The results of a four-year (2017–2020) study of the phytosanitary state of forest biocenoses of specially protected natural areas (SPNA) of the Republic of Karelia are presented. Comprehensive research work was carried out in 2 reserves (Kivach and Kostomukshsky) and 2 national parks (Vodlozersky and Paanajarvi). In all protected areas, the presence of the bark beetle Ips typographus (Linnaeus, 1758) was recorded with its largest number in forest areas with disturbed stability (fires and windfalls). Beetles of the genus Monochamus Dejean, 1821 are also detected in all protected areas, but the largest number of the species M. sutor (Linnaeus, 1758), M. urussovi (Fisch., 1806), M. galloprovincialis (Oliv., 1795) are registered in the nature reserve “Kivach” and the national park (NP) “Vodlozersky”. Siberian silk moth Dendrolimus sibiricus Tschetw. and the gypsy moth Lymantria dispar (Linnaeus, 1758) were not detected in the studied SPNAs. In wood samples of coniferous species of European spruce (Picea abies) and Scotch pine (Pinus sylvestris) in the NP “Vodlozersky” a weakly pathogenic species of pinewood nematode was revealed Bursaphelenchus mucronatus (Mamiya & Enda, 1979). Among mycotic diseases, a wide spreading of the needle cast of pine Lophodermium pinastri (Schrad.) Chev., 1826 is noted.

Peach latent mosaic viroid (PLMVd) is included in the Common List of Quarantine Objects of the Eurasian Economic Union. The viroid infects stone fruit crop, causing significant crop losses. For a long time PLMVd was considered a monophage infecting only peach, but then it was detected on most other stone fruit crops, as well as on the pear. The viroid spreads with contaminated planting material, is easily tolerated by grafting with contaminated cuttings or buds, and very often by contaminated tools when pruning and grafting plants. 

In the course of the work of the Mycology Laboratory of FGBU “VNIIKR”, while studying the regulated products of cranberry seedlings samples from the Republic of Belarus, the fungus Diaporthe vaccinii Shear was detected and studied, which is a causative agent of blight of blueberry. The study describes the biological characteristics of the pathogen, the main damage symptoms on the Vaccinium genus berry crops and, in particular, on cranberry plants, methods of isolating and identifying the pathogen using culture morphological and molecular genetic methods; presents a comparative characteristic of the growth and development of the fungus on two nutrient media: potato dextrose and malt agar; the culture morphological characteristics of the fungus are described, as well as the morphometry of the structures – pycnidia and pycnospores. The identification of the pathogen was carried out on the basis of preliminary symptomatic and morphological characteristics. To confirm the species, the analysis of nucleotide sequences was carried out for the site of the internal transcribed spacer.

In order to develop PCR tests that allow identifying the phytopathogen Xanthomonas translucens, which is significant for the export of Russian grain products, a search was made for a suitable PCR target. As a result of bioinformatic analysis of annotated proteins corresponding to the coding sequences of 10 genomic assemblies of the target bacterium – Xanthomonas translucens – and 161 genomic assemblies of 25 other species of bacteria of the genus Xanthomonas, downloaded from NCBI GenBank in March 2020, 6 genome regions specific for Xanthomonas translucens and suitable for use as a PCR target. The nucleotide sequences of these genes were used to design primers. For the discovered sequences, 12 pairs of primers were developed – 1F8/1R8, 1F10/1R10, 2F6/2R6, 3F3/3R3, 3F5/3R5, 3F9/3R9, 4F1/4R1, 4F3/4R3, 5F3/5R3, 5F6/5R6, 6F6/6R6 and 6F10/6R10, the species-specificity of which was tested in the course of the study with 35 strains of bacteria of the genus Xanthomonas, including Xanthomonas translucens. Analysis of the results of the PCR performed and the alignment of the obtained nucleotide sequences of the PCR products using the BLAST algorithm based on the NCBI showed that the primer pairs 1F8/1R8, 1F10/1R10, 4F1/4R1, 5F6/5R6, and 6F10/6R10 are suitable for their use in the diagnosis of the pathogen causing bacterial leaf streak of wheat, Xanthomonas translucens. New PCR tests can become part of the solution to the problem of establishing the phytosanitary state of consignments of Russian grain products, and will also make it possible to inspect the territories of the Russian Federation and inspect consignments of regulated products.

The history of spreading of the invasive species Cyclachaena xanthiifolia (Nutt.) Fresen. (Iva xanthiifolia Nutt.) in some European countries and in the Russian Federation has been studied. The area of giant sumpweed in the Republic of Crimea and the Russian Federation in general has been analyzed, based on research data, herbarium samples and original field studies. The most typical plant communities, in which the species is regularly introduced, have been determined. The directions and volumes of grain products export have been considered, taking into account the phytosanitary requirements of importing countries. The phytosanitary significance of the species has been emphasized for a number of countries importing Russian grain products, which included giant sumpweed in their quarantine lists. Some data on phenology and peculiarities of ontogenetic development of the species in the conditions of the foothill Crimea and on the basis of the quarantine introduction area of the Southern Branch of FGBU “VNIIKR” in 2020 are presented. 

The work presents the results of field studies of 3 pheromone trap types produced by FGBU “VNIIKR” for collecting oriental fruit moth Grapholita molesta (Busck, 1916) in the conditions of the southern coast of Crimea. It was stated that the most efficient were the trap types “Delta” and “Diamond”, which could collect 158 and 156 individuals/trap respectively. At the same time, “Quadro” traps turned out to be less effective; the number of oriental fruit moth males collected were 104 individuals/trap.