale by adding the As far as I know, the name triticale was author'sname.Thus,"triticaleRimpau," used for the first time in 1935 in the paper"triticale Meister," etc. by Lindschau and Oehler. This name had During a 5-year period in the 1930's I had been proposed to them by Tschermak, onethe opportunity of devoting much of my time of the three rediscoverers of Mendel's laws.to work with triticale. The results gathered Tschermak carried out much hybridizationwere reported in a paper published in 1939, work with cereals and, for instance, succeededSince this paper is characteristic of the status in producing an amphidiploid between tetra- and problems of research in triticale at that ploid wheat and Aegilops ovala that hetime, 1 shall mention some of the results named Aegilotricurn (Tschermak and Bleier obtained. 1926). There is reason to believe that the My material consisted of six strains of name triticale was coined during verbal dis-triticale (Fig. 5-7, 8-10), of which only one 20 IDRC-024e
FIG. 5-7.Ears of three of the six constant triticale strains studied.Fig.5,Triticale A; Fig. 6, Triticale B; Fig.7,Triticale C. Fig. 5 and 6 represent the types produced by Rimpau; Fig.7is of Russian origin. The cross combination most extensively studied isthat between strains A and C (Fig. 5 and7). represented a union of Swedish wheat andhad been obtained, recombination breeding rye and the other strains had been produced was started, at first by intercrossing triticale inother countries (Germany, Russia, andMeister and triticale Rimpau. To my surprise, the United States). The six strainswere allcrosses between different triticales succeeded partially sterile, but the degree of sterilitywith difficulty, the average seed set being as was different in different strains. The triticaleslow as 5%. There were also reciprocal dif- also differed significantly in vigour, in the ferences in this respect. degree of meiotic irregularity, and in physio- Inter-strainhybrids were foundtobe logical and chemical respects such as winter vigourous. In one of the crosses that was hardiness, earliness, and baking capacity. Astudied in detail, the F1 plants were taller bakingtestwithtriticaleMeister gavea than the average height of the parents, but surprisingly good result,the bread volumewere more sterile than the parents and showed being larger than in the best bread wheata higher degree of nonpairing of the homo- varieties available for comparison. logous chromosomes at meiosis. In F there As soon as more than one triticale strainwas a significant decrease in vigour and, on MUNTZING: TRITICALE DEVELOPMENT REVIEW 21
10
a FIG. 8-10. Ears of three of the six constant triticale strains studied. Fig.8, Triticale D; Fig. 9, Triticale E; Fig. 10, Triticale F. Fig. 8 is of Russian origin, Fig. 9 isthe strain of Taylor and Quisenberry,andFig.10representsTriticaleSvalof(a combination of"SolveteIII"and "Midsomarrâg"). an average, the plants were still more sterile 56 chromosomes that were heterozygous for than the F1 plants. However, in later genera-the wheat as well as the rye chromosomes. tions fertile recombinants could be obtainedA very marked segregation was obtained in that greatly surpassed the parents in yieldthe offspring, but this segregation was com- (Mhntzing 1948). plicated by chromosomal irregularities. New triticale strains were not only pro- Unreduced gametesinhybrids between duced by crosses between constant strainswheat and rye had been utilized earlier - already existing, they were also derived from by myself in hybrids between Triticum tur- crosses between triticale and bread wheat andgiduin and rye that, in the absence of triticale selection of new triticale types with recom-strains at that time (1933), were pollinated bined wheat chromosomes in the offspring.with hexaploid bread wheat. The result was New triticale strains could also be obtained triple hybrids with 42 chromosomes, carrying by pollination of primary wheatrye hybridsthe complete haploid genomes of rye and the with triticalepollen(Fig. 11-13). Inthis two wheat species (Muntzing 1935). As is way, some of the unreduced ovules in theevident fromFig.14,themorphological primary hybrids could be picked up by maleappearance of the triple hybrids represented gametes having the same chromosome num- a harmonious union of the three components. ber, 28. This method led to new plants with Similar work was later carried out by 22 IDRC-024e
FIG. 11-13. Ears of a new triticale product (Fig. 12) in comparison with ears of wheat (Fig. 11) and rye (Fig. 13). Fig. 11 represents "Solvete III," Fig. 13, "Stalrag," and Fig. 12 two different triti- cale plants from the Igeneration of a new triticale heterozygote. This heterozygote arose from pollination of a hybrid between Swedish wheat and rye with triticale pollen. The large ear and kernel dimensions are conspicuous. Fig.11-13 are directly comparable to Fig. 5-10.
