Fruit flies are important insect pests of horticultural crops. Pesticides used to control them which cause environmental and health hazards; therefore, other alternative sustainable management measures are required. Successful implementation of an integrated pest management program, using biological control agents, needs synchronization of parasitoids with hosts selection and exposure time. The present study was conducted to assess the biological activity of the parasitoid species, Dirhinus giffardii (Silvestri) (Hymenoptera: Chalcididae), against the melon fruit fly, Zeugodacus cucurbitae (Coquillett), and the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), at different exposure durations (24, 48, and 72 h). The experiments were conducted under standard laboratory conditions. Significant differences in the parasitism rate of D. giffardii were observed for both species at different exposure durations. The maximum parasitism rate of D. giffardii (52.60 ± 2.84%) and (42.73 ± 2.74%) was observed at 48-h exposure period for Z. cucurbitae and B. dorsalis, respectively. Also, a comparison between both species showed a difference in parasitism rate at 24 and 48 h and a positive correlation between percent parasitism and exposure duration. Adult emergence of D. giffardii showed a maximum emergence rate from pupae of Z. cucurbitae (63.55 ± 4.02%) and B. dorsalis (51.61 ± 2.33%) at 10 days interval, respectively. However, the daily emergence of the parasitoid was not correlated to exposure duration in both species. The results of the present study may serve in the mass rearing of D. giffardii. The biological activity of D. giffardii was maximum at 48 h of exposure for both fruit fly species, and this important information may improve the mass rearing technology of D. giffardii.

中文翻译：

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寄生率的潜在Dirhinus giffardii（西尔维斯特）：在果蝇物种蛹（膜翅目Chalcididae），Zeugodacus cucurbitae（Coquillett）和桔小实蝇（实蝇）（双翅目：实蝇科），在变化的曝光持续时间

果蝇是园艺作物的重要害虫。用于控制农药的农药，造成环境和健康危害；因此，还需要其他替代性可持续管理措施。使用生物防治剂成功实施有害生物综合治理计划，需要将寄生虫与寄主选择和暴露时间同步。进行本研究是为了评估拟寄生物物种Dirhinus giffardii（Silvestri）（膜翅目：lc科）对瓜类实蝇Zeugodacus cucurbitae（Coquillett）和东方实蝇Bactrocera dorsalis（Hendel）的生物活性（ Diptera：Tephritidae），在不同的暴露时间（24、48和72 h）。实验在标准实验室条件下进行。在不同的暴露时间下，两种物种的吉非木蝇寄生率均存在显着差异。葫芦科和背果双歧杆菌在暴露48 h时观察到的D. giffardii的最大寄生率（52.60±2.84％）和（42.73±2.74％）。同样，两种物种之间的比较显示，寄生率在24和48 h有所不同，寄生率与暴露时间之间呈正相关。在10天的间隔内，葫芦丝D的成虫出现率最高，分别为葫芦Z（63.55±4.02％）和背侧芽孢杆菌（51.61±2.33％）。但是，在这两个物种中，每天寄生的寄生虫数量均与暴露时间无关。本研究的结果可用于吉氏疟原虫的大规模饲养。D的生物活性。