Search Results (54)

Strawberry crown rot (SCR) disease poses a significant threat to strawberry production in Zhejiang Province, China. In our previous study, we identified Colletotrichum siamense strain JDA-12 as the dominant causal agent of SCR disease in samples collected from Zhejiang. However, the factors associated with this phenomenon remain unclear. In this study, a comparative analysis of JDA-12 and other documented Colletotrichum species revealed that the gene families AbiEii and CBM24-GH71, together with two annotated RiPP-like secondary metabolite biosynthetic clusters, are specifically expanded or uniquely present in JDA-12. These lineage-specific genomic features may represent genomic signatures associated with ecological adaptation and host-associated interactions of JDA-12. Additionally, we assessed the pathogenicity of JDA-12 on major strawberry cultivars grown in Zhejiang. The findings demonstrated that ‘Benihoppe’ exhibited high susceptibility, while ‘Fenyu No.1′ showed comparatively strong resistance. Furthermore, we evaluated the impact of environmental factors on pathogenicity and found that short-day conditions (10L:14D), high temperature (~30 °C), and high humidity (≥90%) constitute the optimal environment for JDA-12 infection in strawberries, at least under conditions representative of Zhejiang. This study provides genomic insights into the ecological adaptation and pathogenic potential of JDA-12, while revealing environmental conditions favorable for SCR development, facilitating the development of effective disease management strategies. Full article

Ipê trees (Bignoniaceae), mainly belonging to the genus Handroanthus, are widely used in urban landscaping and reforestation programs in Brazil. Anthracnose, typically associated with species of Colletotrichum, represents one of the major diseases affecting ipê seedlings and ornamental trees. However, the etiological agents involved have not yet been fully clarified using modern phylogenetic tools. In this study, we identified Colletotrichum species associated with anthracnose in ipê trees from Pernambuco, Brazil. A total of 22 isolates were obtained from symptomatic leaves of Handroanthus impetiginosus and H. chrysotrichus. Species identification was based on multilocus phylogenetic analyses using CAL, GAPDH, GS, and TUB2 loci. The isolates were assigned to three species: Colletotrichum siamense, C. tropicale, and C. karsti. Colletotrichum siamense was the most prevalent species (50%), followed by C. tropicale (36.3%), while C. karsti represented 13.7% of the isolates. Pathogenicity tests confirmed that all isolates were pathogenic to both ipê species, producing typical anthracnose symptoms. Aggressiveness differed between hosts, with H. impetiginosus showing higher susceptibility, as indicated by larger lesion development, whereas H. chrysotrichus exhibited lower disease aggressiveness. Thus, our findings represent the first multilocus-based identification of Colletotrichum species causing anthracnose in ipê trees, providing new insights into the diversity and epidemiology of this disease in urban environments. Full article

Anthracnose, caused by Colletotrichum siamense, is a major limiting factor for global natural rubber production. To develop sustainable control strategies, seven bacterial strains with antagonistic activity against C. siamense were isolated from healthy rubber tree leaves, with strain WR7 demonstrating the most significant antifungal effect, exhibiting an inhibition rate of 82.36%. Pot experiments revealed that WR7 achieved a disease control efficacy of 71.65% against C. siamense-induced anthracnose. Genomic analysis identified WR7 as Bacillus altitudinis. This strain inhibits pathogen growth through multiple mechanisms, including disruption of the pathogen’s cell wall and membrane integrity, induction of reactive oxygen species accumulation in hyphae, and secretion of cellulase, glucanase, protease, and siderophores. Gene cluster analysis further confirmed the potential of WR7 to synthesize antagonistic secondary metabolites such as lichenysin, fengycin, and bacilysin, while its sterile filtrate and volatile compounds also exhibited significant antifungal activity. Moreover, treatment with WR7 activated defense-related enzymes, including catalase and superoxide dismutase in rubber tree leaves, thereby enhancing the plant’s defense responses. This study is the first to report that Bacillus altitudinis WR7 has potential as a biocontrol agent for managing rubber tree anthracnose, offering a novel resource for sustainable disease management in rubber production. Full article

