Introgression and Stability of Common Bean Weevil (Acanthoscelides obtectus [Say]) Resistance in Diverse Market Classes From the Andean Gene Pool of Common Bean

The common bean weevil (Acanthoscellides obtectus [Say]) is a major post-harvest pest of common bean (Phaseolus vulgaris L.) in tropical regions. Developing and using weevil-resistant varieties is the most environmentally and cost-effective means of mitigating the losses caused by the common bean weevil. The arcelin–phytohemagglutinin–alpha-amylase (APA) locus, originally from tepary bean (Phaseolus acutifolius A. Gray), provides effective resistance against the common bean weevil. The APA locus is currently deployed in very limited market classes, and knowledge of the stability of its resistance across different market classes of common bean is limited. The objectives of this study were to (i) introgress the APA locus into selected market classes of Andean gene pool of common bean and (ii) determine the stability of APA-based resistance to A. obtectus (AO) in multiple market classes of common bean. A total of 571 F_5:7 breeding lines derived from crossing the weevil-resistant breeding line AO-1012-29-3-3A (AO-3A) possessing the APA locus with seven Andean genotypes belonging to five market classes were evaluated for resistance to AO. Of the 571 breeding lines screened, 16 were resistant, representing a low weevil resistance recovery rate of 2.8%. These lines are across diverse market classes, including those preferred in African countries. Of the 16 newly developed resistant breeding lines, six were more resistant to AO (scores ranging from 1–1.3) than AO-3A (score of 2), and these can be used for further genetic enhancement of common bean resistance to AO.