The study of the leafmining moth of the chestnut miner (Cameraria ohridella Deschka & Dymić, 1986) was carried out through the planting of the common horse chestnut (Aesculus hippocastanum L.) in the Main Botanical Garden of the Russian Academy of Sciences. The effect of various degrees of insolation of horse chestnut plants on leaf morphology and the composition of secondary metabolites, as well as the relationship of these parameters with the number and density of C. ohridella populations during the growing season, was studied. The solar influence, it was noted, had a significant impact. Thus, the largest number of the pests was recorded on the leaves of the sunlit side of the tree crown, and the smallest on the leaves of the shady part of the crown. The low content of polyphenols in the pool of secondary metabolites in the tissues of the A. hippocastanum leaves did not deter C. ohridella and poorly protected the plants from this miner, while the significant content of carbohydrates in the leaves reduced the resistance of chestnut plants to damage by the Ohrid leaf miner.

The susceptibility of seven species of chestnuts to the horse chestnut leaf miner was studied in the arboretum of the Main Botanical Garden of the Russian Academy of Sciences (MBG RAS), taking into account their interspecific characteristics. Using pheromone delta traps, the highest number of Cameraria ohridella moths was shown for Aesculus hippocastanum and the lowest for Aesculus chinensis. A number of anatomical parameters of leaves were investigated, such as the thickness of the epidermal cell wall and the thickness of the palisade and spongy parenchyma layers. As a result, it was shown that the most infected chestnut species had a greater thickness of the nutritious parenchyma tissue. No dependence was found between the degree of susceptibility to the horse chestnut leaf miner and such indicators as the content of chlorophyll a + b and carotenoids in the leaves of seven species of chestnuts. Nevertheless, resistance of different species of the genus Aesculus to Cameraria ohridella under increased tannin content in leaves has been shown. Evaluation of phenolic compounds and flavonoids has not established their reliable role as repellents. The high levels of carbohydrates found during the study contributed to increased susceptibility to the horse chestnut leaf miner.

It is generally accepted that mycobiota diversity in urban greenhouses is poorer than in natural ecosystems, but our knowledge on this field of research is fragmentary. Here, we present the results of a long-term study of aphyllophoroid macrofungi (Basidiomycota) forming fruitbodies on non-native sub/tropical woody and herbaceous plants in the greenhouses of Saint Petersburg, Moscow, and Ekaterinburg botanical gardens located in the hemiboreal vegetation subzone of Eastern Europe. Over 20 years of research, fruitbodies of 58 species of aphyllophoroid fungi have been identified. Fungal species that developed on the wooden structures of greenhouses and building materials made of local wood are discussed separately. The list of fungi on non-native substrates is dominated by saprobes (93.1% of total list) as well as mycorrhizal with basidiomata on plants (8.6%). Phytopathogens have the lowest number (7.0%), and ¾ of species are widespread locally. Non-native plants are dominated by native fungal species (78.9%), while the percentage of non-native species is low (21.1%). In the three surveyed cities, the area of the studied greenhouses is 2.8 ha, and not a single species of fungi has been found twice on the same substrate. Half of the identified species are characterized by a single specimen (29 species/50.9%). Hymenochaete rheicolor was discovered in Russia for the first time and its known distribution is discussed. Only six (Antrodia gossypium, Hyphodontia arguta, Lyomyces sambuci, Peniophora cinerea, Ramariopsis kunzei, and Trechispora farinacea) local species (10.5%) were collected in all the three cities. The α-diversity of mycobiota (mean number of species per site, Shannon Index, and Menhinick Index) in the Ekaterinburg’s greenhouses is 1.2–3.0 times lower compared to suburban forest parks and old-growth natural forests, while β-diversity (Whittaker Index, Jaccard Index, and Morisita–Horn Index), on the contrary, is 2.1–7.7 times higher. With the plants’ age, the probability of detecting fungi on them increases significantly. In greenhouses, phytopathogenic aphyllophoroid macrofungi are collected on woody plants only, but the probability of their development is not related to the plants’ age.

