Search Results (675)

Plant viruses cause substantial yield and quality losses worldwide, and their rapid evolution can erode deployed host resistance. This review synthesizes current knowledge of antiviral resistance and tolerance mechanisms, using barley yellow dwarf virus (BYDV) in cereals as an illustrative case study. We first summarize key layers of plant antiviral immunity, including pre-formed physical and chemical barriers, dominant and recessive resistance genes, RNA silencing, hormone-regulated defense signaling, and degradation pathways such as the ubiquitin–proteasome system and selective autophagy. We then discuss how these mechanisms are exploited in breeding and biotechnology, covering conventional introgression, marker-assisted selection, QTL mapping and pyramiding, induced variation (mutation breeding and TILLING/ecoTILLING), transgenic strategies (pathogen-derived resistance and plantibodies), RNA interference-based approaches, and CRISPR-enabled editing of susceptibility factors. Finally, we highlight emerging nano-enabled tools and propose integrated strategies that combine genetic resistance with surveillance and vector management to improve durability under climate change and ongoing viral diversification. Full article

Fungal diseases continue to limit global crop production and drive major economic losses. Conventional diagnostic and control approaches depend on time-consuming culture-based methods and broad-spectrum chemicals, which offer limited precision. Advances in molecular identification have changed this landscape. PCR, qPCR, LAMP, sequencing and portable platforms enable rapid and species-level detection directly from plant tissue. These tools feed into RNA-based control strategies, where knowledge of pathogen genomes and sRNA exchange enables targeted suppression of essential fungal genes. Host-induced and spray-induced gene silencing provide selective control without the long-term environmental costs associated with chemical use. CRISPR/Cas9 based tools now refine both diagnostics and resistance development, and bioinformatics improves target gene selection. Rising integration of artificial intelligence indicates a future in which disease detection, prediction and management connect in near real time. The major challenge lies in limited field validation and the narrow range of fungal species with complete molecular datasets, yet coordinated multi-site trials and expansion of annotated genomic resources can enable wider implementation. The combined use of molecular diagnostics and RNA-based strategies marks a shift from disease reaction to disease prevention and moves crop protection towards a precise, sustainable and responsive management system. This review synthesizes the information related to current molecular identification tools and RNA-based management strategies, and evaluates how their integration supports precise and sustainable approaches for fungal disease control under diverse environmental settings. Full article

The use of acoustic communication and the relatively small antennae possessed by cicadas has led to the suggestion that antennal functions, specifically olfaction, are poorly developed in cicadas. The first step in determining antennal functions is to investigate the fine antennal structure. Scanning electron microscopy was used to visualize the morphology of the antennal sensilla in a diverse group of North American cicadas. The sensilla types and their distribution on the antennae of 30 species representing 12 genera, 6 tribes, and 3 subfamilies of North American cicadas are described and/or illustrated. Seven main classes and several subclasses of antennal sensilla were found: sensilla trichodea, sensilla chaetica, sensilla coeloconica, sensilla styloconica, foramina olfactoria, sensilla campaniformia, and sensilla cavitata-peg. Unique sensilla types and/or organizations of sensilla were found in many of the genera and differences between species of some genera were also present. No sexual dimorphism within species was found in the types or organizational patterns of the sensilla. The diversity of sensilla provides additional data for taxonomy and phylogenetic analyses. The potential function of the various sensilla types is hypothesized. Although relatively small, the antennae of cicadas are likely to provide significant information about their environment and increase their survival, including the selection of specific host plants and microhabitat selection observed in many species. Full article

