不同施氮比例对直播水稻产量的影响

The Effects of Different Nitrogen Ratios on the Yield of Direct-seeding Rice

为了探讨精量机条播和人工撒播水稻产量形成的规律,明确直播稻最适宜的氮肥运筹比例,特做了不同前后氮肥比例对精量机条播和人工撒播水稻产量的影响。试验结果表明:机条播的最优氮肥运筹比例为7∶3,人工撒播的最优氮肥运筹比例为6∶4;精量机条播比人工撒播产量高的主要优势在于有效穗不减少,而穗型变大;后期氮肥比例增加促进二次枝梗的数量,提高每穗总粒数和每穗实粒数;适宜的氮肥运筹比例能明显促进抽穗期、成熟期的干物质积累量。

The paper investigates the laws of rice yield formation with precision machine drilling and artificial sowing,clarifies the most suitable nitrogen fertilizer ratio for direct-seeding rice, and explores the effects of different nitrogen proportions on the yield of rice with precision ma-chine drilling and artificial sowing.The optimum nitrogen proportion with machine drilling is 7∶3,and that with artificial sowing is 6∶4.Compared with artificial sowing,the advantages of precision machine drilling lie in higher yields without reducing the effective panicle,but getting larger panicle type.With the late increase of nitrogen proportion through the promotion of the number of secondary branches,the total grain number and the actual grain number per panicle increases.The suitable nitrogen proportion can promote dry matter accumulation at heading and maturing stages.