不同氮肥种类和用量对川西蒙山茶品质的影响

Effect of Different Kinds and Amount of Nitrogen Fertilizer on Quality of Mengshan Tea in Western Sichuan

利用盆栽试验研究了尿素、硫酸铵、硝酸铵、碳酸氢铵和硝酸钙5种氮肥和用量对川西蒙山茶品质的影响。结果表明:肥料种类、肥料用量以及肥料种类与用量的交互作用对茶叶主要品质指标(可溶性糖除外)的影响极显著;不论施用何种氮肥,茶叶中的茶多酚、儿茶素和咖啡碱含量都有极显著的增加;各种氮肥用量为4g/盆时,茶多酚、儿茶素和咖啡碱含量较高;与施用其他种类的氮肥相比,尿素能极显著地提高茶叶中儿茶素和氨基酸的含量。施用硝态氮将能显著提高茶叶中硝酸盐和亚硝酸盐的含量,但随着硝态氮用量的增加,硝酸盐和亚硝酸盐的含量没有显著变化,而铵态氮和酰胺态氮对茶叶硝酸盐和亚硝酸盐含量基本没有影响。综合考虑春夏秋三季茶叶的品质,若单施一种氮肥,尿素最为合适,施用量为8g/盆左右。

A pot experiment was carried out in Sichuan agricultural university to check the effect of different kinds and amount of nitrogen fertilizer on quality of Mengshan tea in western Sichuan. Results were achieved as follows: Kinds, amount, kinds and amount of fertilizer all had significant effect on tea qualities(except soluble sugars).Contents of tea polyphenols(TP), catechins and caffeine were markedly increased by applying the five kinds of nitrogen fertilizer. TP, catechins and caffeine were higher in using 4 g/pot pure nitrogen than other amount. Catechins and amino acid were higher in (NH_4)_2CO treatment than other nitrogen fertilizer treatment. Content of NO_3^- and NO_2^- were significantly increased using NO_3-N fertilizer included NH_4NO_3 and Ca(NO_3)_2, but amount of NO_3-N fertilizer had no effect on content of NO_3^- and NO_2^-. The NH_4-N fertilizer and urea had few effect on content of NO_3^- and NO_2^-. Considering qualities of tea picked in spring, summer and autumn, urea was the best nitrogen fertilizer, and 8g/pot was the optimum amount.