PATHOGENIC RACES OF Fusarium oxysporum f. sp. ciceris IN CHICKPEAS GROWN IN GUANAJUATO STATE, MÉXICO

Abstract

At El Bajío region of Central México, chickpea (Cicer arietinum L.) yields are limited by root rot such as wilt caused by Fusarium oxysporum f. sp. ciceris (FOC). Knowledge on the prevailing races of this pathogen could guide efforts to use appropriate resistant cultivars. The study identified FOC races present at the El Bajío, Guanajuato State by using specific molecular markers. Isolates from five chickpea producing counties were analyzed (Celaya, Salvatierra, Valle de Santiago, Huanímaro and Pénjamo). Twelve primers were used: seven RAPD-type arbitrary sequences (OP1-01, OPI-09, OPI-18, OPF-06, OPF-10, OPF-12 and OPF-16) associated to races 0, 1A, 1B/C, 2, 3, 4, 5 and 6 of F. oxysporum f. sp. ciceris; and five SCAR-type sequences (FocR0-M15, FocR1B/C-N5, FocR5-L10, FocR6-O2, and FocR6-P18-FocR0-M15) derived from RAPD markers previously identified. Markers showed presence of four FOC races in Guanajuato: 0, 1B/C, 4 and 6. Races 0 and 1B/C that produce the yellowing symptom, and race 6 that induces the wilting symptom, were highly frequent. A pathogenicity test was performed taking one sample from each isolated race, plus a race 5 isolate from Sinaloa State upon the differential genotypes: JG 62, Sanford, P 2245, CRIL 1-53, CRIL 1-94, CRIL 1-17, CRIL 1-36, and WR 315. Infection was promoted by immersion of the root system into liquid inoculum. The results from the inoculation test validated the racial identification made with the specific molecular markers. Since differential cultivars CRIL 1-36, WR 315 and CRIL 1-17 showed to be resistant, they could be used as parental stocks in the breeding of resistant cultivars against FOC in México.