Integrated To Control Biotic And Season Food Legumes

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h t i * g r u t i trtcrrtrlgcDr.r,lcrur/sjq.srctrtst uIntegrated management systems to control biotic andabiotic stresses in cool season food legumes-TI 1-IntroductionCool season food legumes are grounnover a w'ide rnngc ofcnvironmcnts and aresubject to an enornlous nunibcr o f b i o t ca n d abiotic strc scs.M ; t n o l ' t h s ecancompletely destroy crops o r greatly r*educc thc cluantlty and quality of' theirproducts. There is great variation In thc occurrence of thcsc strcsscs, bothbetween and within the crop species and across tirllc and space. Strcsscs that areknoivn to sc\.erely reduce yields arc pivcn in Tablc 1 . Such rr lrrrgc number ofS FCSSC'S for each of the crops pose a real challenge to scienttats to developeffective integrated stress management systems. This paper seeks to review theinternational progress in developing such components and systerns and todiscuss the problems and solutions that are apparent at this time.Chickpea (Cicer orietinun L.) is a crop of major importance in South andWest Asia, North Africa, a n d Central America. There are very active researchgroups in several countries of these regions. Also, it has been selected a s a targetF.J. Muahfbnuer and W.J. Kaiser (eds.), Expru dingthe Pruducriun und Use Y A C S666-678.0 1984 KIuwcr A c W c Publthhers. Printed in the Netherlaeds.UJ COO/SeusunF d-CropBiotic stressesA b i o t i c stressesChickpeaPusarium w i l t , d r y r o o t r o t ,Ascochyta b l i q h t , B o t r y t i s graym o l d , s t u n t , O r o b a n c h e , podb o r e r , leaf m i n e r , lesionnematode, r o o t k n o t nematode,r e n i f o r m nematode, c y s t nematode,weedsTemperatureextremes,drought, s a l i n i t yPeaS e e d l i n g and r o o t r o t s , Fusariumw i l t , downy and powdery m i l d e w s ,rust,mosaic, s t r e a k , Orobanche,pod f l y , pea moth, bean f l y ,l e s i o n nematode, r o o t k n o tnematode, c y s t nematode, weedsTemperatureextremes,drought,waterloggingFaba beanFusarium w i l t , r o o t rot,c h o c o l a t e s p o t , Ascochyta b l i g h t ,r u s t , mosaics, Orobanche. aphids,l e a f m i n e r , army worm, s t u b b yr o o t nematode, l e s i o n nematade,d a g g e r nematode, r o o t k n o tnematode, w e e d sTemperatureextremes, droughtLentilFusarium w i l t , A s c o c h y t a b l i g h t ,r u s t , s t e m b l i g h t , Orobanche,weedsTemperaturee x t r e m e s , drouqhtLathyrusDowny m i l d e w , weedsD ptrr,r5irrc.ror Grrrerrrl, lCRlSA T. Pnlrorc.lrcrrc P. 0.lrtc//rltrtr Prork-rlr 502 324. /littin. rrrrclI l If 'illrr-t:fi ltrc r.Roircl. If'trrt r.titk .Slrc*r.hr r/ t S t . . B o i r t r - o t r -Irf l;rrt4r. l - CiL.74 R 1' I 'h'Yield losses in cool season food legumes result f'ron several biotic and abioticstresses. T h e most important of these strcsscs on five cool season food legu necrops are listed. and recent progrcss in rcscnrch to allu\,inte some of thcsc isre\.ie\ved. Although i t i s possiblc to control somc atrcsscs b!. thc usc of suchSinputs as agricultural cllemicals, economic and C I I \ . I - C I I I I I C ICI O I C C I Ili171ittheir use in many farmers' fields. Thc most desirable means of stress alleviationis through integrated managcnicnt systems. including host-plant resistance andimproved agricultural practices. There is a n urgent nccd to accentu;itc progrcssto\\rards cultivars that can .ithststnd\,arious strcsscs and give largc iind stableyields. Recent advances in biotechnolog .ma!' o f k r u s thc means by nfhich to d oso. Teams of scientists must go beyond their narroN- specializations and makethe best use of currently available materials and methods within practicableintegrated stress management systems.667Rtot cand a b o t l cslrcsscs afrcct ngfivc cool w a w n food lceumcsY.L.NENE1 and W. REED2Abstractc o n t r stresseslcrop by both thc Intcrnational Crops Kcscurch Institute for the Semi-AridTropics (ICKISAT) in India and the International Uentcr for AgriculturalResearch in the Dry Areas (ICARDA) in Syria. Pea (Pisum sativun L.). fababean ( Vicicrji hrtL.), and lentil (Lcns c.uliriuris Medik.) are grown extensively inboth developcd and developing countries, and have undergone exrensivcresearch and selection. Consequently. f'arrnurs in many areas now have a choiceo f well- rdnptcdci ltivarsthat have high yicld potential, and extensively teslcdrigronornic. prirctices that cnablc them ti? prt ducr:these crops profitably in rnostvc;irs.I n contrast. L r r r l r r orc . grasspea (l. r /tj-r.rt.sst ti\.lc.\- L.) is a crop, grown;rln osrcnt rclyby subsistcncc t'rirrncrs, that has bccn relilrivcly neglcctcd b!.rcscarchcrs. Thu prcscncc of n c r o t o x ussociatcdinwith this food legume is \ .ellk n o w n . and this ('actor may have discouraged rcscarch on its irnpro\,ement.I-iowcvcr. i t is ;i very iiscl'ul crop in many areas. for i t can producc substantialyields under poor agronomic conditions and appears to have relatively few pestsand diseases. Kecently, cultivars containing low neurotoxin content have beendevelopcd in Bangladesh. Canada, and India (Kaul and Combes. 1986; Lal eluI., 1986;Islam and Matiur Rahman, 1991).

