Fulltext search in archive

This study aims to evaluate the efficiency of basalt with two botanical aqueous extracts of Citrus aurantium and Nerium oleander (50g/L) against Aphis punicae and Planococcus citri in an organic pomegranate orchard. Basalt was applied as a foliar spray with two doses (1.5% and 3%), in the ground as a fertiliser (1.5%), and as a combined application (1.5%). Phenolic compounds of both plants were identified by HPLC-PDA/ESI-MS analysis. Seven and six flavonoids were detected in C. aurantium and N. oleander extracts, respectively. Hesperidin was more abundant in C. aurantium extracts; however, N. oleander extracts contained more quercetin rutinoside. A. punicae populations were significantly higher in control trees compared to the treated ones. A. punicae mortality rates reached high values above 90% for basalt and plants extracts and efficacy rates exceeded 80%. P. citri mortality rates reached 88% and 77%, and efficacy rates exceeded 75% and 66% for basalt and plant extracts, respectively. These findings may help to plan Integrated pest management strategies in organic orchards to avoid toxic chemical pesticides.

Hop stunt viroid (HSVd) infects various plants such as citrus, hop, almond, grapevine, pear, plum, peach, mulberry, fig, and pistachio. Medlar trees in an orchard in Malatya province of Türkiye were surveyed for the presence of HSVd in 2021. Twenty leaf and flower samples were collected and tested by RT-PCR methods using pathogen-specific primers. HSVd was found in five of the twenty medlar samples showing novel sequence variations. Two of the five HSVd variations were chosen at random and registered in GenBank. Both Turkish HSVd isolates had genomes that were 300 nucleotides long. The complete genome sequence of these variations was compared to isolates in GenBank. The nucleotide sequences of HSVd isolates exhibited 89.7–100% similarity with HSVd isolates found in various crops worldwide. Analysing the alignment of multiple sequences and conducting phylogenetic analyses revealed that identified HSVd variants clustered with citrus Türkiye (MZ995256), citrus Italy (KC584022), citrus Iran (GQ260203) and citrus Japan (X06719) isolates with 100% similarity rate and citrus China (FJ716172) and citrus Spain (AF213503) isolates with 99.5% and 98.0% similarity rates, respectively. To our knowledge, this is the first report of medlar serving as a natural host for HSVd. HSVd infection in medlar could be a problem in the future, and additional study is needed. The infection appears to be latent, but it might be a source of infection for susceptible plants.

The genus Alternaria has a global distribution and consists of a diverse group of pathogens. Plant-pathogenic Alternaria spp. can reduce the crop yield and pose serious threats to agricultural production. The pathogen A. mali is recognised as the key the pathogenic mechanism in the early defoliation of apples, which produces the host specific toxin (HST) that was named as an apple specific toxin (a specialised toxin of A. alternata pv. mali, AM toxin). The phenomenon of horizontal transfer of the AM toxin gene from different strains of A. alternata was found, and the relationship between the AM toxin and pathogenicity was confirmed. The representative strain A. tuberculata with the AM toxin gene was co-cultured with sixteen Alternaria strains without the AM toxin gene. As a result, four strains from different Alternaria species obtained the AM toxin gene, which indicated that the AM toxin gene can transfer among different Alternaria species. The AM toxin gene is easy to be lost after subculture, and high temperature and low nutrition can promote this loss. The symptoms of the Alternaria pathogen with or without the AM toxin gene are obviously different on the host. When infected by a pathogen with the AM toxin gene, green spots formed on the apple leaves, and rotten disease spots appeared in the fruit carpels. Contrary to this, when infected by a pathogen without this gene, only small epidermal spots without chlorosis formed on the apple leaves, and mildew-heart spots appeared in the fruit carpels.

Common ragweed – Ambrosia artemisiifolia L. (Asteraceae) is an invasive plant species in Europe native to North America. Most of the records of known eriophyid mites on different ragweed species are from their native range. Our field experiments in Slovakia, 2016–2023, aimed to identify specific species feeding on common ragweed. We searched for symptomatic plants and collected growing tips, which were then preserved in 70% ethanol for further study. A recently described species of eriophyid mite, Aceria artemisiifoliae Vidović & Petanović (Acari: Eriophyoidea), was found in western and eastern Slovakia. This is the first record of the species in Slovakia and the second record in the world. It remains unclear whether this species is invasive like Ambrosia, and whether it could be used as a potential biological control agent.

