130 wheat varieties are selected as materials to test the LOX activity, whiteness, yellowness, carotenoids content and RVA parameters, which are to be analyzed by variance analysis, correlation analysis, cluster analysis and classified according to the origins. The result shows there are highly significant variations in LOX activity from varieties; LOX activity is positively correlated with whiteness, and significantly and negatively correlated with yellowness. Cluster analysis applying longest distance method based on LOX activity clusters all the varieties or lines into three major groups. There are great differences between the averages of LOX activity from varieties. LOX activities are discussed in the application of nutritional quality improvement in wheat.
To test the roles of La3＋ on yield and quality of wheat for different end uses, experiments were conducted using split-plot design for different La3＋ treatments as main plot and different gluten types of wheat as subplot, by foliar spraying La3＋ at jointing stage and filling stage. The results showed that spraying 0.5–1.5 mmol/L La3＋ increased the yield and 1000-kernel weight of wheat of different gluten types. The protein content of strong-gluten wheat Wanmai 33 increased after spraying 0.5–1.5 mmol/L La3＋, which made it achieve the good quality standard of strong-gluten wheat, whereas its LOX and PPO activity reduced, the carotenoid content increased. These La3＋ treatments prolonged the storage period of grain, improved flour nutritional value and the food processing quality. Spraying 0.5–1.5 mmol/L La3＋ also increased flour peak viscosity of medium-gluten wheat Yangmai 158, as improving its starch properties. Spraying La3＋ significantly decreased flour water absorption rate of weak gluten type variety Wanmai 48 to meet the weak-gluten flour standard. The total pentosan content reduced at 1–1.5 mmol/L La3＋, which would be good for making biscuit. Results suggested that spraying appropriate concentration of La3＋ increased wheat yield and benefited wheat quality for different end uses.
