Method for disrupting the reproductive pheromone bond of the cotton bollworm on sunflower crops

Abstract

Background: Synthetic analogs of sexual pheromones provide an effective method of biorational control of the number of phytophagous insects based on the directed disruption of reproductive functions in populations of the target pest on the protected crop without affecting the integrity of the agrocenosis. The work aims to determine the biological effectiveness of methods of mass trapping and disorientation of the cotton bollworm (Helicoverpa armigera) to protect sunflower (Helianthus annuus) crops.Methods: The experiments were carried out in 2022-2023 in the Central Zone of the Krasnodar Territory, Russia in the stationary scientific crop rotation at the Federal Research Center for Biological Plant Protection, Krasnodar (2.5 ha) and the Kononenko farm, Novovelichkovskaya village, Dinsky district (10 ha). The biological effectiveness of elimination and disorientation methods was judged by the degree of damage to plants and buds. The disorientation effect was calculated by the number of males captured at the disorientation sites compared to the control sites.Result: The decrease in males’ search activity (disorientation effect) reached 85.3%. The damage to buds by the pest in this variant was 2.0% compared to 10.8% in the control group. In the mass trapping variant, it equaled 1.5-3.0 and 7.5%, respectively, indicating the prospects of including these techniques in the H. armigera biorational control system.Conclusion: Our findings could aid future research on insect chemical communication to develop effective biological control methods.Keywords: Biological plant protection; Sunflower; Cotton bollworm; Synthetic sex pheromones; Elimination; Disorientation; Biological effectiveness