Diversity and agronomic status of tomato and pepper fruit pests in two agro-ecological zones of Southern Cameroon: Western Highland and the Southern Plateau of Cameroon

摘要

Tomato and pepper are two major market gardening crops in Cameroon. In order improve pest insects control strategies, we assessed their diversity and evaluated their impact on yield losses in two agro-ecological areas of southern Cameroon. To achieve this, estimations of damages by visual observations were done twice per month from March 2010 to February 2011, in trap gardens set up respectively at Koutaba (Western Highlands) and at Okola (Southern Plateau). During each sampling, all fruits present in the garden were counted, those attacked or fallen on the ground collected and incubated in the laboratory for pest identification needs. Seven insect pests species belonging to two orders were identified. Among them, Dacus punctatifrons (Diptera-Tephritidae) and, Chrysodeixis chalcites (Lepidoptera-Noctuidae) were recorded on tomato, Ceratitis capitata (Diptera-Tephritidae), Chryptophlebia leucotreta and Leucinoides orbonalis (Lepidoptera-Pyralidea) on pepper while Spodoptera littoralis, and Helicoverpa armigera (Lepidoptera-Noctuidae) were recorded on both plants species. Fruit loses related to insects’ activities were greater in Koutaba (43-47%) than they were at Okola (28-33%). These rates varied with seasons. For instance, frequencies of fruits affected by D. punctatifrons, C. capitata, C. leucotreta were positively correlated to the abiotic factors, especially temperature and rainfall.