Cornus officinalis is a valuable traditional Chinese medicinal (TCM) plant species with both therapeutic and ornamental attributes. It is widely used in TCM prescriptions to nourish the liver and kidneys and constitutes a critical component of numerous classical formulas. In recent years, the large-scale cultivation of this medicinal plant has been expanded in Xixia County, Henan Province, China. Field investigations have revealed widespread brown leaf spot, accompanied by reductions in yield and quality. In this study, symptomatic leaves were collected for pathogen isolation. Tissue isolations consistently yielded a Colletotrichum fungus, and morphology combined with multi-locus phylogenetic analyses (the internal transcribed spacer, glyceraldehyde-3-phosphate dehydrogenase, chitin synthase, actin, and β-tubulin) identified the pathogen as Colletotrichum siamense. Pathogenicity assays (conducted by either wounding and inoculating detached leaves with a mycelium plug or spraying a conidium suspension on healthy potted plants) reproduced field symptoms, and the pathogen was re-isolated, thereby fulfilling Koch’s postulates. In vitro fungicide assays showed that carbendazim, tebuconazole, and prochloraz were highly effective against the pathogen, providing preliminary information for chemical management. This is the first documentation of C. siamense causing leaf anthracnose on C. officinalis and provides a basis for developing targeted control strategies to mitigate disease impacts and preserve yield and quality. Full article

Strawberry anthracnose caused by Colletotrichum siamense threatens global strawberry production. Traditional chemical control faces environmental and safety challenges, making resistant cultivar development critical for sustainability. This study aimed to rank 10 cultivars’ resistance to C. siamense Cs.4J and clarify temporal redox and transcriptomic drivers of resistance. We evaluated resistance using the disease index (DI), observed oxidative stress indicators [peroxidase (POD), hydrogen peroxide (H₂O₂), malondialdehyde (MDA), catalase (CAT)], and conducted Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and weighted gene coexpression network analysis (WGCNA). Significant resistance differences emerged: ‘Tianxianzui’ (TXZ) was resistant (DI 10.0–20.0%), while ‘Miaoxiang7’ (MX7) was highly susceptible (DI > 50%). ‘MX7’ showed sustained POD overactivation, progressive H₂O₂ accumulation, and high MDA (severe oxidative damage); ‘TXZ’ maintained redox balance via earlier CAT activation. KEGG identified 5 key pathways (e.g., phenylpropanoid biosynthesis), and Weighted Gene Co-expression Network Analysis (WGCNA) revealed 2 core modules (resistance-related red, susceptibility-related brown) plus 2 hub genes (FvRNF144B-like [Fragaria vesca RING Finger Protein 144B-like], FaPHR1-like [Fragaria × ananassa PHR1-like]). ‘TXZ’ and ‘MX7’ represent resistant/susceptible cultivars; early CAT activation for redox balance is a key resistance trait. The 5 pathways and 2 hub genes provide a theoretical basis for future functional validation and exploring strawberry–C. siamense interaction mechanisms. Full article

This study conducted a systematic investigation and identification of pathogenic fungi associated with anthracnose symptoms on economically important plants across multiple provinces in China (Beijing, Fujian, Guangdong, Guizhou, and Shaanxi). Through multi-locus phylogenetic analysis (ITS, gapdh, chs-1, act, tub2, his3, and cal) and morphological characterization of 67 strains, a total of 16 Colletotrichum species were identified, belonging to six species complexes (C. acutatum, C. boninense, C. destructivum, C. gloeosporioides, C. orchidearum, and C. spaethianum). Among these, four novel species were described: Colletotrichum aquilariae, C. crataegi, C. dongguanense, and C. flavosporum. The study also confirmed 12 known species: C. boninense, C. fioriniae, C. fructicola, C. godetiae (with C. americanum proposed as its synonym), C. gloeosporioides (with C. juglandicola, C. juglandium, and C. peakense proposed as its synonyms), C. karsti, C. nymphaeae, C. orchidearum (with C. subplurivorum proposed as its synonym), C. plurivorum, C. siamense, C. sojae, and C. spaethianum. The research revealed significant pathogen species diversity, distinct geographical distribution patterns (greatest diversity in Beijing, novel species primarily from Guangdong), and host preferences (e.g., C. gloeosporioides was the most widely distributed and dominant species on walnut). Furthermore, ten new host records were reported. The study explored correlations between pathogens and their hosts, particularly walnut, providing a crucial foundation for understanding the pathogen composition and ecology of anthracnose diseases affecting plants in China. Full article