Components of Integrated Stress Management SystemsThe productivity of any crop is dependc it11po11a large nunibcr o f cornponcntsof the systcrn in ivhich i t is grn\ .1i. Mast stscss nlnn;lgcn1c1it ini t i l l ti\.cs interact\\.it11 nlany ofthcsc C O I I I O I I I I;111d S , \\,it11 each otlicr. 11111st, rllilst c\.cr tu;tllybcconsidered and tcsted as integrated inputs u.ithiri the crop s!rstcn .riitt crthan assinlple add-on factors.Tlic primary cvnlponcnt incrop i s tllc pli111t gcnc t!,pc t h ; of't'nrs litili tlcssrcscarch opportunities to CSOP ittlpro\,c111 1lfscicrlfists. 1.l'r.c thci-c ; s cop c rturiitics.not o tl! I'or the plalit brccrjcr-x to il1csciisc ;I crop's hi sicyicldpotential bur also, and perhaps more importantlj,. 1c.t incrc;isc ttic crop's gcneticresistance to the many yield-reducing factors that h a w to bc faced in farniinpsituations. As the climatic. edaphic, and biotic thrcats to cool senson legumesvary greatly across the \\'idt' gcograpliic ratlgc o\.cr u.hic11 thcy arc gso\sln, i t i si rlpvssible to design a gcnotypc that will be idcal for all cn\lironn crrts.Consequently, it niust be accepted that tllc rnrtjor itgrn-ecological zones willrequire differins genotypes of each Icguriio crop.Each gcnotypc uftcn rcquircs its a\s.n. spccii llj'dcsigncd. agri lioniic packageof practices that ivill cni hlci t to bc psofirirbl!. espioitcd \ ithiri i t 5 a d i l p t ; t i L I I T iC i. I! 1 01. C L I I I I \ ;it11)1i.h i , ) \ \ I I I P L \ I C ii11d,O I I C I ' i \ t , l l I TII 'l i IIL I C Cill1Sinteract to infliicncc b i t ;111di c ; I-Jioficsirc 5sc3;I tlci c .ijp1i 1 1 5 .Idci lt!,. ; i n optiriii mj7ii 'hiig .o1' :r'opgcnl.)t! pc allti :igrorlonIIc s!,z1cSln s1)ouIrlbc dc\,clopcd for ci chioc;iricr .but [his 1 5 c.lc;ri.l! i l o PC I.II;I -J\s i l ? l tllc. t cbthat can be acllic\.ccj \ .ill he tilt d c c I t - r ol'\il c irlci!l t ;tciicj lt:if gct c. t!17 3.\i,itllhixxific ;igror or icr - c c o r i iot xc ].or ltllci t t 1111'1'c:1 i1ig;LI.C;I\ o \ CI. 1i.111 11tt c) illbc pruu.n. I'or cxamplc. t l l C I I I so\\ingL I I I I tiale a lcipiani spacillg 1.01. such iti .idtlgadapted cultivar may di1ti.1. across thc r a n g 01' boil !,pcsa n d c l i a t e swithin its zone of adaptation. and differing csop protcction 1ncasurc.s ma), bcrequired to c o n b a tthe !icld-reducing strcsscs .hcrctlltsc a1.c I.OLIIIJto belocr. tion-spccillc.Allernitti\;ely. i t night be morc produurivc I O sclcct ;I ran2c ot'pcr oiypcstcrsuit the level ol'agronomic i r l p thatt s call bc ilff' rdcdb!, 1110 l drrncrsin aspecific zone. A high-!.iclding l l t i \ ' i t lth; t.\ 'ill !,icld i\'cll i .hcn prixiclcd with L I S C I inpi ts I C C:III hc pro\,idcd I'ol' those l'a l.nlc1.5 \ \ , l i Lr ' ; I I ;I I'l.i) .d I I c M c' .I I Ca culti\'ar wit11 less yic1J potential b i itt ith rcsist; ncc nlodc -a e c s i s t u to thecclocally doriiinant srresses rniyht be morc usct'ul to the t'iinncrs ijho cannot utilizesuch inputs.Although immunity. or very strong resista ceto pcsts arid discascs would bedesirable. it is much morc likely that lower Ie\.cls of' rcsislancc or tolerance willbe more easily found. This seems truc in casc of faba bean where only moderatedegrees of resistance to Botr.) lisr-inor uPers.:Fr. and B. j i r h Sardinaearea\tailablc. and therefore cffectivc management would involve use of biologicaland nlinin alchemical means (Harrison. 