Pudriciones radiculares en leguminosas de grano:

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(1)222-9G. j, COLOM. INFORME DE CONSULTORIA SOBRE PUDRICIONES RADICULARES EN LEGUMINOSAS DE GRANO / Abawi , George S. oct. 3 - nov. 20 - 1987. (coLoIA) pçj?'-i./ VI. 15841.

(2) 357 y /. II. r. /. el. ..JI4!J.'. • ,•. IAN DI NO. o o. N -J z. Jnforrne de Consultoría sobre. ¿7 V PUDRICIONES RADICULARES EN LEGUMINOSAS DE GRANO" Dr. George S.bawi Corneli University Octubre 3 - Noviembre 20, 1987 (Evento Técnico 2.3.7). fI1TI. 1. PROGRAMA COOPERATIVO DE INVESTICACjQN AGRKIOLA PARA LA SUBREGION AN[)INA. P!flhII('A. 1fI1. -.

(3) 4. COLOMBIA: Beans are the rnojor food lec»rne crep corsu'íed in the country and grown on 138000 ha. in 1985. Peas are the second important crop with an average production area of 27000 ha. Fababeans are grown on about 4000 ha. Other crops producod or consumed in Colombia are lentils, cliickpeas cowpeas, and nRing bean. Considerable amount of lenUis, peas, beans, and other legumes are imported annually at the present time. It was not possible to vsit production fields in the Pasto area, but spend the time at the CAl OBONUCO station in Pasto discussing mothodologies for research on soilborne pathogens, root disease problems on food legume crops and management strategies. Research on leguminous crops being conducted at the station deals with determining the causa' agents for the major disease problems, evaluating the performance of solcted gerrnplasm and investiçjating Ihe effectiveness of available control options such as the use of fungicide treatments and others. The group considered Fusarium wilt (F. oxysporum f. sp. pha.seoli ), Rhizoctonia- root rot (R. solaril ), web blight (mustia- Thanatephorus cucumeris ), and white moid (moho blanco- Sclerotiriia scierotiorum ) as the major disease problems on beans. Fusariurn root rot (Fusarium spp.) and stem borers were considered the main problems on fababeans. Fusarium-wit (F. oxysporum f. sp. pisi), Fusariurn- root rot (F. solani f. sp. pisi ), stem borers, viruses, Ascochyta blight, dowriy mildew and powdery rnidew as the important pest problems on peas. In a previous trip to the Pasto- Funes-Ipiales production areas in 1985, the major root disease problem observed on beans was Fusarium wilt, but also 10w incidence of both Sclerotium blight (S. ro(fsii) and Fusarium-root rot. Severa¡ bean unes that hayo performed weU in the Pasto area and expected to ha y o resistance to Frarium-wilt include TIB 3042, Frijolica 0-3.2 (E 605), lOA LLano Grande (E 1056), ORO-V-4, 8, 11, 16, 21, and other Unes that are being tested now at OBONUCO. A low incidence of Fusarium-wilt (F, oxysporum f. sp. pisi was found in a pea fleld near Cajica. Peas in this field were grown In rows on a trellis and were very vigorous and with heavy pod load it was estimated al 5 to 6 tonslha.). Other diseases observed were downy mildew (Peronospera pisi ), Ascochyta blight (Ascochyfa spp.), and stem borers. Severe incidence of Fusarium-Wilt W1S -..iound.in a. 1.5 JiaJield near Susa-Bereda-punta de Cruz. The soil of this fiold was hoavy and poorly drained. In addition, the grower did not practico a crop rotation in this fiold. Other diseases present.

