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近几年来,在江苏各地场圃的铅笔柏病害发生比较普遍而严重,主要为害1～7年生的铅笔柏,尤其1～3年生的幼苗受害更重。根据笔者1986年6～10月调查,射阳县林科所二年生铅笔柏发病死亡率为40.9%;南京丁祥园艺场四年生铅笔柏发病死亡率为23.7%;吴县胥口乡五年生铅笔柏发病率为76.7%,其实,上述数字不是一种病害所致。铅笔柏的病害种类颇多,有些症状很相似,较难区别。现已发现有柏树疫病(即铅
In recent years, the diseases of Penaeus japonicus in field gardens in Jiangsu Province have been more common and serious, mainly affecting 1 to 7 years old pencil cypress, especially 1-3 years old. According to the author’s investigation from June to October 1986, the death rate of two-year-old pencil cedar in Sheyang Forestry Bureau was 40.9%; the death rate of four-year-old pencil cedar in Nanjing Dingxiang horticultural field was 23.7%; the five-year-old pencil cedar The incidence rate was 76.7%. In fact, the above figure is not a disease. Penaeus many diseases, some symptoms are similar, more difficult to distinguish. Has been found to cypress disease (ie lead