This study provides a collection of biocontrol bacterial resources and genomic information for managing cowpea Fusarium wilt.
Abstract
Cowpea (Vigna unguiculata subsp. sesquipedalis, also known as yardlong bean) is an important winter horticultural crop in Hainan, and Fusarium wilt seriously threatens its yield and quality. To clarify the pathogen and screen antagonistic bacteria, surveys were conducted in 14 fields across Hainan’s major cowpea-growing areas. The causal agent was isolated, tested for pathogenicity, and identified using morphological and multigene molecular methods. Meanwhile, rhizosphere and endophytic bacteria from healthy plants were screened by dual culture, and candidate strains were phylogenetically analyzed using whole-genome sequencing (285 orthologous single-copy genes). Fusarium wilt occurred in all 14 fields (mean incidence 15.35%, range 3.20–76.40%). Of 44 fungal isolates, six were highly pathogenic and identified as Fusarium oxysporum. Twenty-two bacterial strains showed stable antagonism against F. oxysporum, with inhibition rates ranging from 42.62% to 68.47%. Phylogenetic analysis based on whole-genome sequences identified 15 Bacillus strains to the species level (12 B. velezensis, 2 B. subtilis, 1 B. tropicus), while the remaining seven strains belonged to Lysinibacillus (1), Pantoea (1), Klebsiella (1), Serratia (2), and Pseudomonas (2). Draft genome sequences of all 22 strains were obtained. This study provides a collection of biocontrol bacterial resources and genomic information for managing cowpea Fusarium wilt.
Fusarium wilt of Phalaenopsis spp., caused by Fusarium species, is a major soil-borne disease that severely threatens the yield and ornamental quality of Phalaenopsis. Endophytic fungi can serve as natural biocontrol agents against soil-borne pathogens and have potential applications in biological control. In this study, a pathogenic isolate, HT-1, was obtained from Fusarium-wilted Phalaenopsis plants, and its pathogenicity was confirmed through inoculation assays on detached leaves and intact plants. Morphological observations, together with internal transcribed spacer (ITS) and translation elongation factor 1-α (TEF-1α) sequence analyses, identified HT-1 as Fusarium proliferatum. Seven endophytic fungi with strong antagonism against F. proliferatum were screened using a dual-culture assay. All seven isolates consistently inhibited five representative plant pathogens in vitro, showing broad-spectrum and promising biocontrol potential. Detached leaf inoculation assays showed that both Trichoderma virens and Trichoderma asperellum significantly reduced lesion area and disease severity caused by F. proliferatum, indicating potential application in disease management. In summary, this study identified seven endophytic fungi from Phalaenopsis with broad-spectrum antagonistic potential against multiple plant pathogenic fungi. Meanwhile, the protective effects of T. virens and T. asperellum against F. proliferatum were preliminarily evaluated using detached leaves. These findings provide theoretical reference and fungal resources for screening candidate biocontrol strains against Phalaenopsis Fusarium wilt and related plant diseases, and lay a foundation for future studies on biocontrol mechanisms, whole-plant efficacy verification, and practical application.
Genome mining revealed eight biosynthetic gene clusters associated with antimicrobial secondary metabolites, supporting the genomic characterization of strain BS01 and identifying its biosynthetic potential and identifying its biosynthetic potential.
Van T. Tran, P. D. Tran, Don D. Le et al.· Journal of plant diseases an...· 0 citations
The dependence on synthetic fungicides in smallholder vegetable production creates both an economic and environmental concerns in sub-Saharan Africa. This study evaluated the biocontrol potential of two molecularly identified Trichoderma isolates, T. viride and T. harzianum, against Fusarium oxysporum and Cucumber mosaic virus (CMV) in tomato under controlled screenhouse conditions. The isolates were characterized using morphological traits and confirmed by ITS and tef1 sequencing. In vitro antagonism against F. oxysporum was assessed using serial spore concentrations, while in vivo efficacy was evaluated through pathogen challenge experiments measuring disease incidence, severity, plant growth, chlorophyll content, biomass, and root colonization over 12 weeks. Both isolates significantly suppressed pathogen activity, with T. viride showing stronger overall performance. In vitro, T. viride achieved 94.3% inhibition of F. oxysporum at 10⁹ CFU mL⁻¹ after 120 hours, compared with 91.7% for T. harzianum at same end point. Under screenhouse conditions, T. viride reduced Fusarium wilt incidence by 67% and CMV severity by 67%, whereas T. harzianum reduced Fusarium wilt incidence by 60% and CMV severity by 59% relative to pathogen-inoculated controls. Plants treated with T. viride also exhibited the greatest plant height, chlorophyll content, biomass accumulation, and root colonization, indicating enhanced plant vigour. In contrast, carbendazim effectively suppressed Fusarium wilt but provided no protection against CMV. These findings demonstrate that both Trichoderma species function as multifunctional bioagents capable of simultaneously suppressing fungal and viral diseases while promoting tomato growth, with T. viride showing superior overall efficacy and strong potential for sustainable integrated disease management.
