Zheng X-L, Huang Z-Y, Li J, Yang Z-D, Yang X-H, Lu W
College of Agriculture, Guangxi Univ, Nanning, China.
College of Forestry, Guangxi Univ, Nanning, China.
Neotrop Entomol. 2018 Feb;47(1):19-25. doi: 10.1007/s13744-017-0502-6. Epub 2017 Mar 14.
Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae) is an invasive pest in Eucalyptus plantations around the world. The successful colonization of L. invasa is possibly related to its reproductive biology. The objective of this study was to examine the reproductive biology of L. invasa. In Guangxi Province, the sex ratio (proportion of female, 0.99) of L. invasa was female-dominant throughout the year based on natural and artificial infestation. This result was similar to the ratios observed for other geographic populations in China, including those in Fujian (0.99), Guangdong (0.98), Hainan (0.95), Jiangxi (0.96), and Sichuan (0.99). The offspring sex ratio favored females. A large number of females emerged from the galls produced by females, with few males found. Galls on the petioles and midribs of Eucalyptus plants could be caused by newly emerged females with mature eggs. The lengths of the ovariole, spermatheca, common oviduct, and reproductive glands did not differ among L. invasa females, but their lateral oviducts showed differences from 0 to 42 h after emergence, indicating that this insect is proovigenic. These results could explain why L. invasa populations can rapidly increase in invaded areas.
桉树枝瘿姬小蜂（Leptocybe invasa Fisher & La Salle，膜翅目：姬小蜂科）是一种在世界各地桉树人工林中的入侵害虫。桉树枝瘿姬小蜂的成功定殖可能与其生殖生物学有关。本研究的目的是研究桉树枝瘿姬小蜂的生殖生物学。在广西，基于自然和人工侵染，桉树枝瘿姬小蜂的性别比（雌性比例，0.99）全年以雌性为主。这一结果与在中国其他地理种群中观察到的比例相似，包括福建（0.99）、广东（0.98）、海南（0.95）、江西（0.96）和四川（0.99）。后代性别比有利于雌性。大量雌性从雌虫产生的虫瘿中羽化，雄虫很少。桉树叶柄和中脉上的虫瘿可能由具有成熟卵的新羽化雌虫造成。桉树枝瘿姬小蜂雌虫的卵巢管、受精囊、公共输卵管和生殖腺长度没有差异，但它们的侧输卵管在羽化后0至42小时显示出差异，表明这种昆虫是先行生殖的。这些结果可以解释为什么桉树枝瘿姬小蜂种群在入侵地区能够迅速增加。