Anthracnose is one of the main diseases of mango, which seriously affects the yield and quality. Previous studies found that mango anthracnose in China involves at least 13 species of Colletotrichum. From mango with anthracnose symptoms samples, we previously obtained 134 strains from 13 species, and 26.0% were C. fructicola, while 27.6% were C. siamense, and 31.3% were C. asianum, with a few specimens for each of the remaining species. These three main species were used in intraspecific mating tests to assess sexual reproduction. The intraspecific mating tests revealed that C. fructicola and C. siamense readily produced ascospores, while C. asianum did not. From the 595 intraspecific crosses with 35 isolates of C. fructicola, 34 crosses were considered fertile. Among these, thirty single-ascospore isolates were chosen for pathogenicity testing and genetic variation analysis (ITS and ApMat loci). The results revealed that some progeny showed higher aggressiveness than their parents, while some progeny showed lower aggressiveness. Future tests are needed to assess the genetic basis of these aggressiveness differences. The results provide a scientific basis for further research on sexual reproduction and pathogenicity of Colletotrichum, which may allow for comprehensive disease prevention and control. Full article

Colletotrichum spp. are the causative agents of anthracnose of rubber trees, one of the most destructive diseases, resulting in substantial economic losses. To investigate the evolutionary characteristics of these pathogenic species, we first assembled the complete mitogenomes of four dominant pathogens, i.e., C. siamense, C. fructicola, C. wanningense and C. bannaense. Comparative analyses revealed that variations in their mitogenome size were primarily driven by intron expansion and expansion/contraction within the cox1, cob and nad genes. Moreover, we observed the strong conservation of gene content, mitochondrial DNA copy number, gene order and intron features within species complexes, but a clear divergence between them. Notably, further studies indicated that patterns such as genomic organization, selective pressures and codon usage were consistent across the genus, suggesting that Colletotrichum species complexes had followed distinct evolutionary trajectories, particularly in the arrangement of protein-coding genes. Therefore, this study systematically characterized the mitogenomes of the four major Colletotrichum species associated with rubber tree anthracnose and provided novel insights into the broad evolutionary mechanisms shaping Colletotrichum species complexes. Full article

Walnut anthracnose (Colletotrichum gloeosporioides and C. siamense) and brown spot (Alternaria alternata) cause severe yield losses globally. Conventional fungicides face the challenges of pathogen resistance and environmental toxicity. This study evaluates 4-propylphenol, a plant-derived phenolic compound, as an eco-friendly alternative against key fungal pathogens of walnut. In vitro assays determined EC₅₀ values against target pathogens (29.11–31.89 mg·L⁻¹) via mycelial growth inhibition and conidial germination suppression (EC₅₀ = 55.04–71.85 mg·L⁻¹). Mechanistic analyses confirmed membrane disruption through propidium iodide staining (9.5-to-14.0-fold fluorescence intensity increase), DNA leakage (77.82–85.15% at 250 mg·L⁻¹), and protein efflux (58.10–66.49%). In field trials, we implemented a phenology-driven strategy: 100 mg·L⁻¹ ground/canopy spray at flowering to reduce primary inoculum, followed by 400 mg·L⁻¹ canopy application at fruiting. This protocol achieved 86.67% control efficacy against disease complexes with negligible phytotoxicity (SPAD variation < 5%). 4-propylphenol provides a sustainable solution through membrane-targeting action, effectively overcoming fungicide resistance in woody crops. Full article