1988). Many landrace cultivars arcfound to h a t e evolved such protection against locally damaging strcsscs. I t iscsscnti;ll to cnsilrc that thc improved cultivars dcvclopcd to rcplacu suchI i i f c f r :;irei not nlorc susccptiblc than thcy arc. urilcss thc local hrmcrs 1ii11.cthe ability to irsc altt'rnatit'c means ol' pest control. For cxamplc. no ncwchickpca cultivar can succccd it1 peninsular India unlcss it has bcttcr Iei.cls olrcsistancc io t.'l s; sii ii\ t i l t . clr!. root rot. coll; rrot. and l/(*/ic,rrlv,r l)r/ ii.)rri,cc,i.(/( 1 i i i h ) I ; I I the Ioc;11 I ; I c ; I c c ' For. CX IIIIPIC.thc t';\b; bc;111 I L H I8 l i . allcsucllcnr loci11 I; tidr;l cin Syrra and I.cb;inon. c;rn bc crossed \ t h B lrt., ti.\rcsis ;intf3f'L 201. to impro\.c its ; cucptab liry(Mallha, IYX.7).The growth and yiclci vf'a crop genotype will be af'fcctcd by all thc compnnctitsof an agronomic pilckagc. 1.e. primary cultivation, sowing, spacing. wccding.soil fertility cnhanccmcnt. and so11n oisturccontrol. C'hangcs in a n y of thcsccomponents can also have major consccjucnccs on the lcvcls o f strcsscs, l i n k 1their ef'fects on the crop. For cxamplc. Jclaying sowing date and incrcasinsplant population significantly rcduccd taha bcan root rot [j.ir.vrrrrlrr r.\ollirri(Mart.) Sacc. 1'. sp. ./irhtir*] and ir.ilt (I.'. o.\.!.\j orrorrSctilcchtcndahl insidc!lcc(Siilill a1111 Asech. li1Si). 111 I l c l i ; elcl ccl,\ou.ing 01' c h c h p c . rci1 1icitI X S r) . t l ; ! s O \l\ l l l g; I S C O C I J , I , I 1 7 1 1 i l\ t L I # 1 1 \ ) L L I L I L, .I C I ( ' I I Y I [ J , I I I I (11, I.CL!LICCLI 1301 r! 11, gr; ! I I I O I 01' , I l c h pI 11 :\ i c I I ( K i r . ht , / ( I / . . 10s') 1.T-IIc . r o p111i1st110t t- c .011\1dcrtt1111 I , \ O ; I I I OI'OI.I I .i t 3 ! L I \ I ; I O \ I I O I I 1 1 11 i c i g k t oL rI O , C LgI I I II;I\C III;I,IOI, LSI' .CL,I\ L ) I I t l cl i o p i l i t 01'o \io\ n cpc\t,.I I I O I I C . \ !IICII; \ I 1 t l cI ; I I I C 111\ ; I I I J r C i I \ )I! ;Ip rtici I; rl![ t l i j z ill;ito r \ l i -, c l i s tp; tl?og . i\ i ; II;ILCt i i110s c l illcs o111i)t11lc t p %\!\ O ? . I S I Lt! I I 1"I I hilil i1113 01)\o\\ 11L . o - J I I I L I t t 1 1 1I I I \ i t d the I I I C s t ) \ \ 11. \Othc d\.a l;iblcpest pi.)pulations ;ire d lutcd;icross ;ill thc liclds In the arcs. "Thcduration and phcnc lopy( !'thecrop can ;ilso bc ot'grcat irnportirncc in cscapingscvcrc peat 11tt;lcks. f-'1)r c irllplt'.&I sh )rt-Ji r;itit)nC L I I I C ' ; L111ay css;tpc scicrcL ; I I I ; I 'CI ' * . , 111\cctIIIi?chlh I I I I I I I LL I I tllcir O P L I I I 111I OtheI I crop o \ L ' Iilorcthan onc gcrlcr;itlt n.Shi r-t di r;it i)t ,cold-tt)lcri itctiickpc; ,11'Clc' clopcJ.u 111cnablc the crclp to rii; turcin t'cbru iry.bc1i)re /I, trrr,ri,gr t.r ,Ascoch! tit bl ght.IJotr! tis graj rnolcl. and hi111 5torrns o i i u r in ntrrthcrn India. I'irkis1;in. a11dhcp;tl.I t I:;alsr) O V I C th;il) L I !urup,roi;ltio )shavs aignlfiuant cI'1kclh C)IIsonic strc bc\.par-ticularl on the suilbornc plan[ pathogens. I'hus. ssicntiats must Icrok c l lbeyond the agronomy of' singlc crops, both in time and space, if thcy arc ti!develop efficient systems to limit crop losses.Soil sol:lrization. using polycthylcne covers, has been found to be o f immcnscvalue (Katan, 198 1). In field cxpcriments, carried out in Syria from 1985-89. soilsolarization for 40 days increased yiclds of faba bean by 331'1/;,,lentils by 6 1 t . l 41'%1.

