Insect pests of stored products such as the rice weevil, can be controlled in bulk and packaged grains by ionizing radiation (γ-radiation or X-ray radiation) and plant essential oils, used in combination or alone, as an alternative to standard chemical fumigantion. Irradiation source and dose rate may be factors influencing the efficacy of plant essential oils. We evaluated the effects of γ-radiation at three dose rates (10.445, 4.558, and 0.085 kGy/h) and X-ray irradiation at two dose rates (0.76 and 0.19 kGy/h) in combination with Eucalyptus () or Tea tree ( essential oil (EO) on the short-term mortality of . Adult weevils on rice in sealed Petri dishes were fumigated with 10 μL EO applied to a sponge then irradiated with a dose of 100, 250, 500, or 750 Gy. The combined treatment of Eucalyptus or Tea tree EOs with γ-irradiation or X-ray irradiation increased the mortality by 3–6 times as compared to irradiation treatment alone. The LD (predicted dose killing 90% of individuals) values for Eucalyptus EO plus γ-irradiation treated samples were 250.6, 252.8, and 522.4 Gy at dose rates of 10.445, 4.558, and 0.085 kGy/h, respectively, whereas the LD values for Tea tree EO plus γ-irradiation were similar (250.1, 255.07, and 574.3 Gy) when treated at dose rate of 10.445, 4.558, and 0.085 kGy/h dose rates, respectively. The lowest dose rate of γ-irradiation had the lowest efficacy in the combined treatment for both EOs. For the combined treatment of Eucalyptus or Tea tree EO with X-ray irradiation, LD values were 746.02 and 737.1 Gy with Eucalyptus EO and 632.03 and 615.5 Gy with Tea tree EO, at dose rates of 0.76 and 0.19 kGy/h, respectively. Overall, combined treatment LD values were significantly higher (less effective treatment) for X-ray than for γ-irradiation. Unlike γ-irradiation, the dose rate of X-ray irradiation did not affect efficacy in the combined treatments. Gamma or X-ray irradiation and plant EOs such as Eucalyptus or Tea tree EOs applied alone or in combination, are effective insecticidal treatments. The synergistic effects of irradiation and EOs may be source and dose rate dependent. Our results showed that synergistic effects with EOs against in rice was more effective (lower LD values) using higher dose rates of high energy γ-irradiation than at lower dose rates with either high energy γ-irradiation or low energy X-ray irradiation.

中文翻译：

---

使用精油和不同剂量率的伽马射线和 X 射线电离辐射联合处理对稻象甲的放射增敏作用


可以通过电离辐射（γ 辐射或 X 射线辐射）和植物精油联合或单独使用来控制散装和包装谷物中的稻象甲虫等害虫，作为标准化学熏蒸的替代方法。辐照源和剂量率可能是影响植物精油功效的因素。我们评估了三种剂量率（10.445、4.558 和 0.085 kGy/h）的 γ 射线照射以及两种剂量率（0.76 和 0.19 kGy/h）的 X 射线照射与桉树 () 或茶树 (将 10 µL EO 涂抹在海绵上，然后用 100、250、500 或 750 Gy 的剂量进行联合处理，对密封培养皿中稻米上的成虫象鼻虫的短期死亡率进行了熏蒸。与单独辐照处理相比，桉树或茶树 EO 经 γ 射线照射或 X 射线照射使死亡率增加 3-6 倍。剂量率分别为 10.445、4.558 和 0.085 kGy/h 时，样品的 LD 值分别为 250.6、252.8 和 522.4 Gy，而经处理后，茶树 EO 加 γ 辐射的 LD 值相似（250.1、255.07 和 574.3 Gy）剂量率分别为 10.445、4.558 和 0.085 kGy/h γ 辐射的最低剂量率在两种 EO 联合治疗中的疗效最低。对于桉树或茶树 EO 与 X 射线照射的联合处理，在剂量率为 0.76 和 0.19 kGy/h 时，桉树 EO 的 LD 值分别为 746.02 和 737.1 Gy，茶树 EO 的 LD 值分别为 632.03 和 615.5 Gy。总体而言，X 射线联合治疗 LD 值显着高于 γ 射线照射（治疗效果较差）。 与γ射线照射不同，X射线照射的剂量率不影响联合治疗的疗效。伽马射线或 X 射线照射以及植物环氧乙烷（例如桉树或茶树环氧乙烷）单独或组合施用是有效的杀虫处理。辐射和环氧乙烷的协同效应可能取决于源和剂量率。我们的结果表明，使用较高剂量率的高能 γ 射线照射，与使用较低剂量率的高能 γ 射线照射或低能 X 射线照射相比，EO 对水稻的协同作用更有效（较低的 LD 值）。