Effects of Different Shading Condition on Dry Matter Accumulation and Distribution of Winter Wheat

Using shading field experiments,four treatments were conducted as follows:without shading(CK),60 percent shading(T1),40 percent shading(T2),20 percent shading(T3).Each organ dry matter weight of winter wheat(Triticum aestivum L.,Yangmai13)was observed at regular time,meanwhile dry matter accumulation and distribution responses were determined under different shading condition.With the effects of air temperature and combine solar irradiation factors,the models of dry matter accumulation and distribution responses of winter wheat were established.The results showed that temperature reducing and solar radiation hindered dry matter accumulation of winter wheat,especially for the root,stem and spike.Shading was serious negative effect on them.It was negative effect in the early period and be positive influence in late period for leaf.At the same time,it also influenced seriously distribution proportion of dry matter.Along with the change of effective accumulative temperature,dry matter accumulation and distribution of winter wheat under different shading condition all presented quadratic parabolic curve changes.With three factors(effective accumulative temperature,accumulative daily difference in temperature and solar radiation accumulation),the model simulated well dry matter accumulation and distribution of winter wheat under different shading condition,and could provide practical value for the growth analysis and production management to winter wheat growing.