towards crop improvement, rather than as an cnd rcsult. It is incrcasinglyevident that the success of a new advancc on a rcscarch farm may not prnduccsimilar benefits when transferred to farn crs'ficlds. Part of thc probicm i s ttlatt l cccolopicnl conditions in rcscurch fiolds ilrc often crc ssl! typical of thcssc i nI; rnicrs'Iiclds.ICRlSAT has addrcsscd thcsc problcnis \ .ith sc\.cl.: linlio\.; ticlna. Mostresearch is carried out in projects that involve multidisciplinr ry,crop-bascdtcntlts. :.\ largc arca of ICRISAT's ccntrnl rcscnrcll l'r rn is kcpt ST-cc f ' r o l irrigation :tnd ;tgt-icultur; lcl cmic i ls.otlicr 1hi111.srnalI a y l c i oI'!'cstii / s. tjol s,411p r r m i s i newg crop gcnot!.pcs 111;1t nr'c I c \ ' l o p ci r ln l l.;clc *tsd111 proic .l *d.high-fertility pots, plcrts. atid liclds arc thcn cxtcrisi\ cl!*tcstcd. both i t ) spccificdiscasc and abiotic stress nurscrics and ill Iarpc plots in h pcaticidc-l'rcccarc:r.to dctcrri incthcir silsccptibilit!' to the stresscs t h ; l t tlic!. n1:1!, cncc3 intcrinfanners' ficlds.Another large arca of' the research farm is dcvutecl to f'rir ilingsystemsrcscarch. Hcrc thc ncu. crop gcnotypcs. conlponcnth. and s!.htc117s ;ire tcstc ii nlargc fields within watersheds. S i m u i t a n c o u s l the rxu rt ttcrialsiirld mctllodsare tested on other research stations. usuc ll! in ct3opcration vithnationalresearch scientists in coordinatccl nctivorks. Finull!. thc advances arc t; kcntofarmers' fields. whcrc thcir progress is niortitorcd h!. botll natic?nal andICKISAT rcsc:irch scientists. Thc \vhr,lc j7roccs.s. l'rom tllc" pl.climin r:*.cspcrimelltation to confirmation ol'bcncfits in Siir-mcr 't'ic'lds takes I I I I I I' e ,a r sand is \.er!. cxpensi\ c,f-lou c\:er. t11o proccss ensures tliat the scicntiats arcencouraged to f'ollow their findings through to l,?r ics t i l i r a t i o t and. do notregard the publication of their data as the end product o f thcis rcscnrclt. M a n yfarmers are now benefiting from ncur crop genotypes. a n d o t l c rinnovationsthat have reached them as a result of this system, and m;iny tnore majorin proven entsare already in the pipeline.A good example of irltcgrated niilnagcrtlcnt ol'pcii simt rnts in Canadir is thcstrategy that includes planting resistant cultivarb. using f'unpicidcs f'or seedtreatment, avoiding phcnoxy hcrbicidcs. but using dinitroanilinc a n d triazincherbicides, reducing soil compaction, practicing fall chisel plou, or fall plow plusspring raised secdbcd preparation, using soil indexing to dctrrminc both Icvelsof field infestation and cultivar susccptibilit .and p1311ti11g S C C I I I I I L I ScropsCbetween pen crops (Tu. 1987).The result of' another intcrcsting study M . Spublishcii b), McE\wrl H I I Yeoman (19239). Field expcrin cntscompared four spring faba bean cultivar:,using two pest control programs based on ( 1 ) "standard" control of Ast-oc.l j !u.fii'NhrrcSpegazzini, Dit lcrtrhicsrlipstrci (Kiihti) Filip. and scedbornc viruses and(2) "enhanced" control of'Sirotlu iitteurus, bean lcafroll virus transmitted by thevector Ac))rrhosiplton pisunr, B. fubaia, and U r o t ? lic.iuc -jab(ie c.sin addition topests and pathogens in the "standard" control. The average increase in yield was1.1 t ha- with the "enhanced" trealment.Most traditional systems of agricultural production have evolved to ensurerelative stability in yields, rather than opting for large yields but with greaterrisk. Chickpea in Syria offers a vcry good example. When this crop is sown atthe beginning of winter, the potcntial yields are much greater than thoseproduccd by thc traditionrtl spring sowings. Howcvcr, thc winter-sown crops arcfrccl lcntl!clcslrnycrf by Ascochytn blight. and thc scvcrc frosts that occur in(omc \.c;lrhC;III ;iIso kill i tic p l i l C'onscr ilcntl ,r.this crop is trarlit ionally srnvnill thc sprilig. 