Drosophila suzukii poses a significant threat to berry fruits with its uncontrolled spread. Essential oils (EOs) have emerged as potential bioinsecticides due to their natural origin, mode of action, and biodegradability. Although EOs show potential for use in agriculture due to ecotoxicologically favourable characteristics, additional research is required to enhance their effectiveness, stability, and application for practical implementation in pest management. The primary objective of this research was the development of a bioinsecticide formulation based on a combination of three EOs – Pelargonium graveolens, Anethum graveolens, and Pinus sylvestris followed by the assessment of formulated bioinsecticide physicochemical properties. Using a two-choice bioassay, this study aimed to evaluate the effects of formulated bioinsecticides on D. suzukii, regarding their insecticidal properties through oviposition deterrence. The developed formulation exhibited favourable physicochemical properties and demonstrated a decrease in the number of larvae in fruits. Bioinsecticides present an environmentally friendly approach to pest control. However, further research and development are imperative to fully exploit their potential for effective crop protection in the field, followed by comprehensive research to evaluate the potential side effects on natural enemies, ensuring that their implementation doesn't harm beneficial organisms and maintain ecological equilibrium.

Species of the genus Xanthium (cocklebur) are invasive plants widespread all over the world. In Bosnia and Herzegovina, Xanthium orientale L. was an invasive species, while Xanthium spinosum L. was an economically harmful weed species. The reason these species are spread over vast areas and across various climate conditions must be attributed to their biology, particularly the biology of their seeds. Germination of populations of X. orientale and X. spinosum at a temperature range of 15 °C to 40 °C over 2 to 20 days ranged between 15.0% (X. spinosum) and 90.0% (X. orientale). By means of the application of a statistical model, a positive correlative dependence of temperature and time on seed germination was determined (X. orientale = 80.70%, X. spinosum = 62.20%), which provided a possibility of modelling the seed germination of Xanthium species in various ecological conditions. The optimal germination temperature for both cocklebur species was 30−35 °C. As the germination of seeds was recorded at all researched temperatures (15, 20, 25, 30, 35 and 40 °C), it points to a wide ecological valence for the considered abiotic factor. These results suggest that the unique germination biological characteristics of the Xanthium genus made it extremely easy for the species to form monodominant communities in new habitats and climate-changing environments quickly.

During the survey of open tomato fields in Vojvodina (Serbia), characteristic anthracnose disease symptoms, including black, circular, sunken, and watery lesions, were observed in about 20% of fruits in September 2018. Subsequent pathogen isolations formed white aerial mycelia and numerous spherical, black conidiomata on the Potato Dextrose Agar. Ten representative isolates produced hyaline, smooth-walled, cylindrical, and aseptate conidia. The presence of initially brownish necrotic lesions on the tomato, which later expanded into large rotted areas, ultimately leading to complete fruit rot, confirmed the pathogenicity of the tested isolates. Molecular identification was performed using Bayesian analysis of concatenated ITS, TUB2, CHS-1, and ACT loci. Based on the combination of the morphological and molecular features, the fungus Colletotrichum nigrum was identified as the causal pathogen. As this is the first report on this fungal pathogen on tomatoes in Serbia, it highlights the importance of early and accurate detection for effective disease prevention, thus reducing crop damage and market losses.

The new record of Dictyothrips betae Uzel, 1895 (Thysanoptera: Thripidae) after 72 years in Slovakia is presented. Dictyothrips betae is an important pest and one of the few thrips species known as vectors of dangerous plant tospoviruses, causing severe yield losses to economically important crops worldwide. D. betae was swept from an herbal layer in blown dunes in SW Slovakia.

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.

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.

White root disease is a significant disease of cashew caused by Rigidoporus sp. Five endophytic fungal isolates, namely AR31D (Fusarium proliferatum), AR42D (Penicillium citrinum), BR32C (Trichoderma asperellum), VNTB1 (Chaetomium sp.), and EAGS14 (Curvularia lunata), were assessed as the biocontrol agents against Rigidoporus sp. in vitro and in planta. The research objective was to obtain endophytic fungi that effectively control Rigidoporus sp. and their mechanisms. The in vitro test results showed that all isolates could inhibit Rigidoporus sp. and promote plant growth by producing volatile organic compounds, chitinase enzymes, and indole acetic acid. Meanwhile, only four isolates could solubilize phosphate with low-medium solubilization efficiency. The isolates successfully colonized the root of cashew saplings in 10–65%. The effectiveness of endophytic fungal isolates in controlling white root disease was determined by the mechanisms involved, such as resistance induction (increased activity of defense enzymes like polyphenol oxidase), chitinase enzyme production, indole acetic acid production, phosphate solubilization, and suppression of plant stress which observed from decreased malondialdehyde concentrations in saplings’ roots. Trichoderma asperellum and Chaetomium sp. were the best isolates with the highest control effectiveness and stimulating plant growth.

