有机-无机肥不同配施比例对水稻氮素吸收利用率的影响

在等氮量替代条件下,以武运粳29号为供试材料,设置不施氮肥(M0)作为空白对照,单施化肥(M1),以及25%有机肥(M2)、50%有机肥(M3)、75%有机肥(M4)、100%有机肥(M5)替代化肥6个处理,研究有机-无机肥不同配施比例对水稻氮素吸收利用率的影响。结果表明:(1)在水稻生育前期,化肥施用比例高的处理土壤速效氮含量高;到水稻生育后期,有机肥替代比例高的处理土壤速效氮含量高。(2)50%有机肥替代化肥水稻产量最高。(3)50%有机肥替代化肥能够显著提高水稻的氮素累积量。(4)100%有机肥替代化肥处理水稻氮素籽粒生产效率最低,单施化肥处理水稻氮素籽粒生产效率最高。(5)50%有机肥替代化肥,在保证水稻高产的同时,显著增加水稻氮素累积量,并使水稻氮肥农学利用率、氮肥吸收利用率、氮肥偏生产力均得到明显提高。说明提高水稻氮素吸收利用效率,在等氮量替代条件下,50%有机肥替代化肥是一种相对适宜的比例。

Effect of different organic inorganic fertilizers combination ratio on nitrogen use efficiency of rice

Under the equivalent nitrogen substitution condition, a field experiment was conducted in 2015 to investigate the effect of different organic-inorganic fertilizers combination ratio on nitrogen use efficiency of rice in a wheat-rice double cropping system, with the rice cultivar of Wuyunjing 29 as tested material. Six treatments, including no nitrogen fertilizer application (M0), single chemical fertilization application (M1), and applying 25% organic fertilizer (M2), 50% organic fertilizer (M3), 75% organic fertilizer (M4), 100% organic fertilizer (M5) as substitute of chemical fertilizer, were designed. The results showed that: (1) the available nitrogen content of soil was higher with high proportion of chemical fertilizer appli-cation treatments in rice early growth stage, but it was higher with high proportion of organic fertilizer application treatments in rice late growth stage. (2) The rice yield was the highest in 50% organic fertilizer substitute treatment (M3). (3) 50% or-ganic fertilizer substitute treatment (M3) significantly increased nitrogen accumulation of rice. (4) In terms of nitrogen use efficiency for grain yield, 100% organic fertilizer substitute treatment (M5) was the lowest, single chemical fertilization ap-plication (M1) was the highest. (5) 50% organic fertilizer substitute treatment (M3) ensured the high yield of rice, sig-nificantly increased nitrogen accumulation of rice, and obviously improved agronomic efficiency, recovery efficiency, partial factor productivity of nitrogen fertilizer at the same time. On the whole, 50% organic fertilizer substitute treatment was a rela-tively suitable ratio of organic fertilizer to replace chemical fertilizer under the equivalent nitrogen substitution condition.