桔大实蝇(Tetradacus citri Chen.)是柑桔的一种大害虫,又为检疫对象之一。它在四川分布很广,包括37个县市,以江津为害最严重。此外尚分布在湖北、湖南、陕西、云南、贵州、广西等省75个县市。柑桔果实每年遭受很大的损失。就四川江津而言,解放前据1949年材料,果实受害率达50％左右,受害严重地区几乎达 Tetradacus citri Chen. Is a large pest of citrus and one of quarantine objects. It is widely distributed in Sichuan, including 37 counties and cities, most severely damaged by Jiangjin. In addition, it is still distributed in 75 counties and cities such as Hubei, Hunan, Shaanxi, Yunnan, Guizhou and Guangxi. Citrus fruits suffer huge losses each year. As far as Sichuan Jiangjin is concerned, before the liberation, according to the materials of 1949, the damage rate of fruit was about 50%, and the area hardest hit was almost