中文摘要：

利用大田试验研究了江汉平原生态区水稻一油菜轮作制中钾肥的施用对水稻和油菜的产量及农田钾素平衡的影响。结果表明，施钾量为187．5kg/hm2时，水稻和油菜产量均达到最高，与不施钾相比，水稻增产3007kg/hm2，增产率为45.4％；油菜增产757kg／hm2,增产率为40．4％。增施氮、钾肥增加作物养分吸收量，钾肥用量187．5kg/hm2时，钾吸收量为553．3kg/hm2，氮吸收量为279．9kg/hm2。水稻-油菜轮作中所有处理钾素养分平衡均出现亏缺，但增施钾肥缓解了土壤钾素亏缺程度；所有处理氮素均出现不同程度的盈余。

英文摘要：

Effect of K application on the yield and potash balance of rice-rapeseed rotation system in Jianghan plain were studied. The results showed that rice and rapeseed yield reached the highest with 187.5 kg K20/hm2 and increased rice yield 3 007 kg/hm2, the rate of growth was 45.4%, increased rapeseed yield 757 kg/hm2, the rate of growth was 40.4%. N and K increased nutrient accumulative cotent of crops. Crops absorbed K 553.3 kg/hm2,N 279.9 kg/hm2 with 187.5 kg K20/hmz. In rice-rapeseed rotation system, potassium showed deficit in all treatment ,but the deficit potash was decreased when K application was increased, while nitrogen showed surplus.