Journal Article

The sex pheromone heptacosane enhances the mating competitiveness of sterile Aedes aegypti males

Li, Ni, Wang, Lin-Min, Zhang, Mao, Tang, Qi, Niu, Jia-Xuan, Wang, Duo-Quan, Xiao, Liang, Liu, Miao, Zhang, Chao, Peng, Zhe-Yu, Deng, Sheng-Qun, Zhou, Qing-Ya, Lu, Hong-Zheng

2023

Overview

Background Aedes aegypti is a vector that transmits various viral diseases, including dengue and Zika. The radiation-based sterile insect technique (SIT) has a limited effect on mosquito control because of the difficulty in irradiating males without reducing their mating competitiveness. In this study, the insect sex pheromone heptacosane was applied to Ae. aegypti males to investigate whether it could enhance the mating competitiveness of irradiated males. Methods Heptacosane was smeared on the abdomens of Ae. aegypti males that were allowed to mate with untreated virgin females. The insemination rate was used to assess the attractiveness of heptacosane-treated males to females. The pupae were irradiated with different doses of X-rays and γ-rays, and the emergence, survival time, egg number, and hatch rate were detected to find the optimal dose of X-ray and γ-ray radiation. The males irradiated at the optimal dose were smeared with heptacosane, released in different ratios with untreated males, and mated with females. The effect of heptacosane on the mating competitiveness of irradiated mosquitoes was then evaluated by the hatch rate, induced sterility, and mating competitiveness index. Results Applying heptacosane to Ae. aegypti males significantly increased the insemination rate of females by 20%. Pupal radiation did not affect egg number but significantly reduced survival time and hatch rate. The emergence of the pupae was not affected by X-ray radiation but was affected by γ-ray radiation. Pupae exposed to 60 Gy X-rays and 40 Gy γ-rays were selected for subsequent experiments. After 60 Gy X-ray irradiation or 40 Gy γ-ray irradiation, the average hatch rate was less than 0.1%, and the average survival time was more than 15 days. Moreover, at the same release ratio, the hatch rate of the irradiated group perfumed with heptacosane was lower than that of the group without heptacosane. Conversely, the male sterility and male mating competitiveness index were significantly increased due to the use of heptacosane. Conclusions The sex pheromone heptacosane enhanced the interaction between Ae. aegypti males and females. Perfuming males irradiated by X-rays or γ-rays with heptacosane led to a significant increase in mating competitiveness. This study provided a new idea for improving the application effect of SIT. Graphical Abstract

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Adults / Aedes - radiation effects / Aedes aegypti / Animal reproduction / Animals / Aquatic insects / Behavior / Biological fertilization / Biomedical and Life Sciences / Biomedicine / Competitiveness / Control / Courtship of animals / dengue / Disease transmission / Eggs / Emergence / Entomology / Feasibility studies / Female / Females / Gamma rays / Hatching / Heptacosane / Human diseases / Humans / Infectious Diseases / Infertility, Male / Insect control / Insect sterilization / Insects / Insects as carriers of disease / insemination / Irradiation / Male / Male mating competitiveness / Male sterility / Males / Mating / mosquito control / Mosquito Vectors - radiation effects / Mosquitoes / Parasitology / Pest control / Pesticides / Pheromones / Physiological aspects / Pupa - radiation effects / Pupae / Radiation / Reproduction / Reproductive behaviour / Risk factors / Sex / Sex Attractants - pharmacology / Sex pheromone / sex pheromones / Sexual Behavior, Animal - radiation effects / Sterile insect technique / Sterility / Sterilized organisms / Survival / Tropical Medicine / Variance analysis / Vector-borne diseases / Veterinary Medicine/Veterinary Science / Viral diseases / Virology / Viroses / Virus diseases / X ray irradiation / X rays / X-radiation / X-ray / Zika Virus / Zika Virus Infection / Zoological research / γ-ray