钾肥用量对油菜产量及钾素利用效率的影响

通过11个大田试验研究了钾肥用量对油菜产量、养分含量、养分累积量及钾肥利用效率的影响。结果表明,施钾（K2O）60、120和180kg/hm2与不施钾相比平均籽粒产量分别增加16.9%、21.6%和19.8%,籽粒含钾量增加2.7%、9.0%和7.8%,植株地上部钾素总累积量提高42.9%、63.0%和82.2%。说明施钾能提高油菜籽产量、提高油菜对钾素吸收和累积。油菜钾肥农学利用率、偏生产力、表观利用率和生理利用率均随钾肥用量的增加而显著下降,100kg籽粒需钾量随钾肥用量的增加而增加。综合结果表明,湖北省油菜钾肥高产高效生产的推荐使用范围为60～120kg K2O/hm2。

Effect of potassium application rate on yield and fertilizer-potassium utilization efficiency in rapeseed

Eleven field experiments were carried out to study the effects of potassium（K） application rate on rapeseed yield,nutrient concentration,nutrient accumulation and fertilizer-K use efficiency in Hubei province during 2007-2008.Compared to no K treatment,the average yield of the treatment with K2O rates 60,120 and 180kg/hm2 increased by 16.9%,21.6% and 19.8%,with average K content increased by 2.7%,9.0% and 7.8%,total K uptake by the aboveground parts of rapeseed average increased by 42.9%,63.0% and 82.2%,respectively.The results illustrated that K application increased the yield,K concentration and accumulation of rapeseed significantly.With K application rate increase,K agronomic use efficiency（AUE）,partial factor productivity（PFP）,apparent recovery efficiency（ARE） and physiological use efficiency（PUE） of rapeseed were decreased significantly.However,K requirement for 100kg seeds of rapeseed was increased with K application rate increase.Based on rapeseed yield and K use efficiency,the optimum fertilizer application was 60~120kg/hm2 of K2O in Hubei province.