中文摘要：

为探索氮肥运筹对免耕条件下水稻根系生长以及对根际土壤特性、产量的影响,以金优253为材料进行试验。结果表明：平衡施肥显著提高单株根系干重、根长、单株生物量、根半径、单株根表面积、根长密度及根系活力,实收单产高于重穗肥和重基肥处理,且与重基肥差异达95%的显著水平,主要是有效穗数、结实率的增加。平衡施肥显著提高0～10cm土层的0～2mm根际土壤有机质、碱解氮含量及脲酶、蔗糖酶活性。因此平衡施肥能明显促进免耕水稻根系生长和有效穗数的增加,对提高水稻产量具有促进作用。

英文摘要：

The effect of nitrogen application modes on root growth,rhizosphere soil characteristics and rice yield under no-tillage and cast transplanting rice was studied.The results showed that balanced fertilization made obvious influ-ence on no-tillage and cast transplanting rice root growth,and physiology.The rice shoot dry weight and biomass per plant,root number,root density,root activity of balanced fertilization were higher than other treatments,the differ-ences were significant in rice later growth.However,there were no significant differences in root length.Balanced fer-tilization increased spike lets per panicle and seed set.Balanced fertilization significantly increased 0-10 cm soil layers organic,available nitrogen and urease activity of 0-2 mm rhizosphere soil in rice late growth.Therefore,it can been concluded that balanced fertilization acquired higher grain yield by improving rhizosphere soil,promoting root growth and increasing effective panicles.