Plant Protection News (Vestnik Zashchity Rasteniy)

Genetic protection of wheat from leaf and stem diseases in the Volga region – problems and prospects

O. А. Baranova — 2026-06-15

In the conditions of changing climate and emergence of new virulent pathotypes of pathogens, advanced breeding for resistance is of primary importance. Its strategy includes both studying the pathogen by virulence, tracking new pathotypes, migration routes, determining effective resistance genes; and analysis of resistance of varieties and lines, identification of known resistance genes, search for new genes and introduction of effective resistance genes into adapted germplasm. Wheat (Triticum spp.) is one of the most important grain crops for humans. In Russia, the main grain-producing regions are Western Siberia, Krasnodar Krai and, of course, the Volga region. Stem and leaf rust, powdery mildew and tan spot are dangerous diseases of wheat, common in the Volga region, causing crop losses and reducing grain quality. The causative agents of the diseases are basidiomycetes Puccinia graminis f. sp. tritici (stem rust), P. triticina (leaf rust) and ascomycete fungi – Pyrenophora tritici-repentis (Drechslera tritici-repentis) (tan spot) and Blumeria graminis f. sp. tritici (Erysiphe graminis) (powdery mildew). This review systematizes modern data on the harmfulness of these pathogens, the features of their biology and pathogenicity factors. Particular attention is paid to the analysis of world and Russian studies of the population structure of phytopathogens based on virulence and DNA markers. Data on the racial composition of the Volga region fungal populations, R-genes effective against them, and the resistance of wheat varieties approved for cultivation in the Volga region are presented. The article summarizes information on the genetics of resistance of bread wheat to the diseases under consideration, including a description of known resistance genes and their sources. The problems and prospects of using these genes in breeding programs to create resistant varieties are considered.

Genetic potential of wild tomato relatives for resistance breeding in Solanum lycopersicum

A. V. Vishnyakova — 2026-06-15

The tomato Solanum lycopersicum ranks among the top three most produced vegetables worldwide, yet it remains vulnerable to various diseases, pests and abiotic stresses. Climate change exacerbates disease severity and abiotic impacts, increasing the demand for adaptive varieties and hybrids. Interspecific hybridization expands genetic diversity via introgression of target trait genes, potentially reducing reliance on chemical protectants, enhancing plant adaptive potential and improving abiotic stress tolerance. Recent studies focus on wild Solanum species as a source of valuable traits for tomato breeding. This review addresses the reproductive barriers between cultivated and wild species, which are of critical significance for plant breeding and examines the methodologies developed to overcome these barriers. Currently, wild species are most actively involved in breeding programs and in the introgression of traits into the cultivated tomato include S. cheesmaniae, S. habrochaites, S. pennellii, S. pimpinellifolium. Species S. peruvianum, S. chmielewskii, S. corneliomulleri, S. sitiens, S. ochranthum, S. lycopersicoides, S. sisybrifolium are difficult to hybridize with cultivated tomato, and have not yet contributed substantially to the introgression of valuable traits. The success of interspecific hybridization with wild relatives largely depends on the choice of compatible tomato genotypes, the utilization of cultivated tomato as the maternal parent, and the application of embryo culture techniques to rescue hybrids in cases of embryo abortion. Somatic hybridization offers an alternative approach for overcoming interspecific crossing barriers. However, its effectiveness in facilitating the introgression of desirable traits into tomato remains insufficiently evaluated.

Endophytic colonization of plants by the fungus Akanthomyces muscarius and its effect on the peach aphid Myzus persicae

G. V. Mitina — 2026-06-15

The ability of three strains of entomopathogenic fungus Akanthomyces muscarius to endophytic colonization was studied in beans, tomato and acanthus. In beans, phytoregulatory activity of the fungus was revealed. Watering soil with spore suspensions of strains Vl 21 and Vl 61 resulted in increase of green mass, plant length, and root mass (for Vl 61). Strain G-033 VIZR colonized beans most effectively when sprayed on leaves, occurrence in leaves and stems was 66 % and 40 %, respectively. Occurrence of Vl 61 in leaves and stems was 11–16 %. It was also found in roots and leaves after seed soaking in spore suspension, unlike other strains, which only colonized stems. The occurrence of Vl 21 was highest in leaves when sprayed (15 %). Colonization of beans with A. muscarius negatively influenced aphids feeding on these plants. On Vl 21-colonized plants, aphid fecundity was 26 % lower than in control and mortality reached 19 %. Vl 61 showed a fecundity decreasing trend and 50 % mortality of aphids. Strain G-033 VIZR didn’t affect aphid fecundity but caused 57 % mortality. Occasional aphid specimens displayed cases of mycoses. When the soil under tomato plants was watered with fungal spore suspension, the isolates predominately colonized the tomato stems, while colonization rate of leaves and roots did not exceed 8 %. The ability of green fluorescent protein-labeled strains Vl 61* and Vl 72* to colonize perennial acanthus plants was shown. Both strains were isolated from all parts of the acanthus, most frequently from leaves and stems.

