Development of chickpea near-isogenic lines for Fusarium wilt race 0

Abstract

Pairs of chickpea near-isogenic lines (NILs) with resistance/susceptibility to Fusarium oxysporum f. sp. ciceris (Foc) race 0 have been developed using three different intraspecific recombinant inbred line (RIL) populations: CA2156 × JG62 (susceptible × resistant), ILC3279 x JG62 (susceptible × resistant) and JG62 x ILC72 (resistant × susceptible). NILs were obtained by searching residual heterozygosity in advanced RILs using the sequence tagged microsatellite sequence (STMS) markers TR59 and TS35, closely linked to the first gene of resistance (Foc01/foc01) on linkage group (LG) 5 of the chickpea map (Cobos et al. 2005). The progeny of heterozygous plants was genotyped and homozygous descendents (aa and bb) for both molecular markers were selected from each RIL. In order to contrast genotypic and phenotypic results, the progenies were evaluated for disease reaction to Foc race 0 under controled conditions. The preliminary results confirmed the coincidence between the genotypes obtained with the molecular markers and the phenotype evaluation. Taking advantage of the complete sequence chickpea genome, the genomic region involved in resistance has been localized around the marker TS43. Seven candidate genes have been selected to be genotyped in segregant populations in order to develop diagnostic markers to be used in breeding programs for Foc race 0.