In the dissertation the ecological basis of the regulation of pests in field crops' agrocenoses by monitoring common and quarantine pests as well as establishing the causes of their excessive development and spreading in Ukraine and revealing new ways to limit their amounts in agricultural ecosystems were shown. The results of research of Climate change in Ukraine and their impact on the distribution of pests in agrocenoses were shown. The increasing of the sum of active temperatures caused spreading such dangerous diseases of field crops as septoria, root rot, powdery mildew pyrenophora and brown rust. Those diseases can significantly reduce yield and quality of plant products and cause increasing of biological contamination of agroecosystems. Distribution of phytophages of field crops was investigated. Established that zones of ecological optimum of various dominant species of phytophages are expanding northward because of significant warming in Ukraine. This leads to the alteration of the species' structure of dominant entomological complexes, namely population growth and warmness of chinch in Polissya and Forest-Steppe districts of Ukraine. The monitoring of limitedly widespread on the territory of Ukraine species of quarantine pests of field crops was carried out. It was found 12 species of weeds, among which deserve special attention: Ambrosia artemisifolia L., Acroptilon repens L., Sorghum halepense (L.) Pers., Cenchrus pauciflorus Benth., Solanum rostratum Dunal, and Cuscuta spp. (C. europeae, C. epilinum Weihe, C. campestris, С. trіfоlіі, C. monogyna, C. Lehmanniana); 4 types of diseases: Mycosphaerella linicola Naumov, potatoes cancer (Synchytrium endobioticum Percival), Potato Globodera spp. and Rhizomania of sugar beet (caused by Beet necrotic yellow vein virus); 5 kinds of pests: Western corn rootworm (Diabrotica virgifera virgifera Le Conte), potato tuber moth (Phthorimaea operculella Zell), South American Tomato Leaf Miner/Moth (Tuta absoluta Meyr.), Silverleaf whitefly (Trialeurodes tabaci Gen.) and western flower thrips (Frankliniella occidentalis (Pergande)). Determined that the revival of trade and import of seeds from other countries promotes penetration into the territory of quarantine species causes Rhizomania as well as South American Tomato Moth, western flower thrips and tobacco whitefly, and weakening internal quarantine measures causes the rapid spreading of not earlier widespread pests: Ambrosia artemisifolia L., Acroptilon repens L., Mycosphaerella linicola Naumov, potato golden nematode (Globodera rostochiensis (Wollenweber) Behrens Rol) and Western corn rootworm (Diabrotica virgifera virgifera Le Conte). For reducing the harm of soil phytophages and pathogens that are stored on the seeds and in the soil it is recommended mandatory pre-treatment of seed by protective stimulating compositions before sowing.
