水肥耦合对温室无土栽培黄瓜氮代谢的影响

 以黄瓜‘中农19号’为材料，研究了温室无土栽培条件下水肥耦合对几种氮代谢酶及相关物质含量的影响。设3种单株灌水量水平：87 L（W1）、125 L（W2）、162 L（W3），3种单株施肥量水平：64 g（F1）、92 g（F2）、119 g（F3）。试验结果表明，灌水量处理对植株叶片硝酸还原酶（NR）、谷氨酰胺合成酶（GS）、谷氨酸合成酶（GOGAT）、谷氨酸脱氢酶（GDH）活性及硝态氮和可溶性蛋白质含量的正影响显著，在F1施肥水平下，W1的几种氮代谢指标高于W2和W3；在F2和F3施肥水平下，W2的灌水量水平最好。施肥量处理对NR、GS、GOGAT、GDH活性及硝态氮和可溶性蛋白质含量的正影响皆达到极显著水平，在相同灌水量水平下，F3 > F2 > F1。灌水量和施肥量2因素之间有显著的互作效应。从相关分析上看氮代谢酶活性及相关物质含量与黄瓜产量及果实中硝酸盐、游离氨基酸、可溶性蛋白质及可溶性糖含量之间呈显著的正相关。

Effects of Water and Fertilizer Coupling on Nitrogen Metabolism of Cucumber Under Soilless Culture in Greenhouse

Cucumber‘Zhongnong19’was used to investigate the effects of water and fertilizer coupling on several nitrogen metabolism enzymatic activities and related substance contents under soilless culture in greenhouse. Three single plant irrigation levels：87 L（W1），125 L（W2），162 L（W3），and three fertilization levels：64 L（F1），92 L（F2），119 L（F3）. The results showed that nitrate reductase（NR），glutamine synthetase（GS），glutamate synthase（GOGAT），glutamate dehydrogenase（GDH），nitrate nitrogen and soluble proteins content were remarkably influenced by different irrigation levels. Under the F1 level，several metabolism indexes of the W1 level were higher than other levels. Under the F2 level and F3 level，the W2 level was the best. Activities of NR，GS，GOGAT，GDH，nitrate nitrogen and soluble protein contents were remarkably affected by the fertilization levels，the order was F3 level，followed by F2 level and F1 level under the same irrigation levels. There was an obvious interaction between irrigation treatment and fertilization treatment. Correlation analysis showed that nitrogen metabolism enzymatic activities and related substance contents were positively correlated with yield，nitrate contents of fruit，free amino acid of fruit，soluble protein of fruit，soluble sugar of fruit.