Studies of Polygraphus proximus Blandf. (Coleoptera, Curculionidae: Scolytinae), the invasive pest of Siberian fir, conducted in 2013-2019 in the middle taiga forests of Kolpashevsky, Verkhneketsky, Parabelsky, Kargasoksky districts of the Tomsk Oblast. The alien bark beetle was found on the territory with geographical coordinates 58°20΄02″– 59°00΄24″ N, 80°39΄21″–84°44΄40″ E in the stands of different composition, age and health condition. P. proximus colonized fir in a complex with aboriginal species of stem insects, longhorn beetle Monochamus urussovi, bark beetle Xylechinus pilosus and Buprestidae. Very rarely it infested trees independently, using mainly thin-dimensional weakened trees, sometimes large undergrowth. The number of trees infested by P. proximus in stands is small, which is explained by its relatively recent penetration into the northern regions and the lack of favorable feeding and temperature conditions for reproduction. The population density of parent generation on most model trees was characterized by low (0.19–2.9 families/dm2) and average (3.2–5.0 families/dm2) values, and only on some trees reached high values (5.3–7.4 families/dm2).The number of the daughter generation on different trees varied from low (1.9–14.8 individuals/dm2) to medium (20.3–29.8 individuals/dm2) and high (34.3–64.9 individuals/dm2). The energy of reproduction ranges from low (0.9) to medium (1.3–2.9) and high (4.7– 22.9). The range of variability of P. proximus population indicators could be due to both different intensity of interspecific relationships with aboriginal stem dendrophages, and the weakening of intraspecific competition and the press of natural enemies during a low population density of invader.

Almost simultaneously in 2016, along the northern border of the range of spongy moth Lymantria dispar (L.) over a huge area of more than 1000 km in the longitude direction from Yekaterinburg (N 56.5 °, E 60.4°) to the village of Kyshtovka (Novosibirsk region), (N 56.4°, E 76.6°) the outbreaks of the spongy moth have formed on hundreds of thousands of hectares. Such synchronicity in the occurrence of outbreaks can indicate the impact of a single modifying factor. The purpose of the study is to identify a single modifying factor that could provoke an outbreak of the spongy moth, based on an analysis of weather conditions in the growing seasons preceding the formation of outbreaks and during their implementation. Over the large area covering the Trans-Ural and West Siberian populations, in their northern part, the scenarios of weather conditions changes before and during the implementation of the outbreak of 2016–2018 differed significantly in terms of humidity conditions but were similar in terms of heat availability. For two or three years, the heat availability was significantly lower than normal, then become the season with heat availability significantly higher than normal and a sharp increase in population density that provide the severe defoliation of stands for the next year when the heat availability of the growing season returns to normal. That indicates the differences in modifying factors provoking outbreaks at the north of the range of the spongy moth in comparison with southern parts of the range of this species. Possibly, growing seasons with low heat availability lead both to the elimination of the offspring of individuals in the population with a long duration of development till the imaginal stage, and to a reduction in the duration of development at the larval stage of individuals that have received the necessary, but an extremely small amount of summer-autumn temperatures to complete early embryonic development and preparation for wintering. With the onset of the growing season with a heat availability significantly higher than normal, the elimination of individuals with a longer duration of development decreases, which results in the population density increase and significant defoliation in the next year.

