Identification of quantitative trait loci for seedling habit, grain color and cuticular wax from Tibetan semi-wild wheat (Triticum aestivum ssp. tibetanum)

Abstract

Aiming at detecting possible potentials of Tibetan semiwild wheat in breeding programs, we have identified several Quantitative Trait Loci (QTLs) for seedling habit, grain color and cuticular wax that are related to stress resistance such as cold resistance, pre-harvest sprouting and drought resistance using recombinant inbred line population derived from a cross between Tibetan semi-wild wheat (Q1028) and Zhengmai 9023 (ZM9023). A total of 17 QTLs were detected. Four QTLs were detected for seedling habits on chromosomes 2A, 2B, 2D, 6B, explaining 4.64%-26.40% of phenotypic variance. Of these, QTLs on chromosomes, 2A, 2B and 2D were stable across two growing years. Two stable QTLs were detected for grain color on chromosomes, 3A and 3B explaining 7.59%-12.81% of phenotypic variance. Five QTLs for spike wax, detected on chromosomes, 1B (2 QTLs), 2B, 2D and 5A explained 6.53%-13.20% of phenotypic variance, while six QTLs for stem wax were detected on chromosomes, 1A, 2B, 2D, 4A, 6A and 6B explaining 5.59%- 21.03% of phenotypic variance. The QTLs identified in this study broadened our understanding on Tibetan semi-wild wheat and laid the foundation for their further utilization in breeding program in order to improve the cold resistance, pre-harvest sprouting and drought tolerance.