Alternative hosts of the egg parasitoid [Ooencrytus pityocampae Mercet (Hymenoptera: Encrytidae)] of the pine processionary moth [Thaumetopoea pityocampa (Den.&Schiff.)] and its biology on Graphosoma lineatum (L.) (Hemiptera: Pentatomidae) in laboratory conditions

This study was carried out to determine the parasitization efficiency and parasitization duration of Ooencyrtus pityocampae (Mercet) (Hymenoptera: Encyrtidae) which is an important egg parasitoid of the Pine Processionary Moths [Thaumetopoea pityocampa (Den&Schiff.) (Lepidoptera: Notodontidae)] on the eggs of Graphosoma lineatum (L.) (Hemiptera: Pentatomidae). Studies were carried out in climate room that set to 25±1°C temperature, 65±5% humidity and 16:8 L:D conditions. One generation completion durations (days), egg parasitization ratios (%) and adult parasitoid emergence points were determined at various durations (24, 48 and 72 hours). According to findings, a spiny egg-stalk, 0.560±0.155 mm avg. in length extending to the egg shell, helps respiration of the parasitoid embryo is an important indicator of the host egg being parasitized. It is determined that O.pityocampae completed its development/a generation in 15-19 days while G.lineatum completed a generation in 7-8 days, and oviposited during a 30-day oviposition period. Also, in case of the host eggs presented to O.pityocampae adults with 24, 48 and 72 hour-periods, high parasitization ratios (94,03-99,38% avg.) were occurred in all parasitization periods. However, in case of parasitoid emergence duration being important, the shortest parasitoid emergence duration was 14.97±0.447 days when the host eggs were exposed to the parasitoid within 48 hours. Consequently, in case of mass production of O.pityocampae on G.lineatum eggs, 48-hour parasitization duration may be much efficient owing to both high parasitization ratio and shorter development duration of the parasitoid.