Managing cold tolerance and quality of mass-produced Drosophila suzukii flies to facilitate the application of biocontrol through incompatible and sterile insect techniques – Suzukill

The recent invasion of fruit production areas by the Spotted Wing Drosophila fly (SWD), Drosophila suzukii, is a major concern for Europe’s soft fruit production sector. Chemical control proved to be ineffective and inadvisable due to regulation, pest resistance, and environmental and human health concerns. The classical biological control approach based on natural enemies might be challenging due to behavioural or physiological inadequacies. A promising alternative approach to fight against insect pests is the use of innovative biotechnology, such as mass-release of sterile insects. Sterile insects can be generated by irradiation (Sterile Insect Technique, SIT) or by Wolbachia-induced cytoplasmic incompatibility (Incompatible Insect Technique, IIT). These innovative methods represent a major breakthrough in pest management and have proved to be successful in controlling various invasive and/or pest species. However, these environmentally-friendly technologies require the development of mass-rearing of competitive insects at an industrial scale, as well as the ability to stockpile, handle and ship insects usually under stressing low temperature. The objective of the SUZUKILL project is to develop an alternative avenue for controlling SWD, initially in greenhouses, through the release of sterile insects produced via SIT and IIT. Protocols for mass-rearing and sterilization of SWD, as well as the adaptation of current quality control procedures for tephritid fruit flies, will be developed and validated in this project. We will identify critical elements of cold tolerance to better control this trait and develop quality management (including assessment of the genetic diversity and mating competiveness) in order to facilitate the implementation of these environmentally-friendly control methods. The specific expertise of French (UMR CNRS 6553 ECOBIO, Université de Rennes 1) and Austrian (Universität für Bodenkultur Wien, BOKU) partners will generate the fundamental and applied knowledge required for the management of cold tolerance and for an appropriate genetic/quality control strategy of the domesticated populations in the mass-rearing. The project will benefit from expertise and infrastructure of Insect Pest Control (IPC) Section from the Joint FAO/IAEA Division of Nuclear Techniques in Food & Agriculture for the implementation of a full SIT package. SUZUKILL will also benefit from recent developments made by the second French partner (UMR CNRS 5558 LBBE, Université de Lyon 1) in the field of IIT for this insect pest. By developing a common strategic research agenda, SUZUKILL project partners will coordinate transnational research program that will provide innovative, practical and biological solutions against the threat of SWD in Europe, and consequently, it will support and contribute to Europe’s phytosanitary scientific capability.