T. E. Chikasha¹, R..M. Chiulele², W. Nkhata³, B. Muatinte⁴, L. Santos⁵

¹Eduardo Mondlane University, Plant Production Department, Mozambique, Maputo, chikashatatenda@gmail.com
²Eduardo Mondlane University, Plant Production Department, Mozambique, Maputo, chiulele.rogerio@gmail.com

³ International Centre for Tropical Agriculture, Chitedze Agricultural Research Station,Malawi, Lilongwe, W.Nkhata@cgiar.org

⁴Eduardo Mondlane University, Biological Sciences Department, Mozambique, Maputo, muatinteb@uem.mz

⁵Eduardo Mondlane University, Plant Production Department, Mozambique, Maputo, luisasantos47@gmail.com

Abstract

Introduction/Contextualization: Acanthoscelides obtectus Say (bruchid) is the primary post-harvest pest of common bean (Phaseolus vulgaris L.). Identifying resistance sources and loci is critical for breeding. The southern Africa common bean panel (landraces, breeding lines, varieties) remains uncharacterized for bruchid resistance genetics.

Objectives: This study aims to: (i) identify bruchid-resistant genotypes, and (ii) discover genomic regions associated with resistance.

Methodology: A panel of 188 common bean lines was evaluated for bruchid resistance using seed perforation counts and damage percentage metrics. Genotyping used 50,000 single nucleotide polymorphisms; genome-wide association analysis was conducted.

Expected Results: Significant genotypic variability for bruchid resistance is anticipated. Resistant accessions across market classes are expected to serve as resistance sources. Genomic regions on chromosomes Pv03 and Pv07 are projected for association with resistance. Validated regions may combine with the APA locus (Pv04) for durable resistance.

Conclusions: This work will pioneer insights into bruchid resistance genetics in southern African common beans, enabling marker-assisted breeding.

Keywords: Common bean, Acanthoscelides obtectus, Genome-wide association study, Resistance breeding.