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The APETALA 2/ethylene response factors (AP2/ERFs) are considered essential in plant disease resistance responses. In this study, a novel eggplant AP2/ERF transcription factor gene, StPti5, was identified and functionally described from wild eggplant (Solanum torvum Sw.). The results of bioinformatics analysis show that StPti5 protein contains a DNA-binding AP2/ERF domain and shares high degree of amino acid similarity with the other known AP2/ERF domain. Subcellular localization assay shows that StPti5 protein was localized in the nucleus. Expression of StPti5 was induced by infection with Verticillium dahliae, ethylene, and methyl jasmonate. Analysis of expression patterns suggests that the function of StPti5 in resistance to Verticillium wilt was most closely linked to ethylene signaling. Overexpression of StPti5 in Arabidopsis thaliana could improve disease resistance to V. dahliae and activate genes linked to the ethylene signaling pathway. Studies on the A. thaliana defence response revealed that the formation of reactive oxygen species (ROS) increased considerably following overexpression of StPti5. In summary, our analysis suggest that StPti5 gene is a functional gene that could improve eggplant's resistance to V. dahliae.

SNF1-related protein kinase (SnRK2) is a critical positive regulatory factor in the abscisic acid (ABA) signalling pathway. However, the roles of the HbSnRK2 gene family members in the rubber tree, especially in response to stress, have not been thoroughly characterised. Here, we cloned six HbSnRK2 genes from the rubber tree. Based on the phylogenetic analysis, the HbSnRK2 family genes were divided into three groups. The motifs and intron numbers of HbSnRK2 were conserved. Analysis of cis-regulatory element sequences of all HbSnRK2 genes identified ABRE and TC-rich elements in the prompter of all the HbSnRK2 genes, illustrating that HbSnRK2 could be adjusted by the ABA and stress responsiveness. The qRT-PCR analysis showed that the expression patterns of the six HbSnRK2 genes differed in different tissues. The expression of these genes also differed under treatment with the plant hormone ABA, the HbSnRK2.2 gene was especially significantly expressed under the ABA treatment. Moreover, the HbSnRK2.2 gene responded to glyphosate, powdery mildew, heat stress and cold stress processes, which indicates that the HbSnRK2.2 gene plays an important role in phytohormone signalling and stress response in rubber trees. Taken together, the study provides valuable information to further define the role of the HbSnRK2 gene in rubber trees.

Steinernema glaseri is a potential biocontrol agent against white grubs of the Phyllophaga spp. complex; however, its suitability for in vitro multiplication has been scarcely investigated. In this study, the effects of the surface culture of NJ-43 strain with its symbiotic bacteria Xenorhabdus poinarii on egg-yolk agar (P2), chicken-liver agar and nutrient meat-peptone (MP) agar on infective juvenile (IJ) productivity and their virulence against Galleria mellonella larvae were investigated. The bacteria on the surface of the agar were first incubated in darkness at 30 °C for 54–102 h, and then 100 surface-sterilised IJs were added. After two harvests, the accumulated productivity was higher on chicken-liver agar (536 × 103 IJs/m2 day) and P2 agar (534 × 103 IJs/m2 day) than on nutrient MP agar (58 × 103 IJs/m2 day). The mean virulence of the in vitro produced IJs was 46–60% and showed no statistically significant difference among the three culture media. In conclusion, the maximum multiplication factor of S. glaseri NJ-43 on solid media was 385, and its original virulence was retained.

Turnip mosaic virus (TuMV) is the most important virus of brassica crops. In our study, we compare the genetic structure of two Czech TuMV populations sampled in the country's 25-year interval of virus presence. The 21 isolates, mainly infecting rutabaga and horseradish, were collected from four farms under organic production, and nearly complete genome sequences, 9 596–9 787 nt in length, were obtained using Sanger sequencing for all of them. The analysis of variability and polymorphism showed differences in genetic structure but the relative stability of both populations and moderate negative selection as a factor affecting the current TuMV population. The newly collected isolates are characterised by a relatively high frequency of intralineage recombinants; interlineage recombinants were not detected compared to the 25-year-old population. The phylogenetic analysis allowed the classification of all Czech isolates into world-B phylogroup, with the prevalence of isolates of subgroup B2. The spread of isolates belonging to the other phylogenetic groups posing higher phytopathological risk, which were present in the old population and some surrounding countries, was not found.

