Effects of insecticides with different modes of action in the control of banana weevils <i>(Cosmopolites sordidus)</i> in Cameroon

Abstract

The aim of the study was to evaluate the use of insecticides with different modes of action on banana borer weevil. Insecticides with different modes of action were administered to banana weevils (Cosmopolites sordidus) in small containers (1 litre by volume) with perforated lids and monitored in the laboratory at room temperature and pressure. The insecticides were also applied on plantain plants (Musa sapientum) in a field trial following five treatments, each replicated three times arranged in a complete randomized block design. The laboratory and field results revealed that Counter^® - organophosphate with active ingredient Terbuphos (Hangzhou Tianlong Biotechnology Co., Ltd, China) and Regent^® - phenyl pyrazole with active ingredient fipronyl (Kalyani Industries PVT Ltd, China) were very effective (100% mortality) in the control of banana weevil. Insector^® - neonicotinoid with active ingredient imidaclopride (Heydchem Limited, China) showed a moderate effect (<20%) in the control of the weevil while Bromorex^® (botanical, with pepper and chilli extracts as active ingridients) proved to be a poor insecticide against this weevil. Bromorex^® also showed low non-mortality effects on the weevils with a high rate of egg laid and larvae emergence (17.3±4.5 and 1.6±0.4 respectively). Insector^®, Regent^® and Counter^® completely inhibited larvae emergence from eggs.

Key words: insecticide, efficacy, Cosmopolites sordidus, Banana