The Cypress jewel beetle Lamprodila festiva (L.) is a dangerous pest of plants of the Cupressaceae family. For the first time, the dieback of Thuja and Juniperus from this pest was noted in Russia in 2013, and the species identity was established in 2016. The studies were carried out by the route method, on the territory of the Krasnodar and Stavropol Krais, the Republics of Karachay-Cherkessia, Crimea and Adygea, the Rostov Oblast during the vegetation seasons of 2017-2022. Volunteers from the indicated regions and regions bordering them were also involved in identifying the centers of the presence of the L. festiva. Since 2021, the cypress jewel beetle has been ubiquitous throughout the territory of the Krasnodar Krai and the Republic of Adygea. As of the end of 2022, the pest outbreaks occured in the Republic of Crimea, Rostov Oblast, Stavropol Krai, Karachay-Cherkessia and Kabardino-Balkaria. Observations in the cities of Shakhty, Kamensk-Shakhtinsky, Volgodonsk (Rostov Oblast), Volgograd, Elista, Astrakhan, Grozny, Makhachkala and Derbent show the absence of the pest so far. Invasion into new territories occurs mainly with planting material of fodder species. The main flows of planting material are directed to the north and northwest of the European part of Russia, somewhat smaller ones – to the west (Crimea) and east (Kalmykia, the republics of the North Caucasus, Volgograd and Astrakhan Oblast). Trophic relationships of the pest with plants of 19 species have been established. Not only typical forms are damaged, but also cultivars. Thuja occidentalis L. and its cultivars Smaragd, Brabant, Danica, Woodwardii, Thuja plicata Donn ex D.Don and its cultivars Atrovirens, Zebrina, Aurescens, Juniperus scopulorum Sarg. and its cultivars Skyrocket, Blue Arrow, Moonglow, Juniperus chinensis L. and its cultivars Keteleerii, Variegata, Pfitzeriana Compacta turned out to be the most preferable for colonization. The least preferred host species include Chamaecyparis pisifera (Siebold & Zucc.) Endl., Cupressus funebris Endl. and Platycladus orientalis (L.) Franco.

The number of instars of the Cydalima perspectalis caterpillars when feeding on Buxus sempervirens varies from five to eight. Caterpillars of the VIII instar were found in a single specimens in each generation. The time spent at the VIII instar, both in the first and second generations, was 8 days. The pupae in both cases turned out to be males. The sex ratio during pupation at the V instar was 1:1 in both generations, at the VI instar in the first generation – 1:1.7, and in the second – 1.3:1. During pupation at the VII instar, males dominated (1:2). The maximum percentage of pupation is observed at the VI instar, which turned out to be the most common older instar in the studied individuals of the box tree moth. Caterpillars of the boxwood moth hatched from the same egg cluster and under the same conditions developed asynchronously. The duration of the caterpillar phase varied from 18 to 29 days under the same temperature. The coefficient of variability for the period of caterpillar stage in the first generation was 11.7%, in the second 13.3%. At the same time, most caterpillars of the first generation at the I–IV instars, and in the second generation – at the I–V instars developed within two to three days. Biometric indicators of caterpillars in different instars were determined. The maximum growth rates of the head capsule were observed at the III instar. Some caterpillars of the first generation at the III and IV instars formed double-layered cocoons in which they stayed for six months, been alive.

Crimean pine Pinus nigra subsp. pallasiana has increasingly been introduced into crops in some regions of southern Russia, in particular in the Rostov region. There are no natural pine forests in the interfluve of the Don and Volga, but artificial plantings of this breed have been created here for more than 100 years. Here, often and on large areas, foci of mass reproduction of the red pine sawfly Neodiprion sertifer are formed. The first planting of Crimean pine showed that this pest did not damage it, preferring the Scotch pine Pinus sylvestris. This was the reason that the Crimean pine was increasingly planted on forest-cultural areas. To date, the share of Crimean pine plantings in the Sholokhov forestry has reached almost 30% of the total area of pine crops. The increase in the areas occupied by the Crimean pine led to the fact that soon the red pine sawyer began to damage it, and currently the foci of mass reproduction of the pest act both in the planting of ordinary pine and in the planting of Crimean pine. The conducted studies have shown that despite the development of a new forage breed for the sawyer in the region, he still continues to give preference to the common pine, initially settling it in mixed plantings. By the 13-year-old age of Crimean pine plantings, almost all trees are already inhabited by a pest, while the red pine sawyer masters the planting of ordinary pine almost completely, starting from the age of 5-6 years. The calculation of the number of eggs laid by females inside the needles on both types of pines was carried out. Statistically significant differences were not revealed, but at the same time, the number of eggs laid on one pine is slightly higher on the Crimean pine than on the needles of the common pine. It is suggested that the predominance of Crimean pine will lead in the coming years to the fact that the pest will damage this pine as much as it previously damaged Scotch pine.

