Identification of Grain Dormancy QTLs in a White-Grained Wheat Population Derived from ‘Zen’ x ‘Spica’ Cross

White-grained wheat is usually more susceptible to preharvest sprouting (PHS). Accumulation of color independent grain dormancy QTLs is one of the promising ways of developing PHS tolerance in white-grained wheat. A white grained recombinant inbred line (RIL) population was developed from a cross between high dormant Japanese red grained wheat, 'Zenkoujikomugi' ('Zen'), and a white cultivar 'Spica'.  White-grained RILs demonstrated a severe variation proving that many genes have involved in maintaining grain dormancy. Hence, to identify those dormancy QTLs of 'Zen' x 'Spica', whole genome was assessed with SSR and EST markers. Five novel grain dormancy QTLs, linked with Xwocs207, Xcfa2163, Xbarc243, Xbarc44 and Xgwm577 markers were detected located on chromosomal arms 3BS, 5AL, 5BL, 5DL and 7BL, respectively. In all instances, allele contributed to comparatively higher dormancy was derived from 'Zen'. The QTL linked with Xwocs207 marker appeared to be extremely effective, stable and reliable. Usually QTLs rendering minor effects were difficult to be detected if the phenotypic variation of the population was affected by major red color genes. In the present study, since only the white-grained RILs were used, minor QTLs were also able to be investigated.

Key words: Grain dormancy QTLs; EST markers; SSR markers; Preharvest sprouting; White-grained wheat

DOI: 10.4038/tare.v11i0.1768

Tropical Agricultural Research and Extension Vol.11 2008 pp.1-6