Background This study evaluated the effect of Jatropha curcas seed oil against adult American cockroach, Periplaneta americana , a mechanical disease vector, using three bioassay methods to determine the repellent activity, contact and fumigant toxicity. This involved the use of J. curcas oil solution (diluted with acetone (20%)) and J. curcas pure oil. For repellency test, concentrations 0.30, 0.60 and 0.90% v/v were used for the oil solution while 1.0 and 2.0 ml concentrations were used for the pure oil. All test groups were exposed for 15 min. Contact toxicity test involved the use of 0.30, 0.60, 0.90, 1.20 and 1.50% v/v concentrations for the oil solution while 1 and 2 ml concentrations were used for the pure oil. Exposure period for all test groups was 24–120 h. For the fumigant test, 0.15% v/v and 0.5 ml concentrations were used for the oil solution and pure oil groups respectively; exposure period for the test groups was 24–120 h. All test and the control groups had ten cockroaches ( P. americana ) per group with four replicates. Results Repellency was higher in test groups treated with pure J. curcas oil than in groups treated with the oil solution with repellency of 70–100% and 60–100% respectively after 15 min exposure period. For the contact test, a higher mortality rate was observed with the oil solution than the pure oil. Mortality was lower for 1 ml of pure oil with 20% at 24 h and 40% at 120 h than 2 ml of pure oil with 30% mortality at 24 h and 50% mortality at 120 h. A 100% mortality was recorded in the highest concentration (1.50% v/v) at 120 h. Fumigation test with 0.15% v/v of oil solution resulted in 20% mortality at 120 h while fumigation test with 0.5 ml of J. curcas pure oil resulted in 60% mortality at 120 h. Conclusion J. curcas seed oil possesses repellent and insecticidal properties against P. americana . Thus, the menace caused by this mechanical disease vector could be reduced using J. curcas seed oil.

中文翻译：

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Jatropha curcas L. 种子油对美洲蟑螂 Periplaneta americana L. 的驱避和杀虫特性。

背景 本研究使用三种生物测定方法来确定驱虫活性、接触和熏蒸剂毒性，评估麻风树种子油对成年美洲蟑螂、美洲大蠊（一种机械病媒）的影响。这涉及使用麻疯树油溶液（用丙酮 (20%) 稀释）和麻疯树纯油。对于排斥性测试，油溶液使用浓度为 0.30、0.60 和 0.90% v/v，而纯油使用浓度为 1.0 和 2.0 ml。所有测试组均暴露 15 分钟。接触毒性试验涉及使用 0.30、0.60、0.90、1.20 和 1.50% v/v 浓度的油溶液，而 1 和 2 ml 浓度用于纯油。所有测试组的暴露时间为 24-120 小时。对于熏蒸剂测试，0.15% v/v 和 0。油溶液组和纯油组分别使用5ml的浓度；测试组的暴露时间为 24-120 小时。所有试验组和对照组每组有 10 只蟑螂 (P. americana)，重复四次。结果 在暴露 15 分钟后，用纯麻疯树油处理的测试组的驱避率高于用驱避率分别为 70-100% 和 60-100% 的油溶液处理的组。对于接触测试，观察到油溶液的死亡率高于纯油。1 ml 纯油的死亡率在 24 小时时为 20%，120 小时时为 40%，而 2 ml 纯油的 24 小时死亡率为 30%，120 小时时死亡率为 50%。在 120 小时的最高浓度 (1.50% v/v) 中记录到 100% 的死亡率。0. 熏蒸试验。15% v/v 的油溶液导致 120 小时的死亡率为 20%，而使用 0.5 毫升麻疯树纯油的熏蒸试验导致 120 小时的死亡率为 60%。结论麻疯树籽油对美洲野马具有驱避和杀虫作用。因此，使用麻疯树种子油可以减少由这种机械病媒引起的威胁。