Characteristic and Measures for High Yield Cultivation of Sweet Potato Cultivar Guangshu 87 with Good Quality

With its desirable properties of high yield,wide adaptability, high dry matter and starch contents, as well as good cooking and eating quality,Guangshu 87 was certified and released for commercial production in Fujian in 2009. It has been since then widely used in commercial production. Based on the yield factors (i.e., planting density and fertilization rate), cultivation of Guangshu 87 was studied and optimized by using the rotational regression analysis. The results showed that the cultivation measures affecting the yield included and ranked in the order of planting density (X1) k fertilization (X4) N fertilization(X2) P fertilization(X3). Optimization by computer showed that the model that gave the highest yield of 47 864.03 kg.hm-2 could be achieved by planting at a density ranging from 55 100-57 300 plantshm-2 and applying urea at 264.34-283.58 kghm-2, calcium superphosphate at 423.45-476.55 kghm-2 and potassium sulfate at 414.15-458.25 kghm-2.