Culinary melon (Cucumis melo subsp. agrestis var. conomon) is widely cultivated throughout Thailand and represents an important agricultural crop. During 2023–2024, anthracnose, charcoal rot, and fruit rot caused by fungi were observed on postharvest culinary melon fruits in northern Thailand. This study aimed to isolate and identify fungal pathogens associated with these postharvest diseases in culinary melons, as well as to assess their pathogenicity. Eight fungal strains were isolated and identified through morphological characterization and multi-gene phylogenetic analysis. Colletotrichum chlorophyti and C. siamense were identified as the causal agents of anthracnose, Fusarium sulawesiense caused fruit rot, and Macrophomina phaseolina was responsible for charcoal rot. Pathogenicity tests were conducted, and the fungi were successfully re-isolated from the symptomatic lesions. Moreover, sensitivity tests for fungicides revealed that C. siamense was completely inhibited by copper oxychloride and copper hydroxide. Colletotrichum chlorophyti was inhibited by benalaxyl-M + mancozeb, copper hydroxide, and mancozeb. In the case of M. phaseolina, complete inhibition was observed with the use of benalaxyl-M + mancozeb, mancozeb, and propineb. Copper hydroxide successfully inhibited F. sulawesiense completely. To our knowledge, this study is the first to report C. siamense and C. chlorophyti as causes of anthracnose, F. sulawesiense as a cause of fruit rot, and M. phaseolina as a cause of charcoal rot in postharvest culinary melon fruits in Thailand. It also marks the first global report of C. siamense, M. phaseolina, and F. sulawesiense as causal agents of these respective diseases in culinary melon. Furthermore, the results of the fungicide sensitivity tests provide valuable information for developing effective management strategies to control these postharvest diseases in the future. Full article

Anthracnose is a disease caused by phytopathogenic fungi such as Colletotrichum siamense that attacks plants and fruits causing great postharvest losses. Different alternatives for the control of this fungus have been studied. In the present study, we evaluated the in vitro antifungal activity of the methanolic extracts of Baccharis glutinosa (ExB) and Jacquinia macrocarpa (ExJ) individually, as well as in combination with chitosan (CS), along with their toxicity in different models. Using the radial growth technique, it was observed that the mycelial development of C. siamense was altered and reduced during exposure to the different treatments evaluated during the first hours of incubation, indicating a fungistatic effect. While the cell viability, by colorimetric assay using the XTT salt, showed alteration since the chitosan reduced proliferation by 50%, while the plant extracts and their mixtures with chitosan reduced approximately 40% indicating cell damage, which was confirmed by fluorescence microscopy. In addition, toxicity tests demonstrated that the J. macrocarpa extract significantly affected the germination percentage of Lactuca sativa seeds, whereas radicle length was reduced in all treatments except for chitosan. The larval survival test for Artemia salina with the extracts indicated their potential toxicity by causing up to 60% mortality. The results indicate that ExB and ExJ mixed with CS are a good option for controlling C. siamense; however, at the concentrations used, they exhibit a toxic effect on the evaluated models. Full article

This study aimed to identify the pathogen of oil palm (Elaeis guineensis) leaf spot disease in Hainan Province, China and examine the effects of environmental factors and fungicide sensitivity on the pathogen. The research confirmed that the pathogen responsible for this novel leaf spot disease was Colletotrichum siamense, marking the first report of this pathogen on oil palm in China. Field observations revealed summer-onset disease symptoms with concomitant leaf damage. The pathogen demonstrated optimal growth at a temperature of 30 °C and pH of 7.0, indicating its adaptability to prevailing climatic conditions in the region. Laboratory tests assessed the effects of various environmental factors on mycelial growth, revealing a marked decline in growth at temperatures below 20 °C and above 35 °C, as well as at acidic pH levels. Fungicide sensitivity assays identified pyraclostrobin, tebuconazole, prochloraz, and carbendazim as the most effective compounds, significantly inhibiting the growth of C. siamense with low EC₅₀ values. These findings provide essential information for developing effective disease management strategies to combat leaf spot disease in oil palm plantations. Full article

