大猿叶虫滞育进程中成虫内生殖系统的形态特征

Morphology of internal reproductive system associated with diapause process in the cabbage beetle,Colaphellus bowringi

大猿叶虫Colaphellus bowringi Baly是十字花科蔬菜的一种重要害虫,以成虫在土壤中滞育越冬和越夏。本研究通过解剖大猿叶虫非滞育成虫,观察描述了雌雄成虫内生殖系统的结构特点,并绘制了雌雄成虫内生殖系统模式图。对滞育初期、滞育期间、滞育解除后未取食和滞育解除后取食成虫解剖显示,滞育初期,雌雄成虫内生殖系统几乎与羽化初期成虫一致。滞育期间雄成虫的附腺和射精管亦不发达,滞育解除后未取食雄成虫的附腺膨大且粗于输精管,射精管略膨大,取食雄成虫的射精管呈不透明淡桔黄色。滞育期间雌成虫的卵巢小,略大于滞育初期卵巢,少数卵巢小管的基部可见具卵黄原沉淀的卵粒。滞育解除后未供食雌成虫卵巢明显膨大可见大量成形卵粒,部分卵粒可见卵黄原沉淀;取食雌成虫的卵巢膨大,可见大量成熟卵粒,侧输卵管和总输卵管中可见待产的卵。作者认为,大猿叶虫成虫在滞育期间能够缓慢发育,部分滞育前积累的代谢物质被用于滞育后发育,但只有经过取食,成虫才能正常交配和产卵。

The cabbage beetle Colaphellus bowringi Baly,a pest of cruciferous vegetables,aestivates and hibernates as an adult in soil.Adults of this beetle were dissected and their internal reproductive systems described and illustrated.The internal reproductive system of newly diapausing adults is poorly developed and similar to that of newly emerged adults.In diapausing males,accessory glands and the ejaculatory duct are also poorly developed.In non-feeding post-diapause males,the accessory glands are swollen and obviously wider than the vas deferens,and the ejaculatory duct is obviously enlarged,whereas in feeding,post-diapause males the ejaculatory duct is obviously enlarged and light opaque yellowish-orange in color.In diapausing females,the ovarioles are small in size but slightly larger than those of newly diapausing females and some basal oocytes have faint yolk uptake.In non-feeding,post-diapause females,the ovarioles are developed,large and many basal oocytes have visible yolk uptake.In feeding,post-diapause females,the ovarioles are well developed,large and numerous chorionated eggs can be found at the base of each ovariole,lateral oviducts and the common oviduct.These results suggest that although reproductive development can continue in diapausing adults,and that a portion of the metabolites accumulated during the pre-diapause period can be used in post-diapause development,feeding is necessary for post-diapause mating and oviposition.