Study of the Oothecae During the Laying Period in the Stinking Locust, Zonocerus variegatus (Linnaeus, 1758) (Orthoptera: Pyrgomorphidae) in La Mé Region (Southeast, Côte d’Ivoire)

Background: This work aims to control certain egg-laying parameters in the stinking locust Zonocerus variegatus (L.) in order to determine the favorable times for a more effective management of this pest. Methods: Indeed, following rearing in cages of nymphs fed on leaves of Chromolaena odorata (C. odorata) (L.) RM King & H. Robinson and Manihot esculenta Crantz, adults were obtained and placed in pairs in tanks in order to have oothecae after mating. Findings: In total, 446 oothecae, which provided 13050 eggs, were collected. The egg laying parameters including the length, width, circumference and mass of the ootheca as well as the number of eggs per ootheca and the number of egg-layings per female showed significant differences depending on the month. Furthermore, the results revealed that females lay on average 48.33 ± 19.16 eggs per ootheca and the number of laid eggs per female is 1.65 ± 0.68 with a maximum of 4 eggs laying during the reproduction period. In addition, it is during the month of February that females lay more eggs per ootheca with 55.66 ± 21.24 eggs, compared to 37.51 ± 11.15 in June. However, the peak of ootheca laying is in June unlike in February where laying is lower. Finally, these results made it possible to deduce that the more eggs a female lays per ootheca, the fewer ootheca it can lay during its life. Novelty and applications: Thus, the period from January to June represents the ideal time to effectively combat this pest in the Côte d’Ivoire region.