QTL mapping of seed hardness trait in common bean (Phaseolus vulgaris)


Sandhu K, You FM, Conner R, Balasubramanian P, Hou A (2018) QTL mapping of seed hardness trait in common bean (Phaseolus vulgaris). Joint Annual Meeting of Canadian Phytopathological Society and Canadian Society of Agronomy, Winnipeg, MB, June 18-22 (poster).


The seed hardness trait has a profound negative impact on cooking time and canning quality in dry beans. This study aims to identify the genetic factors associated with this trait, and develop associated molecular markers to better understand and tag this trait. A recombinant inbred line (RIL) population was derived from a cross between hard- and soft-seeded black bean parents H68-4 and BK04-001, respectively. Ninety-two RILs and parents were grown at two locations in southern Manitoba during the years 2014-16, and under greenhouse conditions. Seeds from both the field and greenhouse grown RIL populations were tested for seed hardness traits. The hydration coefficient and stone seed count were estimated by soaking the seeds overnight at room temperature. For mapping of genomic regions contributing to the trait, the RIL population was also genotyped using genotype by sequencing (GBS) approach. The QTL mapping revealed that in addition to the major QTL on chromosome 7 at a genomic location previously reported to affect the trait, novel QTLs with significant effects were also detected on chromosome 1 and 2. This study demonstrated that multiple genetic factors are involved in the control of this complex trait.