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近年来,在汕头地区有一种引起柑桔落叶的叶斑病——脂斑病。它使柑桔发生大量落叶,削弱树势,影响产量,尤以椪柑和蕉柑受害为重。目前该病有严重发展和漫延的趋势。叶片受害初期,在对光的情况下,能见到小黄点,继而在叶片出现针头大、圆形、褐色、油渍状略隆起病斑,后期许多小点并合或扩大,成不规则的晴褐色或黑色具釉光隆起的大病斑或联合成片。病斑生于叶背,叶面较少。既为害春梢,也为害秋梢。1952年日本人确定该病病源是有性世代为Mycospharella horiihara的尾孢(cercospora)型
In recent years, there has been a leaf spot disease caused by orange deciduous leaves in Shantou. It makes a lot of citrus leaves decay, weaken the tree vigor, affecting the yield, especially citrus and banana damage. At present, the disease has a serious tendency of development and spread. In the early stage of victimization of leaves, small yellow dots can be seen in the case of light, followed by slight, rounded, brown, and greasy needle-like lesions in the leaves, and many small dots later merge or expand into irregular Bright brown or black enamel light bulging large lesions or joint into pieces. Lesions were born in leaves back, leaves less. Both harmful spring shoots, but also for the autumn tip. Japanese in 1952 to determine the source of the disease is sexual generation Mycospharella horiihara cercospora type