Effects of Psy-A1, Ppo-A1, Ppo-D1, and Ta Lox-B1 Alleles on Flour Color of Xinjiang Wheats

The allelic variations on Psy-A1, Ppo-A1, Ppo-D1, and Ta Lox-B1 loci in 182 Xinjiang wheat varieties(lines) were tested using developed molecular markers that are associated with flour color. The effects of these alleles were analyzed in combination with phenotypes with the L*, a*, and b* values as well as the Wht data. On the view of a single gene, the allelic variation showed diverse effects on flour color. For L* value, the allelic effect was not significant. For a* value, the effect was Psy-A1 a Psy-A1b(P 0.01), Ppo-A1 b Ppo-A1a(P 0.05), and Ta Lox-B1 a Ta Lox-B1b(P 0.05). For b* value, the effect of Psy-A1 a was higher than that of Psy-A1b(P 0.01). As a result, the Wht value of Psy-A1 a was signlificantly lower than that of Psy-A1b(P 0.01). These results suggest that Psy-A1 significantly affects flour redness, yellowness and whiteness, whereas Ppo-A1 and TaLox-B1 only have significant effects on flour redness. A total of 12 allelic combinations were found on the four gene loci, with significant effect on a*, b* and Wht values(P 0.01) and slight effect on L* value(P 0.05). The combination Psy-A1b/PPOA1a/PPO-D1b/Ta Lox-B1 b had the highest Wht value and the lowest a* and b* values, and combination Psy-A1a/PPO-A1a/PPOD1b/Ta Lox-B1 a had the lowest Wht value and the highest a* and b* values. The average Wht value of total varieties(lines) tested was 86.86, and that of the released, winter, and spring varieties(lines) was 86.87, 86.42, and 87.32, respectively. Qingchun 5 should be used frequently as a promising parent in breeding programs for its excellent genotype and high flour whiteness. Our results indicate that Psy-A1 is a key gene for improving flour whiteness, and the frequency of Psy-A1 b should be promoted in Xinjiang wheats.