施氮量和直播量对超级杂交稻五丰优T025产量及养分利用率的影响

Effects of Nitrogen Rate and Direct-seeding Rate on Yield and Nutrient Use Efficiency of Super Hybrid Rice Wufengyou T025

采用两因素裂区设计,在典型的红壤稻田研究施氮量和直播量对超级杂交稻五丰优T025群体茎蘖动态、产量和养分吸收利用的影响。结果表明,不同施氮量处理对五丰优T025的群体分蘖数和有效穗影响较小,但不同直播量处理间的群体分蘖数和有效穗差异显著。随着播种量增加,有效穗和产量相应增加,以施氮量180 kg/hm^2、播种量37.5 kg/hm^2的处理组合产量最高,达10.65 t/hm^2。施氮有利于五丰优T025对氮、磷、钾的吸收,但随施氮量的增加,氮磷钾收获指数和氮肥利用率降低。合理增加直播量、减少施氮量可保证五丰优T025的产量,同时提高其氮肥利用率。

The effects of nitrogen rate and direct-seeding rate were studied on the population tillering dynamic,grain yield and nutrient use efficiency of Wufengyou T025,a super hybrid rice combination,with the two-factor split plot design in typical red soil paddy fields. The results showed that the treatments of N rate（ 0 ~ 270 kg/hm2） had little influence on the population tiller number and the number of productive panicles while the treatments of direct-seeding rate（ 22. 5 ~ 45. 0 kg/hm^2） had significant influence on the population tiller number and the number of productive panicles. The number of productive panicles and grain yield increased with the increase of seeding rate.The treatment of N3D3,with the N rate at 180 kg/hm2 and the seeding rate at 37. 5 kg/hm^2,reached the highest yield at 10 653. 3 kg/hm^2. Application of nitrogen fertilizer enhanced the uptake of N,P and K for Wufengyou T025,but with the increase of N rate,the harvest indices of N,P and K and the nitrogen use efficiency decreased.Therefore,higher yield and nitrogen use efficiency could be achieved by reasonably increasing direct-seeding rate but decreasing nitrogen rate for Wufengyou T025.