Состояние фотосинтетического аппарата древесных растений при повреждении галловыми клещами

The paper presents data on the effect of gall mites on the state of the photosynthetic apparatus of the leaves of woody plants. The material was collected in the territory of the Dendropark of foresters of the Kirov region, located within the city of Kirov (a sub-zone of the southern taiga). To estimate the plant damage degree by gall mites, 100 leaves were collected from each site (10 leaves from each of 10 trees). At the sites with the greatest degree of damage by galling agents, 50 damaged and 50 unaffected leaves were randomly selected, whose length and width were measured. Leaves for the analysis of photosynthetic pigments were selected in the first half of the day (10:00–12:00). Leaf samples (0.15–0.25 g) were fixed with 100% boiling acetone. Plastid pigment content in the extraction was assessed using a SPEKOL 1300 spectrophotometer (Analytik Jena, Germany). Chlorophyll a, b, and carotenoids were analyzed at the wavelengths of 662, 644, and 470 nm, respectively. In the studied area, six species of gall mites widely distributed within the tree range were found on the leaves. Leaves on the linden were damaged by Eriophyes leiosoma and E. tiliae, on the bird cherry tree were by E. padi, on the aspen tree – by Aceria varia, on the rowan tree – by E. sorbi, and on the elm tree – by E. ulmicola. All the identified gall-forming species were monophagous. The most numerous species were the bird-cherry tick (E. padi) and the carob lime tick (E. tiliae). Leaf damage by gall mites did not significantly affect the size of the leaves, but led to changes in the pigment complex. The colonization of leaves with phytophages caused a decrease in the content of plastid pigments therein. Among the plants studied, the linden and bird cherry were more susceptible to damage by the galls; to a lesser extent, there were changes in the pigment fund under the action of the ticks of elm, ash and aspen. The revealed changes in the photosynthetic apparatus of woody plants when damaged by gall mites indicate the danger of this group of phyllophages for tree plantings in urbanized areas.