Holoborodko K. Invasive leaf-mining moths (Lepidoptera, Gracillariidae) in Ukraine: ecology, degree of invasion

The dissertation work is devoted to elucidating the bioecological characteristics of the existence and the influence degree of invasive leaf-mining insect species from Gracillariidae family (Lepidoptera) on dendroflora in Ukraine. Results were obtained for the first time that demonstrate the taxonomic, faunal and zoogeographic structure of the species complex in family of leaf-mining insects (Gracillariidae) in Ukraine. Biological characteristics of invasive insect species within this family of Lepidoptera were clarified. The invasion degree in five Gracillariidae species on the territory of Ukraine has been determined. The scientific work found the effect of Gracillariidae feeding on the forage plants. Caterpillars of invasive species affect the functional state of forage plants, which was confirmed by changes in soluble protein content, activity and isoenzyme composition of benzidine peroxidase during the growing season of these plants. The study of easily soluble protein dynamics showed their decrease when a high-degree leaf damage. An indicator of biochemical adaptation of plants to the diet of caterpillars of invasive leaf miners involves the restructuring of both the activity and the isozyme profile of peroxidase. Statistically significant differences were found for soluble peroxidase which activity increased by average of 2.1 times due to the high-level damage of leaves in forage plant by the caterpillars. High level of leaf damage by the phytophage was reflected in the change in the isozymic profile of benzidine peroxidase. The main pattern of negative effects of Gracillariidae caterpillars involves a significant increase in the activity of the most acidic molecular forms of cytoplasmic peroxidase in the leaves of forage plants. The results obtained demonstrate an activation of enzymatic antioxidant protection system in forage plants due to the damaging effect of Gracillariidae invasive caterpillars, which allows a plant organism to survive and complete the ontogenesis program in adverse conditions. The most significant factor in protecting cells from caterpillar activity involves an increase in the activity of guaiacol peroxidase, which indicates an increase in the cell barrier properties. It was established that the caterpillars of Gracillariidae invasive species effect significantly on the photosynthetic apparatus of forage plants. This effect was clearly determined with the fluorescence technique which was carried out using a portable fluorometer "Floratest". Analysis of the Kautsky curves in damaged and non-damaged leaves allow to state that the feeding of miners from the Gracillariidae family significantly affects the four main parameters of chlorophyll fluorescence intensity (CFI). The studies have shown that CFI technique allows to determine the general condition of plant organism in an express regime by evaluating photosynthesis as the main process in plant life. A range of parasitoids and fungal diseases of preimaginal stages of invasive development has been identified for the first time in Ukraine.