Development of parasite complexes in the ecosystem of the rose garden of the main Botanical Garden of the Russian Academy of Sciences

Abstract

The article reports on studies (2011-2022) monitoring harmful organisms in the ecosystem of the rose garden of the Main Botanical Garden of the Russian Academy of Sciences. The studies yielded data on the detection of pathogens and pests, as well as the phenotypic manifestation of pathologies and lesions. A total of 21 species of pathogens and 16 species of phytophages were identified. The species composition of harmful organisms in the ecosystem of the rose garden was defined. It is shown that at the initial stage (2011- 2013) of ecosystem establishment, no external signs of viral diseases were observed, and a low level of fungal infections was noted. The development of such harmful pathogens as Peronospora sparsa Jacz., Sphaerotheca pannosa Lev., Phragmidium disciflorum James, and Ph. tuberculatum Mull. was controlled by culling plants of susceptible varieties. The predominant pathogens included Marssonina rosae (Lib.) Died., Phyllosticta rosae Desm., and Septoria rosae Desm., and the susceptibility of specific varieties to these pathogens was established. The populations of pathogens causing spot anthracnose (Sphaceloma rosarum Pass.), ascochyta leaf spot (Ascochyta rosicola Sacc.), and cercospora leaf spot (Cercospora rosicola Pass.) were slightly less common. A wide range of signs of viral infections was identified. Nine viruses belonging to five genera were detected. The frequency of their occurrence was analyzed, and the most common viruses were identified: Prunus necrotic ring spot ilarvirus, Apple mosaic ilarvirus, Tobacco ring spot nepovirus, and Arabis mosaic nepovirus. The species diversity of phytophages was noted: leaf beetles, snout beetles, leafroller moths, sawflies, blossom weevils, earwigs, moths, leafhoppers, aphids, and true bugs. It was found that damage to plants by a range of pests reached only an average level, except for individual varieties (Red Blanket and Prosperity). In general, the phytosanitary assessment of the rose gene pool of the garden according to the phytosanitary monitoring and integrated detection revealed a wide range of parasite complexes: fourteen types of pathogenic complexes, four types of entomological complexes, and five types of entomopathogenic complexes. The tactical and basic directions for control of harmful organisms in the ecosystem of the rose garden are discussed.