Untersuchungen über Fichtengallenläuse, Dreyfusia spp. (Hom., Adelgidae) und deren Predatoren in der Nord-Türkei

2000

11 Lit. Ang.

Unselbständiges Werk

3718

200059704

In the East Pontic mountains at Giresun (Black Sea shore) three species of the genus Dreyfusia have been established: Dreyfusia nordmannianae Eckst. and Dreyfusia prelli Grosm. on Abies nordmanniana Link. and Picea orientalis Link. and Dreyfusia nov. spec. on Dreyfusia nordmannianae. The latter species, earlier known from Greece and the Balkans, but not yet described is most probably unholocyclic on fir. In the Zigana mountains between Trabzon and Gümüsane a species producing plenty galls on young Picea orientalis trees and closely resembling D. merkeri Eichh. has been observed. Further investigations are necessary to evaluate whether or not it lives unholocyclic on spruce. In the West Pontic mountains near Bolu Dreyfusia nordmannianae was intensively studied in twig infestations on Abies bornmülleriana Mattf. The pattern of attack differs greatly from the one experienced in central Europe in that almost exclusively the current year's shoots are attacked whereas the leader and the older twig axis remain free of attack. In Europe all parts of the trees are colonized. Considering the known facts about generation- and morph sequences, morph determimation and phenological behaviour of Dreyfusia nordmannianae the characteristics of their population dynamics in Turkey and the interactions of the curious mode of attack and the extraordinary efficiency of their special predators have been completely evaluated.