Complexul de dusmani naturali ai speciei Eriopeltis festucae Fonscolombe (Homoptera, coccidae) in Romania.
1994
Moglan I.A.
Investigations were carried out in Uzlina zone of Danube Delta, in 1986, 1987, 1991 and Scobalteni-Podu Iloaie zone (Iasi county). 1021 females of Eriopeltis festucae, 4199 specimens parasitoids and 40 individuals of predators were analyzed. 17 specimens were identified, out of which 13 species are primary parasitoids, 4 species are secondary parasitoids and a predacious species. The average number of eggs laid by a parasitoid into a female of E. festucae varied between 4.8 in the case of species Trichomastus cyaneus and 13.7 eggs in the species Discodes encopiformis. The species Trichomastus albimanus, Tr. cyaneus, Tr. cyanifrons and D. encopiformis fly in July and the species Eunorus areolatus in August (Tab. VII). The ratio between sexes investigated 12 species of parasitoids and the ratio male to female was subunitary in all species analyzed, in all years (Tab. VIII). The total parasiting percentages were comprised between 9.3 percent in the locality of Scobalteni and 69 per cent in Uzlina, 1986 (Tab IX). In this complex of parasitoids there have been registered 15 types of combinations of parasitoids (Tab. IX). The secondary parasitoids insignificantly have reduced the number of primary parasitoids (Tab. X). The reckoning made has established that the parasiting caused the reduction of prolificity 89 percent an average.
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