Heterogenous inbred families-derived Near Isogenic Lines for growth habit in Dolichos bean [Lablab purpureus (L.) Sweet]

Identification of markers linked to loci controlling economically important traits, including growth habits, helps the selection of genotypes with desired growth habits at the seedling stage itself in crops, with no exception of the dolichos bean. Near isogenic lines (NILs) differing for a target locus are the most appropriate genetic resources for the identification of dependable genomic resources for use in a marker-assisted selection of genes controlling growth habit. In the present study, we found that 30 F_2:5 progenies derived from a cross between determinate and indeterminate parents segregated for a few morphological traits, including growth habit. A total of 30 F_2:5 progenies were regarded as heterogeneous inbred families (HIFs). Among these 30 F_2:5 HIF, seven were segregated only for growth habits. From these seven HIFs, seven pairs of plants differing in growth habit were selected and were regarded as candidate NILs for growth habit. Of these, only six pairs were segregated for growth habit as inferred by polymorphism for alleles at SSR marker (LPD 19) linked to growth habit. Of these, only four pairs of NILs showed monomorphism (>80%) at most of the 94 background SSR markers and hence were regarded as the most putative NILs. These NILs serve as ideal genetic resources to assess the effect of growth habit genes on non-target traits in the dolichos bean.