The study was carried out in the agricultural landscape (mosaic of an urban environment, gardens, grassland, fields, small forests and semi-natural non-forest habitats) in central Europe (southeast Czechia) in 2021. A light trap was used for trapping (207 nights). A total of 485 moth species and 5 170 individuals were captured. Eurytopic species dominated the area, 72% of species and 89% of individuals. Fifty-nine species are considered pests (12%), representing 25% of individuals. The seasonal dynamics of selected harmful species were evaluated and discussed. Species of semi-natural dry and wet habitats were represented by 14%, i.e. a proportion comparable to pests, but with only 4% of individuals. The numbers of species and individuals recorded and the Shannon-Wiener diversity and evenness indices are lower than at natural sites. Yet, overall biodiversity is relatively high, including the presence of some rare, ecologically, or zoogeographically remarkable species.

Mungbean seeds [Vigna radiata (L.)] are easily damaged by insects during storage, and essential oils (EOs) have proved effective for controlling insect infestation. This research study assessed the bioactivity of EO from Jasminum sambac (L.) Aiton against Callosobruchus maculatus (F.). The chemical composition of EO was analysed by a gas chromatograph-mass spectrometer (GC-MS). All experiments were conducted following a completely randomised design (CRD) with four replications of the residual contact and seed dressing bioassays. Results indicated that J. sambac EO contained 35 compounds (97.587%), with the main component 3-hexen-1-ol benzoate. Residual contact toxicity LC50 values of this EO on adult C. maculatus at 24, 48, and 72 h were 5.01, 4.00, and 3.13 µL/mL, respectively. J. sambac EO at 8 µL/L showed the highest residual contact efficacy against C. maculatus, killing up to 100% in 72 hours. The highest concentration of J. sambac EO (1 mL/kg) gave optimal protection against C. maculatus within 4 and 5 days with 100% mortality. This concentration showed 100% inhibition of adult F1 progeny emergence, with no seed damage and weight loss of V. radiata L. after 30 days of exposure, and not significantly different from 0.8 mL/kg. Results indicated that J. sambac EO effectively prevented C. maculatus infestation and it could be used as an alternative to commercial chemical insecticides.

Sisal purple leafroll disease (SPLD) is a destructive disease affecting sisal in China, however, its etiology remains unknown. This disease is characterized by purple margins and rolling and yellowing of the leaves. Recently, phytoplasma was found to be present in SPLD-affected sisal according to PCR assay. To further verify the presence of phytoplasma, determine its association with SPLD and identify the possible pathogenic phytoplasma infecting sisal, 80 symptomatic and 65 asymptomatic sisal samples were collected from the main sisal farms in three Chinese provinces, including Hainan, Guangdong and Guangxi provinces, from 2018 to 2021. PCR assays and transmission electron microscopy further revealed the presence of phytoplasma. Nested PCR using the universal primer R16mF2/R16mR1 followed by R16F2n/R16R2 was confirmed as the most effective molecular method for the detection of phytoplasma in sisal. A comparison of the detection rate of phytoplasma in symptomatic (83%) versus asymptomatic (17%) sisal populations showed some association between phytoplasma and SPLD. Sequencing analyses, phylogenetic analyses, and virtual restriction fragment length polymorphism analyses confirmed the presence of phytoplasma in sisal belonging to 16SrI-B. This is the first report of 16SrI-B phytoplasma infecting sisal in China.

Due to the length of egg-laying period (> 80 days), two applications of insecticides against cabbage stem weevil (Ceutorhynchus pallidactylus Marsh.) are currently needed. However, resistance of pollen beetle (Brassicogethes aeneus F.) to pyrethroids complicates the choice of suitable insecticide for the second application. The active ingredients cypermethrin, etofenprox, pymetrozine, indoxacarb and chlorpyrifos-ethyl applied as second spring applications to winter oilseed rape crops were assessed under field conditions from 2016 to 2018 to ascertain how they could reinforce the effects of the first spring application (beta-cyfluthrin) on cabbage stem weevil. Chlorpyrifos-ethyl and etofenprox strengthened the effects of the first spring spray on cabbage stem weevil markedly more than cypermethrin. Pymetrozine and indoxacarb, effective on resistant populations of pollen beetles, showed the lowest contribution to increase the effects. Indoxacarb showed a low effect on C. pallidactylus in laboratory tests too. The impacts of the bans on active ingredients chlorpyrifos-ethyl and pymetrozine are discussed.