Nakajima (1942, 1951, 1952, 1953, 1958, Recent Work 1961,1965)inJapan, and describedin numerous publications. To triticale breeders it is of more interest to know that a similar The archaic period of work with triticales procedure is nowadays successfully used bycame to an end after 1937 when experimental the Russian breeder Shulyndin in Charkov.chromosome doubling by means of coichicine By pollination of primary hybrids between had beendiscovered and new strainsof bread wheat and rye with hexaploid triticale, triticalecouldbe producedinunlimited Shulyndin(1972)has obtainedespecially quantities. However, in many countries, and good triticale types. These products he re-especially in Europe, World War II seriously gards as representing a complete synthesis ofhampered research activities, In the Soviet the three species involved, with the exceptionUnion, moreover, the Lyssenko regime was that the D-genome of bread wheat has beena serious obstacle. Nevertheless, some work eliminated. with octoploid triticale wasstillcontinued MUNTZING: TRITICALE DEVELOPMENT REVIEW 23
Fin. 14.Spikelets of the triple hybrid (a) and the parent species,Triticum turgiduni (b), Secale cereale (c), and Triticum vulgare (d). X20. and later expanded when conditions becameand rye. However, breeding work with octo- more favourable. ploid triticale led to considerably improved I would like to briefly summarize a few strains that in some field trials, especially on of the results obtained with octoploid triticalelight or sandy soils, gave yields equal to those during the last few years. Itis, of course, of bread wheat. Kernel size in these triticale easiest for me to base this information on lines was superior to that of wheat, and this experience gathered from my own material fact compensated considerably for the lower (MUntzing 1948, 1956, 1957, 1958, 1963, seed set of the triticales. Seed quality was also 1966,1970), but special reference shouldimproved to the point of being comparable also be made to the comprehensive work by to wheat. Nevertheless, even the best octo- Ingold et al. (1968). ploid strains could not compete successfully The first primary strains were only theoreti- with hexaploid wheat. cal curiosities with a yield much below the In part, this was due to lack of sufficient level reached by high-bred varieties of wheat straw stiffness in most of the octoploids, which 24 IDRC-024e caused lodging at higher amounts of nitrogen contents, but many other, moresophisticated fertilization. Under such circumstances spray-biochemical variables are involved. A serious weakness in the octoploid triticale types, so ing with the chemical CCC increased the in the straw stiffness of the triticales considerably. far tested, is the enzymatic processes It also helped counteract the reduction inkernel and the tendency to pregermination,if yield caused by lodging. No doubt, however, the ripening crop is exposed to humidcondi- judging from experience made in other coun-tion before harvest. However, triticalestrains and rye tries, a more effective escape from lodging react differently to such conditions, was to breed new materialofoctoploid varieties that are resistant to pregerminatiOn triticale with sufficient straw stiffness. Even if are now available and maybe used for the this goal could in part be attained, there stillproduction of new triticales. cereal remained the main difficulty: an unsatisfac- A general conclusion in this field of tory number of kernels per spikelet, a reduced chemistry isalso that scales and standards fertility,the causes of which are not yet that are well suited for wheat varieties cannot automatically be used for the evaluation of entirely clarified. One main factor, however, is the occur-triticales. Test values, which in bread wheat entirely rence of more or less high rates ofaneuploidy would indicate that the material is for in the octoploid strains. The correlations be- unfit for baking, have little significance tween sterility, meiotic disturbances,and rate triticale. In a recent case quite good triticale of aneuploidy have