(4) 1 'were Ascochyta bliqt., nd stem boçers. Peas grown in association with potatoes and corh in a nearby fluId en tlie saíne farrn Iooked rather good with no majo:r problerrL 1 he sail of tuis fleld had a better texture and appeared with a bettor drainage. Howovor, it is hkely that the fertUizrs, pesticid's and otlier inputs usad un potatoes have contributed to the vigorous growth and red uced disease incidence :6 .eas grown ini association with potatoes. The symptoms of Fu sariu:'m- wilt were also detected in two poorly growing peas in a .fiéki neCaca j ta rd anothor noar Jonesano. Tho sofls of both fie1d., wre. heavy, r' tcixturu arid pooriy. drairiod. Fnsocts darnagein both 1feI ds unU tIwi u wuro SyrnptorTlL; thaT resumbied P ythlurrcjot rot 1tithe socond fluid. Oniy limitad syrnptoms of FusL p rnrøt. rot we observod ori fababeans ín a fle!d near Soraca ¿nd'nother n oarI j b . nosano. Rust, chocolate spot ano stem borers njury. wre aIsodbservod Qn fababeans ir théso he l Us A lentil fiold ner Uenesan showed considerable chiorois, necrosis but without a diagiostiç yrnptorns of Fusriumw1I. It was thought that this.problem couid .e due tO :iflfOCtiÓnbyPyjhj rn or Phylop/ithora spp. The Iatter diigtiosis neod to be confirmed by alternpting to isolate these fungí on agar media (e.g., on acidified water agar). Another lentil fieid nea,r Tibana appeared to be free of •- oot diseases, but had sorne insects (minadores) damage and a 10w .evel of rust. A very severe incidence of Sclerotium bUght (S. ro/fsii ) was found in a bean field near Garaqua. High percentage of the plants were chlorotjc, wilted and exhibited [he white myceliai growth of the fungus with the diagnostíc small, round, and brown scierotia on stem tissues near the soil Une. A closeby pea field of the same grower had a very severo incidence of Fusarium- wilt. Another pea field on a different farm was found with a severe problerns of both Sclerotium-bijght and Fusarium-wilt. A planting of chickpeas on the sanie farrn had a severe incidonce of S cIerotium-blight unU Fus ar j umwjlt (F. oxysporuíti f. sp. cice,! ). A cliickpea íieId near Huatica had a very severe problem of Ascochyta biight (Ascochyta spp.). Fields of beans peas, ancf a srnali planting of chickpeas were observed en several farnis in the urea of Pasea. A pea fie!d liad a severe incidence of root- knot nematodes (Meloidogyne spp.) and sorne Fusarjum- wilt, ancl insect damage. A bean pianting in the saíne fleld showed symptoms of root- knot nematodo infoctions and Severe incidence of anthracnuso Ascochyta- blight unU leafininores.. j..

(5) -IR)LIJ'I. ¿J1,:;cI1. ii'. i,. u . wiU symptoms and also a low incidonce of Ascochyta bi rind anthracnose. A severo damage of white ÍHes (mosca blanc Wliite fijes darnago ws sorne by Ieafrninors were also present. detected in another bean íiod that also sliowed a severo Ascoçhviblight and Iow level of Fusarium- root rot. Root- knot infections, sorne symptoms of Ashy- stem blight (Macrophomina phaseolina and Ascochyta blight ocurred in another field. This field was very wet and the seeds wore planted oxcessiveiy deep. Ashy- stem biight is severo and ono of the major disease problems on beans grown in the Quilicho de Santander area.. Exceilent germpiasm evaluation and breeding trials of peas and beans were observed at the ICA research station (Centro de InvestigaCion "La Selva") in Rio Negro. These triais : we r e extensivo, well organized and maintained properly. The facilities al the station have been recently updated and appear adequate for the research being conducted. High incidence of Fusarium- wilt (F. oxysporum f. sp. pis¡ , possibly race 2) was present in the arcas of The even and high severity of Fusarium- wilt at the the pea trials station will makes it possible to evaluate pea unes without the need Root- knot nematodes were also for artificial inoculations. fóund on peas, but at a low dcnsity. Sorne plants exhihitod syrnpl.orns rosurnbliriçj tliose incited by Pythiuni spp., but ihis observation neod lo be confirmed by isolalion to be rnade from Infectod tlssues on seleclive agar media. Stem borers injury was Tiie group also indicated that Ihere is severo on poas lii tIioo plots. sbm' Rhlzptoilaroot rot R so/am ) on peas but t WS na Røot disease prob'ernL possibie to, observe durtr Fthls visit beari trials j rIuded tlhizoctonia-root rol, rootbbserved in knot nematodes'.(M&oidogytW spp) and 'infEtlons with sympiofli resunbIing those of Pythiu1oot rot.. íhoctonia root rol known to be of major irnportadde lo beans qrown in iho Popayan aren. Ascochyta- biight was the majdr . foliar diease problern. Darnage by borers in the stem and near tHe' growing pointswas observed as wel! as damage by cutworms. Beatl fields of a arm near the station had a severo Ascochyta- blight in oie field, vyVere cutworrn darnage in a second plan ting, whoas the1tfd, planting liad sorne anthracnose and Ascochyta- t1iht.. 1. .1. d 1 ean is being conductod or Very Interesting rsearch,ç1jDoaS coordinatoc1 by tho group rt the CetroÑicíonat de Investigacion It wasintetflg lo OOf tJat dernonstratino th1 "1 IBAI iAl A 1. 1.

