Structure, ooparasitoid spectrum and rate of parasitism of egg-batches of Thaumetopoea pityocampa (Den. et Schiff.) (Lep., Thaumetopoeidae) in Greece.
1990
Bellin S. | Schmidt G.H. | Douma Petridou E.
In the years 1988/89, 222 egg-batches of the pine processionary caterpillar Thaumetopoea pityocampa (Den. et Schiff.) collected in Greece were studied in the laboratory for one year. Data on structure and size of the batches as well as a method rendering quit accurate estimates of the number of eggs per batch are presented. Altogether 10 871 parasitoids belonging to 6 species of Chalcidoidea emerged from the samples. The three most abundant species were Eutetranychus servadeii (Dom.), Ooencyrtus pityocampae Mercet and Eutetranychus sp. near servadeii. In the samples collected on Kassandra (K1) and on the Peloponnes (P) in autumn 1988 shortly after oviposition, the number of emerging primary parasitoids was largely related to the duration of field exposure of the batches. Caterpillars hatched from 67 per cent of the eggs of these sample units. In egg-batches collected on Kassandra after 7 months of exposure in the field (K2) a much greater parasitoid impact was observed. Not only did they yield more adult parasitoids throughout the first year. A striking difference was the much higher proportion of eggs without hatching or emergence holes, a majority of which showed signs of parasitoid attack. Only 4 per cent of the eggs appeared to be sterile after one year. Host mortality in the K2 egg-batches was calculated to be 63 per cent.
اظهر المزيد [+] اقل [-]الكلمات المفتاحية الخاصة بالمكنز الزراعي (أجروفوك)
المعلومات البيبليوغرافية
تم تزويد هذا السجل من قبل Wolters Kluwer