关键词: 杀菌剂, 杀菌剂, 葡萄灰霉病, 毒力测定, 联合毒力

Abstract: Aiming at improving the quality of fresh tea leaves, effects of shading on the main nitrogen compounds of fresh tea leaves, including caffeine, soluble protein and free amino acids, were investigated. The tea plants were treated with varied levels of shading (0%, 33%, 42%, 51%, 53%, 70% and 89%) and varied time (12, 21 and 65 days), then the contents of main nitrogen compounds in fresh leaves were measured. Compared with the control group (i.e., 0% shading), no significant difference was observed in caffeine content in fresh leaves that treated with 65 days and 42% shading, but the caffeine content increased in other treatments. For example, the caffeine content in fresh tea leaves with treatment of 89% shading was 16.95% and 54.41% higher than that in control groups at 12 and 21 days, respectively. Besides, when the fresh tea leaves were treated with 53% or 51% shading for 12 days, the content of soluble protein was 13.91% and 17.88% higher than that in control group, respectively. Except 33% shading treating group, the total amounts of free amino acids increased after 12 days, and that of the group with 70% shading increased by 22.31% compared with the control. Therefore, in early spring time, fresh tea leaves treated with 50%-70% shading could increase the contents of main nitrogen compounds.