Combination of Steinernema carpocapsae (Weiser) and pheromone lure: a promising strategy for biological control of the banana black weevil Cosmopolites sordidus (Germar) on bananas in Martinique
Résumé
Cosmopolites sordidus (Germar, 1824) is one of the major pest of bananas in the Caribbean. Several techniques can be applied to avoid use of insecticides. On one hand, laboratory studies have shown that some specific strains of Steinermema spp. could contribute efficiently to the control of this pest. Unfortunately, field applications of formulations of S. carpocapsae often give inconsistent results due to formulation and conservation constraints. On the other hand, mass-trapping using pheromone lure has given good field results, excepted when the C. sordidus population levels were very high. ln this study, we used pheromone traps to contaminate weevils with entomopathogenic nematodes instead of killing them. During a 10 month study, we evaluated the interest of pheromone traps using pheromone lure on which we replaced each week new Galleria mellonella larvae previously inoculated with S. carpocapsae (Weiser). ln this experiment, promising results were obtained with a reduction of attacked plants from 98.5 to 40% and a reduction of the attack severity (according to Vilardebo's coefficient) from 42 to 23.