Effect Of Applying Copper And Zinc On The Quality Of Mengshan Tea

Fertilization was one of the most effective cultivation ways to regulate tea quality. Four years old Mengshan tea 213 was chosen as the research subject, under potted plant experiment, effects under two applying methods (the soil application and leaf surface spraying) and different application quantities and the combined treatment of Copper(CuSO₄·5H₂O)and Zinc(ZnSO₄·7H₂O)on tea quality were studied. The main purpose of this study is to provide a theoretical basis for improving the tea quality. Tea was picked out to determine content of amino acid, tea polyphenol, caffeine, soluble sugar of leaves. The maim results are as below:(1) Effect of applying copper on tea qualityIt had been demonstrated that the application of copper fertilizer had a significant effect on contents of amino acid, tea polyphenol, caffeine, soluble sugar in tea. Even more, applying appropriate copper has a significant simulative effect on content of amino acid, tea polyphenol, caffeine, soluble sugar in tea. By comparison, the soil application made the content of amino acid increased by 9.338%, the tea polyphone by 11.156%, the caffeine by 8.427% and the soluble sugar by 29.812%, while leaf surface spraying application made the content of the amino acid increased by 47.065%, the tea polyphone by 16.839%,the caffeine by 16.039% and the soluble sugar by 25.257%.But applying excessive copper has a negative effect on tea quality. The experiment showed when the soil applying copper fertilizer was about 8mg/kg or leaf surface spraying was about 250mg/l the average quantities of the amino acid, the caffeine, the tea polyphone and the soluble sugar were higher respectively and their integrated proportion was proper, and then the quality of tea would reach its best comparatively.(2)Effect of applying zinc on tea qualityIt had been demonstrated that the application of zinc fertilizer had a significant effect on contents of amino acid, tea polyphenol, caffeine, soluble sugar in tea. Applying appropriate zinc has a significant simulative effect on tea qualities. By comparison, the soil application made the content of amino acid increased by 26.792%, the tea polyphone by 9.406%, the caffeine by 11.913% and the soluble sugar by 19.573%, while leaf surface spraying application made the content of the amino acid increased by 40.495%, the tea polyphone by 9.543%,the caffeine by 11.015% and the soluble sugar by 16.198%.Applying zinc of the right quantity will improve the tea quality, but excessive applying has a negative effect on tea quality. The experiment showed when the soil applying zinc fertilizer was about 14mg/kg or leaf surface spray was about 500mg/l, the average quantities of the amino acid, the caffeine, the tea polyphone and the soluble sugar were higher respectively and their integrated proportion was proper, and then the quality of tea would reach its best comparatively.(3) Effect under the combined treatment of copper and zinc on tea qualityThe combined treatment of copper and zinc had a significant effect on tea quality.The zinc concentration play a major role to the amino acid and caffeine in tea; and the copper concentration play a major role to the tea polyphenol and soluble sugar in tea. Tea polyphenol and soluble sugar in tea increased according to applying copper, amino acid and caffeine in tea increased according to applying zinc. The combined treatment of copper and zinc will improve the tea quality.The results showed that, when copper concentration of treating was 100mg/l and zinc concentration was 500mg/l, the interactive effects of the caffeine were highest. When copper concentration of treating was 100mg/l and zinc concentration was 1000mg/l, the interactive effects of the amino acid and the soluble sugar were highest. When copper concentration of treating was 500mg/l and zinc concentration was 500mg/l, the interactive effects of tea polyphenol were highest.(4) Effect of applying copper and zinc on copper and zinc contents of the teaDifferent copper applying methods have different effects on cooper contents of the tea.The copper contents of the tea were significantly enhanced with increasing concentration by leaf surface spraying, while it had not obvious effect by the soil application. Either soil application or leaf surface applying, the zinc fertilization had a significant effect on zinc contents of tea, which were significantly enhanced with increasing concentration of zinc. It would improve the copper contents of the tea by applying copper and zinc, but which would decrease the zinc contents.The paper analyses and compares several treatments that have effect on tea's qualities, which will provide theoretical basis for the improvement of fertilization ways of tea product, tea qualities, and the execution of planting; At the same time, it will provide theoretical reference for keeping and upgrading biological environment and agrarian quality of Mengshan tea product basis.