Identification of QTLs and validation of molecular markers associated with reaction to Fusarium wilt in the common bean cultivar BRS FP403

Abstract

Fusarium wilt, caused by the fungus Fusarium oxysporum f. sp. phaseoli, is one of the most prevalent diseases in the common bean crop (Phaseolus vulgaris). However, there is little information regarding the genetics of reaction to this disease. Thus, the aims of this study were to estimate genetic parameters, identify quantitative trait loci (QTLs) associated with reaction to Fusarium wilt, and validate the markers identified. A total of 165 progenies of the population BRS FP403 × BRS Horizonte were evaluated. Evaluation was made in 2016 and 2017 in field trials in an area infested with the pathogen in Santo Antônio de Goiás, Brazil. Genotyping of single nucleotide polymorphism and SilicoDArT, where DArT is Diversity Arrays Technology, markers using the DArTseq technology was performed in the F2 generation. Analyses of the phenotypic data indicated the presence of variability among the progenies and the possibility of success from selection, with high estimates of heritability (90%) and gain from selection (37%). A genetic map was obtained with 702 markers and spanned 3069 cM. Five QTLs associated with reaction to Fusarium wilt were identified on five chromosomes. There was interaction between the QTLs and years. Through joint analysis, four QTLs were identified on chromosomes Pv01, Pv02, Pv03, and Pv04, explaining 5.8%–40.5% of the variation. The QTL FOP2.3403H explained 40.5% of phenotypic variation and was stable over the 2 years. From this QTL, two hydrolysis probes were developed for genotyping in a panel of lines for validation. Selection efficiency was over 92%, indicating considerable potential for use in marker-assisted selection.