秸秆还田配施腐熟剂对水稻产量及钾肥利用率的影响

摘要

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-P2O5-K2O=270-90-0 kg·hm-2) +秸秆不还田+不施用腐熟剂 (T1)、配方施肥 (N-P2O5-K2O=270-90-135 kg·hm-2) +秸秆不还田+不施用腐熟剂 (T2)、配方施肥 (N-P2O5-K2O=270-90-135 kg·hm-2) +秸秆还田+不施用腐熟剂 (T3) 和配方施肥 (N-P2O5-K2O=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1110.5 kg·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 accel-erating 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 potassi-um 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 compar-ison to formula fertilization, the contribution rate, agronomic use efficiency, partial fertilizer productivity and absorption ef-ficiency 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 de-composing 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.