Identification and characterization in common bean of a putative homologue to the Arabidopsis Indehiscent gene.

Pod shattering represents a key component of the domestication syndrome in common bean, because it makes this species dependent upon the farmer for seed dispersal. Attempts to elucidate the genetic control of this process have led to the identification of a major gene(St) linked to the presence of pod suture fibers involved in pod shattering. Although St has been placed on the common bean genetic map, the sequence and the specific functions of this gene remain unknown. The purpose of the current study was to identify a candidate gene for St. Arabidopsis thaliana INDEHISCENT gene (IND) is the primary factory required for silique shattering. A sequence homologous to IND was successfully amplified in Phaseolus vulgaris and mapped on the common bean map using two recombinant inbred population (BAT93 x Jalo EEP558; Midas x G12873). Although PvIND maps near the St locus, the lack of complete co-segregation between PvIND and St and the lack of polymorphisms at the PvIND locus correlating with the dehiscent/indehiscent phenotype suggests that PvIND may be not directly involved in pod shattering and may not be the gene underlying the St locus. Alternatively, a more precise phenotyping method needs to be developed to more accurately map the St locus.