A Study of Aqueous Plant Extracts of Moringa oleifera, Citrus limon, and Curcuma longa on Mealybugs (Maconellicoccus hirsutus)

Abstract

The pink hibiscus mealybug (Maconellicoccus hirsutus) is a key pest that damages crops and ornamental plants. Several chemicals are used to control this destructive insect; however, their extensive use can have environmental consequences and affect beneficial organisms. Botanical insecticides are therefore recognised as potentially safer options. The present study aimed to evaluate the efficacy of aqueous extracts of Moringa oleifera, Citrus limon, and Curcuma longa for controlling mealybugs. Plant materials were collected, dried, and ground, and the extracts were prepared using the Soxhlet method. The experiment was conducted in the laboratory using three concentrations (1%, 5%, and 10%). Ten mealybugs were placed in Petri dishes and treated with the extracts for different exposure periods. Mortality was recorded after 5, 10, and 15 minutes. Mortality generally increased with extract concentration and exposure time. The 10% Citrus limon extract produced the highest mortality (90% after 15 minutes), whereas the highest mortality observed for the other extracts was 70% after 15 minutes. These findings indicate that the tested plant extracts, particularly Citrus limon, showed insecticidal activity against mealybugs under the experimental conditions.