Study on the Effects of Balanced Fertilization and Application of Potassium Fertilizer on Sweet Potato

The yield of sweet potato reached 28 666.67 kg/hm2 using the high-yielding cultural and balanced fertilization techniques in semi-arid area in West He'nan.The yield increased 7.07-26.26 kg by 1 kg K2O.The results showed that the yield of Shangshu 19 increased 195 133.34-9 233.34 kg/hm2 and the increasing rate were 26.42%-47.51% based on 7.5 t/hm2 organic fertilizer and 375 kg/hm2 potassium fertilizer.Compared with the treatment of-K,the other treatments could increase the number of sweet potato per plant,the branch number and fresh sweet potato weight per plant by 15.21%,36.80% and 29.86%,respectively,and decrease the length of longest vine by 7.45%.The yield increase based mainly on the increasing of fresh sweet potato weight per plant,then on the increasing of fresh sweet potato weight per plant.On the basis of the application of proper quantity of organic fertilizer and nitrogen and phosphorus fertilizer,the quantity of K2O for high yield and high efficient was 375 kg/hm2.