E. E. Ekpiken· FUDMA Journal of Agriculture...· 0 citations
Abstract Fusarium wilt of tomato, caused by Fusarium oxysporum f. sp. lycopersici, is a major constraint to global production, causing up to 80% yield loss under favourable conditions. Plant growth-promoting rhizobacteria (PGPR) offer an eco-friendly alternative for disease management through growth promotion and pathogen suppression. This study aimed to isolate and characterise PGPR from tomato rhizosphere soils across different agro-climatic zones of Assam and evaluate their antagonistic potential under in vitro and glasshouse conditions. A total of 216 isolates were obtained, of which six showed strong antifungal activity (64–83% inhibition) in dual culture assays. Glasshouse evaluation revealed significant reduction in disease incidence (64.80–80.73%) over control. Molecular identification classified these isolates into Bacillus, Pseudomonas, Clostridium, Lysinibacillus, and Achromobacter. Biochemical analyses confirmed production of indole acetic acid, ammonia, siderophores, and phosphate-solubilizing compounds. These results demonstrate the potential of indigenous PGPR isolates as promising biocontrol agents for suppressing Fusarium wilt of tomato under greenhouse conditions. However, field validation and experiments including pathogen-free PGPR treatments are required to distinguish direct plant growth promotion from disease suppression before practical application.
L. Giri, Daisy Senapoty, P. Kaman et al.· Archives of Phytopathology a...· 0 citations
Fusarium oxysporum f. sp. cubense (Foc) is a soil-borne fungal pathogen responsible for fusarium wilt, which constitutes one of the major constraints in banana cultivation. Information on the occurrence and molecular characteristics of Foc in Malang Regency, one of the banana-producing areas in East Java, Indonesia, remains limited, hindering effective disease surveillance and management. This study was conducted to isolate and characterize fungal isolates associated with fusarium wilt disease in banana plants using an integrated approach combining morphological characterization, pathogenicity testing, PCR amplification, ITS sequence analysis, and phylogenetic analysis. Three fungal isolates were recovered from symptomatic banana plants collected in Donomulyo, Malang Regency, and one representative isolate (DNM) was selected for molecular characterization based on its morphological similarity to the other isolates. Morphological observations revealed characteristics typical of Fusarium oxysporum. ITS sequence analysis showed 100% query coverage and 100% sequence identity with reference Foc sequences available in GenBank, while phylogenetic analysis clustered the DNM isolate with reference Foc isolates with 94% bootstrap support. Pathogenicity assays demonstrated that the isolate induced typical fusarium wilt symptoms, resulting in an LDI of 16.39% at 14 DAI and an RDI of 41.67% at 45 DAI. These findings provide baseline information on putative Foc isolates in Malang Regency, particularly in the Donomulyo area, and establish an integrated characterization framework to support disease surveillance, early detection, and the development of integrated management strategies for fusarium wilt in banana production systems.
Akhmad Rizal Oktafian, Irisa Trianti, E. Yusnawan et al.· Agro Bali: Agricultural Jour...· 0 citations
Overall, this study demonstrates that multi-trait evaluation, integrating mechanistic screening and in planta validation, provides a more reliable framework for selecting effective biocontrol agents.
Safouane Benjaa, R. Bouharroud, S. Chafiki et al.· International Journal of Pla...· 0 citations
We use cookies to run the site and, with your consent, for analytics and to show ads.
See our Cookie Policy.