Adbera quadrifasciata (Curtis, 1829) (Coleoptera: Melandryidae) fairly widespread in Europe. Until now A. quadrifasciata was not recorded east of the Asian part of Turkey. The species was collected in the Krasnodar Territory and is reported for the first time for the fauna of the Russia.

As a result of the three-years long fixed-rout survey ash back disease caused by invasive ascomycete Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz, et Hosoya was detected on the territory of 31 subjects of the Russian Federation for the first time. This territory is one fifth part of European range of Fraxinus excelsior. Ash dieback appeared to be widespread pathology of ash at all examined regions of Russia. Genetic material of this pathogen was found in 163 from 178 analyzed samples with disease symptoms. Overall occurrence of the disease was 96,7%. Ash forests of Central and Southern Federal Districts were characterized by relatively low level of ash trees infestation (19,7 and 13,6% accordingly) in comparison with Northern Caucasus and Volga Districta were tee infestation has reached 27,9 and 29,0% accordingly. Levels of tree infestation of the most common ash species F. excelsior and F. pennsylvanica are not significantly different: 17,8 and 21,2% accordingly. The luck of information about this prominent pathology of ash can be partially explained by masking of its symptoms by damage of ash trees caused by emerald ash borer Agrilus planipennis Fairmaire, distributed on the territory of 20 European subjects of Federation and also by often ground fires. There is an urgent need of including this pathogen into the list of partially distributed quarantine organisms on the territory of the Eurasian economic unit. The main efforts should be concentrated on discovery of pathogen resistant genotypes and populations of ash for producing resistant plant forms, creation of genetic reservation zones and seed orchards.

The composition of canker mycobiota on spruce trunks in the Lisinsky forestry (Leningrad region) was studied. Small cancers or parts thereof were placed in a humid chamber. Fungi were identified by morphological features. The most common fungi were Sorocybe resinae (Fr.) Fr. and Penicillium glaucoalbidum (Desm.) Houbraken & Samson. The occurrence of S. resinae was 75.9%. The fungus developed in the surface layers of the dried resin, and in the absence of resinification, this fungus was not observed. It can be concluded that the fungus S. resinae is an almost integral component of the mycobiota of a resinous cancer on a spruce trunk in the Leningrad Region. Until now, the fungus P. glaucoalbidum has been registered in Russia only as a saprotroph. The performed experiments have shown the presence of weak pathogenic properties in this species. The high occurrence of P. glaucoalbidum (41.4%) allows us to consider this fungus as a regular participant in spruce trunks canker. An experiment was laid to test the species isolated in pure culture (P. glaucoalbidum and Oidiodendron sp.) as possible causative agents of trunk cancer. In the forest stand, 20 trunks of spruce trees were inoculated with the fungal cultures. The cultures stimulated the secretion of resin, without causing the growth of necrosis beyond the boundaries of the inflicted wound. It has been suggested that a more thorough study of biota of necrosis-cancerous formations and especially its non-pathogenic part will allow us to more accurately understand the nature of this phenomenon.

In recent years, the general weakening and dieback of pine and spruce in the forest stands of the Leningrad region have been of serious concern. The main reasons for the weakening and death of forest stands are unfavorable weather and soil-climatic conditions, damage by insects and pathogenic organisms, and numerous anthropogenic factors. In order to determine the phytopathological condition and role of phytopathogenic organisms in the weakening and death of pine and spruce in the Leningrad Region, route surveys were carried out and 87 permanent plots established in June-August of 2021 (30 – in spruce stands of the Lisinsky Educational and experimental forestry) Educational and Experimental Forestry Unit, and 27 and 30 – in pine and spruce stands respectively in the northern part of the Karelian Isthmus). The survey of trees in the sample plots was carried out in accordance with the requirements of the ICP Forest methodology supplemented by the classical methodology of forest pathological surveys. The phytopathological condition of coniferous stands in the surveyed territories of the Leningrad oblast is estimated as weakened. The data obtained showed the uncertainty of estimates of the role of fungi in the drying of stands. The main types of dendropathogenic fungi were identified and cases of tree stand death associated with the spread of pathogens were analyzed. In the forests of the Leningrad Region, the most common diseases of pine and spruce were wound canker in spruce and pitch canker in pine, which lead to weakening and less often to death of trees. Wood destroying fungi were not very common, among them: Armillaria sp. (a complex of species of the order Agaricales Underw) which cause root and trunk rot and are often the cause of wind fall, weakening and dieback of trees; and Porodaedalea pini (Brot.) Murrill and Porodaedalea abietis (P. Karst.) which cause stem rot but occur singly and do not affect the phytopathological state of forest stands. The identified diseases contribute to the general weakening of forest stands and, as a result, to outbreaks of secondary stem pests. The data obtained showed the ambiguity of estimates of the role of fungi in the die back of stands. In the surveyed territories of the Leningrad Region, the phytopathological condition of coniferous stands has been described as healthy.

