Cytological and microsatellite mapping of mutant genes for spherical grain and compact spikes in durum wheat

Two mutants for sphaerococcoid seed (MA 16219) and compact spike (MA 17648) were isolated from M-3 progeny of durum wheat cultivar, Altaiskaya Niva, mutagenized with chemical mutagens. The chromosomal locations of the genes involved were determined by the use of a complete set of D-genome disomic substitutions in durum cultivar, Langdon. The gene for sphaerococcoid grain, s(16219), was allelic to S2, located in the centromeric region of chromosome 3B in hexaploid wheat. The gene for compact spike, C (17648), was located on chromosome 5AL distal to the Q locus. Using microsatellite markers, C-17648 and awn inhibitor B1 were located in the F-2 of LD222 x MA17648. The gene order was Xbarc319-C-17648-Xgwm179-Xgwm126-Xgwm291-B1.