Evaluation of deterrent compounds targeting the two main pests of French hazelnuts: the brown marmorated stink bug (Halyomorpha halys) and the European hazelnut weevil (C

The primary mission of the lab of the "Association des Producteurs de Noisettes (ANPN)" is to minimise the impact of pathogen disease to the hazelnut quality and to select hazelnut cultivars. The ANPN has a strong experience in biocontrol and is a major actor in pest control in French hazel orchards. The ANPN is a partnership with INRAE since 1995 and the head leader of the European project against stink bugs (REPLIK) and against the nut weevils and the indian meal moths (BALAMITE). The ANPN also works on the evaluation of new hazelnut cultivars and their adaptability to various growing conditions such as planting density, rootstock effect, soil and climate conditions or phenology (OPTIVAR). More details at

Scientific background

In Europe, Curculio nucum is the main pest of hazelnuts. Adults drill through the shells to feed and/or lay eggs. Without control, yield losses can reach up to 80% ^1,2. In contrast to the weevil, Halyomorpha halys only feeds on hazelnuts. However, despite chemical control, up to 30% of hazelnuts may still be damaged. Phytophagous insects rely on plant-derived chemical cues (kairomones) to assess host quality, not only for adult feeding but, critically, to ensure the successful development of their offspring. Natural compounds or products could therefore be used to disrupt or manipulate the behavioural responses of both pests to hazelnuts. A set of candidate products has already been screened under this framework, with promising results.

Goals

The aim of this study is therefore to (1) evaluate the dose–response relationships of these products, applied alone or in combination, (2) test the formulations under field conditions, and (3) assess their potential phytotoxicity. In addition, the putative anti-oviposition pheromone of C. nucum could be investigated.

Rigor, autonomy, curiosity and critical sense; Knowledge in chemistry and/or in insect ethology would be an asset. A driving licence is required to access the field.