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桑炭疽病在浙江省杭州市一带于五十年代即有发现,那时主要为害桑苗,尤其是实生苗或一些早生桑的较老化的叶片,故对桑叶生产影响不大。到七十年代,此病的发生为害加剧。一些湖桑系统的桑树嫩叶也被害。根据1980年9月的调查,我校农场桑树的所有品种,全部不同轻重程度地被害,受害最重的形如火烧,严重影响蚕桑生产。为此,我们对以下几个问题进行了调查研究,现将初步结果整理如下。
Sang anthracnose found in the fifties of the 1950s in Hangzhou, Zhejiang Province, was mainly harmed by saplings, especially older plants or some older mulberry leaves, so it had little effect on the production of mulberry leaves. By the seventies, the disease had worsened. Some mulberry leaves of young mulberry trees are also killed. According to a survey conducted in September 1980, all the varieties of mulberry trees on our school farms were all severely damaged to the greatest extent, with the heaviest victims being severely affected by fire and seriously affecting the production of sericulture. To this end, we conducted a survey on the following issues, the preliminary results are now organized as follows.