在玻璃表面上短时接触硅藻土和多杀菌素对四纹豆象的致死效应和亚致死效应（英文）

四纹豆象Callosobruchus maculatus (F.)是伊朗豇豆种子上的主要贮藏害虫。控制这一害虫时， 用生物杀虫剂比用常规杀虫剂更为合适。本研究评价了室内条件下在玻璃表面上硅藻土和多杀菌素对四纹豆象成虫的致死效应和亚致死效应。结果表明： 硅藻土处理24 h和48 h后， 对四纹豆象成虫的LC50 值分别为 1.47和0.2 g/m²； 多杀菌素处理24 h和48 h后， 对四纹豆象成虫的LC50 值分别为102.9 和68.8 mg ai/L， 说明两种化合物都对四纹豆象成虫具有较高的急性毒性。通过检测生物学参数， 研究了LC₂₀浓度的硅藻土和多杀菌素对四纹豆象的亚致死效应。LC₂₀浓度的硅藻土和多杀菌素使四纹豆象成虫的繁殖力分别比对照降低了71.5%和17.2%， 卵孵化率降低了57.5%和27.8%， 成虫寿命缩短了74.7%和17.1%。接触LC₂₀浓度的硅藻土和多杀菌素使这一害虫的蛹期分别比对照延长了4.8%和2.3%。亚致死效应研究表明， 硅藻土和多杀菌素对四纹豆象的生命参数均产生了负面影响。总之， 致死效应和亚致死效应综合显示， 硅藻土在防治四纹豆象上具有较大的潜力。

Lethal and sublethal effects from short-term exposure of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) to diatomaceous earth and spinosad on glass surface

The cowpea weevil, Callosobruchus maculatus (F.) (Coleoptera: Bruchidae), is the main storage pest of cowpea seeds in Iran. Using biorational insecticides instead of conventional insecticides is an appropriate alternative for controlling this pest. In this study, the lethal and sublethal effects of diatomaceous earth and spinosad against C. maculatus adults on glass surface were evaluated under laboratory conditions. The results indicated that the LC₅₀ values at 24 and 48 h after treatment were 1.47 and 0.2 g/m² for diatomaceous earth and 102.9 and 68.8 mg ai/L for spinosad, respectively. Both compounds had high acute toxicity against cowpea weevil. Sublethal effects of LC₂₀ concentration of the diatomaceous earth and spinosad against C. maculatus adults were studied by detecting biological parameters. LC₂₀ concentration of diatomaceous earth and spinosad reduced the fecundity of the pest by 71.5% and 17.2%, the egg hatching rate by 57.5% and 27.8%, and adult longevity by 74.7% and 17.1%, respectively, compared to the control. Pupal period of the insect exposed to LC²⁰ concentration of diatomaceous earth and spinosad increased by 4.8% and 2.3%, respectively, compared to the control. The sublethal effect study showed that both diatomaceous earth and spinosad negatively affected life parameters of cowpea weevil. In general, combination of lethal and sublethal effects revealed that diatomaceous earth had high potential in controlling cowpea weevil.