The leucine-rich repeat receptor-like kinases (LRR-RLKs) compose a large gene family in plant genomes and implement essential functions in diverse plant physiology progress, including defence against pathogens. However, a systematic analysis of LRR-RLKs has not been accomplished in the economically important cucumber. 189 LRR-RLK genes were identified in the cucumber genome and further divided into 22 subgroups based on the sequence similarities in this study. A total of 31 segmental duplication events and 15 tandem duplication events were present in the genome, indicating that the two duplications were the main driving forces for the expansion of the LRR-RLK family in the cucumber. The expression profile analysis revealed that most of the CsLRR-RLKs were upregulated during a downy mildew infection, and resistant cucumbers comprised more upregulated CsLRR-RLKs than the sensitive lines. Taken together, our results provided information on the LRR-RLK gene family in the cucumber and contributed valuable information for the further research of CsLRR-RLKs.

Symptomatic samples were taken from five districts in Yogyakarta and Central Java provinces of Indonesia to survey the genetic diversity of Begomovirus, α and β satellites. A total of 14 samples were tested positive by PCR for tomato leaf curl New Delhi virus (ToLCNDV), pepper yellow leaf curl Indonesia virus (PepYLCIV), mungbean yellow mosaic India virus (MYMIV), and ageratum yellow vein China virus (AYVCNV) infections. Besides that, ageratum yellow vein alphasatellite (AYVA) was identified for the first time in Indonesia, and tomato leaf curl Java betasatellite (ToLCJaB) were detected for the first time in different hosts. Partial genome sequences of begomoviruses and complete sequences of the α and β satellites were recovered and registered in NCBI GenBank (OP846592-OP846615). Phylogenetic study showed that AYVA and ToLCJaB each had two separate lineages. Polymorphism and diversity analyses confirmed other reports that βC1 coding region of ToLCJaB genome is highly conserved. Comparison of phylogroups 1 and 2 of ToLCJaB produced a high FST value, indicated genetic isolation between them. This report could be a basis for future works on the less studied genetic variation of α and β satellites in Indonesia and other countries.

New techniques for Ceratitis capitata (Wiedemann, 1824) control are being studied and developed to replace traditional organophosphate pesticide applications. A mass trapping strategy offers promising medfly control within integrated pest management (IPM) programmes. Field assays were performed to study the efficacy of two mass trapping techniques based on PheroNorm^® and Ceratrap^® lures that were compared to a conventional approach to control the medfly in Tunisian apricot orchards. The results showed that both mass trapping techniques had a similar efficiency in reducing the C. capitata population. The degrees Brix in the fruits was a determinant issue since the initial apricot fruit damage was detected at 6.4%. At harvesting, the lowest fruit damage rate was recorded in the PheroNorm^® (4.25%) and Ceratrap^® (6.50%) treated orchards, compared with the conventional approach (10.75%). Therefore, the use of 50 PheroNorm^® and Ceratrap^® traps per ha density within an IPM approach may be very useful to control the C. capitata populations in apricot orchards.

This study aimed to isolate and characterise the pathogen associated with Alternaria leaf spot on broccoli and to evaluate the inhibitory effects of fungicides against it. We isolated and identified the fungal pathogen as Alternaria sp. using morphological and cultural methods. Based on the aligned sequences of the internal transcribed spacer (ITS) and molecular phylogenetic analysis by the neighbour-joining method, the isolates (Ab1 and Ab2) were confirmed as Alternaria alternata. The conidia of the isolates were dark brown, cylindrical, obclavate to muriform. The conidiophores were olivaceous brown, septate, and branched. The conidial morphology of the isolates ranged from 52.4-92.4 × 10-20 μm with 2-6 transverse and 0-3 longitudinal septa. Both isolates yielded positive results in the pathogenicity test on broccoli leaves by developing brown and circular spots with concentric rings on the leaves surrounded by yellow halos. The culture studies revealed that the maximum growth of the pathogen was obtained at 30 °C and pH 6.0. Tilt 250 WC showed the highest potential in suppressing the mycelial growth of the A. alternata in vitro at a concentration as low as 50 µg/mL. The results from this study contributed to the positive identification of the pathogen and characterised A. alternata as a destructive pathogen of broccoli which may be successfully controlled by the fungicide Tilt.