Sea buckthorn (Hippophae rhamnoides L.) is used in agroforestry of eroded lands and landscaping of settlements, as well as in the creation of industrial plantations. Sea buckthorn belongs to actinorhizal plants that form bacteriosymbiotrophic relationships between the root system and soil microorganisms, representatives of the actinomycetes order (Actinomycetales) of the genus Frankia. Under the conditions of different soilclimatic zones in the places of sea buckthorn growth, the associative microbiota is selected. Differences in the composition and structure of different microbiomes in the root zone of sea buckthorn for the Baltic, Siberian, Central Asian and Caucasian climatypes are shown. The factors (edaphic and biological conditions) limiting the growth of sea buckthorn in different soil and climatic conditions were determined. It has been shown that favorable conditions are created in artificial plantations of sea buckthorn for the accumulation and growth of soil pathogens from the genus Alternaria, Fusarium, Rhizopus, as well as a large set of mold fungi from the genus Aspergillus, Clonostachys, Cunninghamella, Mucor, Humicola, Penicillium, Paecilomyces.

Mycogenic xylolysis in Scots pine (Pinus sylvestris L.) in coniferous-deciduous forests of the Non-Chernozem zone is a complex biochemical process involving four groups of Aphyllophorales fungi (APF). The limiting conditions associated with the directed active growth of fungal mycelium inside the wood include illumination, access to moisture and air. With the development of mycogenic xylolysis, there is an increase in the biodiversity of AFG species, which reaches a maximum at stage III–IV. On a large data set of 119 model trees and 3512 basidiomes of xylotrophic basidiomycetes, it was shown that the fruit bodies of fungi are actively formed under abiotic stress and in subsequent seasons their number increases. The dominant position in the APF complex at stage II-III is occupied by the cellulose-destroying fungus Neoantrodia serialis [=Antrodia serialis], as well as the lignin-destroying fungi Stereum sanguinolentum and Trichaptum fuscoviolaceum. At stage III–IV of mycogenic xylolysis, the growth of Fomitopsis pinicola prevails, the strategy of developing wood of which is similar to N. serialis [=A. serialis]. In the process of biological decomposition of pine wood, different types of APF evolved according to different strategies for the development of the substrate, forming diseases of the type of white rot (annular corrosive) or brown rot (segmental corrosive). Our research has demonstrated the rapid development of the substrate of S. sanguinolentum, with a wide coverage of a large volume of the trunk not only along the perimeter, but also in the trunk core and further in the directions up and down inside the tree along the gradient of moisture and air. The strategy of Fomitopsis pinicola is different, and is related to the adaptation to the biochemistry of the substrate, which is why it is so widespread in many habitats and on different parts of the trunk of the scots pine.

