上海地区棉铃炭疽病的流行规律

对棉铃炭疽病在上海地区的发生和流行作了系统观察,结果表明此病始发于8月下旬,主要发生在9月份,有些年份可延长至10月上旬。棉铃龄期与病害发生有关,40～60天的棉铃发病比率相对较高,病害主要发生在中下部棉铃上。影响病害发生的气候因素分析表明,降雨量是影响炭疽病发生的主要因素,在病害流行阶段,雨量多的年份病害发生往往严重。

EPIDEMICS OF COTTON BOLL ANTHRACNOSE IN SHANGHAI

Incidence and epidemics of cotton boll anthracnose (Colletotrichum gossypii Smith) have been systematicaly investigated in Shanghai. The results showed that the incidence of boll rot appeared in the late of August, mainly in September, and less occurred in the primary of October, the boll rot incidence was related to the age of cotton boll, and the ration of the age offorty tosixty days boll rot was higher than that of others. Moreover, the anthracnosepathogen mainly infested cotton bolls at the mcdialand lower situs of plants. The rainfall was the major factor which affected the epidemics of cotton boll anthracnose. The more the rain fall, the severer theboll rots are.