11.1such circ mstanccs.the ohvious approach is to acck gcnotypc*that cornbinctl resistance to both blight and low tempcraturcs through thciCgct;tli\.c ph; sc.C'liic.hpc.; hrccclcrs. p;tthologis s,and ph -\iologi\ts f'roniI('/lRT):l ; r l i lIC"1 15/21"Ii; \.ccoopcrirtccl in icrccnitrg thc a ,ail;thlcgcrt pl;rsnl\ \ l t l l c,on\lilc .ahlc, 1 1 c . c . i \ S i r g1l. 1i (11. 1001 1, I t has hccrl po\slhlc to 1le\cl111 h r c c i nI gI I C that realst Ascocl ytablight and low tcrnpcraturt.5 ( K .B. Slngh.1C't'iKIIA. pcrsonill cornrilunicaticrri) arlcl so bill ,idd litah iii!,to thc higli-)1c1Jpotcntial or thc ii irltcr- o\vnL-rop.Kecctit cf'l'orts ot' K;inl: l .1:1d Solh f l Y 0 0 ) inclci,clopin ciu;tl- c; crnchlckpc; .;u t; hlcI'or both \i-llitcr irtid hprlnz sc; \cr ih.arc notc r orthy.Ilroi ghtis ;I [i1;110r ;ihiot cstress kictor. Irrigation. of'coursc. car) clirninatccl'l'ccts of' drought. but u,hcrc i t 1s unavuidablc, brccding for drought chcapc(c.g. short-duration cultivars) and drought rcsistancc should yicld uscf'ulcultivars. Thc ICRISAT shurt-duration kabuli chickpca cultivar IC'C'V 2.rcsis ant tcl f-'i sariitrn\{,ill ;rt d :olerant to salinity, cscapca both tcrmit aldrought and heat strcs.;.-The utilization ot' ho.st-plant rcsist;ir ccto cornbat both blvtic and i hlcrtlcstresses is c,b .ioiisl),a most attr;ictivc option. cncl considcrable rcscarch actlvityis dircctcd [o\\:irds this compr)ncnt. pi rticularlyin thc international agriculturalrcsc:rrch ccnLcrs. Intcn.si\.c scrcctllng of thc ai'ailable gcrrnplasrn has rci,calcdthat rcsistancc can bc found to combat mas[ of the nlajor yield-reducing stresscsin a crop such as chickpea (Pundir LJr [I!., 19XX; Singh V I i l l . . 1991). Howcvcr, thesitnplc identification (I!' a rcsislant source is only the first, and perhaps thecasicst stcp. Thc cornbinittion c.)l'suchrcsistanccs into a comrncrcially accoptnblccultivar can bc L I cI x r c i Jiific lltcl);1nr1 1 11gthypr ct'ss.Alultiplr Stress Hcsistancc7'0 brccd line3 with multiple strcsh rcsistancr: is not casy. 'There are cxarnplcs olcultivars I\ ith conlbir cdrcsist,incc to thrcc strcsscs; but combining rcsistiincc tomore than threc stresses is vcry ditticult. One interesting example of a cultivrtrof oowpea, howcvcr, is worth mentioning. Thc cultivar Iron has combincdresistance to one nematode, four l'ungal, two bacterial, and three viral diseases(Nenc, 1 Y 88).A good example of difficulty in breeding for multiple stress resistance isprovided by the research at ICRlSAT that is directed towards the selection ofuseful chickpea genotypes that have resistance to H. urmigeru, the major insectpest of this crop in India. Screening the available germplasm soon revealedseveral genotypes with considcrable resistance to this pest, but these selections

674Y. L. Nene and W,Reedwere highly susceptible to Fusarium wilt. However, several sourccs of resistanceto this disease were already available, so the brccdcrs, pathologists, and:ntomologists embarked on an intensive program to corllbinc thcsc resistancesinto chickpeas that also possessed all the other required ch ractcrlstjcs.Recentselections show considerable promise, and it is expected that uscfi lcultivars willbe avaiiable for widespread use within the next few ycars. The ICRISAT kabulizultivar ICCC 32 (ICCV 6). combines high yicld with rcsistancelmodcratcp sjstnnccto Fusariurn \rtil I, sorrlc root rots, f l t l i r v i . itndt p r i .so11s a l iryn and,\.as rcleased in Nepal in 1990.A major achievement In intcrspecilic hybrldizntion In chiclipoa ufas thc roductionof F, seeds betwecn the cross C'. o r i c / i i u i ?andlC. ri*l ir osj)c r.t? . t?tP.H. Davis (ICARDA, 1990; Legumes Program, ICKISAT. 