The indicators of the development of the European spruce bark beetle in the outbreak foci of the Roshchinsky forestry have deteriorated significantly. The average energy of reproduction in 2022 was 1.5 (in 2021 for different generations – 6.0 and 4.7). The same indicators were typical for the spruce forests covered by the outbreak in 2022 with the expansion of the area of the outbreaks. The population density has increased. The bark beetle stock decreased to 400 thousand individuals/ha in the 2021 outbreaks and to 1300 thousand/ha in the 2022 outbreaks high and possibly higher. Some model trees died as a result of exclusively additional feeding of the European spruce bark beetle, which passed through the entire area of the bark from the base to 5 m in height and, possibly, higher. The colonization and successful development of the second generation are marked on the model trees. In some cases, the development of the second generation occurred simultaneously with the third sister generation, while in others only the development of the second generation was observed. The development indicators of different generations did not differ significantly. The 2022 growing season was significantly colder than the previous year. Nevertheless, the second generation, as well as in 2021, has been quite successfully formed. Populations of the European spruce bark beetle steadily switched to a development combining monovoltine and bivoltine variants. Previously, such a phenomenon in this geographical area was not observed. The transition to the bivoltine model of development of the typographic bark beetle in the Leningrad region corresponds to the same process taking place in the Scandinavian population of the European spruce bark beetle. The appearance of bivoltinity increases the likelihood of large-scale outbreaks of reproduction of this pest. Despite some expansion of the area of foci, it can be assumed that the outbreak will end in 2023. However, continuation or recurrence of the outbreak after a short period of time is likely with an increase in temperature in the first half of the growing season, the formation of windblows, and the intense impact of anthropogenic factors.

A field experiment using pheromone traps with nest-building beetles of the foureyed fir bark beetle Polygraphus proximus Blandford (Coleoptera, Curculionidae, Scolytinae) confirmed the presence of an aggregation pheromone in this species: wood blocks with males and with male + female pairs attracted significantly more beetles of both sexes into the trap. Wood blocks with males had the maximum attractiveness. Wood blocks with males and females attracted in average 2.5 times less beetles. Wood blocks with females and without insects did not differ in attractiveness from empty (control) traps. Thus, male beetles are the main source of aggregation pheromone in the four-eyed fir bark beetle. The reasons for the differences between our results and those previously published by other authors seem to lie in the behavioral responses of P. proximus beetles to differences in the concentrations of the emitted pheromone in nature and in the limited space of a laboratory experiment.

The prolonged action of the complex preparation Abazol on ophiostomy (ophiostomatoid) fungi spread by fir trees was evaluated by the four-eyed fir bark beetle (Polygraphus proximus Blandford). Abazol, susceptible to insecticide Abaside and fungicide Debacarb are intended for injection into tree trunks under the bark after tree injection. A month after the treatment of healthy trees with Abazol, they were inoculated with a live culture of the fungus Grosmannia aoshimae. Abazol rises from the injector along the length of the trunk in a strip of 7–9 cm wide. Inoculation is carried out within this strip. Phloem necrosis caused by the fungus around the inoculation point was measured after 4 weeks. Phloem necrosis caused by fungal inoculation did not differ in the control (untreated trees) and experimental (treated trees) variants and averaged 62–63 mm. This indicates that as early as a month after treatment, the growth of the fungus was not inhibited in the preparation lanes. Additionally, three months after treatment, bark samples were taken from one tree, from the area where the pesticide was passed. Mycological analysis showed the presence in the samples of ophiostomatid fungi – associates of the four-eyed fir bark beetle. Previously published results of studies on the effect of Abasol on this bark beetle showed its effectiveness immediately after use and prolonged protection of Siberian fir from this pest for 2 months. But in our studies, Abasol did not demonstrate prolonged protection against ophiostomatoid fungi spread by the four-eyed fir bark beetle. The absence of significant differences in the length of phloem necrosis caused by the inoculation of G. aoshimae mycelium between the control and the experiment indicates that the fungus could quickly spread in the area of the pesticide passage after 1 month.

