Pojava ženki velikog smrekinog likotoča Dendroctonus micans (Kugelann, 1794) na vitalnim stablima kavkaske smreke u Artvinu, Turska

Abstract

Dendroctonus micans (Kugelann, 1794), which was first discovered in 1966 in Turkey, has established almost in all oriental spruce forests in the Eastern Black Sea region until the late 2000s. In its expanding front it is responsible for killing spruce trees representing millions of cubic meters of wood. In recent years, oriental spruce forests have endemic population of this pest. But extreme climatic conditions that cause extreme weather circumstances may trigger suitable environment that favors D. micans outbreaks. In this study, we aimed to examine tree vitality of naturally infested and uninfested trees in the forest. Field studies were performed at a pure spruce stand in Taşlıca Forest Sub-District, Artvin Directorate of Forestry in 2016. Both infested and uninfested trees were selected in the stand closure. One core per tree was extracted from 30 naturally infested and 30 uninfested oriental spruce trees at the same stand. Core samples were taken at the second week of September. Phloem thickness, recent tree growth rates, diameter of breast height and the average number of xylem cells in a radial file formed until the sampling date were studied. Phloem thickness, recent tree growth rates and number of xylem cells were higher in infested trees. Host selection of D. micans was discussed in relation to characteristics of infested and uninfested trees.