钾肥不同施用量对玉米产量和效益及钾素平衡的影响

研究了黑龙江省玉米主产区双城地区不同钾肥施用量条件下,玉米产量、养分吸收规律以及土壤—作物系统中钾素投入—产出平衡状况。结果表明:施钾可明显增加玉米植株各部分含钾量,对秸秆钾含量的提高尤其明显。在一定范围内施用钾肥可显著提高玉米籽粒产量,随着施钾量增加,籽粒产量没有进一步提高,从而使钾肥效益降低。施钾肥的K1、K2、K3、K4处理分别比K0产量增加1 190、1 460、1 070和729 kg.hm-2;各处理钾含量大小顺序为:籽粒K4K3K2K1K0;秸秆K4K3K1K2K0;各处理钾表观盈亏量均为负值,其中K1和K2处理钾的亏缺程度最大。双城地区钾的平衡系数均小于1。从产量、效益及平衡系数看,该地区钾肥用量以K2O 100 kg.hm-2为宜,可使土壤钾素趋于动态平衡,达到玉米的高产、优质和高效。

Effect of Potassium Fertilizer on Yield Benefit of Maize and Potassium Balance of Soil-Crop System

Maize yield and the nutrient＇s absorption characteristic of potassium input-output balance in soil-crop system were studied under the condition of different potassium application rates in the main maize production areas of Heilongjiang province.The results showed that K fertilizer could increase potassium content of different organs in plant distinctly,especially in straw.Application of K fertilizer could increase yield of grain but yield didn＇t increase with K fertilizer quantity＇s increasing and then K fertilizer＇s efficiency decreased.The average yields of the maize under the K1,K2,K3,K4 treatments were increased by 1 190,1 460,1 070 and 729 kg·hm-2compaerd with the K0 treatment;The order of the potassium content of the treatments was：grainK4K3K2K1K0;strawK4K3K1K2K0.The apparent budget of Potassinm was negative,the extent of K1 and K2 were the most.Potassium balance coefficient was less than 1.According to yield,benefit and balanced coefficient,the best application of K fertilizer was K2O 100 kg·hm-2,which would make the fertilizer application more reasonable to reach high-yield,high-quality and efficient maize.