钾肥施用方式对直播和移栽水稻产量和钾肥利用效率的影响

采用田间试验研究了施钾量和基追比对直播和移栽水稻产量和钾肥利用效率的影响,以明确直播水稻和移栽水稻适宜的钾肥施用方式。结果表明,水稻施钾增产效果显著,当钾肥一次性基施时,钾肥施用量为270kg/hm ²的增产效果好于施135kg/hm ²,且钾元素积累量最高,但其钾元素利用率最低。当钾肥用量为135kg/hm ²时,直播水稻钾肥一次性基施与分次施用效果无显著差异,而移栽水稻钾肥分为基肥和穗肥两次施用与一次性基施相比增产效果显著。直播水稻施钾是通过获得较高的穗数以提高产量,移栽水稻施钾则是通过增加每穗颖花数和提高千粒重而达到高产。直播水稻钾肥一次性基施增加的纯收益、钾元素积累量和钾元素表观利用率略高于钾肥分次施用,但差异不显著;而移栽水稻则相反,钾肥分次施用的纯收益较钾肥一次性基施增加1 833元/hm ²,钾肥表观利用率显著高于钾肥一次性基施。研究表明施钾方式对直播水稻和移栽水稻产量提高及产量构成因子的影响存在差异,水稻生产应根据目标产量施足钾肥,建议直播水稻采用钾肥基施,而移栽水稻采用基肥和穗肥并重的运筹方式。

Effects of Potassium Fertilizer Application Method on Yield And Potassium Apparent Efficiency of Direct-Sowing Rice and Transplanting Rice

The effects of potassium (K) application rate and method on yield and K apparent efficiency of direct-sowing rice (DR) and transplanting rice (TR) were studied with the field experiment. The aim is to ascertained the appropriate K application method,The results showed that the K fertilizer application could obviously increase grain yields. Grain yield would be improved significantly when applying 270kg K₂O/hm ² as compared with 135kg K₂O/hm ². The K accumulation was highest, but the K apparent efficiency was lowest.When application rate was 135kg K₂O /hm ², there was no significant difference between basal application and fractional application on DR. In case of TR, the grain yield and net profit increment of fractional application (basal fertilizer and panicle fertilizer) were significant higher than basal application treatment. DT achieved high yield by a higher number of panicle with K application, while TR achieved high yield by a higher numbers of spikelet numbers per panicle and higher 1000-seed weight. The net profit, K accumulation and K apparent efficiency of basic application treatment were higher than fractional application on DT, but it had not significant difference. The TR was opposite. Compared with basic application treatment, the net profit increment of fractional application was 1 833 yuan/hm ². The apparent efficiency of fractional application treatment was significant higher than basic application treatment. The results indicated that K fertilization methods affected grain yield and yield component factors differently for the TR and DR. For the rice production, applying sufficient K fertilizer was needed to achieve the yield target. And we suggest basal K fertilization on DR and fractional applications on TR as the sound K fertilization managements.