Parassitizzazione delle uova di Thaumetopoea pityocampa: modificazioni conseguenti al potenziamento artificiale di Ooencyrtus pityocampae

In 1991 a trial was carried out to obtain the biological control of Thaumetopoea pityocampa by augmentation of its egg parasitoid Ooencyrtus pityocampae. About 19,000 specimens of 0. pityocampae, mass-reared on Nezara viridula eggs, were released in a young pine stand in central Italy (Lazio). After the augmentation of existing 0. pityocampae population, egg parasitism due to this species increased about 10 times and the percentage of total parasitized eggs rose 8 times in respect to the original amount. Egg parasitism percentage was still high in the following year. Eggs laid on Pinus halepensis were constantly the most parasitized and exceeded the 50% level immediately after augmentation.