秸秆还田配施腐熟剂对水稻产量及钾肥利用率的影响

Effect of straw returning with decomposing inoculants on grain yield and potassium fertilizer utilization efficiency of rice

为探明秸秆还田配施腐熟剂对水稻产量及钾素利用率的影响,提高秸秆还田利用效率。通过田间试验,对比分析了4个处理[配方施肥无钾肥对照(N-P_2O_5-K_2O=270-90-0 kg·hm^(-2))+秸秆不还田+不施用腐熟剂(T1)、配方施肥(N-P_2O_5-K_2O=270-90-135 kg·hm^(-2))+秸秆不还田+不施用腐熟剂(T2)、配方施肥(N-P_2O_5-K_2O=270-90-135 kg·hm^(-2))+秸秆还田+不施用腐熟剂(T3)和配方施肥(N-P_2O_5-K_2O=270-90-135 kg·hm^(-2))+秸秆还田+腐熟剂(T4)]的水稻钾素吸收累积量、水稻产量及钾素利用效率。结果表明:(1)与配方施肥相比,秸秆还田处理使水稻抽穗期钾素总累积量和净吸收量分别提高了15.3%和13.9%(P<0.05);水稻成熟期钾素含量提高了5.5%,钾素总累积量和净吸收量分别提高了21.5%和50%;(2)在相同的施钾水平下,秸秆还田与秸秆还田配施腐熟剂处理对水稻均有显著的增产效果,产量增量分别为649.7和1 110.5kg·hm^(-2),增幅分别为6.4%和10.4%;(3)秸秆还田配施腐熟剂处理的钾肥贡献率、农学利用率、偏生产力和吸收利用率较配方施肥分别比对照提高了9.2%、45.5%、10.4%和39.0%(P<0.05)。可见,秸秆还田配施腐熟剂可增加水稻钾素吸收量,提高钾肥利用效率,实现增产效果。

Straw returning with decomposing inoculants was known to increase crop yield and promote soil fertility by accelerating straw decomposition and nutrient release of crop straw.A field experiment was conducted to investigate and compare the potassium accumulation,utilization efficiency and yield of rice under 4 treatments,including formula fertilization without potassium（N-P2O5-K2O = 270-90-0 kg·hm^-2）（T1）,formula fertilization（N-P2O5-K2O = 270-90-135 kg·hm^-2）（T2）,formula fertilization（N-P2O5-K2O = 270-90-135 kg·hm^-2） ＋ straw returning（T3）,formula fertilization（N-P2O5-K2O = 270-90-135 kg·hm^-2） ＋ straw returning ＋ decomposing inoculants（T4）.The results showed that：（1） the total and net accumulation of potassium in rice under straw returning treatment increased by 15.3% and 13.9%,respectively,compared to formula fertilization treatment at the heading stage.While the content,the potassium content in rice were increased by 5.5%,total and net accumulation of potassium in rice were increased by 21.5% and 50%,respectively,at the maturing stage.（2） Compared with the treatments of formula fertilization,treatments of straw returning with and without decomposing inoculants increased rice yields by 6.4% and 10.4%,respectively.（3） In comparison to formula fertilization,the contribution rate,agronomic use efficiency,partial fertilizer productivity and absorption efficiency of potassium fertilizer in rice under straw returning and decomposing inoculants application increased by 9.2%,45.5%,10.4% and 39.0%,respectively.In conclusion,the results of this study indicated that straw returning with decomposing inoculants could increase the absorption and utilization efficiency of potassium as well as grain yields of rice,which might supply theoretical basis for straw application and fertilizer reduction.