Effect Of Spraying Nitrogen On The Growth Characteristics, Yield And Quality Of Wheat

The excellent breeds and the reasonable models of cultivation and management measures and the suitable of fertilization level are necessary to obtain high yield of wheat. In numerous elements of the nutrition that affect the wheat, the nitrogen is one of the most important factors that can impact the yield and quality of wheat. The experiment studies the effect of foliar nitrogen application on the growth characteristics, dynamic change of grain filling, yield, quality and senescence on wheat. Using Pubing79 and Nongda 1108 as test material. The main results were as follows:1. With the increase of concentration of spraying nitrogen, the SPAD of the flag leaf, the leaf area, the photosynthetic rate and transpiration rate will be increased. There are significant differences between the diversity concentrations of spraying nitrogen on the SPAD value of flag leaf. When the concentration of spraying nitrogen increased to 2.5%, the SPAD of the flag leaf, the leaf area, the photosynthetic rate and transpiration rate will fall.2. The grain filling can be divided into slow, fast, slow according to the grain filling rate. When the concentration of spraying nitrogen below 2.5%, the biggest grain filling rate, the average grain filling rate and the average grain filling rate at the rapid increase period were significantly higher than control study. When the concentration of spraying nitrogen reached 2.5%, with the improvement of concentration of spraying nitrogen, the biggest grain filling rate, the average grain filling rate and the average grain filling rate at the rapid increase period will decreased. Compared with control study, the appear of the biggest grain filling rate had ahead of time in the treatments of spraying nitrogen. Also the duration time at the rapid increase period will be decreased.3. When the concentration of spraying nitrogen increased to 2.5%, with the improvement of concentration of spraying nitrogen, the yield, thousand grain weight and grain number per spike will be raised. When the concentration of spraying nitrogen increased to 2.5%, these targets will be reduced.4. After spraying nitrogen on two varieties of wheat, the Test weight, Hardness, Protein, Wet gluten and Absorption were increased firstly and the decreased. When the concentration of spraying nitrogen was 2.0%, these indexes reached the maximum value. With the increased of concentration, these indexes will increased. When the concentration of spraying nitrogen reached to 2.0%, these indexes will cut down. Zeleny and Stretch area will got the maximum when the concentration of spraying nitrogen was 1.5%. These indexes will cut down after the concentration of spraying nitrogen exceeded 1.5%.5. The activities of SOD and POD of flag leaf were presented single peak curve in two varieties of wheat, and were increased firstly and the decreased. The activity of SOD was achieve the maximum in the date of 14 May; while the activity of POD was achieve the maximum in the date of 20 May. These enzymes were increased with the increased of concentration of spraying nitrogen, and will decreased after the concentration of spraying nitrogen above 2.5%.