been studied byseveral bread was prepared from flour having very workers and were recently discussed in apoor values of alpha amylase,according to paper by Weimarck (1973).She concludes wheat standards. that in bulk populations, as well as in pro- Basic cytogenetic work in octoploid triticale By genies of euploid plants, recombined strainshas also led to various important results. (1966, are characterized by lower degreesof aneu- improved technical methods, Pieritz ploidy than primary strains. The recombined 1970) succeeded in distinguishing morpho- strains also have higher fertility and a more logically between wheat and rye chromosomes stable meiosis than the primary strains. Aand confirmed other indirect evidencethat in close relationship was found betweensomatic octoploid triticales (in contrast to hexaploids) chromosome number and fertility,the eu-the univalents occurring at meiosis are pre- ploids having clearly higher fertility than thedominantly rye chromosomes. The rye chro- to be- aneuploids. It should be observed, however, mosomes, therefore, have a tendency that no direct correlation has been foundcome eliminated in contrast tothe wheat between the degree of meiotic disturbances chromosomes that are rarely unpaired. Pieritz in a plant and its fertility. also showed that there is a strict selection Judging from theresultsobtained,the against aneuploidy among the male gametes, present level of aneuploidy in the best octo-whereas all kinds of deviating chromosome ploid strains (in my material about 30%) canconstitutions are transmitted by the ovules. certainly be pushed down stillfurther by Another cytogenetic phenomenon, observed recombination and selection, and this must by various workers, is that in octoploid triti- lead to increased productivity. cale there are not only meiotic but sometimes The economical importance of octoploid also mitotic disturbances, that lead to chromo- triticale is also strongly influenced by kernelsome deviations in somatic cells (Mflntzing quality - not only the degree of shrivelling1957). For this reason, the total number of of the seeds but also the biochemical proper- chromosomes in the pollen mother cells may ties and their relationshipto bread-bakingalso, in some instances, be higher or lower capacity. Therefore, in the breeding workthan it should be. This phenomenon, which during the last decades it became increasingly also occurs in hexaploidtriticale(Orlova urgent to pay attention toanalytical data 1970), is not unique for triticale but has also gathered by the cereal chemists. It is now not been observed and analyzed in various species only a question of test weight and rawproteinhybrids (Plotnikowa 1932; Bleier 1934; Lange MUNTZING: TRITICALE DEVELOPMENT REVIEW 25
1971) and in inbred lines of rye (Rees 1955).carried out at the University of Manitoba Another finding of interest is that spon-during the last two decades. This work has taneous reversions to haploidy may sometimes represented a successful combination of basic occur in triticale (Muntzing Ct al. 1963). Ascytogenetic work withintensivebreeding a rule, however, this phenomenon isquite efforts and was carried out by such men as rare or entirely absent, but in some strains,Jenkins, Shebeski, Evans, Welsh, and Larter reversions to haploidy have been observed (Larter 1968; Jenkins 1969; Tsuchiya 1969; more frequently. Larter etal.1970; Sisodia and McGinnis Itis possible that the interest in triticale 1970a, b; Tsuchiya and Larter 1971). as a potential new crop would have tapered The research program carried out by this off entirely if the efforts had been limited to group and their associates was initiated in octoploid material. However, this has been 1954. The first material used was the hexa- successfully prevented by the enormous de-ploid durum x rye amphidiploid produced by velopment of hexaploid triticales and by the O'Mara. Several additional hexaploid triticales crosses between octoploids and hexaploids. were developed from new crosses, and seeds Although this explosion is much more recent of other existing wheat