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Polyploidy and Aneuploidy in Guayale

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Polyploidy and Aneuploidy in Guayale 2 8 2 5 2 8 l I~ 11111 . 2 5 Ii& ,= 11111 . :~ 11111 . 11111 . ! 3 2 1.0 3 2 m 11111 . I~ 11111 . 2.2 W I" I.:.: IIF6 .';. ~~~ I:.:l ~ I!: :;: I~ .0 :i ~~ L:;, " ~ 1.4 1.1 "'L;.~ 1.1 U:L;.u -­- - 11111 1.8 . 14 16 ,111111.25 111111.4 11111 1.6 11111,·25 11111 . 11111 . MICROCOPY RESOLUTION TEST CHART MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU OF STANDARDS·J963-A NATIONAL BUREAU OF STANDARDS·1963-A Polyploidy and Aneuploidy in Guayule 1 By A. DOROTHY BERGNER Formerly associate cytogeneticist, Special Guayule Research Project, Bureau 0/ Plant Industry, Soils, and AgriculltLral Engineering, Ag/'icultura~ Research Administration CONTENTS Page Page Chromosomal range in gllaYllle __ 1 Loss of chromosomes by aber­ Polyploid series in natural stands rants_____________________ _ 22 and commercial strains______ _ 2 Chromosomal varianLs within Euploid populations and the p.ol),ploid series _________ _ 24 Btrains________________ _ 2 Ol'igm __________________ _ 24 Aneuploid stmins_________ _ 3 Hapluids from tetraploids .. _ 25 "Int.ermediate" type______ _ 3 Anellploids from diploids__ _ 25 l\Iaterials and methods________ _ 4 Offtype normals from trip- Chromosome mOl'phology______ _ 5 loids and tetraploids___ _ 26 Chromosome behavior in pollen Aberranls from triploids and ~lOther cells _______________'_ 7 tet,raploirls_____________ _ 28 :.... Diploids_________________ _ 7 Offtype normals from aber­ ~ Tl'iploids________________ _ 8 rants_________________ _ 30 • ~;.: Tetraploids______________ _ 12 Sectorial chimeras________ _ 30 ::i Plants wit,h :;higher chromo- Factors limiting aneuploidy and 15 polyploidy in guayule_______ _ 31 . so~ nU1~rs---------- 18 Summary___________________ _ ~ HapMds--- ------------ 34 ~llen __ ~__________________O _ 20 Literature cited______________ _ 36 ;, 7-J ~ ~ c\1 vi ~ ~ <tROMOSOMAL RANGE IN GUAYULE ~JIn th"l-fall 6f11942 LeRoYJ Powers and W. B. McCallum collected ~eds of gnaytJTe (Parthenium aJ'gentatum A. Gray) and mariola (p. iJ}canum H. B. K.) in Mexico and Powers and Walter T. Federer Ci:>llected seeds of these same species in Texas. Early in 1943 many of "these seeds, together with those of certain of the commercial strains developed previously through selection by McCallum and probably of Mexican origin, were germinated and planted in fields at Salinas, Calif. Chromosome studies, especially the determination of chromo­ some' l1umbers, were begun as soon as possible in order to facilitate genetic and breeding experiments. After a few months of exploratory'studies, it was apparent that a polyploid series exists among natural populations and commercial strains of gnayule. Stebbins and Kodani. (13),2 working indepen­ dently, came to the same conclusion at about the same time. 1 Submitted for publication February 27, 1946. • , Italic numbers in parentheses refer to Literature Cited, p. 36. 