Effects of Water and Nitrogen Coupling in Winter Wheat on Leaves NRA,Plant Nitrogen Absorption and Yield

The experiment was conducted during 2006-2007 in field conditions on irrigation and Nitrogen Coupling effects on nitrate reductase activity,plant nitrogen absorption and yield of two different types of winter wheat Shixin733 and Shimai15.The result showed that the nitrate reductase activity of Shixin733 increased with the nitrogen amount,but the nitrate reductase activity of Shimai15 had the highest point among 180-240 kg nitrogen amount per hectare,decreased when too much or too less nitrogen.The nitrate reductase activity decreased when the nitrogen was too much or too less on the high soil containing water,increased with the increasing nitrogen on the low soil water content.Proper nitrogenous fertilizer could promote nitrogen absorption of the plant,but the anthesis irrigation improved the nitrate reductase activity of the flag leaves and grain yield,but remarkably reduced the whole nitrogen content of the grain and had less effection on the whole nitrogen absortption of the plant.On the experimental conditions,Shixin 733 had the highest yield when it was irrigated two times and feilizered 180 kg per hectare,Shimai 15 had the highest yield when it was irrigated two times and feilizered 60 kg per hectare.