No abstract

Adelgids are dangerous sucking pests of the conifers. Adelges pectinatae pectinatae and Pineus cembrae (Cholodkovsky, 1888) are noted throughout the Botanical Garden of Peter the Great on the conifers Abies sibirica, Pinus sibirica, and Pinus Banksiana. The application of entomopathogenic fungi that can penetrate into the galls of adelgids allows decreasing the usage of the chemical pesticides. Strain G-033 VIZR, which is effective against sucking insects and mites, was examined. Conifers infected by the adelgids were sprayed with the blastospore suspension (titer – 5x107 spores/ml). The number of Adelges galls was counted before treatment and weekly for a month. The effectiveness of spores on the 7th and 10th day was 20-44 %; the effectiveness of the chemical insecticide Actara was 52-99 %. By the end of the observations, the effectiveness of the biolpesticide reached 92-98% at all species of trees and was at the level of the chemical reference. The effect of the application of spores was registered over the next month. The ability of L. muscarium to cause mycosis was proved by isolating strain G-033 VIZR from the galls of Adelges infected by fungus. The strain G-033 VIZR of L. muscarium showed high efficiency and a prolonged effect on the Adelgids population of two species A. pectinatae pectinatae and P. cembrae.

The article provides an overview of the nematodes found in the greenhouses of the Botanical Garden of Peter the Great. The most common nematodes of the families Meloidogyninae, Heteroderidae and Aphelenchoididae.

In recent years, in the orangeries of the Peter the Great Botanical Garden, the affection of representatives of the Ericaceae family, the genus rhododendron (Rhododendron (L.) oomycete Phytophthora cinnamomi, has been growing. In the study of the rhizospheric soil of sick and healthy plants, a wide distribution of Phytophthora was found. representatives of this family. The dynamics of the spread of the disease from 2012 to 2019 is presented. The population of Phytophthora cinnamomi in the soils is unevenly distributed, changing its structure (abundance, survival, seasonality, life cycle) in accordance with various micro -phytocenoses. The population structure is governed by coenotic relationships with soil microorganisms. The Phytophthora cinnamomi population is “pulsating,” with a maximum population (in May-June) and a minimum in NovemberDecember. The creation of suppressive soils and suppression factors may serve as a preliminary strategy when creating measures to protect plants of the Peter the Great Botanical Garden. The results of studies of the effects of biological products (Vitaplan, Sternifag, Gliokladin) and fertilizers (Potassium humate, Ecofus) on the pathogen are presented. To increase immunity, resistance inducers (immunocytophyte, sillplant, chitosan) were used.

Abies spp. Pinus spp. Pinus pumila (Pall.) Regel Abies spp. Abies spp.