The mixed inheritance analysis of polyphenol oxidase activities in winter wheat

Inheritance of PPO activity in 71 DH lines from the cross of ZhongYou 9507×CA9632 was investigated by the mixed major gene plus poly gene inheritance model of quantitative traits. The results showed that PPO activity in the cross was controlled by two major genes (the B 1 2 model). Heritability value of the major genes was estimated as 88.83%, while variance of environment was 11.17% in total variance. The estimated additive effects of the two major genes, d a and d b , were 2.432 and 1.084,respectively. The effect of d b was only about 44.60% of d a , indicating that the contributions to PPO activity of the two major genes was not equal in the cross. It is possible to breed new wheat cultivars with low PPO activity by choosing parents and handling segregating generation.