Development of dominant sequence characterized amplified region (SCAR) marker linked with plume moth (Exelastis atomosa Walsingham 1886) resistance in pigeon-pea

Abstract

The mode of gene action governing resistance to plume moth (Exelastis atomosa Walsingham 1886) derived from pigeonpea (Cajanus scarabaeoides (L.) Thouars) accession ICPW-94 has been determined and the resistance alleles have been designated as PPM1. The progenies of F2 population and F3 families derived from an interspecific cross C. cajan (L.) Huth ('ICP-26') × C. scarabaeoides (accession ICPW-94) revealed monogenic gene action for resistance to plume moth, and the dominant control by single locus or cluster of tightly linked alleles. Bulked segregant analysis (BSA) of 116 F2 progenies by using 143 parental polymorphic RAPD primers could identify a fragment OPA09910 associated with plume moth resistance in coupling phase of linkage. Further single plant analysis of the 116 F2 mapping population revealed OPA09910 was linked to PPM1 locus conferring host resistance to plume moth with recombination fraction (rf) value of 0.125 (12.7 cM of Kosambi function). The resistance specific fragment OPA09910 was cloned, sequenced and converted into a sequence characterized amplified region (SCAR) marker, SCOPA09942, which was also closely associated (10.3 cM) with the locus PPM1 with rf value 0.102. BLAST analysis with pigeon-pea genome sequence also confirmed its occurrence in CcLG02 (Scafseq.LG_V5.0fa) and contig 01597 (AFSP01.fsa1). This SCAR marker showed reasonable screening efficiency in the F2, F3, and BC1F1 lines, thus it can be used as genetic handle in marker-assisted introgression of the genomic fragment conferring plume moth resistance and screening of breeding lines in pigeon-pea.