LINKAGE MAPPING OF QUANTITATIVE TRAIT LOCI CONTROLLING SEED WEIGHT INPEA (PISUM-SATIVUM L)

Quantitative trait loci (QTLs) affecting seed weight in pea (Pisum sat ivum L.) were mapped using two populations, a field-grown F-2 progeny of a cross between two cultivated types ('Primo' and 'OSU442-15') and glasshouse-grown single-seed-descent recombinant inbred lines (RILs) f rom a wide cross between a P. sativum ssp. sativum line ('Slow') and a P. sativum ssp. humile accession ('JI1794'). Linkage maps for these c rosses consisted of 199 and 235 markers, respectively. QTLs for seed w eight in the 'Primo' x 'OSU442-15' cross were identified by interval m apping, bulked seg regant analysis, and selective genotyping. Four QTL s were identified in this cross, demonstrating linkage to four interva ls on three linkage groups. QTLs for seed weight in the 'JI1794' x 'Sl ow' cross were identified by single-marker analyses. Linkage were demo nstrated to four intervals on three linkage groups plus three unlinked loci. In the two crosses, only one common genomic region was identifi ed as containing seed-weight QTLs. Seed-weight QTLs mapped to the same region of linkage group III in both crosses. Conserved linkage relati onships were demonstrated for pea, mungbean (Vigna radiata L.), and co wpea (V. unguiculata L.) genomic regions containing seed-weight QTLs b y mapping RFLP loci from the Vigna maps in the 'Primo' x 'OSU442-15' a nd 'JI1794' x 'Slow' crosses.