x rye amphidiploids, than the octoploid story,it may now beboth hexaploid and octoploid, were collected. worthwhile to look back and point out some Many of the best triticalelines from all of the main features in this phase of the life sources were intercrossed. In the Canadian of triticale. program more improvements through selec- Hybridization between tetraploid wheat and tion were accomplished in hexaploid triticales rye was started about 60 years ago. The firstthan in the octoploids. hybrid was probably Triticum dicoccoides x Important progress was made through the Secale cereale, which was produced by Je-discovery of light-insensitive, early maturing senkoin1913. Thefirsthybrid betweentypes, and dwarf and semi-dwarf wheat lines, Triticum durum and rye was described inwhich were used as a source of shorter and 1924 by Schegalow (Plotnikowa 1932). The stronger straw in the triticales. These charac- first amphidiploid between tetraploid wheat teristics(light-insensitivity,earliness,short and rye was reported in 1938 by Derzhavin. straw, and disease resistance, particularly to In this case it was a union of Triticum durum stem rust) represented marked improvements with Secale montanum. Of more interest fromover earlier hexaploid triticales. Parallel with the breeding point of view was O'Mara's the breeding work, quality evaluations of the (1948) amphidiploid between T. durum andgrains were carriedout,andit was also cultivated rye and Nakajima's (1950) com- established that grain of the hexaploid triti- bination of Triticum turgidum and rye. A cales is suitable for use in cattle, sheep, and more concentratedeffortof producinga poultry rations. Since these triticales, which broader and more variable material of hexa- lack the D-genome, were not suitable for ploid triticale was made by Sanchez-Monge bread flour, they could instead fill the need and Tijo (1954) and Sanchez-Monge (1956, for a feed crop in certain areas. 1958)in Spain. This work was primarily In 1969, one strain, Rosner, was licensed made to get triticales of good grain qualityand became recognized as a new crop of as a substitute for a mixture of wheat andcommerce in Canada. Results from livestock- rye that is rather widely cultivated in certain feeding experiments,distilling and brewing regions of Spain. Sanchez-Monge and histests, and also from experimental manufac- co-workers found that it was obviously im-ture of breakfast cereals indicated that triti- possible to obtain, directly, a 42-chromosome cale had considerable potential as a cereal triticale with good properties but believed that crop. it would be possible to improve this material A new and very important phase in the by recombination and selection. history of triticale was inaugurated less than That their optimism was justified has been 10 years ago when it was realized that hybrid- amply demonstrated by the excellent work ization between octoploid and hexaploid triti- 26 IDRC-024e cale may lead to quite valuable products ofCIMMYT and IDRC in Mexico, we became recombination. This was clearly realized byvividly aware of the enormous amount of Pissarev about 1960 (see Pissarev 1966, p.successful work on triticale that has been 286-289); and in 1965, Kiss, in Hungary,carried out herein Mexico by CIMMYT, demonstrated that secondary hexaploids de- particularly by Borlaug and Zillinsky. rived from such crosses were superior to The work started on a small scale in 1963 primary hexaploids (see Kiss 1966a, b). In and was more firmly established in 1964 as a the same year similar evidence was obtaineddirect outgrowth of a cooperative breeding in Winnipeg, Manitoba (Jenkins 1969). program between the University of Manitoba Two secondary hexaploid Hungarian triti- and CIMMYT. At that time a winter-breeding cale varieties were officially registered a few nursery involving most of the Canadian ma- years ago and have been more prolific interial was sown during November in Ciano. Hungarian state trials than any rye varietyFollowing harvest, most of the material was (Kiss1971).Incomparativetrialswith returned