Search Results (393)

Mitogen-activated protein kinase kinase kinases (MAPKKKs) are pivotal upstream regulators of MAPK cascades, integrating signals that coordinate plant development and stress responses. However, the specific functions of MAPKKKs, particularly within the MEKK subfamily, in mediating cotton resistance to Verticillium wilt and Fusarium wilt remain poorly characterized. To address this, we conducted a systematic, cross-species analysis of the MAPKKK family in four key cotton species: Gossypium arboreum, Gossypium barbadense, Gossypium hirsutum, and Gossypium raimondii. Genome-wide identification and phylogenetic analysis revealed 660 MAPKKK genes, classifying them into the MEKK, Raf, and ZIK subfamilies. Evolutionary analysis indicated that Whole-Genome Duplication (WGD) events were the primary driver of family expansion. Promoter cis-element and Gene Ontology (GO) enrichment analyses implicated these genes in hormone signaling and stress adaptation. Expression profiling demonstrated functional modularity, with distinct members responding specifically to cold stress or cooperatively to drought and salt stresses. Upon pathogen infection, members diverged into regulatory modules associated with immune homeostasis, tissue-specific defense, and core signaling potentially governing systemic acquired resistance (SAR). The temporal expression patterns of core candidate genes were validated by qRT-PCR. This study provides, for the first time, a comprehensive evolutionary and functional framework for the MEKK subfamily within the cotton MAPKKK family. It reveals the conserved and divergent roles of this subfamily in stress adaptation and identifies key candidate genes for breeding disease-resistant cotton varieties. Full article

Previous studies have demonstrated that Bacillus velezensis HN-Q-8 shows significant inhibitory effects against various plant pathogenic fungi causing potato diseases, primarily attributed to the production of fengycin. However, the low yield of fengycin in wild-type strains limits its practical application, and the influence of its biosynthesis pathway on volatile organic compound production remains unclear. In this study, to enhance fengycin production in Bacillus velezensis HN-Q-8, we applied metabolic engineering by targeting competitive pathways. Specifically, a double mutant (ΔsrfAAΔbaeBE) was constructed by knocking out the surfactin synthase gene srfAA and the bacillaene synthesis gene baeBE. The fengycin yield of the ΔsrfAAΔbaeBE mutant in the basal (sodium glutamate) fermentation medium reached 98.83 mg/L, representing a 2.39-fold increase over the wild-type strain. Subsequent medium optimization by supplementing peptone further boosted production to 155.61 mg/L, which was 3.77-fold higher than the wild-type level. The lipopeptide extract from the double mutant strain ΔsrfAAΔbaeBE demonstrated potentiated antifungal activity against four major potato fungal pathogens: Alternaria solani (early blight), Rhizoctonia solani (black scurf), Fusarium oxysporum (wilt), and Botrytis cinerea (gray mold). The active volatile compounds released by ΔsrfAAΔbaeBE, such as benzaldehyde and 2,5-dimethylpyrazine were significantly increased. The knockout of srfAA and baeBE also distinctly altered the physiology of the strain: the double mutant exhibited enhanced biofilm formation, an accelerated early growth rate followed by early decline, and a severely reduced sporulation capacity. These results confirmed the feasibility of molecularly modifying Bacillus velezensis HN-Q-8 to improve fengycin production and antifungal activity for further agricultural application. Full article

Fusarium wilt (FW), caused by Fusarium oxysporum, poses a significant threat to mungbean (Vigna radiata L.), impacting its yield and quality. In this study, a recombinant inbred line (RIL) population was developed by crossing the highly resistant cultivar Weilv 9002-341 with the highly susceptible line V1128. Assessment of resistance revealed a continuous variation in the average disease index within the resulting population, consistent with the inheritance pattern of quantitative traits. Leveraging an F_2:3 segregating population, we conducted linkage mapping analysis and bulked segregant analysis by sequencing, leading to the construction of a genetic linkage map and the identification of a region correlated with resistance. Within this region, 14 novel simple sequence repeat markers were designed to enable refined mapping. A putative resistance locus, spanning 0.17 Mb and encompassing 19 annotated genes, was precisely located. Ultimately, two genes were identified as high-priority candidates conferring resistance. The results of this study lay the foundation for the functional investigation of genes associated with resistance to Fusarium wilt disease in mungbean. Full article