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.

Drought stress is among the significant forms of abiotic stresses that unfavourably affects maize survival as well as the development from germination to maturity. This paper, therefore, reviewed drought stress effects in maize plants and expatiated on the plausible adoptable mitigation measures to employ in curbing these effects as well. Water shortage prompts drought stress that alters the morphological, physiological and biochemical activities in maize plants. The major drought stress implications on the plant’s survival are mostly in the area of altered metabolic functions, including nutrient metabolism, cell membrane integrity, water relationships, plant yield, photosynthetic processes, osmotic adjustment, and the pigment content. Mitigating strategies, such as the breeding of drought-tolerant varieties, genomic applications for drought tolerance enhancement in maize plants, as well as the use of rhizobacteria and endophytic bacteria, can be employed in alleviating drought stress and ensuring optimal maize productivity.

Sugarcane (Saccharum officinarum L.) is a key cash crop, and its production is influenced by a variety of phytopathogens in different parts of the world. During consecutive field surveys, sugarcane stalks with red rot symptoms were observed in three provinces of Pakistan (Punjab, Sindh, and Khyber Pakhtunkhwa). Cane samples with visible symptoms were plated on Potato Dextrose Agar (PDA) media. Morphological and microscopic observations identified this pathogen as Colletotrichum falcatum. Comparative molecular study of amplified sequences of β-tubulin (Bt) and Actin (ACT) genes showed 100% similarity and ITS sequence showed 99% similarity with C. falcatum. For in vitro control of red rot, eight bacterial strains from the rhizosphere of sugarcane were isolated. These strains showed variable growth inhibition of C. falcatum in dual culture method. Among all tested strains, Bacillus amyloliquefaciens and B. altitudinis exhibited best antifungal activities. Based on these results, tested bacterial strains (B. amyloliquefaciens and B. altitudinis) can be recommended as effective biocontrol agents to manage red rot disease of sugarcane.

Fourteen fungicides and three marine-derived fungi were tested for their activities in the promotion of rice seedling development and their efficacy in controlling rice sheath blight disease in two rice varieties, RD43 and KMDL105, under greenhouse conditions. The results showed that the rice seeds treated with carbendazim 50%SC and azoxystrobin 25%SC displayed the best promotion of rice growth in root length and shoot height at seven and 14 days in rice var. RD43. Rice seeds from var. KMDL105 treated with thiophanate-methyl 70%WP exhibited significant stimulation of rice seedling growth resulting in the greatest increase in root length and shoot height at seven and 14 days. In pot experiments with rice var. RD43, spraying with triforine 19%EC, propiconazole 25%EC, trifloxystrobin 50%WG, and validamycin 3%SL showed a high level of fungicidal activity in controlling sheath blight disease, with this evidenced by significant suppression of the disease severity by 71–75% and 61–73% at seven and 14 days after inoculation, respectively. The treatment of rice var. KMDL105 with validamycin 3%SL exhibited the best activity in controlling sheath blight disease by reducing disease severity by up to 62% and 64% at seven and 14 days, respectively. The antagonistic marine fungi tested in this study displayed low activity against sheath blight disease and low effects on rice seedling promotion compared to fungicides. Specifically, Trichoderma harzianum KUFA 0689 and T. asperellum KUFA 0677 reduced sheath blight disease severity by 42–46% and 27–37% at seven and 14 days, respectively.

This study examined the effects of beneficial rhizobacterium Pseudomonas chlororaphis strain AFS009 and entomopathogenic fungus Beauveria bassiana strain GHA against plumeria rust Coleosporium plumeriae. Two preemptive or three curative laboratory experiments and a curative field experiment were conducted to examine the effects of these commercially available biocontrol products. Treatments included the application of B. bassiana at 1.23 g/L and P. chlororaphis at 3 or 9 g/L. Systemic fungicide azoxystrobin applied at 0.12 g/L and water were included as positive and negative controls, respectively. While its effect was insignificant in the field trial, B. bassiana reduced the rust pustule development in one of two preemptive and two of three curative laboratory trials. In contrast, P. chlororaphis applied at 9 g/L suppressed the number of rust pustules in both laboratory and field experiments, demonstrating its potential biological activity against plumeria rust. In the field trial, the effect of P. chlororaphis was observed at 14 days post-treatment, suggesting that an application interval of 14 days on infected plants can take the rust under control.

