作物产量和品质对钾镁肥增效配施的响应

由于农作物产量大幅度提高，氮、磷化肥施肥量的逐渐增加，化肥使用已明显不平衡，为此，适当调整氮、磷比例，配施一定量的钾镁肥势在必行。钾镁肥是一种以含硅镁钾钙为主，兼有多种营养元素的枸溶性长效缓释长效肥料，能协调土壤养分比例，增产效果比较显著。本文围绕高强度利用农田的肥料配施增效、提高肥料利用率这一核心，通过大田试验研究土壤微域钾镁肥不同配施对西北粮食作物、蔬菜以及果树产量的影响，分析了钾镁肥在西北不同作物的施用效果及最佳施肥量。大田试验结果发现，钾镁肥对粮食作物（小麦和玉米）有显著的增产作用，增施钾镁肥每亩25 kg、50 kg、75 kg后小麦增产幅度分别为9.8%、22.6%和13.1%；每亩增施钾镁肥75 kg和100 kg后玉米产量增产幅度分别为13.1%和19.2%。钾镁肥对黄瓜有极显著的增产作用，每亩增施钾镁肥100 kg、同当量钾的硫酸钾和硫酸镁混合肥、单质硫酸钾和单质硫酸镁均有增产效果，增产幅度分别为41.0%、23.2%、10.8%和6.5%。根据对黄瓜整个生育期的观察，施钾镁肥后，黄瓜叶色深绿、叶片大而厚且生育期延长，结瓜早且瓜直无畸形瓜。猕猴桃施用钾镁肥后，棵树叶片基本转绿，果实无黄化，每棵施钾镁肥2.0 kg可增产13.8%。本文试验结果为集约化栽培区钾镁肥配施推广应用提供依据。

Effectiveness of combined application for potassium-magnesium fertilizer on crops

Due to an intensive increase of crop yields, an application of nitrogen and phosphorus fertilizer is gradually growing, resulting in imbalance of fertilizer application. It urgently needs to adjust the proportion of nitrogen and phosphorus fertilizer application and call for the combined application of potassium-magnesium fertilizer. Magnesium ions are found in the center of chlorophyll molecules, and as chlorophyll is an essential component in the reaction of photosynthesis, which produces energy for growth, magnesium ions are therefore essential. Potassium is needed for chemical reactions of the plant cell and helping to transport other ions needed by the plant. It helps in the formation and movement of carbohydrates. Potassium and magnesium facilitate plant energy production by improving the production and regeneration of ATP, the biochemical battery molecule that stores and releases energy supply of plant. Focusing on the combined application of fertilizer in farmland for increase of crop yields and fertilizer use efficiency, we conducted a field experiment to study an effectiveness of combined application for potassium-magnesium fertilizer on different crops in Xi’an and analyzed an optimal application amount for different crops. The results showed that the combined application of potassium-magnesium fertilizer has significant effect on wheat, corn and cucumber. Crop yields of wheat increased by 13.54%, 22.56 % and 9.81% after application of 375kg ha-1, 750kg ha-1and 1125 kg ha-1 potassium-magnesium fertilizer, crop yields of corn increased by 5.9%, 11.56% and 16.09% after application of 750 kg ha-1 , 1125 kg ha-1and 1500 kg ha-1 potassium-magnesium fertilizer. Application of same quantity fertilizer from the different potassium-magnesium fertilizer varieties has significantly increased the yield of cucumber based on the same amount of N, P. Application of potassium-magnesium to cucumber has an significant increasing yield by 29.06 %. The yield of cucumber increased by 9.7％, 6.3％ and 18.85％ by application of only potassium sulfate of 437 kg ha-1, magnesium sulfate of 360 kg ha-1 and the combined application of potassium sulfate of 437 kg ha-1 with magnesium sulfate of 360 kg ha-1. The treatment with fertilizer of magnesium potassium sulfate provides higher yield and quality than that only with potassium sulfate. The yield of Kiwifruit increased by 13.81％ after application with potassium-magnesium of 2.0 kg per plant. The relative fruit quality an