Fusarium oxysporum f. sp. lycopersici (Fol) is a soil-borne pathogen that causes vascular wilt in tomatoes, severely affecting yield and quality. Grafting susceptible scions onto resistant rootstocks is a promising control strategy. This study evaluated four resistant tomato accessions (LE314, LE472, LE482, and LE501) for their ability to suppress Fol translocation and support scion performance. PCR analysis showed that all resistant accessions restricted Fol movement beyond the roots, with no detection in shoot tissues, indicating effective containment of the pathogen. Gene expression profiling revealed distinct temporal and accession-specific responses of LRR, WRKY41, and PR-1 genes. In field trials, heterografted tomatoes remained symptomless across planting years, while self-grafted plants exhibited severe wilt symptoms. All grafted combinations achieved 100% success without signs of incompatibility. Growth parameters (plant height, branch number, and canopy diameter), fruit size, and yield did not differ significantly between self- and heterografted plants. Importantly, fruit quality assessment indicated that specific traits, particularly total soluble solids and fruit firmness, were influenced by scion-rootstock interactions, while fruit pH and color attributes (L*, a*, b*) remained stable across grafted treatments. These results confirm that resistant rootstocks can prevent Fol infection and maintain agronomic performance, supporting intraspecific grafting as an effective and sustainable approach for managing Fusarium wilt in tomato production.

Producing virus-free planting materials is fundamental to sustainable fruit tree cultivation, particularly for high-value crops such as apple (Malus domestica) and grapevine (Vitis vinifera). Given the systemic and persistent nature of most plant viruses and viroids, effective elimination remains a major challenge within a tissue culture-based propagation system. Therefore, this review aims to provide a comprehensive overview of conventional virus elimination strategies—including thermotherapy, meristem and shoot tip culture, chemotherapy, and electrotherapy—while highlighting their respective strengths and limitations. Concurrently, advancements in virus detection technologies have significantly enhanced the sensitivity, speed, and precision of virus indexing, enabling the early detection of low-titer or latent infections in plantlets cultured in vitro. Besides eradication strategies, increasing attention is directed toward virus inhibition approaches. RNA interference-based methods and plant-derived antiviral agents demonstrate promising antiviral activity in tissue-cultured apples and grapevines, offering chemical-free and eco-friendly alternatives. These biologically based inhibition strategies are particularly well-suited for integration into existing micropropagation systems. Collectively, this review emphasizes the importance of combining conventional sanitation methods with next-generation diagnostics and innovative biological inhibition technologies to develop robust, scalable, and sustainable protocols for virus-free certification.

Plant pathogenic fungi modulate host immunity by secreting nuclear effectors that interact with host nucleic acids and proteins within the host nucleus. Nuclear effectors are widely known to possess a nuclear localization sequence (NLS) that allows them to enter the host nucleus through either the classical importin α-mediated or non-classical pathways. However, the conserved motif in NLS and the mechanism behind successful nuclear trafficking of fungal nuclear effectors remain largely unexplored. MoHTRs, the nuclear effectors of Magnaporthe oryzae, reprogram the transcription of host immunity-associated genes. Recent research has demonstrated that MoHTR1 requires a classical NLS for importin α-mediated entry into the host nucleus and towards the pathogenicity of M. oryzae. However, the NLS of other fungal nuclear effectors, such as MoHTR2, needs further investigation. In this study, we report that MoHTR2 does not interact with rice importin αs or βs. By performing serial truncation and site-directed mutagenesis, we identified 53HH54 as the core NLS motif essential for the nuclear localization of MoHTR2. We also found that the double histidine in MGG_13063, a nuclear effector candidate of M. oryzae, is involved in its nuclear localization. Deletion of the MoHTR2 core NLS reduced the invasive hyphal growth and lesion formation by M. oryzae. These findings enhance our understanding of the molecular mechanisms underlying the nuclear localization of fungal nuclear effectors and their roles in pathogenicity, contributing to a broader understanding of host-pathogen interactions.

