随着畜牧养殖业的快速发展,尤其是奶牛养殖的迅速崛起,对牧草的需求越来越突出。紫花苜蓿种植应运快速发展起来,面积成倍增长。但由于紫花苜蓿生长过程中病虫害的发生及不恰当的防治,往往引起叶片 With the rapid development of livestock husbandry and aquaculture, especially the rapid rise of dairy farming, the demand for forage grass is becoming more and more prominent. Medicago sativa cultivation should be rapid development, area doubled. However, due to the occurrence of pests and diseases and the improper prevention and control during the growth of alfalfa, it often causes leaves