(6) HÍ. -. arge oea seods ( 1 mm n damter) had better ernergerice, tower dsease incrdenc, hhhr yietd add ihus higher proíit return than srnJl seeds ( 55 im ui darn), Ao, yieid of piçfls plantod with pea seeds that were cIScoIored or wih frsIor19 wa J ower lhan piot plwited with cfetj od f the rne si4e rfe iiost IrquntIy isolated fungi fror ínfoçted S w1 e $ psçs cf Aç/yt R/uzocton,a Fusw'u, id AtÓrrfa t was shown that the use of chicken or cow mnL,r lit 5 o O t/ha reduced root diseaso :nfections in the greerihouse Th ffect of thse manures on root disease incidence anç yiek wU\bvaIuated n the freld Growng peas en ridges th":'r&.'1Q tø i iQ: ,:cm high resuRed in reduced incdence of rot Qt and gher l yeId Severi fungicide seed treatments ha y a' be'n'evaj:r.jated t.r 'tes of 1.2 te 2.4 gm/kg seeds wtth captan and bent havng thd hest effect en yied n addition considerable rese a r h . ,has;been çorUctod en the evaluation of unes for res istance te "A'soó '.hyta Wt, a nthracnose,. and powdery rnIdew Several Unes, 'have boen deritifiod vith al good eveI of tuierace to triese dieises and will e used in tho breding program Also, fungicides S LI Ch' . 8SBravQ,,'.Whd Boniato controlled Ascochyta-, bhaht when flrst appHéd ' at 5% di•se incidence and thon repeated every 15 days. Many bean Unes are being eva!uated for resistance. te Fusadum wi!t in the arcas of Narino.. Ancash and ICA Tundarna. are considored tolerant, wherea.s Sangre Toro as resistarit. GENERAL OBSERVATIONS. a. Major root disease puUiogeris observed were Fusarium oxysporum f. sp. phaseofl, Rhizoctonía solani, Meloidogyne spp., Sclerotjurn ro/fsii, M acrophomjna phaseolina and F. solani t. sp. phaseoli on BEANS; F. oxysporurn f. sp. pisi, R. soIani S. roffsii, Me/oído gyne spp, and F. solanl f, sp. pisI ori PEAS; Fusarj spp. and F. oxyspwum f. p, tabue on FA BABEANS; R. solani on LENT!LS, and F. oxysponim 1 ;p. Coclil and S. roffsjj on CH!CKPEAS Possiblu ocurronce of PythiLim spp. was also suspected en several of tliese crops. b. The prevalence and sevority oí root disoases observed in Colombia suggest the need for tiie developrnont of integrated crep production rnanagement prograrns íor roducinq the irnpact of pest problerns en iood legurnes. There is a need te improve SOil condit j ons, formutate •better crep rotations, adjust p!anting depth, f ormulate effective fungicide and insecticide seed treatments, etc. as Wc!l as the use of resistarit cultivars,where avai!ab!e..

(7) -, Developrnont of such prog rams is possibie in Ihe countíy as thr:m nxporinncr)(J i;r'liors, acqi;ilo íaci lit¡ n, and other ongoing rojnct projo(ls llini ÍIHt uhflod sucli as tho cultivos rnulhptes coordiwited nE 1 llAi [ATA. Aithough. there are many root disease problerns on legurninous crops and speciaUy beans and peas, the incidence and severity of these probiems vary considerably Írom one region of the country to another and thus the needeci control proqrams wili have to be specific for each area. For exampie: Fusarium- wilt, Rhizoctoniaroot rot, Scierotium- blight, charcoal rot, and root- knot nematodes are the majar root disease problern on heans grown in the Pasto, Popayan, Quaraqua, Quilichon de Santander, and Pasca areas, respectively. C.. VENEZUELA Beans (callad caraota in venezuela) are the majar legume crop grown ovar 39138 ha in 1984. However, the local production does not satisfy haif of the needod tonage for in- country consumption which average about 5.6 kg/ capital year. Cowpeas (calied frijol in Venezuela) is an imporlani legurne crop which was The local production apparently grown over 15240 ha in 1984. satisfy the consumption demand. Pons is second in importance afler beans as it is consumad consiciorably. 1 lowever, about 95% oí tlio corisumed tonages are importad os only 4125 ha were planted in 1985. pigeon peas are being produced in the country over sorne 5000 Other legtiminous iaand are Oonumed like bns as írsb or dry. 'bps riund Include lentil t'hiokpe.s, and fababeans but they Lj ñot prodiicd n Venezuolal The ntrst at the present timo is to country . ftthe to satisfy '1rqae th próuction o( bus and peas S.. the Icxal. dsmarid. .. .. .. The national l coordinatpi bf resEac11. çi3alir1g with iecJLlii'iirioUS crops is bein,g conducted at ÇNlAP / FONA1A?P in Maracay. It was very interesting te •firid out t[iit CENtAPl hdused together with tho Agronomy Faculty of the Urvrsdad Osn(ra[ de Venezuela. This ssociatiori ha prometed coçieration amciigthe researchers al botli instltutiøns ind also the. Iny lvernent of •qraduate students in the three students projects through their thestS.rrch. .. For"xample, 1 are conducUng actiJtad'degronømia r the Instituto de.GenetiC . theiç thesis rearoh on legume crops One ctudeit is invetoit in lb Mac)'plonina phaseolirm in th tistariceand inherItrn cowpeas, tlié othor is il!udiatin the rrier1laiice te cowpea sevem. '. ::. •. (I ihI;. -. .. . ,. ...... .. •. ••. ..

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