油菜田草害不仅与油菜争光照、争肥水，使菜苗长势瘦弱，抗性降低，同时还影响油菜基部的通透性，增加了湿度，给病菌的滋生、蔓延创造了良好的环境条件。为了解不同草害发生程度对油菜菌核病的影响，１９９８年我们开展了不同杂草发生量与菌核病发生关系的研究。１　材料与方 Rape field grass pest not only competing with the rape of light, fight fertilizer, so that the seedlings growing thin, resistance to reduce the permeability of rapeseed base at the same time, increased humidity, to the breeding of bacteria, the spread created a good environmental conditions. In order to understand the impact of different degree of grass damage on rape Sclerotinia, in 1998 we conducted a study on the relationship between the occurrence of different weeds and sclerotinia. 1 material and side