水肥耦合对露地松花菜氮代谢和产量的影响

摘要

[目的]探讨不同肥水条件下露地松花菜的氮代谢差异, 为其高产及合理肥水管理提供科学依据.[方法]以松花菜为研究对象, 对照组 (CK) 为当地传统肥水管理 (N:342kg/hm2, P2O5:212kg/hm2, K2O:284kg/hm2;大水漫灌) , 试验组使用滴灌系统, 采用二因素交互设计, 因素一为施肥量, 设3个梯度F1 (N:342kg/hm2, P2O5:212kg/hm2, K2O:284kg/hm2) 、F2 (80％F1) 、F3 (60％F1) ;因素二为灌水下限, 设3个梯度W1、W2和W3分别为田间最大持水量的80％、60％和40％.[结果]对照组 (CK) 与试验组F1W1、F2W1的硝酸还原酶 (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含量基本不显著;在试验组中施肥处理对松花菜叶片NR、GS、GOGAT、GDH活性及硝态氮和可溶性蛋白含量的影响极显著, 在相同灌水条件下, F1> F2> F3;灌水下限处理对松花菜叶片NR、GS、GOGAT、GDH活性及硝态氮和可溶性蛋白含量的影响也极显著, 在F1和F2施肥水平下, W1的灌水下限最为显著;在F3施肥水平下, W3的氮代谢指标高于W1和W2.同产量最相关的氮代谢指标为叶片中可溶性蛋白含量.[结论]综合分析表明F2W1 (N:274kg/hm2, P2O5:170kg/hm2, K2O:227kg/hm2;灌水下限:80％) 处理为本试验的最佳肥水组合.与传统肥水处理下的松花菜相比, 滴灌条件下水肥耦合处理的松花菜能更有效地利用水分和养分.在试验组中灌水和施肥之间有显著的交互作用, 且氮代谢酶活性及相关物质含量与松花菜产量之间呈显著的正相关.%[Objective]The objective of this study is to investigate the difference of nitrogen metabolism in loose-curd cauliflower under different fertilizer and water conditions and provide a theoretical basis for its high yield and suitable fertilizer and water management.[Method]The loose-curd cauliflower was treated with different fertilizer and water management patterns:CK group (local traditional management, N:342kg/hm2, P2O5:212kg/hm2, K2O:284kg/hm2;flood irrigation) and experimental groups which had two treatment factors of fertilization and irrigation.The fertilization was designed with 3 gradients:F1 (N:342kg/hm2, P2O5:212kg/hm2, K2O:284kg/hm2) , F2 (80％ F1) and F3 (60％ F1) .The irrigation was also with 3 gradients:W1 (80％ water holding capacity, WHC) , W2 (60％ WHC) and W3 (40％ WHC) .[Result]The results showed that the contents of nitrate reductase (NR) , glutamine synthetase (GS) , glutamate synthase (GOGAT) , glutamate dehydrogenase (GDH) , nitrate nitrogen and soluble proteins were remarkably influenced by fertilization levels (F1>F2>F3under the same irrigation levels) .Activities of NR, GS, GOGAT, GDH, nitrate nitrogen and soluble protein contents were also remarkably affected by the irrigation levels.Under F1 and F2 levels, several metabolism indexes in W1 group were higher than other levels.Under F3 level, W3 level was higher than W2 and W3 levels.The content of soluble protein in leaf showed the strongest relationship with yield.[Conclusion]Comprehensive analysis showed that F2W1 (N:274kg/hm2, P2O5:170kg/hm2, K2O:227kg/hm2;irrigation:80％ of WHC) was the best combination of fertilization and irrigation.There was an obvious interaction between irrigation treatment and fertilization treatment.The nitrogen metabolism enzymatic activities and related substance contents were positively correlated with yield.