穗肥氮占比对机穴播杂交粳稻产量形成及产量的影响

Effects of nitrogen ratio of panicle fertilizer on yield formation and yield of mechanical hill-drop sowing Japonica hybrid rice

研究了氮素基蘖肥与穗肥不同比例对机穴播杂交粳稻‘花优14’产量及产量构成因素的影响。结果表明:在总氮300 kg/hm^2条件下,基蘖肥与穗肥氮素比例为6∶4处理的水稻产量最高,达到(12 145. 92±277. 35) kg/hm^2,极显著高于其他处理;基蘖肥与穗肥氮素比例为7∶3处理的水稻产量分别显著和极显著高于比例为8∶2和9∶1的处理。产量构成因素对产量的贡献为有效穗数>穗粒数>结实率>千粒重。增加穗肥氮占比能有效提高穗粒数和每穗结实率,降低有效穗数,但对千粒重影响较小。由穗肥氮占比与产量拟合方程(Y=-9 142. 21x2+12 178. 18x+7 779. 51,R2=0. 9066**)解析可知,穗肥氮占比超过基蘖肥的0. 67倍时,水稻产量下降。研究表明:杂交粳稻‘花优14’机穴播在纯氮300 kg/hm^2条件下,在穗肥为基蘖肥的0. 43—0. 67倍、确保有效穗数(332. 25×104/hm^2)基础上,可通过增加穗粒数、提高结实率和稳定粒重达到高产目标。

The effects of different ratios of basic tillering fertilizer to panicle fertilizer(RBP)on yield and yield components of mechanical hill-drop sowing Japonica hybrid rice ‘Huayou 14’ were studied.The results showed that under the condition of total nitrogen 300 kg/hm^2,the yield of rice treated with RBP of 6 ∶4 was the highest,reaching(12 145.92±277.35)kg/hm^2,which was significantly higher than that of other treatments.The yield of rice treated with RBP of 7 ∶3 was significant and extremely significant higher than that of treatment with RBP of 8 ∶2 and 9 ∶1,respectively.The contribution of yield components to yield was in the order of effective panicle number>grain number per panicle>seed setting rate>1 000-grain weight.Increasing the nitrogen ratio of panicle fertilizer could effectively increase the grain number per panicle and seed setting rate per panicle,and reduce the effective panicle number,but had little effect on the 1 000-grain weight.According to the fitting equation ( Y =-9 142.21 x ^2+12 178.18 x +7 779.51, R^2 =0.9066 ) of panicle fertilizer and yield,the rice yield decreased when the nitrogen ratio of panicle fertilizer exceeded 0.67 times of basic tillering fertilizer.In summary,under the condition of total nitrogen 300 kg/hm^2,on the basis of 0.43-0.67 times of panicle fertilizer as basic tillering fertilizer and ensuring the effective panicle number(332.25×10^4hm^2),the goal of high yield of ‘Huayou 14’ was achieved by increasing the grain number per panicle,seed setting rate and stabilizing the grain weight.