1991 ). Somexccessions of C. rrltir osprr n trrlrare resistant/mc-rdcratcl! rcslstant to cold,4scochyta blight, bruchids, Fusarium wilt. and leaf rllincr (Sinph rr rri., 1991).The segregating hybrid progcrlics will be uscful in chickpea imprnvcn entand7rovide an opportunity to transfcr stress-resistan I gcncs fro111I". / i i o . ? i t . ) i t ) io the cultivated species.Building Integrated Stress Management Sjrstemsllarinbility. it1 spacc and timc. of t11c \,i r.lou I'aclr rs.itlcluding strcsscs. tllatjcterrnine the grouqth nrld jtields of'crops cnsurc thai thcrc' can bc 110 universal lucprint for a systenl that would cnsurc thc r n a i n l u myicld of a n y crop in allields and years. Similarly, the ideal genctypt. srhichposscsscs all thc traitsiernandcd both by consumers and producers, including resistance to all otentialstrcsscs, will rlcver be devclopcci. But i t is cclually certain that t l cgenotypes, and farming systenls that arc cusrcntlj, in cans c be greatlyrnproved.A wide knowledge of the relativc ir portiinccof tho stresses that occur locally)r regionally is essential. I t is appropriate to rcproducc a tiiblc (Tablc 2 ) 1'ron.l a.ecent publication (Van Rhcenen, 1991). Thc information contained i n thc lablc:Icarly identifies tllc areas of rcseusch t l i a should Icad to dc\'clopillg i rcgralcd;tress managemcnt systems.Thc traditional systcms and crop landraccs havc nliill! i rl ccog ri/cd r.tucshat have evolved in response to thc strcsscs tllat ha\jc thrcatcncd 171ar)alld his:rops ovcr Inany centuries. Carc 111usl bc takcrl to enhurc th rtally uharlycs t a d chrough breeding are beneficial, not only in increasing thc farmers' profits andtields, but also the crops' stability and sustainnbility. Wc have attctnpted tondicate relationship betwccn rescarch on comporlcnts and in tcgra ted stressnanagement systems (Figure I).Inlegrated n anagenientsystems lo contra/ slresses675Tclhle 2. Desirable characters for ch ckpcaIn d ffercntzones of the world and their priorities forstrcss managcmcn "Zones (*latitudes)D30-45A0-20B20-25Stable, high yield tGood seed quality . 2-12-12-136'1Desirable charactersC25-30Resistance to stressesDiotlcFusarium wiltRotrytis g r a y mold-Root rotsAscochyta blight53-3354Stunt4445Leaf miner-- ity332Excessive moisture-45*-High temperature2242Low temperature---31--1a . 1 highest priority; 9 lowest priority; required;- not required; ? uncertain.b. In case of epidemics, the crop damage is severe.Source: van Rheenen, 1991."Two rapidly c s p l c l i nscientiticgficlds :rrc likcly 10 play :r major roic in thci nprovcrncrit 01' s t r c s s nli nagcrncnt systctns: sinlulation n1c)Jcls and thcaiJ ,ar ccsin gcnc transfer acruas specific and high boundaries.Modorn cornputcrs can now I anJlclargu sin-rulation modcis oc-jntalningseveral variables. Such simulations will not replace field experimentation butthey [nay providc help in testing interactions. and givc indications of the likelycffccts that may rcducc the nced for complex experimentation in field trials ovcrmany seasons (Rabbinge and Bastiaans. 1989). For example, CHICKBUG. ncomputer-based decision aid for insect pest management in chickpea and otherwinter grain legumes, provides information about ffelirorrrpa and derives rherequired advjce which c;m be used to make a sound management decision(Mcl ityreand Titmarsh, 1989).