Fusarium oxysporum f. sp. niveum is an increasingly threatening fungal pathogen that systemically colonizes watermelon plants and severely compromises their productivity by causing destructive vascular wilt disease. While its nonribosomal peptide synthetase NPS6 has been identified as a key virulence factor, the regulatory mechanisms through which it controls downstream gene networks to cause disease remain unclear. To elucidate this regulatory pathway, we constructed a ΔFW-NPS6 knockout mutant and conducted a comparative genome-wide analysis using RNA sequencing, with the wild-type strain as a control. The results revealed 66 NPS6-dependent differentially expressed genes, which were primarily associated with secondary-metabolite biosynthesis (e.g., genes encoding nonribosomal peptide synthetases like NPS2) and pathogen–host interactions (e.g., components of the MAPK signaling pathway), and were enriched in key pathogenic pathways. This finding reveals the virulence regulatory network mediated by NPS6, providing a direct theoretical foundation and crucial molecular targets for developing novel control strategies, such as targeted fungicides or genetic interventions, against Fusarium wilt in watermelon by highlighting NPS6 itself as a potential fungicide target and its downstream pathways (e.g., siderophore biosynthesis) as points for intervention. Full article

The agave wilt associated with Fusarium oxysporum (Fox) is a major disease of blue agave (Agave tequilana Weber var. azul), used to produce “Tequila” in Mexico. Little is known about the A. tequilana-F. oxysporum interaction yet understanding defense mechanisms against the pathogen is necessary for control strategies. During early Fox infection, plants trigger defense mechanisms to interrupt the compatible interaction, while Fox’s pathogenesis mechanism interacts with plant response. This study evaluated plant defense mechanisms induced by Fox in A. tequilana and their interaction with fungal pathogenesis. For this, an A. tequilana pathogenic strain (FPA), and the non-A. tequilana pathogenic strains FNPA and FOL were utilized. Early defense mechanisms evaluated were hypersensitive response (HR) and cell wall strengthening in agave roots. Resistance mechanisms evaluated included pathogenesis-related proteins (PR proteins), phytoanticipins and phytoalexins. For early defense, induced HR was greater with FPA than other strains. Cell wall strengthening was found in agave roots, plants responded differentially to different strains. Initial response to FPA and FOL was similar in PR proteins, phytoalexins and phytoanticipins production. However, the response differentiated with FOL over time, indicating an incompatible interaction. The study identified effective and ineffective defense responses of A. tequilana to Fox infection, where FPA exhibited compatibility and caused unregulated ROS and PCD, early inhibition of PR activity, extensive lignification, and saponin detoxification. In contrast, this study unveiled incompatible interactions (FNPA and FOL) because of limited colonization, localized HR with suppressed ROS, early and sustained POX activation, significant callose accumulation, moderate lignification, and phenol–saponin dynamics that help in tissue containment and recovery. Full article

Fusarium wilt of melon, caused by Fusarium fungi, results in sizeable economic losses worldwide. In Russia, data on the species composition of the causative pathogens of this disease on melon are lacking. From 2022 to 2025, 19 Fusarium isolates from the Volgograd and Rostov regions were included in a study that included species identification using molecular phylogenetic analysis of the tef1 and rpb2 loci, morphological description, and pathogenicity assessment against the host plant and other members of the Cucurbitaceae family. Four Fusarium species were found to be involved in the pathogenesis of Fusarium wilt of melon in Russia: F. clavus (37% of the total number of isolates), F. annulatum (21%), F. cf. inflexum (21%), and F. brachygibbosum (21%). All identified species were isolated in the Volgograd Region, while only F. cf. inflexum and F. brachygibbosum were isolated in the Rostov Region. This study reports for the first time the high pathogenicity of F. cf. inflexum and F. brachygibbosum species associated with melon wilt. Morphological variability and different aggressiveness of isolates of the species F. brachygibbosum and F. clavus, isolated in the Volgograd (-V) and Rostov (-R) regions in different years, were observed. The isolate F. brachygibbosum-V showed high aggressiveness both at the sprout and seedling stages, while the isolate F. brachygibbosum-R was characterized by moderate aggressiveness only at the sprout stage. High pathogenicity of the species isolated from melons was established for other cucurbit crops. F. cf. inflexum was also pathogenic for watermelon and pumpkin, and F. brachygibbosum was pathogenic for pumpkin. The obtained data will have practical value for the development of biological control measures against Fusarium fungi and will be used in a melon breeding program for resistance to Fusarium wilt. Full article

