Rapid Mapping of Quantitative Trait Loci for the Growth Habit in Peanuts Using Bulked Segregant Analysis

Abstract

Lateral branch angle (LBA) is an important agronomic trait that represents the plant’s growth habit in peanuts (Arachis hypogaea L.), and obtaining the ideotype is the goal of breeders. Although numerous studies have been conducted in the past few decades on both spreading (prostrate) and erect growth habits, the underlying mechanism governing the LBA remains elusive. In this study, bulked segregant analysis coupled with next-generation sequencing (BSA‐seq) was employed to map major quantitative trait loci (QTL) controlling LBA. Spreading (S) and erect (E) bulks from progenies of a recombinant inbred line (RIL) population (Xuhua 13 × F458) were sequenced. Through Δ(SNP‐index) analysis, we identified eight regions on chromosome B05 among 152,650,001–159,955,000 bp and one region on chromosome B09 corresponding to the genomic interval of 154,908,001 to 154,918,000 bp. The regions on chromosome B05 were further narrowed down using single nucleotide polymorphism (SNP) markers, and the gene associated with peanut LBA was mapped around the marker 15‐156 (156,921,591 bp) containing one annotated gene named Arahy.XAW92V, which may play a role in regulating cell growth. The results presented herein not only demonstrate the efficacy of BSA‐seq as a rapid strategy for mapping quantitative traits, such as LBA, but also provide compelling evidence supporting Arahy.XAW92V as a promising candidate gene associated with LBA in peanuts.