施钾对春玉米产量、养分吸收及分配的影响

通过连续两年田间试验,研究吉林省中部玉米主产区施钾对春玉米产量、养分吸收、转运、分配及钾肥利用率的影响。结果表明,施用钾肥可显著提高春玉米产量,在一定施钾范围内,春玉米产量随施钾量的增加而增加,当施钾量超过90 kg/hm2后产量不再增加,根据玉米产量(y)和施钾量(x)拟合,得出最佳施钾量为82.9~86.6 kg/hm2。施钾肥可提高干物质最大积累速率和积累总量、养分最大吸收速率和吸收总量,提前干物质最大积累速率和养分最大吸收速率出现的时间。施钾可提高春玉米氮、磷、钾养分向子粒的转运量及转运率,施钾量30~90 kg/hm2范围内抽雄期养分积累量与子粒转运量和转运率呈正比,当施钾量超过90 kg/hm2后,氮、磷、钾养分转运出现负效应。钾素农学利用率和偏生产力随着施钾量的增加而下降,钾肥当季回收率以施钾量90 kg/hm2处理最高。在吉林省中部玉米主产区,适宜施钾量为82.9~86.6 kg/hm2。

Effects of Potassium Fertilizer Application on Yield, Nutrient Absorption and Distribution of Spring Maize

Field experiments were conducted to study the effects of potassium fertilizer application on yield, nutrient absorption, transformation and potassium utilization efficiency in main maize production areas in central Jilin province. The results showed that potassium fertilizer application improved the yield of spring maize significantly. The yield of spring maize was increased in a certain range of potassium application rates, but it was not increased anymore when potassium application rates exceeded 90 kg/ha. Simulated by linear-plateau models, the optimum potassium application rate was 82.9-86.6 kg/ha. According to maize yield(y) and potassium application rates(x) fitting, potassium fertilizer application increased the maximum rates and the total amounts of dry matter accumulation and nutrients absorption, also occurred the time early of the maximum rates of dry matter accumulation and nutrients absorption. Potassium fertilizer application could enhance the translocation amounts and rates from N, P, and K nutrition to grain in spring maize. The amounts of nutrient accumulation at tasseling stage was proportional to the amounts and rates of the translocation to grain at the range of 30-90 kg/ha(K₂O), but it could cause negative effect for N, P and K nutrients translocation, when potassium application rates exceeded 90 kg/ha. Agronomic efficiency and partial factor productivity of potassium were reduced by increasing potassium application rates, and the treatment of 90 kg/ha(K₂O) got the highest value of potassium recovery efficiency. The recommended optimum potassium dosages for areas was 82.9-86.6 kg/ha in main maize production areas in central Jilin province.