Community-based mass production of MaviMNPV and its comparative efficacy against Maruca vitrata, cowpea insect pest

Résumé

Abstract

The specific entomopathogenic baculovirus Maruca vitrata multi-nucleopolyhedrovirus (MaviMNVP) is identified in Taiwan and introduced by the International Institute of Tropical Agricultural (IITA) in Benin for the microbial control of the cowpea pod borer M. vitrata. The effect of larvae starving and feeding substrates on the virus mass production was assessed under laboratory conditions and field conditions in two locations at Dassa (Odo-Otchèrè) and at Glazoué (Mangoumi). Furthermore, the effect of the storage of MaviMNPV in oil from neem was assessed at room temperature. The efficacy of the virus was also studied in field conditions in comparison with oil from neem, Decis (synthetic chemical) and untreated control. Results revealed that starving before virus infection; negatively affect the number of virus-dead larvae, the viral solution volume and its concentration. Non-starving larvae fed with 72hours pre-germinated cowpea seeds were the most effective for MaviMNPV mass production as well as in laboratory or in field conditions. MaviMNPV mass production in field conditions was a success and should be encouraged. Furthermore, storing MaviMNPV in oil from neem didn’t alter the virulence of virus within 7days. Cowpea yield was similar in plots treated with the different products but was significantly higher than untreated control plot. Data were discussed with regard to community-based mass culture of MaviMNPV and its combination with other products for Maruca vitrata management.

Keywords: MaviMNPV; Cowpea; Maruca vitrata; Bénin