676Y.L. Nene and W. Reed/rrtcgruted rrtanagentenr systems ro control stresses677ICA RDA, studies on wide crosses, use of tissue tulturc techniques, applicationsof genetic engineering, and molecular marker techniques for the improvementof chickpea and lentil are in progress (ICARDA, 1990, 1991). In addition,desirable gcncs from unrelated plants cauld be usefully transferred to thcscIcgunics.Even without such new technologies there are many advances available now.and in the pipeline, that can give farmers substantial increases in profitabilityfrom thcsc Icgumcs. I t is essential that research scientists should take thescndvanccs to thc farmcrs' fields, rather than leave them buried in rcscarchjournals and confcrcncc rcports. Scientists should actively seek partnership withextension workers and farmers to finally transfer useful, integrated stressrnanagcmcnt technologies.Assistnncc rcccitfcd t'rnm Ms. V. K . Shciln and M r . V . S . Rcddy in thcprcp;ir;iLli. Il 01' I I I\ I I ! I \ I \ L ' I \ I g r ; c I ' ; I L ' l I I Oy \l d g d .A\.Abiotic Stras Management* Fmtlrra,I nnrll rel .Sdntnwn* AcmraavrFi,prrr I. Suggcstcd rcscarch emphasis ( - - - . high.modcratclj hlyh. JIIJnormal) andrelationship betuccn components and systsnl of intcgr: tcJs t r c bn1i1n;1g nic11[In ci)oI scdson I'oodlegumes.The potential for biotechnology lo enable the rapid transfer of' spccificresistance genes looks particularly exciting. I t is already known that some uscl'ulresistances are present in the wild relatives of chickpea and lentil 111atcould notbe transferred by conventional plant breeding techniques. Research on widehybridization and embryo rescue in chickpea is in progress at 1CRISAT. At.4hrlcl-K;lh1ni. XI 1.' . S , I I LX iI 1. . \ I . C ; ; I I I , K )' . I:I-E ;I);I.S( . j r n c'4. rCi '. C I I .j' ,111 1K;itan. J . 1')X)i. ' / IOr\c.tr\,sII72: 143- IJtC.'ll; i h, l,I .111rl 01tlh1r 1097 111 /i,lrt/ I I * I , I I I ( , . \ I r r [ r r ' r t (/ '( r:I( IoI , t i I . ; I I I I I .I5I\ I L ' I I Oi111i1 11. i,. li thj.f'r( l.c'r.tlrti. .\o/ (111 / I I I I I I 11I It rA.\l op.I I I I I /p p 28x-2nv ICLI\. I. S, it'L ll ,AC'1,41 l'rclcccJ rig h o , i h . ('. ihcrr.,i.r\C'I.\Ki'hauhun. I'. 5 . . SL'IIC.i',L. Jot1.1rlwn. C ' I , . I u , I c . M. I). Silxcna. N . In. Siirdar Singh. Sh rn1.1.S. B. Silhr;iwat. K L.iiurf )rJ,J K.K u i x l 0. P.Kulnar Kao, J . V . 1). K. and Slthanantham,S . 1988 /.:/It-i.t.\ o/ SorI.'i'r/krri:trrrot r1t1 f't, t otrp lrunrl C . l i . k pKescarcht .Hulletln no. I 1, I h pp.I'at.iriclicru. A c l h rI'railcrh.a1nd1.1.IC'KISA'I'.t.l. rr soi .J . (1. 1988. /'lotrr /'cll/t /O,q,'!7: I hX-201.IC'r\Kl)A. ItIi)U, k.i c)J L u g u n cImprt.)\crricnt Program. ,,l urrtulHtptrrr /ta IY;UO, 381 pp, .-\icppt).S) rln: lC.'AKL)A.I I I I I C ' I I I)rogr;11 1.I II ,.I IIIII I/N c ) o /orr I'M). 3.13 pp. AIcppo.IC',.21{[1.4 l l ) L I I . Filogl I,U LIIIIC'S I ' I , 1C'.4K1):2. Htrct,lrrc,/r rtr &rrry/rrc/cnrkIsl:r ll. M. A , and hli tlur K i h n i hln , 190 I . In. , J r l t r r rrrrt PII/. L .\/ I,I(( , ( , / I I01I Q//I,,\ .st,(I I I I ( / , / l tI1'11rh t t \/III/Ji / ,,II /Ji,/rt,,\qpp. 1-7 t J , i : i n 1 ,tlntlhri cri I' .IL L , I.l l l l l t l lC'l{lh:\ 1K;lnlal. XI. arid Solh. hl, hl, 13. 