Search Results (354)

G. barbadense represents an indispensable germplasm resource for high-quality textile fiber and disease resistance; nevertheless, systematic information regarding its ZRT/IRT-like protein (ZIP) gene family remains limited. Here, a total of 46 GbZIP genes were identified across the G. barbadense genome. Comprehensive bioinformatic investigations revealed uneven chromosomal distribution and confirmed that segmental/whole-genome duplications, supplemented by localized tandem duplications, drove family expansion. Members clustered within the same phylogenetic clades shared conserved motif organization and gene architecture, while promoter regions harbored abundant cis-acting elements associated with phytohormone and stress signaling. Transcriptome profiling indicated distinct expression patterns across vegetative/reproductive tissues, fiber and ovule developmental stages, and diverse abiotic stress conditions (cold, hot, drought, and salt). Quantitative Real-Time PCR (qRT-PCR) further validated that several GbZIP candidates exhibited temporal expression variations upon exposure to cadmium toxicity, V. dahliae infection, and combined Cd-V. dahliae stress. Specifically, GbZIP13, GbZIP18, GbZIP27, and GbZIP36 displayed prominent broad-spectrum responses to all three stress conditions, whereas GbZIP16, GbZIP29, and GbZIP30 showed stress-specific regulatory divergence. Overall, this study aims to systematically analyze the evolutionary characteristics and expression patterns of the GbZIP family, and to specifically evaluate the response differences under Cd stress, V. dahliae stress, and combined stress, in order to identify potential key candidate genes. Full article

Verticillium wilt, caused by Verticillium dahliae, is a major constraint on cotton production. The GASA (Gibberellic Acid-Stimulated in Arabidopsis) proteins are cysteine-rich peptides induced by gibberellin signaling; however, their systemic role in upland cotton (Gossypium hirsutum) resistance to Verticillium wilt remains elusive. Here, we identified 40 GhGASA members from the G. hirsutum genome, which were clustered into three subfamilies. All members possessed a typical gibberellin-regulated domain, and segmental duplication was the primary driver of family expansion. Transcriptomic analyses revealed tissue-specific expression, with high abundance in pistils and roots, and distinct responsive patterns to salt, drought, and cold stresses. Quantitative real-time PCR (qRT-PCR) showed that multiple GhGASA genes were significantly upregulated following V. dahliae inoculation, with transcript levels being much higher in roots and stems than in leaves. Notably, GhGASA17, harboring ethylene-responsive elements, was identified as a key candidate involved in the defense response. Overall, this study provides a comprehensive characterization of the GhGASA gene family, offering a theoretical foundation for understanding its regulatory functions in Verticillium wilt resistance and delivering potential genetic resources for molecular breeding in cotton. Full article

Protein arginine methyltransferases (PRMTs) are key regulators of diverse cellular processes in eukaryotes, including transcriptional regulation, RNA processing, signal transduction and DNA repair. However, the biological functions of PRMTs in Verticillium dahliae remain largely unexplored. In this study, we identified a PRMT1 homolog in V. dahliae. Targeted deletion of VdPRMT1 resulted in severely impaired hyphal growth, sporulation, stress responses and pathogenicity. Subcellular localization analysis showed that VdPRMT1 is distributed in both the nucleus and cytoplasm of hyphae. Host-induced gene silencing (HIGS) of VdPRMT1 in cotton significantly reduced disease severity, supporting its important role in pathogenicity. Furthermore, VdLuc7, a U1 snRNP-associated protein containing multiple RG/RGG motifs, was identified as a putative interacting partner of VdPRMT1 through yeast two-hybrid (Y2H) screening, bimolecular fluorescence complementation (BiFC) and luciferase complementation imaging (LCI) assays. Together, our results demonstrate that VdPRMT1 is required for normal fungal development and full virulence in V. dahliae, and suggest that arginine methylation may contribute to pathogenicity through regulation of RNA processing-related pathways. These findings provide new insights into the molecular mechanisms underlying fungal virulence and identify VdPRMT1 as a potential target for disease control. Full article