Magnaporthe oryzae is the causal agent of rice blast disease, a major threat to global food security. Although M. oryzae infects a broad range of monocotyledonous plants, it fails to colonize dicot species such as Nicotiana benthamiana, offering a useful system to investigate nonhost resistance (NHR). In this study, we characterized the immune responses of N. benthamiana to M. oryzae by profiling defense-related gene expression, analyzing fungal invasion, and functionally dissecting key immune components. Time-course expression analyses revealed sustained upregulation of NbBAK1, NbEAS, NbWRKY22, and NbPR1, alongside dynamic regulation of NbCYP71D20 and NbSGT1. Virus-induced gene silencing demonstrated that silencing of NbSGT1, but not NbEAS or NbBAK1, significantly enhanced fungal colonization. Furthermore, salicylic acid (SA)-deficient NahG plants exhibited increased susceptibility, suggesting that SA and SGT1-dependent immunity synergistically contribute to NHR. Visualization of infection using a GFP-expressing fungal strain confirmed that suppression of SGT1 and SA signaling facilitated hyphal expansion into adjacent host cells. High-throughput screening of 179 M. oryzae candidate effectors revealed that 70 induced hypersensitive response-like cell death in N. benthamiana, a response that was abrogated by NbSGT1 silencing. These findings collectively demonstrate that SA signaling and SGT1-dependent effector-triggered immunity are critical barriers against M. oryzae invasion and highlight the potential of nonhost immune components as resources for engineering durable resistance in crops.

The rhizosphere microbiome of Panax ginseng plays a crucial role in promoting plant growth, enhancing stress resilience, and facilitating the biosynthesis of pharmacologically significant ginsenosides. However, continuous monocropping disrupts the microbial community balance, leading to soil degradation, the proliferation of soilborne pathogens, and decreased crop productivity. Advanced multi-omics technologies, such as metagenomics and metabolomics, have provided valuable insights into the structure and function of the ginseng rhizosphere microbiome. These studies highlight its potential for nutrient mobilization, disease suppression, and stress mitigation. Root exudates, including phenolic acids and ginsenosides, influence microbial composition; however, they may also exacerbate soil imbalances by promoting pathogenic fungi. Conversely, beneficial microbes, such as phosphate-solubilizing bacteria and siderophore-producing strains, enhance nutrient availability, mitigate heavy metal toxicity, and suppress pathogens through bioactive metabolites. This review emphasizes the functional roles of the ginseng rhizosphere microbiome and highlights knowledge gaps in leveraging microbial interactions for sustainable cultivation. A more comprehensive understanding of plant-microbe interactions, coupled with the integration of microbiome-driven strategies, can enhance ginseng productivity, boost bioactive compound yields, and support environmentally sustainable agricultural practices. These findings provide a foundation for advancing microbiome research and addressing challenges in ginseng cultivation.

Disease dynamics are significantly influenced by insect vectors through their interactions with viruses and host plants. The objective of this study is to understand how increased temperatures affect virus transmission, providing insights critical for developing climate-resilient pest and disease management strategies. We investigated the effects of temperature on the survival and growth of Myzus persicae (Sulzer) (Hemiptera: Aphididae), a key vector of the cucumber mosaic virus (CMV). Experiments were conducted to assess aphid survival, reproduction, and intrinsic rate of increase on healthy and CMV-infected Nicotiana tabacum plants at 25℃ and 30℃. It was observed that higher temperatures did not negatively affect aphid survival. CMV transmission assay was performed by allowing aphids to acquire and inoculate the virus under varied temperature combinations, while the aphid feeding behavior was monitored at different temperatures. The transmission efficiency was markedly reduced at 30℃ compared to 25℃, regardless of variations in temperature during virus acquisition and inoculation. Analysis of probing behavior revealed that aphids' probing behavior differed at 30℃, likely contributing to reduced transmission efficiency at higher temperatures. These findings demonstrate the intricate interplay between temperature, vector behavior, and virus transmission. Together, this study emphasizes the importance of incorporating environmental temperature dynamics into the development of sustainable and climate-resilient strategies for managing vector-borne diseases in agriculture.

Fusarium head blight (FHB) is an important disease reducing yield and quality of wheat and barley. To study changes in fungicide efficacy over time, 161 FHB isolates (F. asiaticum and F. graminearum) were obtained from infected wheat and barley in the Jeolla provinces of the Republic of Korea from 2010-2013 and 2020-2023. Over 10 years, FHB fungi developed resistance to demethylation inhibitors (DMIs), methyl benzimidazole carbamates (MBCs), and phthalimides, with few exceptions. Also, no significant resistance against succinate dehydrogenase inhibitors (SDHI) and quinoneoutside inhibitors (QoI) was observed, but sensitivity to phenylpyrrole (PP) increased. Mycotoxin production by four representative isolates of both species indicated that higher doses of DMI, DMI + DMI, MBC, MBC + DMI, and PP controlled trichothecenes, whereas zearalenone was controlled only by SDHI. QoI, QoI + DMI, and phthalimide did not control mycotoxin production in either species. Despite resistance development, DMI, MBC, and PP can still be used to control FHB and mycotoxins in wheat and barley in Korea with close monitoring of resistance.