Molecular genetic analysis of new natural isolates of Lecanicillium-like fungi and study of their pathogenic properties

M. A. Cherepanova — 2026-06-15

The widespread use of chemical insecticides in agriculture is associated with numerous adverse effects, which substantiates the necessity of biological plant protection development. Entomopathogenic fungi are considered as promising biocontrol agents against arthropod pests. This study aimed to isolate and characterize new natural isolates of Lecanicillium-like fungi discovered in Russia and to evaluate their virulence against two dangerous sucking pests: the peach aphid Myzus persicae and the greenhouse whitefly Trialeurodes vaporariorum. Thirty isolates collected from various regions of Russia in 2019–2022 were identified using molecular genetic methods targeting the ITS, TEF, and NAD1 loci. The isolates were identified as Akanthomyces lecanii, A. muscarius, A. attenuatus, A. uredinophilus, Flavocillium bifurcatum, and Simplicillium lanosoniveum. Flavocillium bifurcatum being recorded in Russia for the first time. Laboratory bioassays revealed high variability in isolate virulence. Twenty two isolates demonstrated over 90 % biological efficacy on the 7 day against M. persicae, among them 16 isolates achieved 100 % efficacy. From 22 tested isolates 15 showed over 80 % efficacy towards T. vaporariorum. The most promising isolates belong to the species A. uredinophilus, A. muscarius, A. attenuatus, and F. bifurcatum. The latter was tested against both target pests for the first time. Consequently, 15 highly virulent isolates were selected as promising agents for the control of aphids and whiteflies.

Toxicity of neonicotinoids to phytoseiid mites (Mesostigmata, Phytoseiidae)

O. V. Babkina — 2026-06-15

The study aimed to evaluate the possibility of the combined use of phytoseiid mites and neonicotinoids in agricultural production. To answer this question, laboratory tests were performed. The research objects were the polyphagous phytoseiid species Neoseiulus californicus and N. agrestis, which are widely used for the protection of vegetable and ornamental crops in greenhouses. Laboratory experiments showed that treatment with the neonicotinoids Actara and Confidor at recommended field concentrations had no negative effect on the longevity or fecundity of adult mites. However, when treatments were applied to juvenile developmental stages, high contact toxicity of the preparations was observed, especially toward protonymphs, whose mortality reached 70 %. For larvae and nymphs, this показатель averaged 30–40 %. When treatment was applied at the egg stage, viability of the tested phytoseiids remained at the control level. The obtained results will serve as a methodological basis for optimizing the combined use of phytoseiids and neonicotinoids in integrated pest management systems in greenhouses.

Genotyping of strawberry varieties for loci of resistance to anthracnose (Colletotrichum spp.)

A. S. Lyzhin — 2026-06-15

Molecular marking of 54 strawberry varieties (Fragaria × ananassa) for resistance loci to Colletotrichum acutatum (FaRca1, Rca2) and C. gloeosporioides(FaRCg1) was carried out. At least one of the studied resistance loci is present in 73.7 % of the analyzed strawberry varieties. Resistance alleles to C. acutatum of the pathogenicity group 1 (FaRca1) and the pathogenicity group 2 (Rca2) were detected in 40.3 % and 12.3 % of the analyzed varieties. All identified varieties – carriers of the FaRca1 and Rca2 alleles have a heterozygous genotype. The FaRCg1 resistance locus to C. gloeosporioides is present in 40.3 % of samples. A statistically significant predominance of the FaRCg1 locus was noted in Russian strawberry varieties. The identified varieties – carriers of the FaRCg1 allele can have a homozygous or heterozygous genotype. Two loci out of three in three variants of the combination of resistance alleles (FaRca1+FaRCg1, FaRca1+Rca2, FaRCg1+Rca2) were detected in 15.8 % of samples, and in most cases (77.8 %) this is a combination of the FaRca1 and FaRCg1 loci. Among Russian strawberry samples, this allelic combination has been identified in the varieties Zenit, Neznakomka, Urozhaynaya TSGL, and Flora; among foreign samples – in the varieties Korona, Salsa, and Vicoda. The combinations FaRca1+Rca2 and FaRCg1+Rca2 characterize the varieties Aprica and Sudarushka, respectively. Three resistance alleles were identified in the strawberry variety Borovitskaya (1.7 % of the total number of samples). The indicated strawberry varieties are promising complex genetic sources of alleles of resistance to anthracnose caused by C. acutatum and C. gloeosporioides.