Eggplant (Solanum melongena L.) is an important solanaceous vegetable crop cultivated worldwide. Verticillium wilt, caused by Verticillium dahliae, severely restricts eggplant growth and yield, while most cultivated eggplant varieties show only limited resistance to this disease. In contrast, Solanum torvum, a wild relative of eggplant, exhibits strong natural resistance to Verticillium wilt. The molecular mechanisms underlying the contrasting responses of cultivated eggplant and S. torvum to V. dahliae infection remain poorly understood. In this study, high-throughput iTRAQ-based quantitative proteomics was used to analyze root protein profiles of S. torvum after V. dahliae inoculation. A differentially expressed protein, StoAOS1, was identified in S. torvum and was strongly induced by V. dahliae infection. StoAOS1 encodes a key enzyme in the jasmonic acid (JA) biosynthetic pathway. Further analysis showed that exogenous methyl jasmonate (MeJA) treatment markedly induced StoAOS1 expression. Virus-induced gene silencing of StoAOS1 significantly compromised Verticillium wilt resistance in S. torvum, accompanied by reduced acid-insoluble lignin accumulation and decreased transcript levels of the defense-related marker genes StoPDF1.2, StoVSP2, and StoThi2.1. Conversely, transient overexpression of StoAOS1 in Nicotiana benthamiana enhanced resistance to V. dahliae. Together, these findings suggest that StoAOS1 positively regulates Verticillium wilt resistance in S. torvum, likely through a JA-dependent defense pathway. Full article

Cotton is an economically important cash crop severely affected by Verticillium wilt caused by Verticillium dahliae. Secreted cell-wall-degrading enzymes act as key virulence factors of this pathogen, yet the biological function of glucan 1,3-β-glucosidase remains largely uncharacterized. The gene VDAG_02814 (designated Vdbgl1) was previously found to be strongly induced during host infection. Here, combined approaches including gene knockout, host-induced gene silencing (HIGS), and transcriptomic analysis were utilized to characterize the function of Vdbgl1. The results showed that Vdbgl1 deletion retarded colony growth on PDA medium by 20.1–21.6%, decreased conidial yield by 20.2–46.7%, lowered spore germination rate by 30.7–32.9%, and weakened utilization of diverse carbon sources by 5.0–14.9%. The ΔVdbgl1 mutants also exhibited significantly increased sensitivity to cell wall-perturbing, osmotic, and membrane-damaging agents. Additionally, the ΔVdbgl1 mutants exhibited reduced disease index by approximately 19.1–27.7% and decreased fungal biomass by 42.7–61.8% in cotton; consistently, HIGS-mediated silencing of Vdbgl1 reduced the disease index by 25.7% and 26.7% and decreased fungal biomass by 48.1–71.5%. Transcriptome profiling of cotton roots infected by the ΔVdbgl1 mutant and the wild-type strain revealed 1007 down-regulated genes enriched in carbohydrate metabolism, cell wall degradation, and energy pathways, including 27 carbohydrate-active enzyme genes and 58 genes encoding cysteine-rich secreted proteins. Collectively, these findings indicated that Vdbgl1 coordinates carbon utilization, cell wall remodeling, and stress responses to regulate fungal development and pathogenicity, representing a promising target for cotton Verticillium wilt control. Full article

