Bacterioses of woody plants in the local urban phytocenoses of Kyiv: Symptoms, etiology, and distribution

Urban ecosystems of modern cities are characterised by a high level of anthropogenic load, which negatively affects the state of green spaces. Woody plants are particularly vulnerable to negative impacts, which occupy a key role in ensuring the ecological stability of the urban environment. The phytosanitary condition of trees is an important indicator of the health of the city ecosystem; therefore, its monitoring and analysis are urgent tasks in modern ecology. The aim of the study was a comprehensive study of the bacteriosis of woody plants in local urban phytocenoses of Kyiv, including the analysis of the characteristics of symptoms, identification of pathogens, and patterns of disease spread. The research was conducted during the 2024 growing season in the green areas of the “Respublika Park” and “Retroville” shopping and entertainment complexes. The work used modern microbiological methods for identifying pathogens of bacteriosis, as well as classical methods of phytosanitary inspection. To clarify the current systematic position and current name of taxa, information from the interactive databases “Index Fungorum” and “International Committee on Systematics of Prokaryotes” was used. It was investigated that the sanitary condition of the urbophytocenoses of the “Respublika Park” and “Retroville” shopping centers is characterised by a high degree of weakening of Acer saccharinum L. trees and a medium degree for Ulmus laevis Pall. It was established that the main cause of weakening of the trees is bacteriosis, the causative agent of which is the bacterium Lelliottia nimipressurallis (Carter 1945) Brady et al. 2013, which was confirmed by the polymerase chain reaction method. It is noted that the primary signs of damage to the bacteriosis of Acer saccharinum and Ulmus laevis urbophytocenoses are superficial peeling cracks, swelling of the bark, and the release of exudate. Secondary signs of damage were deep ulcers, necroti sation of wounds, and settlement of wood-destroying fungi. It was shown that the degree of development of bacteriosis on Acer saccharinum trees is 2 points and is characterised as rapid, and for Ulmus laevis trees – 1 point and is characterised as gradual. Thus, this study allowed to obtain a comprehensive picture of the spread and impact of bacteriosis on woody plants of urban phytocenoses of Kyiv, and also, based on the described features of symptoms – key diagnostic elements to develop measures for timely phytosanitary management of the condition of green spaces of cities to improve the ecological state and improve the quality of life of residents