Plant-based fermented foods are increasingly promoted for glycemic control, yet their mechanisms and clinical impact remain incompletely defined. This narrative review synthesizes mechanistic, preclinical, and human data for key matrices—kimchi and other fermented vegetables, tempeh/miso/natto, and related legume ferments, kombucha and fermented teas, plant-based kefir, and cereal/pulse sourdoughs. Across these systems, microbial β-glucosidases, esterases, tannases, and phenolic-acid decarboxylases remodel polyphenols toward more bioaccessible aglycones and phenolic acids, while lactic and acetic fermentations generate organic acids, exopolysaccharides, bacterial cellulose, γ-polyglutamic acid, γ-aminobutyric acid, and bioactive peptides. We map these postbiotic signatures onto proximal mechanisms—α-amylase/α-glucosidase inhibition, viscosity-driven slowing of starch digestion, gastric emptying and incretin signaling, intestinal-barrier reinforcement, and microbiota-dependent short-chain–fatty-acid and bile-acid pathways—and their downstream effects on AMPK/Nrf2 signaling and the gut–liver axis. Animal models consistently show improved glucose tolerance, insulin sensitivity, and hepatic steatosis under fermented vs. non-fermented diets. In humans, however, glycemic effects are modest and highly context-dependent: The most robust signal is early postprandial attenuation with γ-PGA-rich natto, strongly acidified or low-glycemic sourdough breads, and selected kombucha formulations, particularly in individuals with impaired glucose regulation. We identify major sources of heterogeneity (starters, process parameters, substrates, background diet) and safety considerations (sodium, ethanol, gastrointestinal symptoms) and propose minimum reporting standards and trial designs integrating metabolomics, microbiome, and host-omics. Overall, plant-based ferments appear best positioned as adjuncts within cardiometabolic dietary patterns and as candidates for “purpose-built” postbiotic products targeting early glycemic excursions and broader metabolic risk. Full article

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi (Syd.), poses a serious threat to global soybean production. The main approach to managing this disease has been through repeated fungicide applications which have reduced efficacy due to fungicide resistance. Recently, spray-induced gene silencing (SIGS) through exogenous application of double-stranded RNA (dsRNA) has emerged as a promising approach for plant disease management. In the present study, twelve different dsRNAs targeting genes important for P. pachyrhizi urediniospore germination, infection of the host plant or resistant to commonly used fungicides were produced in Escherichia coli on a large scale. Nine of these dsRNAs significantly reduced ASR severity (by 24.0% to 81.1%) and fungal biomass (50.5% to 83.1%) compared to the control when applied as a foliar spray in our growth chamber studies. Three of the most effective dsRNAs targeting an acyltransferase (ACE), cytochrome B (CYTB1) and a reductase (S12) also significantly reduced disease severity (78.2 to 82.3%) and fungal growth (79.8 to 85.4%) compared to the control in the greenhouse studies. Further investigation of the P. pachryrhizi urediniospore germination and hyphal growth in the presence of these dsRNAs in vitro revealed these dsRNAs reduced the spore germination rate from 72.1% to 0.0–26.6% at 4.5 h and hyphal growth from 254.0 µm to 2.7–40.5 µm at 9 h, with dsRNA targeting the S12 gene being the most effective. These results highlight the potential of SIGS using selected dsRNAs as a sustainable strategy for managing ASR through suppressing urediniospore germination and hyphal growth. Full article

Sorghum (Sorghum bicolor L. Moench) is a major cereal crop cultivated in semi-arid regions, but its yield is often constrained by soilborne fungal pathogens that affect plant growth and grain quality. This study explored how Trichoderma-based bioinoculants restructure the structure and functional composition of fungal communities in distinct sorghum compartments (soil, root, seed, and stem) using ITS amplicon sequencing. Two cultivars, Kalatur and Foehn, were evaluated under control and inoculated conditions. Alpha diversity indices revealed that inoculation reduced overall fungal richness and evenness, particularly in seed and stem tissues, while selectively enhancing beneficial taxa. Beta diversity analyses (PERMANOVA, p < 0.01) confirmed significant treatment-driven shifts in community composition. LEfSe analysis identified Trichoderma and Mortierella as biomarkers of inoculated samples, whereas Fusarium, Alternaria, and Penicillium predominated in controls. The enrichment of saprotrophic and symbiotrophic taxa in treated samples, coupled with the decline of pathogenic genera, indicates a transition toward functionally beneficial microbial assemblages. These results demonstrate that Trichoderma bioinoculants not only suppress fungal pathogens but also promote the establishment of beneficial ecological groups contributing to plant and soil health. The present work provides insight into the mechanisms through which microbial inoculants modulate host-associated fungal communities, supporting their use as sustainable tools for crop protection and microbiome management in sorghum-based agroecosystems. Full article