Verticillium dahliae is a devastating soil-borne fungal pathogen that causes severe yield losses in melon (Cucumis melo L.) and other crops. Identifying novel resistance genes is crucial for sustainable disease management. In this study, we characterized the function of CmVQ23, a candidate gene previously identified through QTL mapping, in mediating defense against V. dahliae using heterologous expression in Arabidopsis thaliana. Subcellular localization assays revealed that the CmVQ23-eGFP fusion protein predominantly localized to the nucleus, consistent with its predicted role as a co-factor of transcription factor. Upon V. dahliae inoculation, CmVQ23-overexpressing Arabidopsis lines exhibited significantly reduced disease indices and restricted fungal proliferation compared with wild-type and mutant plants, although these lines displayed altered vegetative growth, including delayed bolting and reduced plant height. Mechanistically, CmVQ23 overexpression promoted reactive oxygen species (ROS) accumulation and hypersensitive response (HR)-mediated cell death at infection sites, as evidenced by intensified DAB and trypan blue staining. Furthermore, transgenic lines maintained higher photosynthetic efficiency, enhanced antioxidant enzyme activities, and increased lignin deposition via upregulation of phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO). Notably, CmVQ23 overexpression markedly upregulated both salicylic acid (SA)- and jasmonic acid/ethylene (JA/ET)-responsive marker genes, including AtPR1, AtPR2, AtPR5, AtPAD4, AtPDF1.2, and AtVSP2 upon infection. Collectively, these findings demonstrate that CmVQ23 functions as a positive regulator of resistance to Verticillium dahliae by orchestrating ROS/HR-mediated cell death, antioxidant defense, phenylpropanoid pathway activation, and phytohormone signaling crosstalk, offering a promising genetic resource for improving Verticillium wilt resistance in crops. Full article

Cotton Verticillium wilt is a devastating fungal disease caused by Verticillium dahliae, and biological control has become a safe and efficient strategy for its green prevention and control. In this study, the endophytic strain Bacillus velezensis BHZ-29 was used as the biocontrol material, and rifampicin labeling and greenhouse pot assays were performed to clarify its colonization characteristics and induced disease resistance mechanism in cotton. The results showed that the rifampicin-resistant mutant strain maintained consistent morphological traits, antagonistic activity and biocontrol performance with the wild-type strain, ensuring the reliability of colonization tracing. Strain BHZ-29 could stably colonize the roots, stems and leaves of different cotton varieties, with roots serving as the dominant colonization tissue. Physiological analysis indicated that BHZ-29 inoculation significantly activated the antioxidant and defense enzyme system of cotton, including POD, CAT, SOD, PPO and PAL. The defense enzyme activities of cotton leaves showed a trend of first increasing and then decreasing, and the combined inoculation of BHZ-29 and V. dahliae exhibited the highest enzyme activity. Meanwhile, BHZ-29 treatment significantly increased vitamin C content and reduced malondialdehyde accumulation in cotton, alleviating pathogen-induced oxidative damage. Field pot verification confirmed that BHZ-29 possessed excellent and broad-spectrum biocontrol effects on cotton Verticillium wilt with stable control efficacy across different cotton varieties. This study clarifies the colonization and induced resistance mechanism of strain BHZ-29 against Verticillium wilt, providing a promising microbial resource and theoretical basis for the green biological control of cotton soil-borne diseases. Full article

Cotton verticillium wilt caused by Verticillium dahliae severely restricts global cotton production. Mycovirus–induced hypovirulence provides a promising strategy for sustainable disease management. In this study, V. dahliae isolates from Xinjiang were screened by virome sequencing and RT–PCR, and strain 121–11C–1 co–infected with Verticillium dahliae partitivirus 1 (VdPV1) and Verticillium dahliae magoulivirus 1 (VdMoV1) was identified. Virus–free isogenic strains were obtained via single–conidium purification, verifying that both viruses can be vertically transmitted through fungal conidia. Dual–culture assays uncovered a novel, previously unreported horizontal transmission dependency between the two viruses: VdPV1 achieves horizontal transmission only with the assistance of VdMoV1, whereas VdMoV1 can transmit independently or co–transmit with VdPV1. Biological and pathogenicity assays demonstrated that both viruses significantly inhibit mycelial growth, reduce conidial production and attenuate fungal virulence. Notably, dual infection induced a significantly stronger hypovirulent phenotype than single infection. These findings elucidate the transmission dynamics of VdPV1 and VdMoV1, expand the repertoire of hypovirulent mycoviruses in V. dahliae, and provide evidence that viral co–infection enhances fungal attenuation, offering potential applications for biological control of cotton Verticillium wilt. Full article

