Mistletoe in the relations system of "host-parasite"

Objective – to identify the spread of mistletoe (Viscum) in the dendrological park Olexandria and city plantations in Bila Tserkva, analysis of connections mistletoe-host tree, mechanisms of trees drying affected by mistletoe. Material and methods. Objects of research were tree plantations in arboretum Olexandria, urban and suburban plantations of Bila Tserkva. Some studies were conducted in plantations in Ternopil, Ivano-Frankivsk and Zhytomyr regions during expeditions surveys in 2015–2016 years. Accounting of mistletoe was carried out in early spring and autumn, in leafless period with the help of four-point scale of I.D. Vasilenko and L.M. Filippova (2013). Results. Observed significant increase in the number of affected trees and the number of mistletoe in the trees. Most mistletoe host plants (28 species) are found in the park Olexandria. There is a massive dried peaks of affected trees and mistletoe drying of some of them, there is a prevails of drying trees in environmentally adverse ecotypes. Noticed in the last decade behavior change of V. austriacum (Red Book of Belarus, the IUCN Red List, European Red List, Annex I of the Berne Conference), which leads to a catastrophic shrinkage of Pinus sylvestris L., this may justify a principle of formation of the Red Book environmental and other registers. Conclusions. The spread of Viscum album and number of hosts types significantly increased in the area of research in the green plantations. Damage of the tree by mistletoe leads to their mass top drying. But now in the study area V. album is not the main and only one cause of death of trees – equally dry trees damaged by mistletoe and tree, not settled by it