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

Abstract

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 whitegrained 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.

Improvement of preharvest sprouting resistance with <i>MOTHER OF FT AND TFL 1</i> + mutated <i>ABA 8ʹ-hydroxylase</i> in white-seeded durum wheat

“…In a previous study, we introduced two PHS-resistance genes and a QTL from common wheat (T. aestivum L.), namely an R-gene for red seed color, the MOTHER OF FT AND TFL 1 (MFT) gene, and Qphs-5AL, into 'Setodure' in different combinations to improve PHS resistance (Kato et al 2017). The R-gene, MFT, and QPhs-5AL all confer PHS resistance in common wheat under a rainy climate in Japan (Himi et al 2011, Kottearachchi et al 2008, Nakamura et al 2011. We found that a red-seeded durum wheat line with all three genes had PHS resistance similar to that of Japanese common wheat cultivars.…”