Mapping of Stemphylium Blight Resistance and Genes for Agro-Morphological Traits in Lens Culinaris.

Mapping genes for disease resistance and agro-morphological traits has great importance to breeding programs and understanding genomics. Stemphylium blight caused by Stemphylium botryosum is one of the major diseases of lentil in Southeast Asia and North America. In order to identify and map the genes for resistance, we developed a population of recombinant inbred lines (RILs) from a cross between two contrasting parents ILL 6002 (resistance), and ILL 5888 (susceptible). These parents also contrasted for the other agro-morphological traits. The RIL population was developed by advancing the progeny of the cross from the F2 to the F7 by single seed decent. The resulting 206 F7 derived RILs were planted in disease sick plots in Bangladesh for two cropping years following a RCB design with three replications. The results indicated significant variation among the RILs for disease symptoms and frequency distributions of disease scores indicated complex inheritance. The agro-morphological traits such as days to flowering, plant height, plant type, cotyledon color¸ seed diameter and 100 seed weight also showed significant variations and the frequency distributions indicated the presence of qualitative and quantitative inheritance. The RILs were genotyped using different types of molecular markers (SSR, RFLP, RAPD and SRAP) and a linkage map of fourteen linkage groups has been developed. QTLs and markers closely linked to the traits have been identified.