61J0587-46-·1 2 TECHNICAL BULLETIN 918, U, S. DEP'1', OF AGRICULTUHE Recognition of this was facilitated by the fact that the whole series. was l'cprpsented in the seeds collected in Mexico, Stebbins und Koelani (13) and Powers and Rollins (10) IOllll(l a similar series ill • mariola, From papers written by Russians prior to 11.)36 (9.,3, 5, 6),. it is now evident that they had diploid and t('truploid strains of muriola. and uIso tetraploid strains of guaynle but that they faiLPtl to recognize a polyploid series in their lluttel'ial. Up to the presl'nt no guayule plullts IU1Ve been found with h'ss than 36 clll'OmOSOnH's, 'I'll(' higlH'st lllllnb('r reported thus fill' is 144 among offspring of 108±-cill'OlllOSOIlW 3 plants (8), Probably ('YPl'y numlwl' betweell 36 and 14-1 eouid be found if el10ugh indiyiduni plauts w('t'e exauuneu, Pr('3umaLly some gl'l1ic combiuatiol1f; are yiable for any particular Chl'OlllOSOllW num\)t'r; howt'Y('r, :t distlllctioll should 1H' made betweell th(' predominant clu'omosome nUmb('I'S of populations (stllnds). of gUfiyule aud thosp of Vtll'inllts which OCClll' ill sueil populnliolls or which wpre a result of crossps mndl' in gl'('('l1!tOlH'H'S and flplJ. plantiJlgs at Salinas. A.t Salinas arC' the makinrrs of It gl'('tlt vari.et.y of eitromo­ some nlllnbl'1's, beCU1ISl' dh-('l's(' )'[1('P8 ~of gUfI}'u}p whith In natnl'(' are separated by gl'ographit'al nnd t'tologienL burri('l's hay(' h('('tl nss(\ll1hll'd thert'. 1-.101'(' aneuploids would he' foullcl l111(\(,l' l1aturnl ('oll(lilions wC're ii, not for the fnet tll!lt fn('ultaliyc npomixis is predominant among the higher chrOlHOSOllll' ml'l11bel's of ill(' seri('s (,~, 10), POLYPI,OlD SERIES 1::\ l\NI.TRAL STA~DS AXD COM\IERCIAL STHAL\S ECVLOlD POPGLATlO:'iS A:'iD STlUl;>\S • .Although Stphbins and I\:oc\n.nt (13) suggt'stc'd tlll' hfLsie numh('r of :r. equnlR U for tll(' polyploid s('ri('s, no plnnts whicb hnyp 2,j~ C'qullis 18 haw bc'en found 01' l'l'poI'ted, EN'nus/' of thC' fOI'J11ntion of biyrdl'nts , in 3G+-C'lll'omOSOI11l' 4 plnnts nnd of tri\-n/C'nts in 5-!± -('\tl'omosome plnnts, ,,: t'qunling 18 will \)p wwcl as till' busi(' IHlm\)(,I' in lhis buUl'lin. Aecol'(lingly, :~n elln 1)(' ('ollsi<il'l'('d til(' diploid ('ondition 1'01' lHltUI'fllL~' O('(,UI'J'illg, pl'ps('nt-(Lny populntiollR of guaYlll(', As l'ppoI,t('(l by Bo('hanls('\-n (2) \ hi" 1S tl'll(' for mltl'io1n. n18o, Thl' only ]0\\'(']' llumht'r found in j)(lI'I/tnlilllll tlnn; fnl' is rUI' p, h!lsiCl'OlJ/t01'1I8 L.. in wili('h 2,1; equals :H for 2 COUP('dOll" thalL, POWl'I'S mndp in Tl'xns, At Salinas llll'l'c flrC' ;'') diploill rollp('liollS (2,1'=:30+) from s('('(ls hmT('stp(i in fl lIlol1l1lninOlls l!l"('!l ~()u(h\\'l'st of ~rnpimi, Durango, l\lpxico, Tht·I'(' Iln' ii triploid ('olll'C'tions (:{,t=ii4±) -- 1 from fin indiYidunl Jll;mt growing \rithin tlt(' population from whieh tIt(' diploid ('olledioll -12ii;) \YUS Ohlililll'd nnd till' ollH'l' -1 from difrPlt'nl pla('.