Fine-mapping of a major QTL for protein content in BR8014887 soybean line

Abstract Soybean is one of the main crops in the world and has great added value. Due to its importance, breeders have focused on increasing their production, leaving aside important characteristics such as grain quality. Today, the protein content in soybean seeds is lower than in previous decades, and this process needs to be adjusted to meet the requirements of the food and feed industry. The inheritance of seed traits is complex, and we are still in the infancy of this area. The elucidation of the metabolic pathways involved as well as the discovery of causal genes will be of paramount importance for the field. The main goal of the present work was to identify SNPs associated with protein content in Brazilian soybean genotypes and fine map the region associated with the protein content on chromosome 20 of the BR8014887 line to identify the possible causal gene. We identified a novel SNP (190-ss715637277) associated with protein content on BR8014887 chromosome 20 that has been shown to account for the causal effect within a region of approximately 116kb. Within the region, we have only one target gene that is annotated as a pre-mRNA splicing factor and seems to play multiple roles in the plant. The identified QTL proved to be stable, capable of increasing protein content and is considered rare. Therefore, it can be a great target for breeding programs to use and thus recover part of the protein content lost over the years.