Assessment of Chestnut Gall Toughness: Implications for a Biocontrol Agent.

(1) , the biocontrol agent of the Asian chestnut gall wasp , is univoltine, but in NW Italy a small percentage of individuals exhibits a prolonged diapause, mainly as late instar larva. (2) In 2020, the diapause was investigated to evaluate its trend over the years. Due to the low survival rate of diapausing adults, the seasonal variation in the galls' toughness was evaluated, thus assuming that dry galls over time can negatively affect emergence.