Genome-wide characterization of AhBAG genes in peanut reveals their role in bacterial wilt resistance and hormone response

Background The BAG gene family, encoding Bcl-2-associated anti-apoptotic proteins, plays pivotal roles in regulating plant growth, development, and stress responses. Peanut (Arachis hypogaea L.), a globally significant oilseed and cash crop, is highly valued for its economic importance. However, systematic genome-wide analysis and functional characterization of the BAG gene family in peanut remain largely unexplored. Results In this study, we identified 13 AhBAG genes in the peanut genome, which are unevenly distributed across 11 chromosomes. Phylogenetic analysis revealed that these AhBAGgenes, together with BAG family members from other plant species, are classified into four distinct clades, underscoring their evolutionary conservation. Segmental duplication was identified as a major driver of the expansion of the AhBAG gene family. Notably, AhYSVF0U exhibited significant upregulation under Ralstonia solanacearum infection and abscisic acid treatment, suggesting its potential involvement in mediating peanut resistance to bacterial wilt. Conclusions This study provides comprehensive insights into the evolutionary and functional characteristics of the peanut BAG gene family and offers valuable genetic resources for molecular breeding programs aimed at improving stress tolerance in peanut.