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BACKGROUND: The sterile insect technique (SIT) has proven to be an effective approach in managing the population of major invasive pests. Our previous studies showed that irradiation of Cydia pomonella males at a dosage of 366 Gy X‐rays resulted in complete sterility. However, the mating competitiveness of sterilized males is significantly compromised, which can be attributed to a decline in their ability to fly. RESULTS: In this study, we examined the flight patterns of both male and female adults of C. pomonella. The results revealed significant variations in the average flight speed of both genders at different stages of maturity, with females displaying longer flight duration and covering greater distances. Effect of irradiation on the flight performance of 3‐day‐old male moths was further evaluated, as they demonstrated the longest flight distance. The findings indicated a significant decrease in flight distance, duration, and average speed, due to wing deformities caused by irradiation, which also limited the dispersal distance of moths in orchards, as indicated by the mark‐and‐recapture assay. Reverse‐transcription quantitative polymerase chain reaction analysis revealed a down‐regulation of flight‐related genes such as Flightin, myosin heavy chain, and Distal‐less following radiation exposure. CONCLUSION: These findings demonstrate that X‐ray irradiation at a radiation dose of 366 Gy has a detrimental effect on the flight ability of male C. pomonella adults. These insights not only contribute to a better understanding of how radiation sterilization diminishes the mating competitiveness of male moths, but also aid in the development and improvement of SIT practices for the effective control of C. pomonella. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: The fall armyworm (FAW) Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) invaded Myanmar and China in 2018 and greatly impacted agricultural production and ecosystem balance in these areas. FAW is a migratory insect, but its seasonal migration pattern between the two countries has been largely unknown. From 2019 to 2021, we monitored the seasonal migration of FAW in the China–Myanmar border area using a searchlight trap, assessed the reproductive development status of female migrants and traced the migratory routes by trajectory simulation. Results: FAW moths were trapped by the searchlight trap in Lancang County (Yunnan, China) all year, with obvious seasonal differences in the number caught. There were small‐scale persistent trapping peaks in spring and summer, and obvious peaks in autumn; only a small number of moths were trapped in winter. Examination of the ovaries of female moths collected in different seasons showed that most females had matured, indicating that the moths were migrating and did not take off from the local area. In the migration trajectory simulation, FAW mainly migrated from Myanmar to Southwest China in spring and summer and back to Myanmar in autumn. Conclusion: Our findings indicate that FAW migrates between China and Myanmar according to the monsoon circulation, which will help guide cross‐border regional monitoring and management strategies against this pest. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: The sterile insect technique (SIT), involving the rearing of larvae for pupation followed by irradiating pupae, is employed for environmentally friendly invasive pest management. Despite its effectiveness, the cost of pupae production poses challenges for small farmers in developing countries. Alternatively, utilizing insect trapping techniques can capture abundant adult insects in their natural habitats, but application potential of adult SIT approach remains unclear., Results: We used the invasive pest Spodoptera frugiperda (Lepidoptera: Noctuidae) to assess the effectiveness of X-ray irradiated moths on their sterility rates, mating competitiveness, flight ability, and larval control efficiency in the field. Our findings revealed that optimal X-ray doses for 1-, 3-, and 5-day-old adult S. frugiperda were 154, 173, and 180 Gy, respectively. These doses rendered males more than 80.0% infertile and females nearly completely infertile. Significantly, the flight ability of sterilized males remained unaffected by sub-sterilizing doses of irradiation. Furthermore, in a release ratio of 16:1:1 (irradiated males-unirradiated males-unirradiated females), irradiated males exhibited the highest mating competitiveness (0.79). In the field-cage experiments, the corrected leaf protection rate and the corrected population decline rate in the 16:1:1 release plot were 60.50% and 74.21%, respectively., Conclusion: These findings suggest that radiation-induced sterility in adult S. frugiperda holds promise for practical applications, offering a conceptual framework and novel approaches for advancing radiation-based pest control technology. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)