控释钾肥对玉米产量、钾肥利用率和土壤速效钾的影响

通过玉米—小麦轮作条件下连续2年的大田定位试验,以钾空白(CK)、普通氯化钾常量(K1)、普通氯化钾高量(K2)为对照处理,研究通过控释氯化钾常量(CRK1)、控释氯化钾高量(CRK2)、氯化钾与控释氯化钾等比掺混常量(BBF1)、氯化钾与控释氯化钾等比掺混高量(BBF2)处理对玉米产量、钾肥利用率和土壤速效钾的影响。结果表明:(1)BBF2玉米-小麦季产量分别为11 697.8kg/hm2和11 921.1kg/hm2,增产和增收效果最好,较K1分别显著增产13.3%和15.7%,较K1分别显著增收16.6%和19.6%;(2)BBF2钾肥农学利用率较K1分别显著提高了49.0%和41.9%,生理利用率较K1分别显著提高了17.6%和34.8%;BBF1钾肥表观利用率最高,玉米—小麦分别为23.73%和35.22%;(3)施用钾肥显著提高了玉米的株高和茎粗;BBF2提高了玉米吐絮后期至成熟期的株高;CRK1、CRK2、BBF1、BBF2均提高了玉米吐絮后期叶片SPAD值。本试验条件下,控释氯化钾与普通氯化钾掺混施用可满足玉米整个生育期的钾素需求,提高玉米产量和钾肥利用率,BBF2处理为玉米最佳钾肥施用方案。

s of Controlled-release Potassium Fertilizers on the Yield of Maize, Potassium Use Efficiency and Soil Available Potassium

Effects of the usual controlled-release potassium chloride (CRK1), the high controlled-release potassium chloride (CRK2), the usual mixed potassium chloride with controlled-release potassium chloride (BBF1) and the high mixed potassium chloride with controlled-release potassium chloride (BBF2) on maize yield, potassium use efficiency, and soil available potassium were investigated in a 2-year field experiment using maize-wheat rotation system, and the none potassium (CK), the usual potassium chloride (K1) and the high potassium chloride (K2) were set up as controls. To provide the basis for application of controlled release potassium chloride, studied the synchronous nutrition relationships of between controlled-release fertilizers with maize. The results showed that: (1) The yield of maize under BBF2 treatment in 2014 and 2015 were 11 697.8 kg/hm2 and 11 921.1 kg/hm2, respectively. Compared with K1 treatment in the 2014 and 2015, the yield increased by 13.3% and 15.7%, respectively and the incomes increased 16.6% and 19.6%, respectively. (2) The agronomic potassium use efficiency under BBF2 treatment was greater significantly by 49.0% and 41.9% over those of the K1 treatment in 2014 and 2015, respectively. The physiological potassium use efficiency under BBF2 treatment was greater significantly by 17.6% and 34.8% over those of the K1 treatment in 2014 and 2015, respectively. The highest apparent potassium use efficiency occurred in BBF1 treatments, which were 23.73% and 35.22% in 2014 and 2015, respectively. (3) Plant height and stem diameter were significantly increased with potassium fertilizer application. Maize plant height increased under BBF2 treatment from the later tasseling stage to the mature stage. Both CRK and BBF treatments increased significantly the leaf SPAD values of the late tasseling stage, and significantly improved the absorption of potassium and enhanced grain filling properties. The results indict that the application of the mixed potassium chloride with controlled-release potassium chloride can meet the maize nutrition requirement of different growth period, and improved maize yield and potassium use efficiency, among which, BBF2 treatment is the optimal fertilization scheme.