北京市苜蓿种植业发展迅速,目前种植面积已达1.733万hm2。但近年来病害渐趋严重,已成为苜蓿生产中的突出问题。为了解其主要病害在不同品种间的抗病性差异,在2001年对北京市苜蓿品种圃和苜蓿生产区病害发生程度调查的基础上,2002年8月又进行了调查。1病害发生情况经调查,目前北 The alfalfa cultivation industry in Beijing is developing rapidly. At present, the planting area has reached 17.33 thousand hm2. However, the disease has become increasingly serious in recent years and it has become a prominent problem in alfalfa production. In order to understand the difference of disease resistance between different varieties in its main diseases, a survey was conducted in August 2002 on the basis of a survey of the degree of occurrence of diseases in alfalfa nurseries and alfalfa production areas in Beijing. 1 disease after investigation, the current North