柑桔大实蝇产卵器的结构及形态观察

The observation of structural and morphological characteristics of the ovipositor of Chinese citrus fly,Bactrocera minax

柑桔大实蝇Bactrocera minax(Enderlein)是柑桔果树上的重要害虫,近年来危害日趋严重,对我国柑桔生产造成了严重影响。本文在室内及野外观察了柑桔大实蝇雌虫产卵器的结构及外部形态特征。结果表明:产卵器分为产卵器基节、翻转膜、产卵管三部分,其长度依次为:4.63±0.38 mm、5.24±0.28 mm、4.39±0.32 mm,产卵器拉伸全长为14.24±0.27 mm。产卵器有3种状态:正常状态、产卵前准备状态、产卵状态。产卵前准备状态表现为产卵器完全伸长,可弯曲、反复旋转并回折成γ形。在雌虫产卵状态时,产卵器基节留在果实外,产卵管刺穿透果皮后在果皮下产卵。

The Chinese citrus fly, Bactrocera minax （Enderlein）, is one of the most important pests in Citrus plants, which caused serious damage in recent years in China. The ovipositor of female adult was observed, photographed and measured under stereomicroscope. Moreover, field observation was conducted to figure out the characteristics of its ovipositor in different states. The results showed the ovipositor of female fly could be divided into three parts, i. e. , oviscape, eversible sheath and aculeus, with the length of 4.63 ± 0. 38 mm, 5.24 ± 0.28 mm and 4.39 ± 0. 32 mm respectively. After totally stretched, the ovipositor can extend up to 14.24 ± 0.27 mm. The ovipositor could occur in three states： normal state, pre-spawning state and spawning state. In pre-spawning state： the ovipositor is stretched in several forms such as curved like ＇U＇, rotated repeatedly or circled in a shape of y＇ During the spawning stage, the base section of ovipositor is always left outside the fruit, with the spawning needle pierced into the fruit. The peel is penetrated by the spawning needle controlling where the eggs would be ovulated.