深松与控释尿素耦合对夏玉米穗位叶衰老代谢及籽粒产量的影响

试验采用裂区设计，以耕作方式为主区，施肥方式为副区，研究田间不同耕作方式下，施肥方式对玉米穗位叶衰老代谢及籽粒产量的影响。结果表明，相同耕作方式下，控释尿素处理可显著提高植株的总吸氮量，在玉米吐丝后光合叶面积指数显著高于常规尿素处理（P〈0．05），控释尿素处理也可显著提高玉米穗位叶SOD、POD和CAT活性，增加可溶性蛋白含量，降低MDA积累量。因而，该控释尿素处理对籽粒灌浆速率的提高效果显著。相同施肥方式下，深松处理可以提高植株水分利用效率，有利于玉米产量的提高。深松与控释尿素耦合满足了植株对水分氮素吸收利用的时空需求，显著提高了玉米吐丝后的光合叶面积指数、抗氧化酶活性、灌浆速率和干物质积累量，延缓穗位叶衰老效果最佳，籽粒产量最高。

Coupling Effects of Subsoiling and Controlled - Release Urea on Ear Leaf Senescence Metabolism and Grain Yield of Summer Maize

The split block design was adopted to study the effects of nitrogen application modes on ear leaf senescence metabolism and grain yield of maize under different tillage methods. The results showed that under the same tillage method, the controlled - release urea could significantly increase the total absorption a- mount of single plant, leaf area index after silking, and the SOD, POD and CAT activities and soluble protein content in ear leaves, but decrease the MDA content. So, the application of controlled - release urea had sig- nificant influences on increasing grain - filling rate. Under the same nitrogen application mode, subsoiling could increase the water use efficiency of single plant, and was benefit for the increase of maize yield. Subsoi- ling coupling with controlled - release urea could meet the need of plants to water and nitrogen, increase the leaf area index after silking , antioxidant enzyme activities, grain filling rate and dry matter accumulation siR-nificantly, so the senescence of ear leaf could be delayed better and the highest grain yield could be obtained.