双季连作晚稻免耕抛秧氮钾肥施用技术的研究

研究了不同氮钾施用量对免耕抛秧双季连作晚稻的产量效应。研究表明,增施氮肥可以促进分蘖的发生和叶面积的扩展,增加单位面积的有效穗数,但成穗率下降;增施钾肥可适当提高单位面积的有效穗数和成穗率;各施氮处理水稻根系活力和剑叶叶绿素含量均明显高于无氮处理;随着氮肥用量的增加,水稻干物质的积累量增加,而收获指数减少;等氮条件,增施钾肥对水稻干物质的积累基本没有影响,但提高了氮肥的吸收利用率;氮肥的吸收利用率开始随着施氮量的增加而提高,至中氮处理达最大值,氮肥的生理利用率和农学利用率均随施氮量的增加而降低;氮(N)、钾(K2O)肥用量分别为150 kg/hm2和160 kg/hm2时,免耕抛秧稻的效果最佳。

Studies on the techniques of nitrogen and potassium fertilizers application of no-tillage and east transplanting in double continuous cropping late rice

The yield effects of different nitrogen and potassium fertilizers application of no-tillage and cast transplanting in double continuous cropping late rice was studied.The results showed that application of fertilizer-N improved the rice tillering capability and leaf area index,increased the pructive panicle number and reduced the productive tiller percentage,increase of fertilizer-K approprio increased the pructive panicle number and the productive tiller percentage.The a-NA oxidation ability of rice root in late growth stage and content of chlorophyll in flag leaves after heading of N application treatments were higher than those of CK.The dry matter accumulation increased along with fertilizer-N rate increase,but the harvest index decreased;At the same N level,effect of increase of fertilizer-K application appropriately on the dry matter accumulation was low,while increased N-recovery efficiency.The N-recovery increased with N-application rate at first,amount to highest level at moderate N level,then decreased obviously at high N level.The fertilizer-N physiologyical efficiency and fertilizer-N agronomic efficiency decreased with fertilizer-N rate increase.The effect of no-tillage and cast transplanting rice was the along best when the N,K application rate were 150 kg/hm2 and 160 kg/hm2,respectively.