Typhulaceae Jülich is one of the cold-adapted fungal families in basidiomycetes. The representative genera, Typhula (Pers.) Fr. and Pistillaria Fr., are distinguished by the discontinuity between stems and hymenia in the former and the continuity in the latter (Fries 1821). This taxonomic criterion is ambiguous, and consequently, the view of Karsten (1882) has been widely accepted: Typhula develops basidiomata from sclerotia, while basidiomata develop directly from substrata in Pistillaris. However, Corner (1970) observed basidiomata of Pistillaria petasitis S. Imai developing from sclerotia in Hokkaido, Japan. We later recognized that P. petasitis basidiomata also emerged directly from substrates on the ground in Hokkaido. An aberrant form of Typhula hyperborea H. Ekstr. was found in Upernavik, West Greenland. This specimen had a stem-like structure on a Poaceae plant, and sclerotia developed on its tip. Similar phenomena were found in other Typhula species in Japan. In this study, we aimed to elucidate the life cycle plasticity in the genera Typhula and Pistillaria through the interactions between their ecophysiological potential and environmental conditions in their localities. We collected and prepared strains of the above fungi from sclerotia or basidiomata, and we elucidated the taxonomical relationship and determined the physiological characteristics of our strains. Our findings imply that both Typhula and Pistillaria have the potential to produce sclerotia as well as the capacity for mycelial growth at ambient air temperatures in each locality where samples were collected. These findings suggest that Typhula spp. develope basidiomata not only from the sclerotia dispersed by the basidiospores but also from mycelia generated by the spore germination, which formed basidiomata multiple times, depending on their growth environments.

The purpose of this publication is to show the history of the taxonomy of the Typhula ishikariensis complex and to provide more detailed geographical descriptions of those fungi in Russia. Three features on the description of this complex species are noted: morphological, crossing and molecular. Often, species described on different host plants have been recognized as synonyms of another previously described species, for example, T. humulina isolated from hop rhizomes and T. graminearum from first year seedlings of Pinus sylvestris and grass weeds have been synonymized with Typhula idahoensis. The latest work by Hoshino et al. distinguished four taxa (three species) based on dendrograms obtained by ITS and ribosomal DNA sequencing, crossing results, morphological and physiological characters: T. ishikariensis var. ishikariensis, T. ishikariensis var. idahoensis, T. hyperborea, and T. canadensis. T. ishikariensis var. idahoensis was found only in North America, and the last two species (T. hyperborea and T. canadensis) mainly in areas with extreme winter conditions. In Russia, Typhula ishikariensis var. ishikariensis, was recorded in the European part of Russia beyond the Arctic Circle: Apatity (Kola Peninsula), in places with a temperate climate: Moscow, St. Petersburg, the republics of Chuvashia and Mari El; and in Asia with a more severe climate: Sverdlovsk Region, Novosibirsk, Irkutsk Region (Hamar-Daban) and Sakhalin. T. canadensis and, presumably, the oldest T. hyperborea, inhabit mainly in areas with unstable and severe winter climates. T canadensis in Russia was noted by us in Asia in the Baikal region in the Ice Age refugium Khamar-Daban, Kamchatka and Sakhalin, and T. hyperborea in Asia in the Sverdlovsk region, Novosibirsk, Kamchatka and Chukotka (Anadyr), along with the European regions of Russia with a temperate climate in the Volga republics of Mari El and Tatarstan. These areas are characterized frequent autumn frosts, which promoted competition with another snow mold pathogen, the necrotroph Sclerotinia borealis. Underground damage of plant tissues, such as tulip bulb bases and roots, and hop rhizomes by T. ishikariensis var. ishikariensis occurred only in Russia. Perhaps the diversity in winter climate evolved and preserved diverse taxa, including ancestral forms. Obviously, such climatic fluctuations evolved organisms capable of survival under unstable stressful conditions, especially when climatic conditions change.

Results of a five-year study of phytophages and phytopathogens in the Moscow region on two invasive species of the genus Impatiens L. (Balsaminaceae): I. parviflora DC. and I. grandi ora Royl. are presented. The damaging complex consists of representatives of herbivorous polyphages, fungal pathogens, phytoviruses and indicates the adaptation of autochthonous phytotrophic organisms. 6 phytophages and 4 pathogens of fungal diseases at I. parvi ora, and 5 phytophages, 4 fungal phytopathogens and 3 phytoviruses at I. glandulifera were found. During the study period, there was no critical increase in the density of populations of harmful arthropod species and the development of epiphytoties.