Diversification of entomofauna of Norway spruce Picea abies (L.) Karst. cones in the aspect of variable spruce stands masting in the Tatry National Park
In 1987–1992 the qualitative and quantitative share of insects infesting the Norway spruce Picea abies (L.)Karst. cones in the Tatry National Park was studied. Number of individuals dynamics of the chosen insects species was observed, herein the phenomenon of prolonged diapause. There were collected over 67,000 of insects belonging to 46 species from 5 orders. The most numerous and the most often met species were: Kaltenbachiola strobi (Winn.), Plemeliella abietina Seitn., Cydia strobilella L. The cones entomofauna collected in years with weaker intensity of spruce masting was over twice more numerous and more diverse in species (41 species) in comparison with entomofauna obtained from cones in heavy mast years (27 species). The cones from weak mast years were markedly more often and heavier infested with species: Torymus azureus Boh., Tetrastichus strobilanae Ratz., Venturia transfuga Grav., Triplatygaster contorticornis Ratz., Lycoriella solani Winn., Anogmus sp. aff. vala (Walker), Anogmus hohenheimensis Ratz., Strobilomyia anthracina (Czerny) i Torymus caudatus Boh. Trophic groups were distinguished, which were characterised with use of ecological indicators: permanency, domination and species diversity. Cones infestation with conophagous: P. abietina and K. strobi found out to be heavier in weak masting years, by 2.33% and 24.89% respectively; the similar tendency was with parasitoids and predators (by 7.7%). However, infestation with seminiphagous P. abietina was heavier (by 21.76%) in strong masting years. The population dynamics of P. abietina and K. strobi shows the tendency to alternating number growth and fall each 2 years. It was proved that part of the P. abietina and K. strobi population has ability to undergo prolonged diapause. K. strobi parasitoids have synchronized diapause with diapause of its host.
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