【摘要】 2019-2020年于河南省温县、原阳县和鹤壁市开展氮肥用量田间试验，研究秸秆还田下施氮对夏玉米子粒产量、品质、植物生理学形状及氮肥利用率的影响。结果表明，秸秆还田下施氮可显著提高夏玉米子粒产量，两者间呈“线性+平台”趋势。夏玉米子粒粗蛋白、粗脂肪和粗淀粉含量均随施氮量增加呈先升后降趋势，与不施氮处理相比，三者平均增幅分别为30.6%、30.4%、1.5%。生育期间夏玉米叶片SPAD值、FPAR值、叶片氮含量等理化指标均随施氮量增加而显著提高。夏玉米氮素收获指数随施氮量增加逐步降低，氮肥利用率和农学效率随施氮量增加呈先升后降趋势。综上，秸秆还田模式下合理施氮可显著提高夏玉米子粒产量、改善品质，增强各生育期生理活性以及提高肥料利用率，本试验条件下夏玉米适宜施氮量为230～260 kg/hm~2。更多还原

【Abstract】 Field experiments were conducted separately in Wenxian County in 2019, Yuanyang County and Hebi City in 2020, Henan Province, China. To study the effects of nitrogen application rates on grain yield, quality,physicochemical and N utilization characteristics of summer maize under straw returning mode, and provide a scientific basis for the optimal N application in this region. The results showed that the yield of summer maize increased with increasing N application rates in“ linear + platforms trends”. The crude protein, crude fat and crude starch in summer maize stopped increasing when the N application rate reached 240 and 280 kg/ha. Compared with the N0treatment, N application increased crude protein, crude fat and crude starch by 30.6%, 30.4%, and 1.5% on average in 2 years, respectively. The plant physiological indicators, such as the leaf SPAD value, FPAR and leaf nitrogen content increased with increasing N application rates. The N harvest index decreased gradually with the increase of N application rates, and the apparent utilization and agronomic efficiency increased first and then decreased with the increase of N application rate. Therefore, under the straw returning mode, reasonable nitrogen application can significantly increase summer maize grain yield, improve quality, enhance physiological activity at each growth stage, and improve fertilizer utilization efficiency. The recommended N application rates in the experimental area was 230-260 kg/ha.更多还原