Legumes are sensitive to soil heterogeneity and disease pressure, particularly from Fusarium oxysporum, which causes severe yield losses worldwide. This study examined the relationships between soil properties, disease incidence, and yield variability within management unit zones (MUZs) to support site-specific management strategies. Two field experiments were conducted in central Italy, in two different growing seasons, using synthetic images of bare soil and clusters to delineate MUZs. Soil samples were analyzed for texture, organic carbon, and nitrogen content, while disease incidence and severity were assessed in relation to symptoms on foliar, root, and hypocotyl tissues. Furthermore, pathogen isolations were carried out from the altered hypocotyl and root tissue. Vegetation indices, including NDVI and PRI derived from Sentinel-2 images, were integrated with field observations to map disease and yields spatially. The results highlighted the almost exclusive presence of F. oxysporum on the altered tissues. MUZ-3, characterized by lower organic carbon content and higher sand content, consistently exhibited the highest incidence and severity of Fusarium wilt. In contrast, MUZ-1, richer in clay and organic carbon, supported healthier plant growth and higher productivity. The integration of vegetation indices with field data proved effective in detecting spatial variability, allowing the delimitation of productivity zones and supporting precision farming strategies aimed at mitigating Fusarium-related yield losses. Full article

Banana and plantain crops are essential for food security; Fusarium wilt, caused by Fusarium oxysporum f. sp. cubense (FOC), is one of the most devastating disease affecting these crops worldwide. The pathogen infects the radicular system and subsequently colonizes and collapses the vascular tissue, leading to wilting and plant death. The aims of our study were to determinate the chemical composition of the essential oil from Origanum vulgare obtained by hydro-distillation, and to evaluate its antifungal activity against FOC race 1. GC/MS analysis identified 31 compounds in the oil. Eugenol (76.3%) and D-Limonene (6.13%) were the main components. Antifungal activity was evaluated in vitro and OEO inhibited the mycelial growth of FOC race 1 at 500 µL L⁻¹. The minimum inhibitory concentrations (MIC₅₀ and MIC₉₅) were 111.1 and 174.1 µL L⁻¹, respectively. Fusarium wilt control evaluated in Silk banana vitroplants was analyzed by disease severity in the internal corm, controlled by oregano essential oil at 3000 µL L⁻¹. OEO treatments had no detrimental effects on Silk banana vitroplants. This paper provides knowledge to use oregano-derived compounds to develop bioproducts aimed at the integral and sustainable management of Fusarium wilt in banana and plantain crops. Full article

Modern head cabbage (Brassica oleracea var. capitata L.) breeding is based on the application of molecular markers through marker-assisted selection (MAS). In hybrid breeding, critical markers are deployed to assess cytoplasmic male sterility (CAPS and SSR for orf138), genic male sterility (KASP markers for Ms-cd1, InDel for ms3, and BoCYP704B1), fertility restoration (InDel marker for Rfo), combining ability and genetic diversity (using SSR and KASP marker sets), and to ensure F₁ hybrid seed genetic purity (RAPD and SSR markers sets). Disease resistance, a well-developed category due to frequent monogenic control, includes markers for major pathogens, including those for Fusarium wilt (for Foc-Bo1 gene), black rot (race 1–7 specific SSR and InDel markers), clubroot (Kamogawa, Anno, and Yuki isolates), and downy mildew (BoDMR2 InDel marker). Markers have also been identified for key agronomic and morphological traits, such as those governing petal color (InDel markers for BoCCD4), leaf waxiness (BoGL1, BoGL-3, Cgl1, Cgl2, BoWax1, and BoCER2), and leaf color (ygl-1, BoMYB2, BoMYBL2-1). The review also included markers for resistance to abbioticaly induced negative physiological processes, such as head splitting (QTL SPL-2-1, Bol016058), bolting (resistance loci-associated SSR marker), prolonged flowering time (BoFLC1,2 genes), and high- and low-temperature tolerance (BoTPPI-2, BoCSDP5, BoCCA1). Despite these advancements, the review highlights that the marker repertoire for cabbage remains limited compared with other Brassicaceae species, particularly for complex polygenic traits. This synthesis is a valuable resource for breeders and researchers, facilitating the development of superior head cabbage cultivars and hybrids. Full article

