Impact of cutting frequency on the productivity of Medicago sativa cv. Zhaodong

Cutting is the main harvesting way for alfalfa and the cutting frequency affects not only the hay yield and quality but also the overwintering rate. Medicago sativa cv. Zhaodong is the main variety in Harbin and it is important to determine its cutting frequency for the alfalfa production. In twoyear cutting experiment, the hay yield, crude protein yield and overwintering rate were measured. The data of different cutting treatments were comprehensively evaluated by the gray relevancy analysis method. The results indicated that the proper cutting frequency in Harbin was 2 times per year. The correlation analysis result indicated that the cutting frequency significantly negative correlated with the productivity.