The DUF538 gene family, harboring unknown functional proteins, has been reported to take active roles in plant development and response to adversities, while few studies of genome-wide identification and functional verification have been performed in cotton. Hence, two ancestral diploid species, G. arboretum and G. raimondii, and two cultivated tetraploid ones, G. hirsutum and G. barbadense, were chosen in this study to investigate the cotton DUF538 gene family, resulting in 37, 37, 70, and 70 members identified, respectively. A phylogenetic tree was constructed on these cotton DUF538 genes, together with 22 A. thaliana ones, which were divided into seven groups unevenly distributed across nearly all chromosomes. High-degree conservatism, while rich in diversity, was separately observed in gene structure and conserved motif analyses between the same groups and different groups, and a great number of gene-replication events were detected from intraspecific and interspecific collinearity analyses, implying this was the driving force for DUF538 family expansion. Multiple cis-acting elements relevant to adversity-stress responses were found in the promoter region, which were consistent with the transcriptome expression analyses in response to low-temperature and drought stress and Verticillium wilt infection. Coincidentally, GhDUF538-7 showed the core position in the protein–protein interaction network and was identified in the overlapping region of the interval of four reported VW resistance-related QTLs. The gene function of GhDUF538-7 was verified via gene cloning, relative expression-pattern detection, and virus-induced gene silencing (VIGS) experiment. The TRV:DUF538-7 plants showed more serious VW symptoms, significantly severe disease indices, relatively higher fungal biomass, and increased brown vascular bundles compared with TRV:00 plants. Significantly lower expression levels of marker genes PR4 and MYC2 in jasmonate signaling pathways indicated GhDUF538-7 as a potentially positive regulatory factor in plant defense via hormone signal transduction. This study not only broadened the research perspective of evolution and functional differentiation of the cotton DUF538 gene family, but it also revealed the cooperative relationship between DUF538-7 and the JA pathway for further molecular mechanisms of cotton resistance to VW infection. Full article

Alfalfa Verticillium wilt, caused by Verticillium alfalfae, is a globally significant disease with increasing incidence and expanding epidemic areas. This study surveyed six major alfalfa-producing regions in Inner Mongolia, China—Chifeng, Tongliao, Ulanqab, Ordos, Bayannur, and Hohhot—and successfully isolated V. alfalfae exclusively from samples collected in Hohhot and Bayannur. Based on morphological characterization, multi-locus phylogenetic analysis (act, tef1-α, gapdh, and ts genes), and pathogenicity tests fulfilling Koch’s postulates, all 33 isolates were consistently identified as V. alfalfae, with disease severity levels ranging from 3.04 to 4.79 on the susceptible cultivar Zhongmu No. 1. As a preliminary assessment, the in vitro sensitivity of a representative strain, Va8, to eight commercial fungicides was evaluated using the mycelial growth inhibition method. Among the tested fungicides, 30% difenoconazole–propiconazole exhibited the strongest inhibitory effect (EC₅₀ = 0.14 μg/mL), followed by 10% trifloxystrobin & 20% tebuconazole (EC₅₀ = 0.20 μg/mL). However, given the substantial virulence variation observed among isolates, these sensitivity data should be interpreted with caution, as population-level differences may exist. These findings represent the first confirmed report of V. alfalfae in Inner Mongolia and provide a preliminary yet critical reference for prioritizing candidate fungicides for future multi-isolate and field evaluations. Full article