The Chinese pepper buprestid beetle, Agrilus zanthoxylumi Li Meng Lou, 1989 (Coleoptera: Buprestidae), is a major trunk-boring pest affecting the yield and quality of Zanthoxylum bungeanum. Clarifying its feeding preferences among different pepper varieties and their associations with host-derived volatiles is important for understanding and improving effective management strategies. This study conducted feeding tests under no-choice and dual-choice conditions to evaluate the beetle’s feeding preferences among three Z. bungeanum varieties—Fugu, Dahongpao, and Feng. Gas chromatography-mass spectrometry (GC-MS) was employed to analyze leaf volatiles, with factor analysis and partial least squares discriminant analysis (PLS-DA) used to identify key volatiles. Results showed that A. zanthoxylumi exhibited the highest resting frequency and feeding amount on Z. bungeanum Fugu leaves, with the lowest on Z. bungeanum Dahongpao leaves. Significant differences in unique volatiles were observed among the three varieties. Z. bungeanum Fugu contained 17 unique components, including (E)-4-hexen-1-ol, (−)-limonene, and (−)-α-pinene, with significantly higher quantities than Z. bungeanum Dahongpao and bungeanum Feng. Multivariate analyses further revealed distinct distributions in volatiles, with γ-terpinene, α-terpineol, and linalyl acetate emerging as key compounds distinguishing varieties. These results indicate that the feeding preferences of A. zanthoxylumi are closely related to host volatiles, suggesting variety-specific compounds may serve as primary chemical cues driving its preferences. Full article

Parasitoids are key natural antagonists of forest insect pests and are gaining importance in integrated forest protection under increasing climate-related disturbances. This study aimed to quantify the influence of vegetation diversity and canopy structure on the abundance and diversity of the overall insect community responses to vegetation structure and to provide an ecological context. Second, detailed analyses focused on three focal parasitoid families (Braconidae, Ichneumonidae, Tachinidae), which are of particular relevance for integrated forest protection due to their central role in integrated forest protection and in pesticide-free regulation approaches for risk mitigation in forest ecosystems. Malaise traps were deployed at eight randomly selected broadleaf and coniferous sites, and insect samples from six sampling dates in summer 2024 were analyzed. The sampling period coincided with the full development of woody and vascular plants, representing the phase of highest expected activity of phytophagous insects and associated parasitoids. Vegetation surveys (Braun–Blanquet), canopy closure, and canopy cover were recorded for each site. Across all samples, five arthropod classes, 13 insect orders, and 31 hymenopteran families were identified, with pronounced site-specific differences in community composition and abundance. Our results suggest that broadleaf-dominated sites, characterized by higher plant species richness and greater structural heterogeneity, support a more diverse assemblage of phytophagous insects, thereby increasing host availability and niche diversity for parasitoids. Parasitoid communities generally showed higher diversity at broadleaf sites. Spearman correlations and multiple linear regressions revealed a strong negative relationship between canopy cover and total insect abundance ρ (Spearman’s rank correlation coefficient (Spearman ρ = −0.72, p = 0.042; p = 0.012, R² = 0.70), R² (coefficient of determination), whereas parasitoid diversity (Shannon index) and the relative proportion of Ichneumonidae were positively associated with canopy cover (ρ = 0.85, p = 0.008). In addition, canopy cover had a significant positive effect on overall insect diversity (Shannon index; p = 0.015, R² = 0.63). Time-series analyses revealed a significant seasonal decline in parasitoid abundance (p < 0.001) and parasitoid diversity (p = 0.018). Time-series analyses revealed seasonal dynamics characterized by fluctuations in parasitoid abundance and diversity and a general decrease over the course of the sampling period. The findings demonstrate that structurally diverse mixed forests, particularly those with a high proportion of broadleaf trees mixed forests with heterogeneous canopy layers can enhance the diversity of specialized natural enemies, while dense canopy cover reduces overall insect abundance. These insights provide an ecological basis for silvicultural strategies that strengthen natural regulation processes within integrated forest protection. Full article