Invertebrate seed predation is a potential ecosystem service that substantially reduces weed seeds in crop fields, decreasing the seedling emergence and, thus, limiting the weed competition next season. It may, thus, be considered as a natural component of the long-term weed management toolbox. This study aimed to measure the post-dispersal invertebrate seed predation levels of the following relevant weed species in Hungarian maize fields: Ambrosia artemisiifolia, Datura stramonium, Chenopodium album, and Echinochloa crus-galli, and to compare the predation levels among them. We hypothesised that invertebrate seed predators will predate weed seeds, but the predation levels may vary with the weed species. Two sampling rounds were performed, in November 2019 and October 2020, in Gödöllő, Hungary. A total of 100 seed cards/round were placed on the soil surface inside a maize field prior to harvest, 10 m from the field's edge, along 25 transects, with four cards/transect. A distance of 10 m was set between the transects and 1 m between the cards. Twenty seeds of each weed species were glued onto sandpaper (25 × 10 cm, P-60), and a wire mesh was used to exclude vertebrate predators. The seed removal was calculated every 24 h, for seven days in 2019 and for five days in 2020, and then the seed predation was measured using the number of removed seeds on each card. The results showed high seed predation levels on all the seed cards, with an overall average of 85.9 ± 13.7%. Besides, there was a decrease in the % of remaining seeds on the cards starting from the first day after exposure due to seed predation in both years. The optimum exposure period for measuring the seed predation was found to be three to four days, though the number of predated seeds on days 3 and 4 significantly differed between years (P < 0.001), with higher predation rates in 2020 than in 2019. However, no differences were detected in the predation rates among the weed species (P = 0.962, 0.079). These findings indicate the potential contribution of seed predation by invertebrates to weed management in Hungarian maize fields.

Current efforts are focused on the search for efficient methods of pathogen management that will not result in damage to the environment or cause an imbalance in the existing biota. One of the strategies for this is the use of nanoparticles in agriculture for disease management. This review presents a summative view on the various applications of nanoparticles in conferring disease resistance to crops and the possibility of using nanoparticles as carriers of genetic material for the generation of disease resistant crops. Nanoparticles are directly being used for the control of pathogens. Nanoparticles have been used as antiviral, antifungal and antibacterial agents. The nano-encapsulation of pesticides in controlled release matrices is one of the most promising research areas for the future. Nano-encapsulation has been shown to increase the efficiency of pesticides, reduce their volatilisation and decrease the toxicity and environmental contamination in crops. Nano-encapsulated agrochemicals or biomolecules can be engineered to be released in a controlled manner and in a target-specific location. Nanoparticles also have great scope in the field of transgenics vis-à-vis pathogen resistance. The field of agriculture can be revolutionised by the use of nanoparticles for imparting disease resistance in crops. The field is so versatile that the possibilities are endless.

Bacterial antagonists are effective as an alternative to synthetic bactericides in the control of potato soft rot. The use of bioagents reduces the application of synthetic bactericides, which are harmful to humans and the environment. However, the mechanisms of some bioagents, such as some fungi and bacteria, are not yet understood. This paper reviews the current situation of potato soft rot, biological controls, antagonistic bioagents and their mechanisms, application strategies and future directions in today's agriculture. These mechanisms include mycoparasitism, competition, rhizosphere colonisation, synthesis and release of metabolites. Bioagents increased the defensive system of plants by increasing the antioxidants genes, such as superoxide dismutase, peroxidase (POD) and catalase (CAT), and eventually increased the plant growth and yield production.

Identifiable endophytic bacteria with plant growth-promoting traits promise to ensure sustainable agriculture. However, information on the versatility and exploration of sunflower-associated bacteria as bioinoculants is less studied. Here, we present the whole-genome sequence and annotation of Stenotrophomonas maltophilia JVB5 isolated from the sunflower root endosphere from the North West province, South Africa. The whole-genome analysis revealed a genome size of 4 771 305 bp, a sequence read count of 8 764 890, a 66% guanine-cytosine content, 57 tRNAs, 268 contigs, and 4 160 protein-coding genes with functions in various metabolic pathways. Pathways involved in the indole acetic acid production were found in the S. maltophilia JVB5 genome. The whole-genome annotation predicted notable genes involved in bacterial colonisation, antibiosis, and plant growth promotion. The predicted genes are involved in the sulfur metabolism, and the oxidative stress may enhance the plant growth promotion and boost plant the resistance to stress. Upon inoculation, S. maltophilia JVB5 efficiently colonised the sunflower root under greenhouse conditions with a significant improvement on the wet plant weight of 437.20 g compared to the uninoculated control with a 331.04 g wet weight. The genomic analysis revealing specific functional genes in the bacteria genome suggests their bioprospecting in agriculture. Hence, understanding the mechanisms employed by S. maltophilia JVB5 based on the predicted multifunctional genes will help harness their bioresource in sustainable plant health.

