Uptake And Transport Of Nitrogen, The Effect Of Nitrogenous Fertilizer On Their Nitrate Accumulation In Three Kinds Of Fruit Tree

With the development of environmental protection recently, increase demand for Green Quality Fruit give rise of attention to the nitrate proportion in the fruit. However, uptake and transport of nitrogen and nitrate accumulation in the fruit tree weren't nearly studied. Thus, studying process and factors of uptake and transport of nitrogen will give guidance to these work how to adapt reasonable fertilization means, select appropriate fertilizer types, determine the best time and improve the environmental conditions. In view of these, Experiment was conducted with the walnut, the kiwifruit and the grape which have the obvious bleeding to analyze and compare amino acid, nitrate nitrogen and ammonium nitrogen for studying the effect of nitrate accumulation and NRA of fruit tree under different nitrogenous fertilizer.Results are as follows:1. Experiment was conducted with the walnut, the kiwifruit and the grape for analyzing and comparing the content of free amino acid, nitrate nitrogen and ammonium nitrogen in bleeding sap of them, the results in two years showed: There were 12 to16 kinds of free amino acid in bleeding sap of them, and the contents were different with each other. In spring, the total amino acid content in bleeding sap of the walnut and the kiwi fruit were more than that of the grape. The results in two year showed the aspartic acid class amino acid biosynthesis was synthesized strongly in the kiwi fruit and the grape root system, and the glutanic acid class amino acid biosynthesis were the most powerfully synthesized in the walnut root system. Amino acid in the walnut and the kiwi fruit root system were more stably synthesized than those of grape. Content of nitrate nitrogen in the bleeding sap of the kiwifruit was highest, and that of the walnut was lowest. The content of ammonium nitrogen in bleeding sap of three kinds of fruit trees was all low.2. Different kinds of nitrogenous fertilizer have different influence to nitrate accumulation in fruit trees and NO3—accumulation at the different position of fruit trees. In the fruit and leaves, the tendency of Nitrate levers effecting nitrate accumulation came out:...