Effect evaluation of light-repellent technology application of Conopmorpha sinensis in field

【Objective】To study the effect of light-repellent technology application on Conopomorpha sinensis in different varieties of Litchi，and to investigate the effect of fruit yield and quality of Litchi and other insects，so as to provide technical support for the ecofriendly prevention and control technology of C. sinensis.【Method】A field experiment was performed in 2019-2020 with 3 treatment groups，night-light treatment（white LED light，wavelength range of 450- 465 nm），insecticide treatment，blank control on early-，middle- and late-maturing varieties of Litchi such as Sanyuehong，Feizixiao，Guiwei，Jizui，and Wuhe in Qinbei District，Qinzhou City，Lingshan County，Pubei County and Guiping City，Guangxi，China. The effects on other insects using the light-repellent technology was studied with light treatments （light-repellent technology experiment areas）and no-light treatments（insecticide control and prevention areas）in Lingshan County，Guangxi in 2020.【Result】The results showed that the prevention and control effects of light-repellent technology of C. sinensis were in the range of 95.57%-100.00%，and the average control effect was 98.50%. Meanwhile，the insecticide control effects were in the range of 76.61%-100.00%，and the average control effect was 93.24%，indicating 5.26% （absolute value）lower than that of light-repellent technology. The average yield of Litchi in the light-repellent technology areas was 11850.1 kg/ha，which was 752.4 kg/ha more than insecticide control under field conditions. There were 448 individuals of the Lepidoptera order，181 individuals of the Hemiptera order and 96 individuals of the Coleoptera order were collected in no-light treatments areas，269 individuals of the Coleoptera order and 165 individuals of the Hemiptera order were collected in light treatments areas.【Conclusion】The light-repellent technology can severely disturb the processes of mating and oviposition of C. sinensis through artificial light at night，and then the females will fail to produce offspring， achieving control and prevention effects. This technique is cost-effective，eco-friendly and easy to operate so it can be used as an alternatives to the use of chemical insecticides.