Cowpea Fusarium wilt (CFW) is a soilborne fungal disease caused by Fusarium oxysporum f. sp. tracheiphilum (Fot), leading to substantial yield losses globally. This study evaluates the biocontrol potential of Bacillus velezensis HAB-2 and develops a microbial combination for effective disease management. B. velezensis HAB-2 suppressed F. oxysporum f. sp. tracheiphilum AIQBFO93 growth by 69.8% in vitro and exhibited multiple plant growth-promoting traits. Pot experiments demonstrated that HAB-2 alone achieved a 47.62% control rate against CFW. Furthermore, two compatible plant growth-promoting rhizobacteria (PGPR), Pseudomonas hunanensis HD33 and Enterobacter soli HD42, were isolated from the rhizosphere soil of cowpea previously treated with HAB-2. These two strains were combined with HAB-2 at different concentrations in 15 microbial combinations. The combined application of the three strains provided more consistent disease control, with the optimal combination demonstrating a 15.15% higher control rate than HAB-2 alone. Compared to the untreated control, this combination significantly increased cowpea fresh weight, leaf area, and plant height by 10.60%, 8.04%, and 7.81%, respectively, and upregulated the expression of defense-related genes, indicating enhanced resistance. These results confirm that B. velezensis HAB-2 is an effective biocontrol agent against wilt disease, and its synergistic application with functionally complementary PGPR strains provides a viable strategy for sustainable crop disease management. Full article

Soil-borne diseases of banana severely threaten the sustainable development of the banana industry. In the pineapple–banana rotation system, using rhizosphere microorganisms to control banana Fusarium wilt via pineapple root exudates is a promising green control strategy. However, the role of volatile organic compounds (VOCs) in mediating disease suppression remains unclear. To explore the disease-inhibiting mechanisms, this study employed in vitro assays and high-throughput sequencing to evaluate the effects of three pineapple-root-derived VOCs (decanal, nonanal, octanol). The results showed the following: (1) All three VOCs strongly inhibited the mycelial growth of Fusarium, with octanol exhibiting the highest inhibition. (2) Each VOC promoted Arabidopsis thaliana growth, and decanal was the most effective. (3) In pot experiments, these VOCs significantly altered the banana rhizosphere microbial community, facilitating the colonization of beneficial genera—characterized by reduced microbial diversity and increased beneficial genera abundance. These results delineate a VOC-mediated rhizosphere microbe–Fusarium–plant interaction network, offering a novel theoretical foundation for the ecological control of banana diseases via the rhizosphere microbiome. In conclusion, this study elucidates a new mechanism for banana disease inhibition via VOCs, highlighting the positive impacts on plant growth and rhizosphere soil health through microbiota modulation. Full article

Despite the recognized social and economic importance of common beans (Phaseolus vulgaris L.), the average grain yield is far below the productive potential of cultivars. This situation is explained by several factors, such as the large number of diseases and pests that affect the crop, some of which cause significant damage. It is estimated that approximately 200 diseases can significantly affect common beans. These can be bacterial, viral, fungal, and nematode-induced. The main bean fungal diseases include anthracnose, angular leaf spot, powdery mildew, gray mold, Fusarium wilt, dry root rot, Pythium root rot, southern blight, white mold, charcoal rot and rust. This review provides a comprehensive overview of eleven major fungal diseases affecting common bean, describing their associated damage, characteristic symptomatology, and the epidemiological factors that favor disease development. It further synthesizes current knowledge on host resistance mechanisms that can be exploited to develop molecularly informed resistant genotypes. The compilation includes characterized resistance genes and mapped quantitative trait loci (QTLs), with details on their chromosomal locations, genetic effects, and potential for use in breeding. Moreover, the review highlights successful applications of molecular breeding approaches targeting fungal resistance. Finally, it discusses conclusions and future perspectives for integrating advanced genetic improvement strategies—such as marker-assisted selection, genomic selection, gene editing, and pyramiding—to enhance durable resistance to fungal pathogens in common bean. This work serves as both a reference for forthcoming resistance-mapping studies and a guide for the strategic selection of resistance loci in breeding programs aimed at developing cultivars with stable and long-lasting fungal resistance. Full article

