Mapping of loci controlling phenological traits in durum wheat under drought stress and non-stress conditions using SSR markers

In this experiment, markers linked to the gene(s) controlling days to heading, days to anthesis and days to maturity were identified in a segregating population of 151 F3 and F4 families derived from the cross between Oste-Gata as drought tolerance and Massara-1 as susceptible durum wheat genotypes. The traits were assessed in field trails in two environmental conditions in 2003 and 2004 cropping cycles. From 200 markers screened in this study, 30 markers which were polymorphic distributed on different wheat chromosomes, except 2A, 4A and 6B.. Based on single marker analysis, Xgwm148-2B and Xwmc45-7A showed association with days to heading under two environmental conditions and explained 19% of the total phenotypic variation. For days to maturity, Xcfa2114-6A closely associated with other traits under stress and non-stress conditions. The presence of markers that were exactly located at the same regions of chromosomes reflected high correlation between traits. Composite interval mapping identified 3, 2 and 2 QTLs for days to heading, days to anthesis and days to maturity, respectively. These QTLs were located on chromosome 2B and 3B for days to heading and days to antheisis and 3B and 5A for days to maturity, respectively. These QTLs could explain about 10% of phenotypic variation of phenological traits.