Inheritance and Molecular Mapping of Wilt Resistance Gene(s) in Castor (Ricinus communis L.)

摘要

The inheritance of resistance to castor wilt derived from 'Haritha' and '48-1' conferring resistance to race 1 of the pathogen Fusarium oxysporum F.sp. ricini has been determined. The F_2 individuals and backcross F_1 families of two crosses Haritha and '48-1' (resistant) x 'Kranthi' (susceptible) were screened against Fusarium wilt in combined tests which indicated dominant control by single locus of tightly linked gene(s). Bulked segregant analysis (BSA) was carried out on F_2 and BV_1F_1 individuals with 186 RAPD primers that resulted in the identification of two RAPD markers linked to resistance that distinguished the bulks. Of these, the RAPD markers OPH-124973 and OPJ-154268 were tightly linked to 'Haritha' and '48-1' at a distance of 5.0 cM and 7.0 cM to wilt resistance. These closely linked markers to the wilt resistance gene(s) provide a valuable basis for marker-assisted selection in castor breeding programs.