The use of natural products as alternatives to synthetic fungicides has gained increasing importance in crop protection. Among these, clove (Syzygium aromaticum) and its active compound, eugenol, are well known for their antifungal properties. However, it remains unclear whether the antifungal activity of clove is primarily driven by its major constituent, eugenol, or whether the whole essential oil exhibits greater or synergistic efficacy. Addressing this question is crucial for optimizing their application as biofungicidal agents; The chemical composition of clove essential oil was characterized using gas chromatography–flame ionization detection (GC-FID) and gas chromatography–mass spectrometry(GC-MS). The antifungal activity of the essential oil and pure eugenol (300 µg/mL) was evaluated in vitro against Botryotinia fuckeliana, Rhizoctonia solani, and Verticillium dahliae on potato dextrose agar (PDA). Mycelial growth inhibition was quantified, and data were analyzed using two-way analysis of variance (ANOVA) followed by Tukey’s honestly significant difference (HSD) test (α = 0.05); Eugenol exhibited higher antifungal activity than the essential oil across all tested species. V. dahliae was completely inhibited (100%) by eugenol, while the essential oil showed lower efficacy. Despite the high eugenol content (87.3%) in the oil, its reduced activity suggests that minor constituents may modulate overall antifungal performance. These findings demonstrate that eugenol is more effective than clove essential oil as an antifungal agent. This highlights that the biological activity of clove is largely driven by its major active component, providing key insights for the development of more efficient biofungicidal strategies. Full article

Verticillium wilt of hop (Humulus lupulus L.), caused by the soil-borne pathogen Verticillium nonalfalfae, is a devastating disease with no effective chemical control. In European hop-growing regions, breeding resistant cultivars is the most effective strategy. The lack of response differences in earlier studies suggests constitutive resistance. We therefore conducted a genome-wide association study (GWAS) using a phased hop genome assembly to improve detection of Verticillium resistance loci. A bi-parental population of 142 genotypes, derived from a cross between resistant Wye Target and susceptible BL2/1, was phenotyped for Verticillium wilt resistance and genotyped by sequencing. Association analyses with five statistical models (MLM in TASSEL 5, MLM, MLMM, FarmCPU and BLINK in GAPIT) did not identify any significant SNPs; however, several candidate loci were identified using exploratory threshold, particularly in the phase 2 genome assembly, including a wall-associated kinase (WAK) consistently detected across both genome phases and all models. GWAS results were further assessed with a Random Forest model, which identified SNPs of high feature importance and showed adequate predictive power (accuracy ≈ 0.4, correlation ≈ 0.8) for preliminary breeding screening. These findings provide an initial set of candidate markers and exploratory prediction models for Verticillium wilt resistance in hop, representing a valuable genomic resource for future marker-assisted selection and breeding strategies. Full article

Verticillium wilt caused by Verticillium dahliae poses a severe threat to pepper (Capsicum annuum) production worldwide. Kunitz trypsin inhibitors (KTIs) play crucial roles in plant disease resistance, yet research on the CaKTI gene family in pepper, especially regarding its regulatory functions in resistance to V. dahliae, remains limited. In this study, members of the CaKTI gene family were systematically identified in the pepper genome, followed by comprehensive analyses of their physicochemical properties, phylogeny, chromosomal localization, conserved motifs, cis-acting elements in promoters, and expression profiles. A total of 22 CaKTI genes were identified, all harboring the beta-trefoil_STI superfamily domain. They were unevenly distributed across four chromosomes, with evident tandem duplication events, and exhibited tissue-specific and developmental stage-specific expression patterns. In the Verticillium-resistant pepper cultivar, five candidate CaKTI genes (CaKTI9, CaKTI6, CaKTI17, CaKTI18, and CaKTI22) were significantly induced and upregulated, particularly in roots, and their expression might be modulated by the methyl jasmonate signaling pathway. This study reveals the molecular features, evolutionary conservation, and defense-associated expression patterns of CaKTI genes in pepper and provides a preliminary exploratory basis for future research on disease resistance and molecular breeding. Full article