Bi-directional Quantitative Trait Locus Sequencing (QTL-Seq) identified candidate genes and diagnostic markers for sterility mosaic disease resistance in pigeonpea

Pigeonpea is emerging as a climate-resilient legume with the potential to address the shortage of yield and nutrition for a growing global population. In most of the pigeonpea-growing regions, current elite cultivars are susceptible to sterility mosaic disease (SMD). To mitigate the yield losses caused by this disease, we identified genomic regions associated with SMD resistance on chromosomes Cc04 and Cc11 using the QTL-sequencing (QTL-seq) approach. QTL-seq is a cost-effective and high-throughput approach to identify associated genomic regions for the specific traits, by pooling extreme samples, thereby reducing sequencing. The GBS based QTL mapping was done at F2 generation by Saxena et al., in 2017 and we have performed QTL-sequencing of extreme bulks of this population at F8 generation (RIL population). In this study, we identified the associated genomic regions on chromosomes Cc04 and Cc11. Moreover, we have identified the candidate genes, markers, and observed protein structural changes in a key disease resistance related protein, offering new insights into the genetic basis of SMD resistance in pigeonpea