The ability of Burkholderia GanoEB2 formulated in two different bioorganic powders as carriers - bioorganic empty fruit bunch (BEFB) and real strong bioorganic fertilizer (RSBF), and the efficacies of Burkholderia GanoEB2 in suppressing Ganoderma boninense infection in oil palm seedlings were determined. Results showed that the highest reduction in disease incidence (DI, 18.2%), severity of foliar symptoms (SFS, 26.6%), and disease severity foliar index (DSFI, 27.7%) was achieved by the seedlings treated with RSBF containing Burkholderia GanoEB2 compared to the seedlings treated with BEFB containing Burkholderia GanoEB2 (36.4% DI, 33.4% SFS, and 31.8% DSFI). Untreated seedlings (as control) had 100.0% DI, 90.4% SFS, and 87.5% DSFI. The disease was reduced by as much as 85.3% for seedlings treated with RSBF and by 70.5% for seedlings treated with BEFB. The formulated bioorganics containing Burkholderia GanoEB2 were proven to suppress Ganoderma disease in oil palm.

The cypress jewel beetle Lamprodila (Palmar) festiva is a wood-boring pest posing a major threat to the phytosanitary conditions of several coniferous trees. Its unprecedented European expansion has triggered serious plant protection concerns in several new habitats. Parts of Chamaecyparis lawsoniana injured by L. festiva were collected and analysed by computed tomography in order to study the dimensions of the cavities caused by L. festiva larvae as well as the larval positions. It is concluded that computer tomography representing a non-invasive approach is a promising tool for the visual depiction of the position and the physical parameters of the cavities formed. According to our experimental data, the penetration into the cypress caused by larvae and, inherently, its depth depends on the diameter of the branch. Additionally, the developing larvae appeared to keep distance from each other, which also depended on the diameter of the attacked branch. Our approach provides new data to the biological traits of the species. The main benefit that our imaging method furnishes is the exact, stress-free measurement method of the hidden developing stages. Its additional advantage is the indirect pest identification, which is based on the predetermined pest-specific damage characters.

The in vitro compatibility of the entomopathogenic fungus, Cladosporium cladosporioides BOU1, with the crude extract of three plants viz. Calotropis gigantea, Vitex negundo and Carissa macrocarpa at a concentration of 1% and 2% was investigated. The compatibility of the fungal isolate with the plant extracts was calculated using the biological index formula from the germination percentage, radial growth and spore production of BOU1. The compatibility of the plant extracts with the fungal isolate was also assessed based on the protease and lipase activities of the treated fungus. Both concentrations of plant extracts did not significantly inhibit the germination percentage, radial growth and spore production of BOU1 in a dose-depended manner. The average mean values of the biological index for the three plant extracts with two concentrations were more than 98%. The analyses of the data with the compatibility index formula suggest that irrespective of concentration, all three plant extracts were compatible with BOU1. When the plant extracts were added to the fungal isolate, the protease and lipase activities of the fungal isolate were not significantly inhibited compared to the untreated control. The reduction in all the variables of fungal growth and the enzymatic activity was less than 10% and 20%, respectively. From these findings, we can conclude that the fungal biocontrol agent C. cladosporioides BOU1 is compatible with the investigated plant extracts in terms of the fungal growth and enzymatic activities.