('::; Jl('Il.l' Snn Bllrtolo, Dlll'llllgO. Su('h ('tlmml'l'C'ini stmins ns ),[('Cllllurn's lOll, 111, 210, 2;jii. und 2;iR nlso 111'(' triploid, Till' mnjol'ity of tltc' ('oUc'cliollS nt SnJinll~ hllYP 72± eJu'omOSOJ1ll'S llluL tlH'rdol'(' nrl' tPlrn­ pJoicl (4,1'=7:1± /. TIl<' S('('<\S ('UIIl(' ft'om bOlh nntmnl stnnds illld l\fcC'nllmn's ('ollll11('l'einl sl min", Only 0 of til(' ('o1iP('l iO]lt, ll1ndp hv Pow('I'S !lIld )'1('CnllulH in :.,[('xi('o tll'l'U:trllploicL ThC'y ('nme from nil' 3 ± uCtpr a J1umlwr inclirnip1' a polyploid rla~ll, the indhidual l11pmh('r,; o(whi('h • van' in p;mrt tllllllhpr of chromo:;(HlH'''_ .+ nft('r 30 imJh'nlp,; t Ill' diploid rln:;;;, 111<' indh'idunl 111< mucr!l of "'hid\ m!ly be aueuploid,; with 0111' or more ndditional ('hI'OIlIOS(JIlI('';, POLYPLOIDY AND ANEUPLOIDY IN GUAYULcl 3 following 10ciLtions: Onr fro111 nn indiyiclual plant gl'OWillg ·within the populn.tion from which the ('ollrction 4255 mlS obtllinr(lj nnothel' from secds ('oU('eLeel nCilt' Snn JUiLll, N u('\-O Lron j iL third from Catorce, .­ San Luis Potesi, and tlir l'C'111nilling (j f!'Om ':\InjomiL in northt'nst Zacatccns, Th(' tmilS-Pc('Os arCH, of 'J'(lxns is l'!'j>l'Pselllp(l by 362 collcctiolls, Of th('sc ('xtcnsin~ eollcctions eytologi('nl work hHs becn done 011 only 5.:5 nnd pollpu studit's on 4 mOl'e, J.JI hatl72± chromo­ somes, Elcven of thl' 20 lo('alions in T('xns fl'Om \\-1Ii('11 nu' ::;('('(ls wpre coUr('t<'Cl hny(' 1)('en smnpkd. Thus JaJ' 25 of :\ [('('aUtun's !'OIllIlH'l'eiI11 stl"Hins huv(' bppu found to han' n± ChI'0I110S011lPS. TllI'v !11"(~ Nos. :3SH, 49, 180,402,404, -lOO, 40liF, 'HI, 41:3, 41U, 41R, 41!l: 42ti, 42R, 480, 4an, 440, H 1, .,IAA, 4,'i:1. 4;j(j, 4iifJ, 59:1, and 7:~;j2 fill!t l\. ~\[pxinLU sll'ain (42·178 in POWPI'S' Collp('liol1S1. Thus fur no Jwntnllioid or hexnploid llitlul't11 stunds 01' ('o1l1nwl'cinl stmins lulY" ht'!'Jl found. High('" eltl'omosonl<' lluml)(ll's hny(' I)('('n limi(!'!! to ('!'l'(nin indi\-i(!unls in triplOid nll(! tdt'o,ploid populations 11m! ,,(mins undlo lhpil' o1Tspl'ing. Allor the :\I('xicn11 coll!'('tioHs hnw /)('('11 snmpJpd (,)-tologi(,lllly nnd S0111(' hn,Yo brctt studip(i intt'l1Si\-l'ly. IH'!'n liSP lhl' ,\'It01e polyp]oid SPI'II'S is l'('prpsPl1U'd in tltPl1l. and tl!l'I'PJ'Ot'P tlll'Y ufron! tll,t oppol'tunity to wOl'k out tht' J'rlntion umong liL(' l1wmlH'l's or th(' ::;('tw::; • .A "'EUPLOID STHAlXS 8i1,(,P l'('pl'odudion in :It l;i4:±: -('It. ro nlOSOl1H") nnd 4J' (72±-clu'o1no­ SOJ'lWl popu]ntioll::; is pl'pdolllilllllltl)" fuC'ulttltinly Ilpolllietil' dO), it hus lui ill SOIlll' instmIC('S to till' (lstnhlisluHt'llt (If ",Iult nI'l' lss!'lItinlly cl01H'S 01 tlll(luploid ;;.1: and .1.( ('ombillat iOllS. FOl' illStllll('C', conunei.­ • ciul strain 210 8('('mS to JUlY!' ,is chromosom(s, the nllrnb(ll' thut Stebbins und J\.:odimi (1.3) rt'pol'tpd Jor st!'Hill 111. :-Ill'nins 45n and 735-2 8e0111 to hUn' I'~ I'll1'OmOSOllHs i\1 ndditioJl lo Ill(1 pnit' of minia­ tures which is prt'sl'nt, in muny 4,r populations.
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