施氮量对茶树生长及叶片光合特性的影响

Effect of Nitrogen Application Rate on the Growth and Leaf Photosynthetic Characteristics of Tea

采用水泥池培育的方法,研究了不同氮肥施用量对茶树生长和叶片光合特性的影响。试验设置4个施氮水平,分别为0kg N/hm2（CK）、112.5 kg N/hm2（N1）、225 kg N/hm2（N2）和450 kg N/hm2（N3）。结果表明：施氮显著促进茶树生长,施氮处理茶叶产量比CK显著提高116.98%～141.51%（P〈0.05）,但施氮处理间差异不显著（P〉0.05）;施氮处理茶树叶片叶绿素总量提高30.56%～72.67%,类胡萝卜素含量降低13.37%～29.74%,并与CK差异显著（P〈0.05）;施氮处理茶树叶片净光合速率比CK显著提高14.88%～17.26%（P〈0.05）,但施氮处理间差异不显著（P〉0.05）;氮肥施用提高茶树叶片气孔导度、蒸腾速率和水分利用效率。适量的施氮可提高茶树叶片叶绿素含量、提高光合速率,促进茶树生长和茶叶产量提高;但随着氮肥施用量的增加,单位氮肥对茶树生长的促进效应降低。

Effects of nitrogen application rate on the growth and leaf photosynthetic characteristics of tea by the cement pond cultivation experiment were studied in the paper. There were four treatments of N application, 0（CK）, 112.5（N1）, 225（N2）, 450（N3）kg/hm2, respectively. The results showed that nitrogen application significantly promoted tea growth, and the tea productions of nitrogen application treatments increased significantly than CK from 116.98% to 141.51%（P〈0.05）, but there were no significant difference（P〈0.05）in the 3 treatments. The total chlorophyll contents of tea leaves in 3 N application treatments increased from 30.56% to 72.67%, the carotenoid contents in which decreased from 13.37% to 29.74% and with significant difference to CK（P〈0.05）. The net photosynthetic rates of tea leaves in 3 N application treatments increased significantly from 14.88% to 17.26%（P〈0.05）than CK, however there were no significant difference（P〈0.05）in the N treatments. So it indicated that appropriate N application rate could improve the chlorophyll contents, net photosynthetic rates, growths and productions of tea, but the effects of promotion of unit N application rate decreased with the higher N application rate.