Trapping effect of LED lights with different wavelengths combined with sex pheromones on Conogethes punctiferalis

【Objective】The study aimed to screen the sensitive light wavelengths of the main Lepidoptera pest, the Conogethes punctiferalis, in orchards, and study the trapping effect of LED lights with different wavelengths combined with sex pheromones on the pest in the field.【Methods】Indoor experiments were conducted using an insect phototaxis behavior measurement device to select the wavelength light with the highest phototaxis response rate for C. punctiferalis from seven different wavelengths of light: purple light 430 nm, blue light 453 nm, greenish-blue light 492 nm, green light 533 nm, yellow green light 568 nm, yellow light 591 nm, and red light 620 nm. The differences in phototaxis rates between male and female C. punctiferalis were also identified, as well as the differences in phototaxis rates between C. punctiferalis exposed to 10 min, 20 min, and 30 min of LED lights. From March to October 2024, an annual dynamic survey of C. punctiferalis in Xinxiang peach orchard were conducted. Three triangular traps were placed and the number of C. punctiferalis on the traps were surveyed every 7 days. Fifteen trapping devices were placed in the peach orchard, including one single sex lure, seven single lamp lure, and seven lamp lure combined with sexual lure, all with three replicates. Comparing the field trapping effects of three different devices, including single lamp lure, single sex lure, and the combination of LED lights with different wavelengths and sex pheromones, on the C. punctiferalis, the best wavelength for trapping the C. punctiferalis was selected among the field single lamp lure and light lure combination devices.【Results】The wavelengths with higher phototaxis response rate of C. punctiferalis were as follows: 430 nm＞453 nm＞568 nm＞492 nm＞533 nm＞620 nm＞591 nm (P＜ 0.05). 10 minute exposure to the LED light resulted in the highest phototaxis rate of the C. punctiferalis (P＜0.05), and there was no significant difference in phototaxis rate between the male and female adults. The adult C. punctiferalis in the North of Xinxiang underwent four generations a year, and the number of traps reached peak in September, approaching 40. There were four peak periods: late April to late May, mid June to mid July, mid August and late September. From May 30 to July 4, 2024, a total of 116 insects, belonging to 4 orders and 8 families, mainly Lepidoptera and Coleoptera were attracted by 7 different wavelength LED light single lamp lure devices in peach orchard. 10 C. punctiferalis were trapped. The combination of lamp lure and sexual lure was used in peach orchard to lure a total of 597 insects, involving 4 orders and 7 families, mainly Lepidoptera and Coleoptera, and to trap 304 C. punctiferalis. The order of the number of C. punctiferalis captured by different devices from high to low was combination of lamp and sexual attraction＞single sex lure＞single lamp lure. Among the single lamp lure devices with different wavelengths of the light and the LED light lure+sex lure composite lure device, the purple light 430 nm had the best trapping effect on C. punctiferalis (P＜0.05), which was consistent with the preferred wavelength of indoor C. punctiferalis for phototaxis.【Conclusion】The combination of lamp lure and sexual lure increased the proportion of C. punctiferalis trapping by 42% compared with single lamp lure, and had a better trapping effect on the target insect C. punctiferalis. The combination of lamp and sex lure increased the proportion of insect trapping by 17% compared with single lamp lure, and had a better trapping effect on pests in peach orchard. The proportion of insect traps using a combination of lamp and sex lure decreased by 17% compared with single lamp lure, and had less impact on beneficial insects in peach orchard. The combination of lamp lure and lure was most effective in attracting target insects such as C. punctiferalis and other pests in peach orchards, and had less impact on beneficial insects in orchards. The adult C. punctiferalis had the highest preference for 430 nm ultraviolet light, and the combination of 430 nm ultraviolet LED light and sex pheromone trapping device had a better attraction effect on C. punctiferalis than single sex lure and single light lure.