to Canada for summer plantings, wheat, their value was equal to that of thebut part remained in Mexico to be sown at wheat variety Bezostaya1.Both the new Toluca during May. From that time there has triticale varieties are cultivated for fodder ofbeen a continuous free, two-way flow and grains or green matter and have given goodexchange of triticale breeding materials be- resultsinfeedingtrialswithmice,rats, tween the Canadian and Mexican programs. poultry, and pigs. Baking trials have shownMany other centres in the world have also that hexaploid triticale flour may be success-become involved in this international work. fully mixed to 50% with wheat flour. EvenIn recent years this work has been carried without admixture of wheat such triticale out on a very large scale, and twice as fast as flour alone is reported to give excellent and in countries limited to only one generation tasteful brown bread. In 1969, about 40,000 per year. acres in Hungary were under cultivation with In this historical survey I have discussed hexaploid varieties of triticale. only one special aspect of the Mexican work The production of improved secondarythat has already been of very great import- hexaploids is now a standard technique used ance and that will certainly have a strong byallbreedersoftriticale,and Krolowinfluence on the future of triticale breeding: (1969a, b) has worked out the cytologicalthe origin of the Armadillo types and the details occurring during this process. I hesi- block of favourable characters carried by tated to use this technique because so muchthem. In a recent paper by Zillinsky and genome-analyticalworkseemedtohave Borlaug (1971) these characters were speci- proved definitely that the A and B genomes fiedas follows:(1) a very high level of of tetraploid and hexaploid wheats were quite fertility, never before encountered in any homologous or even identical. However, cleartriticalebreeding program;(2)improved evidence that this is not the case was obtained grain plumpness and test weight; (3) high from the Universityof Manitoba. By an grain yield per hectare; (4) insensitivity to elegant technique, Kerber (1964) succeeded daylength; (5)earliness; (6) one gene for in extracting the AABB part of bread wheatdwarfness (semi-dwarf F1); and (7) high and found that these extracts were dwarfnutritional quality. plants that differed in many ways from tetra- Since it is highly probable that the Arma- ploid wheat species,and were especially dillos have arisen following a spontaneous adapted to cooperate with the D-genome ofcross to bread wheat, it seems likely that a Aegilops squarrosa. Later, Kaltsikes etal. whole block of linked genes has been incor- (1969) carried out similar extractions. poratedinto one of the chromosomes of hexaploid triticale or that a substitution of Conclusion one or more chromosomes has occurred. IknowthatGustafsonandZillinsky At the workshop on triticale arranged by (1973) have obtained evidence pointing in MUNTZING: TRITICALE DEVELOPMENT REVIEW 27 this direction and with the aid of quite new Thus, we may now begin to wonder to staining methods that make itpossible towhat extent wheat varieties will absorb rye distinguish each rye chromosome in triticale, chromosomes and triticale varieties will ab- and probably soon also most orall of thesorb wheat chromosomes. There are probably wheat chromosomes, full clarity about thecertain limits to this kind of disorder, and constitution of the Armadillo types can be until the ideal reshuffling of chromosomes and expected (Merker 1973). chromosome segments has been reached it Thus, the rye genome in the Armadillos will probably still be useful to retain the old- may have been weakened but favourably concept triticale. modified by the intrusion of one or more Work with triticale is a wonderful experi- gene-blocks from wheat. If this process will ence and a splendid adventure. It is obvious go on still further, the name triticale for such that by continued interaction between inten- material will become more and more dubious.sive breeding work, basic cytogenetics, and