Оценка применимости конвейера обработки гиперспектральных данных, разработанного для ранней диагностики ржавчинных заболеваний зерновых, для фенотипирования пшеницы, ржи и ячменя

D. V. Kuznetsova — 2026-06-15

Hyperspectral sensing data processing pipeline, originally developed for the early diagnosis of rust diseases in grain crops, was assessed for its applicability for the task of phenotyping of healthy plants of wheat Triticum aestivum, barley Hordeum vulgare, and rye Secale cereale. Hyperspectral images of healthy plants, obtained under laboratory conditions using a Cubert Ultris 20 camera (450–874 nm range, 106 channels), were utilized. The effectiveness of various preprocessing schemes was compared: full (including normalization, smoothing, calculation of derivatives, and identification of extreme features), reduced, and minimal. Machine learning models were exploited for classification: logistic regression, support vector machine, and gradient boosting, trained on averaged spectra. It is shown that the use of a full pipeline optimized for phytopathological diagnostics leads to reduced classification accuracy in phenotyping tasks. The best results (F1 = 0.97 ± 0.025) were achieved using the original averaged spectral curves without additional transformations. It is concluded that for healthy wheat, barley, and rye phenotyping, absolute reflectance levels are informative, whereas for disease diagnostics, changes in the shape of the spectral curve are more important. The obtained results clarify the applicability limits of pipelines developed for phytosanitary purposes and can inform the development of remote monitoring and phenotyping systems for cereal crops.

Infection and long-term cultivation of the microsporidium Nosema bombycis in Sf9 insect cell culture

I. V. Senderskiy — 2026-06-15

The microsporidium Nosema bombycis is economically important as a causative agent of silkworm pebrine, and also as a potential biological control agent for lepidopteran pests such as Dendrolimus sibiricus. In this study, N. bombycis spores were isolated from diseased Bombyx mori larvae. After artificial stimulation in 0.1 M KOH, they were inoculated into the Sf9 cell line to initiate continuous proliferation of the parasite. After 7 days of initial infection, fresh Sf9 cells were added, establishing a long-term persistently infected culture. We quantified the percentage of infected cells and the dynamics of spore accumulation during primary infection and long-term cultivation, and determined the limits of cell survival and infectivity in the infected culture. Our studies enabled us to propose key parameters for utilizing this host-parasite system as a model for studying nosematosis and resistance mechanisms, as well as for the mass-production of spores for plant protection.

Monitoring of the citrus greening disease (Huanglongbing) in relation to environmental factors in Pakistan

S. Bashir — 2026-06-15

The environment plays a crucial role in disease development and their outbreaks. Understanding the pattern of disease progression requires close examination of environmental factors, which are strongly associated with disease severity. This study aimed to investigate the relationship between severity of the citrus greening disease, also known as Huanglongbing, and ecological variables specifically maximum and minimum temperatures, rainfall, and relative humidity using correlation and regression analysis. The analysis showed a significant correlation between the disease severity and these environmental factors. Correlation and regression equations were employed to develop a predictive model for disease progression. Results indicated that environmental conditions significantly influenced symptom expression, contributing to disease severity. The coefficient of determination (R²) values in regard to temperature dependence for the three citrus varieties i.e. Kinnow, Feutrell’s Early, and Mosambi were 75 %, 82 %, and 83 %, respectively. These findings confirm that environmental factors play a substantial role in the progression of Huanglongbing. The developed model can be applied to guide effective disease management strategies.

Information on the distribution of the four-eyed fir bark beetle Polygraphus proximus in the plantings of the Sverdlovsk region, based on the results of surveys in 2025

V. I. Ponomarev — 2026-06-15

The spread of the dangerous pest of coniferous plants, the four-eyed fir bark beetle Polygraphus proximus, beyond its historical range, poses a serious threat to fir plantations in the regions of invasion. This research provides information on the distribution of the species in the Sverdlovsk Province based on the results of surveys conducted in 2025. The increase in the number of locations where the four-eyed fir bark beetle was found indicates that the species has successfully adapted almost to the entire territory of the Sverdlovsk Province. Currently, the main foci are concentrated in the south-west of the region. The research results indicate that since the discovery of the invader in the Sverdlovsk region in 2023, the increase in the area of foci with the death of fir plantations has been very intense.