水氮耦合对梨枣树光合特性的影响

通过常规灌水量(W1)和在梨枣树萌芽展叶期亏水量(W2)2个灌水水平与常规施氮量(N1)、2/3施氮量(N2)、1/2施氮量(N3)3个氮素水平的耦合试验,研究了不同水氮耦合对梨枣树光合特性的影响。结果表明,在常规水处理下,梨枣树的光合速率、蒸腾速率、气孔导度、净光合速率均随着施氮量的增加先增加后降低,而胞间CO2摩尔分数先减少后增加;在亏水处理下,除了胞间CO2摩尔分数处理N2高于处理N3外,其他光合特性指标均小于处理N3,但净光合速率基本相同。净光合速率最大值出现在常规水中氮处理(W1N2)。

Influence of Water and Nitrogen Coupling on Photosynthesis Characteristic of Pear-Jujube Tree

Influence on photosynthesis characteristic of Pear-Jujube tree was invested by two levels of conventional irrigation quantity(W1) and water losses at the burst to leafing stage(W2),and three nitrogen levels of conventional nitrogen(N1),two-thirds nitrogen(N2),1/2 of nitrogen(N3) coupling.The results showed that in conventional water treatments,photosynthetic rate,transpiration rate,stomata conductance,the net photosynthetic rate increased first then decreased with the increased amount of nitrogen,but pack CO2 concentration decreased firstly then increased;at rid treatments,in addition to intercellular CO2 concentration was higher in the high nitrogen treatment than the low nitrogen treatment,other photosynthetic characteristics index were less than the low nitrogen treatments,but net photosynthetic rate had no difference basically.Net photosynthetic rate maximum appeared in W1N2.