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 main purpose of the study was to examine the potential of crops, such as soybeans (Glycine max), sunflowers (Helianthus annuus), alfalfa (Medicago sativa), and sorghum (Sorghum bicolor), as trap crops for Halyomorpha halys. We monitored the abundance and seasonal dynamics of H. halys (egg clusters, larvae, and adults) on a selected number of various crops at 10-day intervals. The experiment was performed in two different regions of Slovenia (western and central) and in two different years (2021, 2022). The results varied depending on the location and the year. In the first experiment, data from the entire year showed that sorghum was the most attractive for H. halys adults (1.56 ± 0.12), followed by sunflowers (0.61 ± 0.05), soybeans (0.37 ± 0.03) and alfalfa (0.41 ± 0.21). In the second experiment, the abundance numbers of the pest were significantly lower compared to those of the first experiment [sorghum and soybeans (0.003 3 ± 0.002), sunflowers (0.000 3 ± 0.000 3)]. In both cases, the abundance numbers increased when all the crops entered the fruit development stage (BBCH 70+). Overall, the lower density of the H. halys population and the experimental design could also be some of the factors for such a low incidence of stink bugs in the central region of the country. More research will be needed to further develop effective control methods for this invasive pest.

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.

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.

Grape hyacinths are popular perennial, flowering bulbous plants. In 2018, 2019, and 2020, some plants of three Muscari species showed symptoms similar to those associated with phytoplasma infection in commercial ornamental gardens in Hungary. Symptoms included virescence of flowers and yellowing of leaves. Symptomatic and asymptomatic Muscari plants were sampled at two locations to detect and identify the pathogens involved. Total DNA was extracted from the plants and used as a template in polymerase chain reaction assays to amplify 16S rRNA gene sequences and housekeeping genes (tuf, secY) with phytoplasma-specific primers. The resulting PCR products from symptomatic plants were cloned and sequenced bidirectionally. Homology searching of the obtained sequences against the GenBank database indicated the presence of  'Candidatus Phytoplasma asteris' in the three Muscari species. This is the first report worldwide of C. P. asteris phytoplasma infecting M. botryoides and M. comosum, and its first identification in M. armeniacum in Hungary.

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 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 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.

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.

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.

Little cherry virus 1 (LChV1) of the genus Velarivirus is an important pathogen associated with the little cherry disease. It infects various species of the genus Prunus, mainly the sweet cherry and the sour cherry. Recently, plums and apricots have also been reported as natural hosts. In the present work, the LChV1 isolate causing chlorotic mosaics in almonds is characterised. The nearly complete (+)ssRNA genome sequence of the Alm138 isolate, obtained by Sanger sequencing, is 16 878 nt long showing a typical velarivirus structure with 8 ORFs. Among them, the taxonomically important ORFs, ORF1a/1b encoding the polyprotein is 8 421 nt long, with a 0/+1 frameshift position at 6 923; ORF3 encoding the heat shock protein HSP70h is 1 656 nt long, and ORF6 encoding the coat protein duplicate is 1 989 nt long. The genome sequence showed its highest identity with LChV1 isolates Apr184R (96.2%), 19SP003B (92.2%) and Kyoto-2 (92.1%). A similar situation was also found for the ORF1, HSP70h, and CP nucleotide and amino acid sequences. A phylogenetic analysis identified Alm138 as a member of the G5 phylogenetic group, supporting its close relationships with the Czech Apr184R apricot isolate and the other members of this group. This report describes the first little cherry virus 1 isolate infecting almonds and confirms the presence of isolates of the G5 phylogroup within Europe.

While monitoring the health of different ornamental and shade trees in Serbia, symptoms indicative of cypress canker disease were observed in young Cupressus sempervirens trees in the Belgrade urban area. Symptoms included tree mortality (specimens were recorded with a change in needle colour, branch decline or longitudinal bark cankers on the stems with resin exudates) and the appearance of acervuli fruiting bodies on the bark and cones. Using light microscopy, cross sections of fruiting bodies on the cankered bark and cones were examined and numerous fusoid, six-cell conidia were recorded with four inner coloured cells and two hyaline cells at the ends. Based on the unique combination of the morphological features and the infected host, this pathogen was identified as Seiridium cardinale. This is the first report of S. cardinale on the common cypress in Serbia. Possible introduction pathways and the implications of the findings are discussed.

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.

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.