Effect of Potassium Fertilizer Application on the Yield,Quality of Winter Wheat and Soil Available K Balance in Sandy Chao Soil

Field plot experiment was used to study the effect of potassium fertilizer application on the yield,quality of winter wheat and soil K balance in the sandy Chao soil in Henan province,the result showed that: when total potassium fertilizer was basically applied,the optimal yield and profit increment was obtained at potassium fertilizer rate of 150 kg·ha-1,as the potassium fertilizer rate increased,the content of grain protein and amylopectin starch showed ascendant trend but the ratio of amylose starch content /amylopectin starch content showed descendant trend;the soil available K content and plant K accumulation increased as the potassium fertilizer rate increased,to keep the soil available K balance,the potassium fertilizer rate must be above 150 kg·ha-1;Under condition of the same rate of potassium fertilizer,the regime with ratio of basal : dressing of 5∶5 showed better than that with total fertilizer as dressing on yield,profit and potassium fertilizer recovery;the seed protein content,the ratio of amylose starch content /amylopectin starch content at regime with ratio of basal:dressing of 5:5 showed better than that with total fertilizer as dressing,but amylopectin show adverse trend between those twe treatments.Considering of higher yield,profit,fertilizer recovery rate and soil K balance as a whole,the treatment with 150 kg·ha-1 of K2O application in two times was optimal with total increment of 1 225.23 kg·ha-1 of yield and 578.7yuan·ha-1 of profit increment,and with 8.17kg yield per kg K2O,with potassium fertilizer recovery rate of 53.4%,and with the soil available K balance.The soil available K level and plant K accumulation enhanced with the increase of potassium fertilizer rate.