Fungal diseases of plants are of great economic importance causing 70–80% of crop losses associated with microbial plant pathogens. Advanced on-site disease diagnostics is very important to maximize crop productivity. In this study, diagnostic systems have been developed for simultaneous detection and identification of six fungal pathogens using 48-well microarrays (micromatrices) for qPCR. All oligonucleotide sets were tested for their specificity using 59 strains of target and non-target species. Detection limit of the developed test systems varied from 0.6 to 43.5 pg of DNA depending on target species with reproducibility within 0.3−0.7% (standard deviation). Diagnostic efficiency of test systems with stabilized and freeze-dried PCR master-mixes did not significantly differ from that of freshly prepared microarrays, though detection limit increased. Validation of test systems on 30 field samples of potato plants showed perfect correspondence with the results of morphological identification of pathogens. Due to the simplicity of the analysis and the automated data interpretation, the developed microarrays have good potential for on-site use by technician-level personnel, as well as for high-throughput monitoring of fungal potato pathogens.

The effects of cyst components of the potato cyst nematode, Globodera rostochiensis, on in vitro hatching of juveniles were evaluated. Aqueous homogenates of eggs and cyst walls, and aqueous rinses of cyst walls and eggs were examined. Homogenates of cyst walls or rinsates of either cyst walls or eggs each significantly increased hatch of juveniles five-fold compared with sterile distilled water controls. Cyst or egg homogenates induced significant increases (7.7-9.0-fold) in hatch of juveniles compared with controls. These values represent approximately 24.8-29.0% of the 31-fold induction of hatch of juveniles by potato root diffusate, routinely used to stimulate hatch in G. rostochiensis. The hatch inducing factor(s) in cyst homogenates was thermostable and retained activity after repeated freezing and thawing. Filter fractionation of cyst homogenate localised activity between molecular mass 0.5 kDa and 5 kDa, with no hatch inducing activity present above 5 kDa. Apparent depression of hatch induction at high concentrations of non-fractionated cyst homogenates suggests the presence of hatch inhibitors.

Plesiotype specimens of the European dagger nematode, Xiphinema diversicaudatum, were collected in Saratov, Russia, and morphologically, morphometrically and molecularly characterised. PCR with specific primer was developed for rapid diagnostics of this species. Phylogenetic relationships of X. diversicaudatum with other Xiphinema species, as inferred from the analyses of the D2-D3 expansion segments of 28S rRNA, ITS rRNA and coxI mtDNA gene sequences, are also provided. The study revealed that the clade X. diversicaudatum, together with X. bakeri (North America) and X. chengi (Asia), is related to Xiphinema species from the Mediterranean region and likely originated from a common ancestor inhabiting this area. The phylogenetic reconstructions with coxI mtDNA were used to describe the pattern of present genetic diversity of X. diversicaudatum and infer its biogeographical history in Europe. Haplotype diversity of X. diversicaudatum populations from Central Europe was significantly higher than those from south-eastern Europe, central, south-eastern and southern European Russia. It has been hypothesised that, during the Last Glacial Maximum, X. diversicaudatum populations probably persisted in refuge areas in the Carpathian mountains or the Alps, the species subsequently expanding from these areas and colonising other regions in Europe.

Highly adapted obligate endoparasites of the root system, root-knot nematodes (Meloidogyne spp.), cause great damage to agricultural crops. Our research is aimed at the assessment of nematicidal activity and effectiveness of antagonist fungal and bacterial strains against the most common type of root-knot nematode in the south of Russia. By means of molecular genetic identification, it was found that in the south of Russia, the species Meloidogyne hapla Chitwood, 1949 and Meloidogyne incognita (Kofoid and White, 1919) Chitwood, 1949 cause galls on the roots of open-ground and greenhouse tomato. Screening of microbial agents against second-stage juvenile (J2) M. hapla was carried out in the laboratory. At the end of the experiment, two liquid fungal cultures of Paecilomyces lilacinus BK-6 and Metarhizium anisopliae BK-2 were isolated, the nematicidal activity of which reached 100.0 and 70.2%, and exceeded the values of the biological standard (Nemotafagin-Mikopro) by 38.4% and 8.8%. The highest biological efficacy was noted in the liquid cultures of P. lilacinus BK-6, M. anisopliae BK-2, and Arthrobotrys conoides BK-8 when introduced into the soil before planting tomato. The number of formed galls on the roots was lower in comparison with the control by 81.0%, 75.5%, and 74.4%.

Globodera rostochiensis is one of the 100 most dangerous invasive species in Russia, causing significant damage to agriculture. In Russia, this nematode was first founded in Kaliningrad Region in 1949. In this study, we used ensemble modeling (ESDM) methods to predict the potential distribution of G. rostochiensis in Russia and found that with changes in global climate and land use in the future, there would be a tendency to expand the range in two directions - from the south to the north and from the west to the east. The history of the distribution of the species on the territory of Russia, the current and potential ranges of the species from 2020 to 2100 with a step of 20 years in the implementation of various models and scenarios of climate change and land use are presented. Information on native range, features of biology, signs of host plant damage and injuriousness of G. rostochiensis , methods of pathotypes identification, invasion vectors, and control measures are shown. The predicted ranges of the species are important for the development of measures to minimize future invasion of G. rostochiensis and their negative consequences