10'10, In. C'lirt,X/ r.irrtr rlrr, ,Vi crrr.rPrr/c.rc,llrrrg.r oj //rca .Sc*iotrtl/ I I , I , IIIl I; , IrIhI, I/ r/,111 , ('i11t/ hi twI t r r i r o r pp.r ( 285-286trt,(cdk, kt. A . van Hhccncn. \! c'S;ISSII.I,ti. J . H';ilh ,rlrcl S. 1). I I . i I I ) . lPat.tnc.hcru. Arldhra I'rddcsh. Indiii: IC'HISA'T.K;irh .1'. U,.' I I N , I I K. K , S l i g 0.l :ind i j h i r i bl, [ 1'. 198Y. I r t rC'lr (hp( i r o t \'L,\! t i \ii,//t,rl21: 21-23,Kdtan. J, I YU I , .41ttiit rlR k s i i t p \ i ,I/ ' l u p1 Y:u 2 I /I -23b. o/o Kiiul. A . K . and C:ombcs, D. (cds.), 1986, Lu//u.ru.r ur1r1Lo h,vri.sm,334 pp. Ncu York: T h r dU'orldh1cdlc.al Ke\carch t:ounJut on.Lal. M. S., Agrawal, I. and Chitale. M. W. 1986. In: l,urli! rus(ind Imrhyristrr, pp. 146-lbo (eds. A .K. Kaul and D.Combes). New York: Third World Mcdical Research Foundadon.

M A N A G E M E N T OF VERTISOLS: ICRISAT EXPERIENCEManagement of Vertisolsfor Maximising Crop ProductionICRISAT ExperienceAbstract\lcr i oI L I ;CL I I i lloortantgruup 01 boils in the semi-arid tropics(SAT) of lndiaa clacill clu. d1 llcy h , \ vhigh watcr-storage capacity and high productionpc tcnt ;il,u l i i l lrclil inrunde .-utilisedbecause of the difficulty of managingtheas a t i l \ , n dlhr use 01' traditional tecl nology.Drought and poor drainageitre I H ' I I pioblcnis %hic.tldiscourage most larincrb from cropping these soils intllc rainy season and n1ab.e them resort to post-rainy cropping.r\ 1et:hnoiogy based on the watershctl concept, broadbed-and-furrow systemr r dland malicgenlent, use 01 lrnproved implements, high-yielding varieties,double-cropping and intercropping syslcnls, balanced use of fertiliser and goodcrop rnariayernent practices har been e\ olved and tested for X years at ICKlSA'rCenter, near Hyderabad. I'he tcchriology offers the possibility of increiisingyield to 3 to 5 tonnes/ ha and ofgiving profits up to 2509b on the investment. Thein pruvzdtecl nologyrcduces boil and water loss and increases production. It islikcly to iniprove the employment porential and well-being o f t h e people of theSAI.The technology needs t r a l sin different agroclimatic environments in lndiaand also crit calevaluation and modilicat onelsewhere.The Vertisols, commonly known as black soils, and associated sails with verticcharacteristics, cover 73 million ha of the geographical area in Jndia; about 28million ha of theseare true Vertisols. About 80% 'of the Vertisols in lndia lie in thestates of Mahtlrashtra, Madhya Pradesh, Gujarat and Andhra Pradesh, 13% inKarmataka and Tamil Nadu, and the rest in other adjoining states (Murthy et al.this symposium). Unique features of this region are that it lies in a seasonally dryclhgatic belt. The rainy season is short (with only 2411, wet months) and rainfedfarming is generally practised. It is no exaggeration to state that the Suture of grkulturcin these six states lies in the efficient management of Vertisols.I)fimni ct 01. (198 1) have divided

op c rturiitics. not o tl! I'or the plalit brccrjcr-x to il1csciisc ;I crop's hi sic yicld potential bur also, and perhaps more importantlj,. 1c.t incrc;isc ttic crop's gcnetic resistance to the many yield-reducing factors that haw to bc faced in farniinp situations. As the climatic. edaphic, and biotic thrcats to cool senson legumes