However, the species rye has already taken several other sciences, we can really look a revenge by invading one of the wheat forward to a future when this crop will be- genomes. In a series of five papers published come increasingly important for the welfare during the period 1969-72(Zeller1969; of mankind. Sastrosumarjo and Zeller 1970; Zeller and Fischbeck1971;Zeller1972;Zeller and References Sastrosumarjo 1972), Zeller and his cowork- ers have demonstrated that rye chromosome BLEIER, H.1934.Bastardkaryologie. Bibliogr. No. V, which is known to carry several genes Genet. XI: 393-485. for disease resistance, is present in the com- CARMAN, E.S. 1884. Rural New Yorker. mercial wheat variety "Zorba," where it has August 30, 1884. replaced wheat chromosome No. 1B. The DERZHAvIN, A. 1938. Results of work on breed- same thing has also happened in another ing perennial varieties of wheat and rye. Izv. Akad. Nauk USSR, Ser. Biol. N 3: 663-665 German wheat variety,"SalzmündeBart- (In Russian). weizen." In a third wheat variety, "Weique," GUSTAFSON, J. P., AND F. J. ZILLINSKY. 1973. the situation is similar but more complicated. Identification of D-genome chromosomes from In one subline called "Weique Substitution" hexaploid wheat in a 42-chromosome triticale. thereisagain the same substitution as in Proc. 4th mt. Wheat. Genet. Symp. (Mo. "Zorba" and "SalzmUnde Bartweizen." In the Agric. Exp. Sta., Columbia). (In press) other subline of Weique there is a transloca- INGOLD, M., E. OEHLER, AND G. A. NOGLER. tion between wheat chromosome I B and rye 1968.Untersuchungen über Entstehung, Fer- chromosome V. tilität, Morphologie und agronomische Wer- The very detailed analyses carried out by teigenschaftenneueroktoploiderTriticale- Zeller and his associates have also led to the Stämme. Z. Pfianzenzucht. 60: 41-88. detection of a number of other translocations. JENKINS, B. C. 1969.History of the develop- ment of some presently promising hexaploid Thus, for instance, Zorba is homozygous for Triticales. Wheat Inform. Serv., No. 28: 18-20. a specific translocation and the variety Hold- JE5ENK0, F. 1913. Uber Getreidespeziesbastarde. fastforanothertranslocation,involving Z.Jndukt. Abstamm.-Vererbungsl. 10: 311- chromosomes other than those in Zorba. 326. As is well known, much basic work with KALTSIKES, P. J., L. E. EVANS, AND E. N. LARTER. substitution and addition lines has already 1969. Morphological and meiotic character- been carried out by many workers, especially istics of the extracted AABB tetraploid com- Jenkins and Riley. However, as far as I know ponent of three varieties of common wheat. the recent cases in Germany are the first to Can. J. Genet. Cytol. 11: 65-71. KERBI3R, F. R.1964.Wheat: reconstitution of demonstrate that such substitutions may arise the tetraploid component (AABB) of hexa- spontaneously and are present in varieties that ploids. Science 143: 253-255. are economically prominent due to the pres-Kiss, A. 1966a.Neue Richtung in der Triti- ence of such substitutions. cale- Züchtung. Z. Pfianzenzücht. 55: 309-329. 28 IDRC-024e
1966b.Kreuzungsversuche mitTriticale. MERKER, A. 1973. A Giemsa technique for a Züchter 36: 249-255. rapid identification of chromosomes of Triti- 1971. Origin of the preliminary released cale. Hereditas 75: 2. (In press) Hungarian hexaploid Triticale varieties, Nos. MORITZ, 0.1933.Serologische Untersuchung- 57 and 64. Wheat Inform. Serv., No. 32: en an Getreidebastarden. Ber. Deut. Bot. Ges. 20-22. Bd. LJ,l, Generalversamml.-Heft. KROLOW, K. D.1969a.Cytologische Unter- MUNTZING, A. 1935.Triple hybrids between suchungen an Kreuzungen zwischen 8x und 6x rye and two wheat species.Hereditas 20: Triticale I. Untersuchungen an den Eltern, an 137-160. der F1 und der F2.Z. Pfianzenzücht. 62: 1936. Uber die Entstehungsweise 56 chro- 241-27 1. mosomiger Weizen-Roggen-Bastarde. Z iichter, 1969b. CytologischeUntersuchungen an 8. Jahrg., 7/8 Heft. p. 188-191. Kreuzungen zwischen 8x und 6x Triticale II. 1939.Studies on the properties and ways Untersuchungen an F2- (Meiosis), F3- und of productionof rye-wheatamphidiploids. F4-Pfianzen. Z. Pfianzenzücht. 