Agroathelia (syn. Sclerotium) is a global soil-borne pathogen with a broad host range, causing significant agricultural losses in diverse crops. However, genomic and population genetic resources of this genus remain limited. To develop genome-based molecular tools, we newly sequenced two Korean isolates (A. rolfsii KACC 93004P and A. delphinii KACC 93031P) and compared them with the reference genome of A. rolfsii GP3. Comparative genome analysis identified 723 polymorphic simple sequence repeat (SSR) loci, from which 14 were selected and validated across 34 Korean isolates representing multiple host plants. Genetic diversity was assessed using the number of alleles (NA), observed heterozygosity (Ho), unbiased expected heterozygosity (He), and polymorphic information content (PIC). Most SSRs were moderately to highly informative (PIC = 0.341 to 0.541 in A. rolfsii; 0.367 to 0.612 when including A. delphinii). Unweighted pair group method with arithmetic mean (UPGMA) clustering based on SSR allele profiles clearly separated the two species and revealed a distinct intraspecific structure within A. rolfsii. Principal coordinates analysis (PCoA) also revealed clear species-level separation, while A. rolfsii isolates were partitioned into two intraspecific clusters with one divergent isolate, indicating structured genetic variation without a host-associated population structure. The developed SSR markers provide useful tools for studying genetic diversity, population structure, and epidemiology of Agroathelia species and isolates. Full article

The olive tree hosts diverse endophytic fungi that may contribute to plant protection and growth. In this study, a preliminary screening of olive-associated fungal endophytes was conducted. A total of 67 fungal endophytes were isolated from the leaves and roots of the Greek cultivars Amfissa and Kalamon and identified using morphological and molecular approaches; 28 representative strains were selected for functional evaluation. Dual culture assays revealed substantial antagonistic activity against major phytopathogens, with growth inhibition ranging from 19.05% to 100%. Notably, strains F.KALl.8 and F.AMFr.15 showed the strongest suppression across pathogens. Interaction phenotyping revealed all major interaction types (A, B, C) and subtype C1/C2, with several strains producing pigmentation zone lines or hyphal ridges at contact sites. The assessment of plant growth-related effects using Arabidopsis thaliana as a model system showed that three strains (F.AMFr.15, F.KALr.4, F.KALr.38A) significantly increased seedling biomass (up to ~16% above the control), whereas nine strains caused severe growth reduction and disease symptoms. Beneficial strains also altered root architecture, inhibiting primary root elongation while inducing extensive lateral root formation. Collectively, these findings highlight the functional diversity of olive-associated fungal endophytes and identify promising candidate strains, particularly F.AMFr.15 (identified as Clonostachys sp.), for further host-specific validation as potential biological control and plant growth-promoting agents. Full article

Plants secrete a heterogenous population of membrane-enclosed extracellular vesicles that harbour an incredible diversity of molecular cargo. It is the complexity of the molecular cargo encapsulated by plant extracellular vesicles (PEVs) which facilitates the fundamental role PEVs play in mediating communication and signalling. PEV molecular cargo is composed of a diverse mixture of lipids, metabolites, proteins, and nucleic acids. Among the nucleic acids, the microRNA (miRNA) class of small regulatory RNA can be viewed as one of the most biologically relevant. Plant miRNAs regulate the expression of genes essential for all aspects of development as well as to control the gene expression changes required to drive the adaptive and defensive responses of plants to environmental stress and pathogen attack. Furthermore, recent research has shown that specific miRNA cohorts are selectively packaged into PEVs as part of the molecular-level response of a plant to its growth environment. For example, PEVs are loaded with a specific miRNA population for their targeted delivery to sites of pathogen infection in the host plant, or for cross-kingdom delivery of host-plant-encoded miRNAs to the pathogen itself. Here we outline PEV physical properties, compare PEV biogenesis pathways, detail the composition of PEV molecular cargo, and go on to provide detailed commentary on the role of PEV-delivered miRNAs in plant development, environmental stress adaptation, and pathogen defence. We conclude this article with a proposal for the potential future use of PEVs and their miRNA cargo in agriculture and aquaculture. Full article

Chalcidoids (Hymenoptera: Chalcidoidea), the most important natural enemies of parasitoids, serve as a pivotal factor in the regulation and management of pest populations. Microbiotas mediate interactions among plants, herbivores, and natural enemies and shape host immunity, parasitoid development, and gall formation; however, the niche-specific diversity and functions of tritrophic parasitoid–host–gall systems remain unclear. Focusing on leaf galls induced on twisted willow (Salix matsudana f. tortuosa) by the willow-galling sawfly Euura viminalis and on two chalcidoids, Eurytoma aethiops and Aprostocetus sp., we profiled bacterial and fungal microbiomes across plant surfaces, gall lumen, host larval tissues, and parasitoids using HTAS. Fungal diversity peaked on parasitoids but was depleted in the gall lumen and host tissues; bacterial richness showed the opposite trend, peaking in the gall lumen and decreasing on parasitoids. In networks contrasted by kingdom, fungi showed positive interface-hub connectivity (Cladosporium, Alternaria), whereas bacteria showed negative hub-mediated associations (Pseudomonas, Acinetobacter), indicating habitat-specific replacements: exposed niches favored transport, two-component, secretion–motility and energy functions, whereas the gall lumen reduced transport/motility but selectively retained N/S metabolism; and in host tissues, information processing and nitrogen respiration were highlighted. These results inform microbiome-guided parasitoid biocontrol. Full article

