Farmers knowledge and control of two major pests: Helicoverpa armigera (Hübner) (Lepidoptera, Noctuidae) and Aphis gossypii (Glover) (Homoptera: Aphididae) in five agroecological zones in Benin (West Africa)

Abstract A survey study was performed in five agro-ecological zones in Benin to assess farmers' knowledge and perception on the identification, damage recognition, applied control methods of two cotton insect pests Helicoverpa armigera Hübner and Aphis gossypii Glover. A total of 200 farmers were interviewed in the five agroecological zones in Benin, using semi-structured questionnaire interviews. Results revealed sound knowledge of farmers on the identity of H. armigera and A. gossypii. Farmers easily recognized H. armigera through its damage on different plant organs while A. gossypii was known only at high infestation stage. Moreover, many crops are listed as host plants for H. armigera and A. gossypii with different economic injuries. Control of these insect pests was done mainly by the use of chemicals with various application numbers and frequencies. The most applied chemicals for the control of H. armigera on cotton were Nurelle D 236 EC in zone 4 and 6, Thunder145 O-Teq in zone 5 and Tihan 175 O-Teq in zone 2, while protection against A. gossypii was done using mostly Thian 175 O-Teq except in the zone 6 where Fanga was used. The time interval between two treatments was 3-14 days depending on the product in use, the target insect and the agro-ecological zone. The effectiveness of the different products was diversely appreciated. Farmers claimed to be aware of the so many side effects of chemicals application. In organic cotton area, alternative method consisting of the use of botanical extracts was being experimented.