Phytoplasma-like symptoms of leaf yellowing and calyx malformation were observed in eggplant (Solanum melongena L.), upward leaves and fruit malformation in pepper (Capsicum annuum L.), and aerial tuber formation in potato (S. tuberosum L.) during the survey performed in the late season (August to September) of 2015 and 2016 in Van province (Turkey). A total of 100 samples were tested by nested-PCR using universal primer pairs to assess the sanitary status of the solanaceous crops and to characterise the phytoplasma isolates. Among them, seven samples resulted in a 1.25 kb DNA fragment, and five (two eggplants, two peppers, and one potato) were molecularly characterised (Accession No.: KY579357, KT595210, MF564267, MF564266, and MH683601). BLAST and the virtual restriction fragment length polymorphism (RFLP) analysis of 16S rRNA genes revealed the presence of two distinct phytoplasma infections in solanaceous crops: 'Candidatus Phytoplasma trifolii' a member of the clover proliferation group (16SrVI) and subgroup A and 'Candidatus P. solani' a member of the stolbur group (16SrXII) and subgroup A. The virtual RFLP analysis and calculated coefficients of RFLP pattern similarities further revealed a remarkable genetic diversity among the 'Candidatus P. solani' isolates infecting pepper (similarity coefficient of 0.90) and eggplant (similarity coefficients of 0.98 and 1.00) at the same geographical area. This is the first report of the natural occurrence of 'Candidadtus P. trifolii' in potato from the Eastern Anatolia region, Turkey.

The pear psyllid [Cacopsylla pyri (L.), (Hemiptera: Psyllidae)] represents one of the most economically significant pests of pear in Serbia and worldwide. It causes direct damage throughout feeding on young stems and leaves, but also creates favourable conditions for the development of plant diseases. In this article susceptibility of C. pyri to spirodiclofen, spirotetramat, and their combinations with foliar fertilizer (carboxymethyl cellulose-boron, CMC-B) was investigated in order to assess their efficacy. Experiments were conducted in accordance with standard OEPP/EPPO methods, in field trials on two localities in the Republic of Serbia (Kula, Vrbas), during 2020/21. Results of the field trials indicate good efficacy for all variants in pear psyllid control in pear orchards. The high efficacy of spirodiclofen (87.4-95.4%), spirotetramat (82.5-91.8%), spirodiclofen + CMC-B (90.3-99.8%), spirotetramat + CMC-B (89.5-96.8%) was achieved at both localities seven days after treatment during 2020/21 field trials. Also, it can be concluded for examinations 14 days after treatment, where the efficacy of spirodiclofen (84.9-92.0%), spirotetramat (81.2-91.7%), spirodiclofen + CMC-B (88.9-97.5%), and spirotetramat + CMC-B (82.3-92.5%) was high at both of investigated localities. Based on the obtained results it can be concluded that the high efficacy of the researched insecticides is a good indicator of C. pyri susceptibility in pear orchards.

Metabolites of Emericella nidulans (EN) were separated by chromatographic methods from crude hexane included emericellin and sterigmatocystin, while crude ethyl acetate found demethylsterigmatocystin. These metabolites proved to be antagonistic to Magnaporthe oryzae, the causal agent of rice blast. Crude extracts and nano-particles derived from EN inhibited M. oryzae. The ethyl acetate crude extract derived inhibited M. oryzae with an effective dose (ED₅₀) of 66 μg/mL. The nanoparticles showed better inhibition of M. oryzae than crude extracts at low concentrations. Nanoparticles, namely from crude ethyl acetate, crude methanol and crude hexane of EN were active against M. oryzae with ED₅₀ of 4.2 μg/mL, 4.5 μg/mL, 8.9 μg/mL, respectively. It detected sakuranetin (rate of flow value is 0.09) in nano-EN treated rice leaves. These nanoparticles inhibited M. oryzae and acted as a new elicitor to induce immunity.

The brown marmorated stink bug, Halyomorpha halys Stål, 1855 (Hemiptera: Heteroptera: Pentatomidae), is recorded from Slovakia for the first time based on a 5^th instar larva collected in the town of Štúrovo, Slovakia. The current distribution, economic importance and biology of the species are briefly reviewed. During the visit to Štúrovo, a mass occurrence of adults and larvae of the southern green stink bug, Nezara viridula (Linnaeus, 1758) (Pentatomidae), so far captured in Slovakia in 2014 only as a single specimen, was also observed. This observation confirms the presence of N. viridula as an established species in southern Slovakia. Both species are important pests to a large number of crops (vegetables, fruit trees, decorative plants, etc.) and can cause considerable economic losses.

