With growing concerns about chemical insecticides, there is also growing interest in safer, natural alternatives. This study investigated the individual and combined effects of two promising eco-friendly alternatives, diatomaceous earth (DE) and 1,8-cineole, a plant-based essential oil component, on adults of Acanthoscelides obtectus under laboratory conditions. Against the maximum doses of both products (DE 800 ppm, 1,8-cineole 5 ppm), A. obtectus showed 100% mortality within the first 24 h. Although mortality at lower doses (DE 25, 50, 100 ppm, 1,8-cineole 0.600, 1.2 ppm) began from the first day, it was not as effective. In the combined application of 200 ppm DE and 2.5 ppm 1,8-cineole, the mortality rate was 73.33 ± 8.81%, representing the most effective outcome achieved with the application of relatively low doses of DE and 1,8-cineole. No F1 progeny was observed at any dose of DE or in the combined applications. In contrast, F1 progeny occurred only at three doses of 1,8-cineole (0.150, 0.300, and 0.600 ppm); however, the number of eggs and emerging adults was markedly lower than in the control group and showed a statistically significant difference. Overall, the results obtained from DE alone and DE + 1,8-cineole applications were more effective.
Evrim SÖNMEZ (Fri,) studied this question.