Colletotrichum and Fusarium are globally important plant-pathogenic fungi that cause serious diseases in chili pepper and other crops, leading to substantial yield losses due to their broad host range, environmental persistence, and the limited effectiveness of chemical control, thereby highlighting the need for sustainable alternatives such as biological control. We investigate the biological control and plant growth-promoting potential of Burkholderia vietnamiensis FBCC-B8049, isolated from freshwater environments. The strain exhibited significant antifungal activity against Colletotrichum gloeosporioides, Colletotrichum acutatum, and Fusarium oxysporum in dual-culture assays, with stronger effects against Colletotrichum species. The inhibition was likely due to direct antagonism and volatile organic compounds (VOCs) produced by FBCC-B8049, which were particularly effective against Colletotrichum species. Additionally, FBCC-B8049 demonstrated plant growth-promoting activities including siderophore production for iron acqusition, phosphate solubilization for enhanced nutrient availability, and indole-3-acetic acid synthesis to promote root development. These combined activities enhance nutrient availability and promote seed germination and seedling growth in chili pepper. Ex vivo assays further revealed the effectiveness of FBCC-B8049 in suppressing anthracnose disease on pepper fruits through both direct application and bacterial VOCs emission. Phylogenetic analysis of 16S rRNA and recA gene sequences positioned FBCC-B8049 closely to Burkholderia vietnamiensis, a known plant growth-promoting rhizobacterium. These findings highlight FBCC-B8049 as a promising candidate for sustainable agricultural applications.

Streptomyces species are well-known for their antifungal properties and the production of diverse secondary metabolites, including non-ribosomal peptides and polyketides. These metabolites can be identified through various genetic techniques, allowing for the investigation of gene functions using whole-genome databases. Numerous studies have explored the genetic functions of Streptomyces using advanced techniques, such as CRISPR-Cas9 mutagenesis, to generate site-specific mutant strains. In this study, we re-identified Streptomyces sp. J6 as Streptomyces anandii J6 through whole-genome sequencing and average nucleotide identity (ANI) analysis. The type II and type III polyketide synthase clusters (PKS: clusters 9, 10, and 12) were further studied using CRISPR-Cas9 for functional analysis, revealing the role of srsA in the biosynthesis of alkylresorcinols, which are phenolic lipids with antifungal properties. These results indicate that metabolites belonging to the polyketide family produced by Streptomyces plays a significant role in the biocontrol activity of microorganisms against plant diseases. Furthermore, the findings suggest that specific PKS profiling enables the rapid and efficient screening of a large number of microbial candidates, thereby facilitating the selection of promising biocontrol agents.

Various strategies have been developed to control lettuce diseases on farms and in food-packing plants. Biological control is considered a promising alternative owing to its eco-friendly nature. In the present study, bacteria isolated from coastal mudflats were evaluated for their efficacy in controlling Sclerotinia rot, and the plant growth-promoting activity in lettuce was also assessed. Among the screened microorganisms from the coastal mudflats, 12 bacterial strains exhibited antifungal activity against Sclerotinia sclerotiorum selected. These isolates have shown beneficial characteristics, such as nitrogen fixation, indole-3-acetic acid production, phosphate solubilization, and siderophore production. Additionally, the selected isolates showed antifungal effects on the pathogens of major plant disease, such as Alternaria porri, Colletotrichum acutatum, Fusarium oxysporum, Phytophthora capsici, Pythium ultimum, Rhizoctonia solani, and Stemphylium lycopersici. Among the selected bacterial strains, Bacillus subtilis GCM190 exhibited a high sclerotinia rot control rate, similar to that of the tebuconazole-treated group, and showed a significant effect in promoting the growth of lettuce leaves, stems, and roots (least significant difference, P = 0.05). The selection of rifampicin-resistant mutants and their tracing on lettuce roots and soil confirmed that they were well established in both the soil and lettuce roots. The selected microorganisms also exhibited antifungal effects in vitro against other crop diseases affecting cucumbers, tomatoes, red peppers, and green onions, suggesting high potential for practical applications.