Cryphalus asperatus (Coleoptera: Curculionidae, Scolytinae) is described as an exceptional but important secondary pest of Norway spruce seedlings. Of the 10 000 seedlings transported to one location in the Ore Mountains, Central Europe in 2020, in total 1 500 seedlings were killed by C. asperatus. The infestation and death of seedlings probably resulted in part from the substantial local increase in the local abundance of C. asperatus after the sanitation felling of many Ips typographus-infested and otherwise damaged trees; the felled trees provided many branches suitable for C. asperatus feeding. In addition, the seedlings were probably stressed by the multi-hour transportation (probably drought) from the forest nursery.

This study was conducted to examine the epidemiological characteristics of two Pseudomonas syringae pvs. - syringae (Pss) and morsprunorum race 1 (Psm) on the sweet cherry in both field and laboratory conditions. Cycled inoculations of one-year-old branches indicated that the sweet cherry became sensitive to Psm race 1 earlier in the season (October) compared to Pss (November). The most severe infections occurred in the dormancy period (November), while the necroses formed in January and March were less in their length. Inoculations of the two-/three-year-old branches performed in November resulted in necrosis, with those induced by Pss being more aggressive. The January inoculations, however, resulted in less formed necroses in length. Laboratory tests performed on excised sweet cherry branches confirmed the results yielded by the field experiments, indicating that the dormancy period poses the greatest risk for the P. syringae pvs. infection. The isolation of Pss and Psm bacteria from naturally infected sweet cherry samples (cankers) during the summer indicated that the bacteria that persists in cankers in low numbers became active during autumn. Significant Pss and Psm race 1 epiphytic bacterial populations were noted during the spring, but decreased in the summer and increased again in the autumn, indicating the presence of inoculum reservoirs. The greater understanding of the control strategies aimed at the epidemiological factors should, thus, facilitate better disease outbreak management.

The double-spined bark beetle Ips duplicatus (Coleoptera: Curculionidae, Scolytinae) is an invasive forest pest having a broad range of coniferous hosts within Europe. We found this species to be also developing in the Serbian spruce Picea omorika. Ips duplicatus infested 14 (52%) of 27 P. omorika mature trees in an arboretum garden in northern Slovakia in Central Europe during the summer of 2019. Logs from the upper part of stems of P. omorika trees placed in eclectors in the laboratory, yielded a total of 179 individuals of three scolytine species, with prevalence of I. duplicatus. Our results show that I. duplicatus also colonized less likely host such as the Serbian spruce, causing threat to this ornamental tree and contributing to its mortality in urban habitats during hot and dry summer weather.

Sclerotinia sclerotiorum (Lib.) de Bary is the causal agent of white mould, stem, and fruit rot diseases on a wide variety of crop plants including cabbage (Brassica oleracea L.) in field and storage. Control of this pathogen by using commercial disease management methods is extremely difficult. Therefore, this study was performed to develop an alternative and effective control method for the diseases by using biocontrol bacteria - Bacillus subtilis (strains TV-6F, TV-17C, TV-12H, BA-140 and EK-7), Bacillus megaterium (strains TV-103B), and Bacillus pumilus (strains RK-103) on Petri plate assays and on red cabbage in pot assays. On Petri plates, all of the tested bacterial strains showed the zone of inhibition against the pathogen fungus ranging 15.00-26.50 mm. Their percentage inhibition rates and lesion length ranged 42.64-79.41% and 0.02-4.50 cm in pot assays, respectively. Consequently, our results indicated that especially B. subtilis strains TV-17C, TV-12H, and TV-6F can be used as bio control agent of S. sclerotiorum in red cabbage production.

Symptoms of non-specific bark necroses in beech trees of all ages have lately been described. We investigated the occurrence of bark necrotic disease in beech thicket and health status of the trees. Our objective was to examine how bark necrotic wounds persist and the regenerative potential of young beech thicket. The research experiment was carried out at two isolated localities in the Western Carpathians in the period 2015-2017. A terminal shoot (stem) and a lateral shoot (branch) of each of the 30 sampled beech trees were examined. Young beech stands were affected by the necrotic disease in 87-94% cases (stems 69-83%, branches 33-56%). Shoot diameter and age had a significantly negative linear correlation (P < 0.05) with the development of all analysed disease characteristics on the beech bark. The encouraging finding is a positive regenerative capacity of young beech trees. Over the same period more annual shoots were healed in comparison with those that were newly infected (10.8% on stems and 0.6% on branches).