Study On The Regulating Effects Of Fertilizer Treatments On Wheat Quality And Its Physiological Basis

Fertilizer measure is one of the most effective cultivation ways to regulate wheat quality. In this experiment all the fertilizer factors (different N, P. K, S combination and the different nitrogen application phases) which have an effect on wheat quality were designed in the same field, on the condition that fertilizer quantity was the same and applied to the same high quality wheat varieties, Zhongyou 9507. The main objective was to compare the different effects of fertilizer treatments on wheat quality in the same experiment. At the same time, physiological basis for wheat quality was discussed, and evaluation methods of wheat quality were analyzed. The effect of sulphur fertilizer on the quality and yield of different protein content of wheat varieties was investigated further when it was applied additionally to the conventional fertilizer measure. The main results are as below:1. The nitrate reductase activity, chlorophyll content and nitrogen content in the flag leaf showed significant positive correlation with wheat quality after the emergence of flag leaf. After heading period a positive correlation between nitrogen content of vegetative organs and wheat quality was evidently presented. This result is valuable to predict the wheat quality.2. Different fertilizer treatments showed notable effects on the physiological parameters and wheat quality'. In comparison with the basic fertilizer treatment, top-dressing fertilizer treatment of nitrogen fertilizer increased NRA activity, Chl content in flag leaf and N content in flag leaf and vegetative organs to some degree, and top-dressing in the jointing and flowering stage showed best effect on physiological parameters in the late stage of wheat. Top-dressing nitrogen in twice significantly increased prolamin content, total protein content, dough rheological characters and gluten content, and was regarded as the best fertilizer treatment to improve wheat quality.3. Different quality parameters were analyzed systematically to confirm their role in evaluating wheat quality. Sedimentation value and wet gluten content are positively correlated to total protein content, the same as dry gluten to the storage protein content. While the flour yield was negatively correlated to the ratio of prolamin and glutenin. And all the relations were the closest ones among the parameters. The ratio of prolamin and glutenin, 1000 grain weight, dry gluten content were valuable parameters to predict the bread-making quality, and the ratio was more reliable than the other two parameters.4. When sulphur fertilizer was applied additionally to conventionally fertilized field, the nitrogen content in vegetative organs and kernel were increased and the content of prolamin content and total protein content were increased significantly, too. Different genotype showed different reaction to sulphur fertilizer.