Promoting a new specie of Cotesia as first biological control agent against the Mediterranean corn borer, an expanding pest.
CoteBio aims to conduct the research and development necessary for a future use of Cotesia typhae nov. sp. (Hymenoptera: Braconidae), a newly characterized insect parasitoid species, as a new biocontrol agent against the maize stem borer Sesamia nonagrioides (Lepidoptera: Noctuidae). Four converging facts signal the timeliness of this proposal:
- The discovery of this new species of Cotesia which is strictly specific to S. nonagrioides in Africa, and which can develop on European populations of this host species;
- The expansion of S. nonagrioides populations in France due to milder winters, and the consequent losses in corn yield and quality;
- The difficulty to control the second generation of this pest, due to current regulation on insecticide use, prohibition of Bt corn and absence of efficient biocontrol agents;
- The increasing societal interest and need for healthier food.
So far, attempts to use a French endemic natural enemy against S. nonagrioides has failed because it could not be mass reared. C. typhae is a promising biocontrol agent because: (i) efficiency and possibility of mass rearing have been assessed for one sister species, C. flavipes, which is widely used against the sugarcane borer in Brazil; (ii) we expect no environmental risk because C. typhae is host specific.
Studies to achieve the goal of CoteBio are structured in two main complementary parts : the biology of host-parasite interactions, and the feasability of biocontrol.
The project is the first step towards the use of C. typhae for maize bio-protection against the Mediterranean borer. It is based on a wide knowledge of the ecology, population genetic, behavior and physiology of species of the C. flavipes complex. It will produce the report required for the authorization of C. typhae introduction in the environment. If successful, the biocontrol agent against S. nonagrioides will allow reducing chemical treatment of maize. This project will also contribute to understand behavioral and molecular processes at play in reproductive success and adaptation to new habitats, which are essential components of successful biological control programs.