QTL Mapping of Resistance to Bean Weevil in Common Bean

The common bean weevil (Acanthoscelides obtectus [Say]) is an important postharvest pest of common bean (Phaseolus vulgaris L.) seed. To expand the current knowledge of resistance to A. obtectus, a quantitative trait loci (QTL) analysis was conducted using a common bean population of 210 F4:5 recombinant inbred lines derived from a cross of Solwezi, a susceptible bean landrace from Zambia, with breeding line AO-1012-29-3-3A that possesses resistance to A. obtectus. This population was genotyped with 5398 single nucleotide polymorphism (SNP) markers, and evaluated for resistance to A. obtectus and seed weight. Three QTL for resistance to A. obtectus were identified on chromosomes Pv04 and on Pv06. One of the QTL on Pv04, named as O4.1SA, was previously reported as the arcelin, phytohemagglutinin and a-amylase, (APA) resistance locus. The other two QTL for resistance to A. obtectus are new. In addition, four QTL for seed weight were identified on Pv04 (SW4.1SA), Pv07 (SW7.1SA), Pv08 (SW8.1AN,SA), and Pv09 (SW9.4SA). The AO4.1SA and SW4.1SA QTL for A. obtectus resistance and seed weight, respectively, co-localized on Pv04. Once markers linked to the identified QTL for resistance are validated, they could potentially be used in marker-assisted breeding to accelerate development of common bean cultivars with resistance to A. obtectus.