Fusarium wilt, caused by Fusarium oxysporum f. sp. phaseoli (Fop), is a major constraint to global common bean (Phaseolus vulgaris L.) production. Thiamine (vitamin B1), an essential coenzyme in plant metabolism, has recently emerged as a potential regulatory factor in plant defense. Here, we performed a comprehensive genome-wide analysis of thiamine biosynthesis-related genes in common bean and elucidated their roles in resistance to Fusarium wilt. Five key thiamine biosynthetic genes were identified and characterized, showing conserved functional domains and evolutionary conservation across species. Expression profiling revealed tissue-specific patterns, with PvTHI1-1 and PvTHIC being highly expressed in reproductive and photosynthetic organs, with their relative expression levels 0.28–0.57 higher than other members in the same tissue, while PvTPK maintained a basal expression level in the roots. Upon Fop infection, resistant genotypes exhibited significantly higher expression of thiamine biosynthetic genes and greater accumulation of endogenous thiamine and its derivatives than susceptible ones. Functional analysis using Agrobacterium rhizogenes-mediated transformation demonstrated that overexpression of PvTPK enhanced thiamine metabolism and conferred resistance in susceptible genotypes. Similarly, exogenous application of thiamine upregulated biosynthetic genes and improved disease resistance. Together, these results reveal that thiamine biosynthesis is intricately linked to Fusarium wilt resistance and that both genetic and biochemical manipulation of thiamine pathways can enhance disease tolerance. This study provides new insights into thiamine-mediated plant immunity and establishes a foundation for its application in the control of Fusarium wilt in common bean. Full article

Fusarium wilt disease, caused by Fusarium oxysporum f. sp. cucumerinum (FOC), leads to widespread yield losses and quality deterioration in cucumber. Endophytes, as environmentally friendly control agents that enhance pathogen resistance in their host plants, may mitigate these problems. In this study, we isolated 14 endophytic bacteria from invasive Ambrosia artemisiifolia and screened the strain Bacillus subtilis TCX1, which exhibited significant antagonistic activity against FOC (inhibitory rate of 86.0%). TCX1 killed Fusarium oxysporum by being highly likely to produce lipopeptide and producing wall hydrolytic enzymes including protease, cellulase, and β-glucanase, thereby inhibiting mycelial growth and spore germination and causing peroxidation of FOC’s cytoplasmic membrane. In addition to its direct effects, TCX1 exerts indirect effects by inducing cucumber resistance to FOC. When cucumber seedlings were inoculated with TCX1, antioxidant enzymes related to disease resistance, including Superoxide dismutase (SOD), Peroxidase (POD), Polyphenol oxidase (PPO) and Phenylalanine ammonialyase (PAL) in cucumber, were significantly increased. The marker genes involved in induced systemic resistance and the salicylic acid signaling pathway, such as npr1, pr1a, pr2, pr9, lox1, and ctr1, were also dramatically upregulated, indicating these pathways played an important role in improving cucumber resistance. Notably, TCX1 can also promote cucumber growth through producing indole-3-acetic acid, solubilizing phosphate, and secreting siderophores. Given that TCX1 has dual functions as both a biological control agent and a biofertilizer, it offers an effective strategy for managing cucumber seedling blight while enhancing plant productivity. Full article

Background/Objectives: Fusarium wilt of cotton, caused by Fusarium oxysporum f. sp. vasinfectum (FOV), is a destructive vascular disease that severely impacts cotton production. Among its variants, race 4 (FOV4) is especially aggressive, leading to early season stand losses and yield reductions. While resistant cultivars of Gossypium barbadense (pima cotton) have been developed, the molecular basis of this resistance remains unclear. This study aimed to characterize transcriptomic responses associated with FOV4 resistance in pima cotton. Methods: We conducted an in vitro infection assay using two G. barbadense cultivars with contrasting phenotypes: the highly resistant ‘DP348RF’ and the highly susceptible ‘GB1031’. Root tissues were sampled at multiple stages of infection, and RNA sequencing was performed to identify differentially expressed genes and pathways contributing to resistance. Results: Resistant plants ‘DP348RF’ showed strong induction of genes related to reactive oxygen species (ROS) metabolism, chitinase activity, and lignification compared to the susceptible cultivar. Notably, genes involved in the biosynthesis and reinforcement of the Casparian strip, a critical biochemical barrier limiting pathogen penetration into vascular tissues, were uniquely and significantly upregulated in resistant roots. These transcriptional responses suggest that fortification of cell wall barriers and enhanced antimicrobial defenses contribute to effective restriction of FOV4 colonization. Conclusions: Our findings identify a distinct molecular signature of resistance to FOV4 in pima cotton, with Casparian strip reinforcement emerging as a potential mechanism limiting vascular infection. These insights provide a foundation for breeding strategies aimed at improving Fusarium wilt resistance in cotton. Full article