Anthracnose significantly threatens the cultivation of Polygonatum cyrtonema, severely impacting its quality and yield. Between 2022 and 2023, 50 Colletotrichum isolates were obtained from diseased leaves collected in three P. cyrtonema production areas within the Two Lakes region of China (Hubei and Hunan provinces). Morphological and molecular analyses identified six Colletotrichum species as the causative agents of anthracnose: C. aenigma, C. siamense, C. gloeosporioides, C. spaethianum, C. fructicola, and C. karsti. Among these pathogens, C. fructicola and C. spaethianum were predominant (82%), while C. siamense and C. fructicola exhibited the highest aggressiveness. Physiological investigations revealed that the optimal temperature range for all six pathogens was 25–28 °C. C. spaethianum thrived under acidic conditions, whereas C. aenigma, C. siamense, and C. gloeosporioides preferred alkaline environments. In contrast, C. fructicola and C. karsti showed no significant response to pH variations. Fungicide screening demonstrated that pyraclostrobin, prochloraz, and carbendazim effectively inhibited the growth of Colletotrichum species. These findings elucidate the epidemiological factors, primary pathogens, and effective control agents for P. cyrtonema anthracnose in the Two Lakes region, providing a basis for developing targeted prevention and control strategies. Full article

Coffee is a significant traded commodity for developing countries. Among the various diseases affecting coffee, anthracnose caused by Colletotrichum spp. has re-emerged as a major constraint on global coffee production. To better understand the Colletotrichum species complex associated with coffee anthracnose, we characterized Colletotrichum spp. using a combination of phenotypic traits, MAT1-2 (ApMat) gene analysis, multi-locus phylogenetic (ITS, ACT, CHS-1, and GAPDH), and pathogenicity assays. A total of 74 Colletotrichum isolates were collected from coffee plants exhibiting anthracnose symptoms across nine coffee plantations in China. Among these, 55 isolates were identified as the C. gloeosporioides species complex using the ApMat locus, while the remaining 19 isolates were identified through multi-locus phylogenetic analyses. The isolates represented seven Colletotrichum species from five species complexes: C. gloeosporioides (including C. siamense, C. nupharicola, and C. theobromicola), C. boninens (C. karstii), C. gigasporum (C. gigasporum), C. orchidearum (C. cliviicola), and C. magnum (C. brevisporum). This is the first report of C. nupharicola and C. cliviicola causing coffee anthracnose worldwide, and the first report of C. nupharicola in China. Pathogenicity tests confirmed that all seven species were capable of infecting coffee leaves. This research enhances our understanding of the Colletotrichum species responsible for coffee anthracnose, and provides valuable insights for developing effective disease management strategies. Full article

Currently, approximately one third of food is wasted; to counteract this, several novel packaging technologies have been developed to extend its shelf life, among which active packaging stands out. In this research, filmogenic solutions of pectin and beeswax with the addition of bioactive compounds as anthocyanins were developed and characterized to evaluate their potential application as active coatings. The antioxidant and antifungal activity of anthocyanins and coatings were determined, and the rheological properties, pH, color, SEM and FT-IR of the coatings were evaluated. The antioxidant activity of the anthocyanins had IC50 values of 79.52 and 56.14 μg/mL for DPPH^• and ABTS^•+, respectively, and 0.25% (w/v) for the antifungal activity against Colletotrichum siamense, which was inhibited by 32.16% and had morphological affectations in the fungus. The best formulation for coating was obtained with 3% (w/v) pectin, 1% (w/v) wax, and 1% (w/v) Tween 80, and 0.1, 0.25, and 0.5% anthocyanins were added. The rheological properties showed adequate viscosity values (0.08–0.12 Pa·s), and the pH values were acidic (3.05–3.78) and showed reddish tones. FT-IR analysis showed that the interactions between the components included the C=O stretching band being shifted due to intermolecular interactions and SEM micrographs showed that the film coatings presented continuous areas of pectin with embedded wax crystals. Promising results were obtained for antioxidant and antifungal activity for the coatings. The formulations presented suitable characteristics for their use as active coating in food. Full article