The models describing the seasonal dynamics of the catchability of pheromone traps for the spongy moth Lymantria dispar (L.). are proposed. Records of the of the spongy moth populations catchability were carried out from 2011 to 2015 using milkcarton traps in the Khabarovsk Territory. The number of imagoes arriving to the traps was recorded at intervals of 2 to 7 days from mid-July to early September. To assess the impact of the weather, daily temperature data from the Khabarovsk weather station were used. A model of the flight dynamics of spongy moths’ males to pheromone traps is constructed. As variables of the proposed model, both the catch values and a number of the first differences in seasonal dynamics are used. The time series of the dynamics of moths catchability and the increase in catchability are considered as autoregressive series in which the current values of the model variables depend on k previous values. It is shown that the quality of the model and approximation to full-scale data is achieved when switching from a variable characterizing the dynamics of catchability to a variable characterizing the dynamics of the first difference in catchability. The paper considers the high-frequency characteristics of the series of seasonal dynamics of catchability, which turn out to be logarithmically linearly dependent on the catchability in the past and the current temperature of the medium. It is shown that to describe the seasonal dynamics of the series of the first differences in the catchability of pheromone traps for the spongy moth, an autoregression and distributed lag model can be used, linking the current increase in catchability with the increases in catchability in previous records and the current ambient temperature. The possibility of using the parameters of these models to assess the state of populations is discussed.

Bumblebees, as pollinators of many plants, are the most important ecological component of natural and natural-anthropogenic ecosystems. The purpose of the research is to identify the structure of the food reserve of bumblebees living in the forest biotopes of the Leningrad province, as well as to study the dynamics of its changes during the period of bumblebee activity from April to September. The food reserve of bumblebees of forest ecosystem of the studied area of the Leningrad province includes 81 species of plants belonging to 23 families, which is 43% of the total diversity of honey-bearing and pollen-bearing plants of the Leningrad province. According to the timing of flowering and the inclusion of species in the structure of the food supply, four periods can be distinguished: spring (April – May), early summer (June), summer (July – August) and autumn (September). The spring period is characterized by a low species diversity of the forage base. Early summer – a sharp increase in the species diversity of the food supply. Summer – stabilization at the level of maximum values. Autumn – a sharp drop in the species diversity of forage plants. Analysis of the structure of the bumblebee food supply shows that at the beginning of the first period (April), the core of the food supply are plants of Salicaceae. Starting from the second decade of May, the structure of the fodder base is being restructured, as a result of which a single dominant is not allocated. In June (the second period), Fabaceae become the nucleus, and in the third and fourth periods they are replaced by Asteraceae. The greatest species diversity is characterized by Asteraceae – 19 species. The second group (9 – 10 species) consists of Fabaceae and Lamiaceae. The third group (7 – 4 species) – Scrophulariaceae, Salicaceae, Rosaceae, Apiceae. 16 plant families are represented in the food reserve by 1 – 2 species. Thus, a group of 7 plant families accounts for 74% of the species diversity of plants in the food reserve of bumblebees.

Sundew, a representative of a group of more than 600 species of insectivorous plants, is a pioneer in the development of these territories with extreme conditions. The purpose of the work is to determine the species composition of insects in the catches of sundew and to identify the features of their disposal by a predator plant. In laboratory conditions, when analyzing long-term video recordings, it was established that the frequency of occurrence per 1 hour of recording and on the 1 leaf at 2021 turned out to be 0,091±0,017, at 2022 it was 0,179±0,040. From the analysis of laboratory observations, it follows that the dewdrop uses soil invertebrates as food objects, including springtails. There is an assumption that such nutrition is not only a laboratory phenomenon, but also occurs in the natural living conditions of the sundew.To verify this assumption, a photograph was taken of the growing area of the sundew in the Vishenskoye swamp of the State Natural Biosphere Reserve Kerzhensky. In the course of the analysis of the photographs, the number of small and large objects on each leaf of the sundews was leaked. Objects comparable in size to the heads and tentacles of a sundew were considered small. Large objects were considered those that remove from a quarter of the surface of the leaf to its entire surface. According to the results of the analysis of photographs in 2021, it turned out that small objects are found with a frequency of 0,850±0,032 on the plant and 0,142±0,015 on the leaf. Large objects – 0,493±0,041 on the plant and 0,083±0,014 on the leaf. According to the results of the analysis of photographs in 2022, small objects are found with a frequent 0,836±0,041 on the plant and 0,191±0,010 on the leaf, and large objects are found with a frequency of 0,504±0,035 on the plant and 0,117±0,009 on the leaf. In this way, in laboratory and field conditions, we were able to show that roundleaf sundew uses not only croup-flying insects as food objects, but also soil arthropods.