The Colorado potato beetle (CPB) is the primary defoliator of potatoes and is notorious for its ability to develop resistance to various insecticides. This remarkable adaptability may partly reflect selective pressures imposed due to the beetle’s coevolution with toxic Solanaceous host plants. As the initial interface between the environment and the insect olfactory system, odorant-binding proteins (OBPs) may sequester excess harmful molecules, such as insecticides and plant allelochemicals, in the perireceptor space, mitigating deleterious effects on vulnerable olfactory sensory neuronal dendrites. In this study, we identified an antenna-specific OBP (LdecOBP33) that is significantly upregulated in a pesticide resistant strain compared to a susceptible one. Competitive displacement fluorescence binding assays demonstrated that the LdecOBP33 protein exhibited broad affinity toward a range of plant volatiles and insecticides. Silencing LdecOBP33 decreased the beetle’s resistance to imidacloprid and impaired its ability to locate host plants. Together, these findings provide insight into a key molecular factor involved in the CPB’s response to environmental challenges, suggesting a potential link between insects’ adaptation to xenobiotics and their olfactory processing. Full article

Breeding for disease-resistant varieties is a sustainable solution to reduce substantial production losses caused by pathogenic infestations in Brassica vegetables, bypassing environmentally risky disease management practices. Host-resistant genetic mechanisms aid breeders to identify resistance loci and linked markers for the clubroot, Fusarium yellows, downy mildew, black rot, stem rot, soft rot, white rust, and turnip mosaic virus diseases in Brassica vegetables. Introgression of the resistance (R) genes by marker-assisted selection (MAS) breeding strategies allow the development of disease-resilient varieties. Brassica rapa clubroot-resistant genes (CRa, CRc, CRd, CRk, and Crr5) have been introgressed into Chinese cabbage, while CR genes (CRa, CRb, CRc, Crr1, Crr2, and Crr3) from B. rapa were also introgressed into B. oleracea. Beyond MAS, R genes can be precisely engineered by CRISPR-based technologies into precise and durable resistant varieties. The involvement of DNA methylation and histone modifications epigenetically regulate resistance mechanisms, often via ethylene/salicylic acid/jasmonic acid signaling pathways. DNA methylation mediates systemic acquired resistance by the differential expression of genes such as JAZ1, PR3, and NDR1. Future progress will depend on identifying epiQTLs and epi-markers linked to R genes. Epigenetic insights with genetic knowledge will facilitate breeding of biotic stress-resilient Brassica vegetables. This review synthesizes current molecular understanding of biotic stressors and provides future directions for disease resistance breeding of Brassica vegetable plants. Full article

The rhizosheath plays a critical but poorly understood role in plant–microbe interactions. However, it still remains unclear how host selection versus geographical isolation contributes to microbial community assembly within the rhizosheath. This study characterized the bacterial and fungal communities in the rhizosheath and surrounding bulk soil of Leymus racemosus using 16S rRNA and ITS high-throughput sequencing. Results showed that the bacterial community was strongly shaped by host selection within the rhizosheath, based on significantly reduced α-diversity and distinct β-diversity (Permutation tests, p < 0.001) compared to bulk soil. Furthermore, the core bacterial community structure was highly similar between the two geographically separated sites (PERMANOVA, p = 0.089). In contrast, the fungal community exhibited weaker habitat specificity but showed significant, though weak, geographical divergence (β-diversity, Permutation tests, p = 0.028). The explanatory power of geographical distance for fungal community variation was low (R² = 0.095) and less than that of the rhizosheath microhabitat (R² = 0.142). In conclusion, the rhizosheath imposes a strong filtering effect on bacterial communities. The weaker habitat specificity and stronger geographical signal observed for fungi suggest potential regulation by local dispersal limitation or historical colonization processes. This study provides insights into the assembly mechanisms of the plant rhizosphere microbial community. Full article