62: 311-342. Hereditas 25: 387-430. LANGE, W. 1971.Crosses between Hordeum 1948.Experiences from work with induced vulgare L. and H. bulbosum L. II. Elimination polyploidy in cereals. Svalöf 1886-1946. In A. of chromosomes in hybrid tissues. Euphytica Akerman etal.[ed.]History and present 20: 181-194. problems, Lund. p. 324-337. LARTER, E. N.1968.Triticale. Agr. Inst. Can. 1956.Chromosomes in relation to species Rev. March-April. differentiation and plant breeding. Conf. on LARTER, E. N., L. H. SHEBESKI, R. C. MCGINNIS, Chromosomes, Wageningen. p. 1-37. L. E. EVANS, AND P.J.KALTSIKES. 1970. 1957.Cytogeneticstudies inryewheat Rosner, a hexaploid Triticale cultivar. Can. J. (Triticale). Proc. Tnt. Genet. Symp. (Tokyo) Plant Sci. 50: 122-124. 1956. p. 51-56. LEBEDEFF, V. N. 1934.Neue Fälle der For- 1958.Polyploidiezuchtung. Handb. Pflan- mierungvonAmphidiploideninWeizen- zenzücht., I. Band, 2. AufI. p. 700-731. Roggen-Bastarden. Z. Ziicht. Reihe A. Pflan- 1963.Some recent results from breeding zenzucht.: 509-525. work with ryewheat. In B. Akerberg and A. LEIGHTY, C. E.1916.Carman's wheat-rye hy- Hagberg [ed.] Recent plant breeding research, brids. J. Hered. 7: 420-427. Svalöf 1946-1961. LEVITSKY, G.1932.Zur Geschichte der frucht- 1966.Cytogenetic and breeding studies in baren, intermediären, konstanten Weizen- Rog- Triticale. Proc. 2nd Tnt. Wheat Genet. Symp. gen-Roggen-bastarden. Züchter, 4.Jahrg., 3. (Lund), Hereditas (Suppi.) 2: 291-300. Heft. p. 76-78. 1970.Die Bedeuting der induzierten Man- LEVITSKY, G. A., AND G. K. BENETZKAJA. 1930. nigfaltigkeit für die KulturpfianzenforschUflg. Cytological investigation of constant interme- Die Kulturpfianze, Beih. 6: 53-72. diaterye-wheathybrids.Proc.All-Union 1972. Experiences from work with octo- Congr. Genet. Sel., Leningrad 1929, p. 345- ploid and hexaploid ryewheat (Triticale). Biol. 352 (In Russian with English summary). Zentralbl. 91: 69-80. 1931.Cytology of the wheat-rye amphidi- MUNTZING, A., N. J. Haism, AND C. TARK0wsKI. ploids. Bull. Appl. Bot. Genet. Plant Breed. 1963. Reversion to haploidy in strains of (Leningr.) 27(1): 241-264 (In Russian with hexaploid and octoploid Triticale. Hereditas English summary). 49: 78-90. Unter- LINDSCHAU, M., AND E. OEHLER. 1935. NAICAJIMA, G. 1942.Cytogenetical studies of suchungen am konstant intermediären addi- triple hybrids from F1 Triticum turgidum X tivenRimpau'schenWeizen-Roggenbastard. Secale cereale and Triticum vulgare.I. Num- ZUchter, 7. Jahrg., 9. Heft. p. 228-233. ber of somatic chromosomes and external MEISTER, G. K.1921.Natural hybridization of characters. Proc. Imp. Acad. Tokyo, 18(2): wheat and rye in Russia. I. Hered. 12: 467- 100-106. 470. Genetical and cytological studies in 1928. Das Problem der Speziesbastardierung 1950. im Lichte der experimentellen Methode. Z. breeding of amphidiploid types between Triti- Indukt. Abstamm.-Vererbungsl. Suppi. Band 2. cum and Secale.I. The external characters Verh. 5.Tnt. Kongr. Vererb. Wissensch. p. and chromosomes of the fertile F1 T. turgidum 1094-1117. (n=l4) X S. cereale (n=7) and its F2 pro- MUNTZING: TRITICALE DEVELOPMENT REVIEW 29
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WILsoN, A. S. 1876. On wheat and rye hybrids. ZELLER, F. J., AND G. FISCIIBECIC. 1971. Cyto- Trans.a.Proc.Bot.Soc. Edinburgh12: logische Untersuchungen zurIdentifizierung 286-288. des FremdchromosomsinderWeizensorte ZELLER, F. J.1969. Versuch einer Identifizier- Zorba (W 565). Z. :pflanzenzücht66: 260- ung der somatischen Chromosomen des Wei- 265. henstefaner Winterweizenzuchtstammes W 565 ZELLER, F.J., AND S. SASTROSUMARJO.1972. anhand seines Karyogramms. Z. Pflanzenziicht. Zur Cytologie der Weizensorte Weique (T. 61: 275-287. aestivum L.). Z. PflanzenzUcht. 68: 312-321. 1972.Cytologischer Nachweis einer Chro- ZILLINSKY, F. J., AND N. E. BORLAUG.1971. mosomensubstitutionin dem Weizenstamm Progress in developing Triticale as an eco- Salazmiinde 14/44 (T. aestivum L.). Z. Pfian- nomic crop. Res. Bull., CIMMYT, Mexico, 17: zenzUcht. 67: 90-94. 1-27.