Abstract: Grading scale for the ovarian development of rice water weevil (RWW), Lissorhoptrus oryzophilus Kuschel, was presented in the light of the practices for pest forecast in China and the operationability in grass roots extension station. According to the morphological changes in ovarian development, their anatomical criteria were classified into six grades, i.e. 0, no oocyte; Ⅰ, previtellogenic; Ⅱ, gravid (vitellogenic to chorionated eggs); Ⅲ, ovipositing (a number of chorionated eggs are stored in the egg calyxes); Ⅳ, late egg laying (the early and middle degeneration); Ⅴ, postoviposition senescence (the late degeneration). These criteria were applied to characterize the field population of RWW and to appraise the suppression effect of some insecticides (say Imidacloprid) that cause the ovarian development retardation and egg laying dysfunction.

Key words: grading criteria, Lissorhoptrus oryzophilus, ovarian development, population characteristics

摘要： 根据我国病虫测报工作中害虫卵巢分级的实践及基层站点的可操作性，提出一套稻水象甲的卵巢发育程度的分级标准，即分为发育前期(0级)、卵黄沉积前期(Ⅰ级)、卵黄沉积期(Ⅱ级)、产卵盛期(Ⅲ级)、产卵末期(Ⅳ级)和产后衰老期(Ⅴ级)六个级别。据此结合飞行肌和脂肪体的发育程度，可作为常规监测中确定稻水象甲种群性质的指标。

关键词: 稻水象甲, 卵巢发育, 分级标准, 种群性质