Multi-omics profiling reveals antagonistic strategies of endophytic Streptomyces sp. MEPP0209 against Lasiodiplodia theobromae causing Dendrobium officinale stem rot.

Comparative Insights into Bacterial Endophytome and Antifungal Metabolites in Fusarium Wilt-Resistant and -Susceptible Banana Cultivars Unveil the Resistance Toward Fusarium oxysporum f. sp. cubense

India contributes 26% of global banana production, yet cultivation is severely threatened by Fusarium wilt (Fusarium oxysporum f. sp. cubense, Foc), necessitating sustainable, eco-friendly management strategies. This study evaluated the biocontrol potential of endophytic bacteria isolated from Foc-resistant and -susceptible banana cultivars. Isolates from the pseudostem, corm, and root of the resistant cultivar showed significantly greater inhibitory activity than those from the susceptible cultivar, underscoring the role of host genotype in shaping functionally competent endophytic communities. Among all isolates, Bacillus sp. from the corm of cv. Rose (AB) showed the highest mycelial inhibition of Foc (70.37–76.54%) in vitro. GC-MS-based metabolite profiling revealed a chemically diverse array of secondary metabolites, fatty acid esters, steroids, terpenoids, siloxanes, and nitrogenous compounds. Corm-associated endophytes exhibited membrane-disruptive and cytotoxic activity, while root-associated endophytes contributed protective, defense-modulatory effects. Halomonas sp. RoRo2 and B. subtilis RoC1 showed the highest inhibition in both agar-well and in planta assays, with unsaturated fatty acids and organic acid derivatives implicated as key antifungal effectors acting through multiple biochemical pathways. These findings identify metabolically versatile endophytes as promising candidates for developing efficient, environmentally compatible bioinoculants as sustainable alternatives to chemical control of Fusarium wilt in banana.

Integrative functional profiling of rhizospheric and endophytic bacteria reveals Lelliottia aquatilis as a multifunctional PGPR in Himalayan ecosystems

This study introduces L. aquatilis strain MC3 as an emerging candidate for bioinoculant development and one of the first reports for identification of L. aquatilis as multifunctional PGPR from Himalayan ecosystems.

Mechanisms of Biocontrol on Poplar Anthracnose and Growth Promotion by Trichoderma asperelloides Tas369 and Tri-Trichoderma Composite Strain

To address the need for effective biocontrol of poplar anthracnose caused by Colletotrichum gloeosporioides, in this study, 20 Trichoderma strains were isolated from the rhizosphere of seven tree species on Tianzhu Mountain to screen for potent growth-promoting and antifungal agents. The inhibitory effects of the strains on C. gloeosporioides (Cgl) were evaluated through mycelial growth assays, volatile organic compound tests, and fermentation filtrate analysis, while their growth-promoting capabilities and induction of systemic resistance were assessed in poplar seedlings via biomass measurement, stomatal analysis, and gene expression profiling. The results demonstrated that T. asperelloides Tas369 significantly inhibited pathogen growth and improved seedling growth, increasing stomatal density by 134% and inducing phenylalanine ammonia-lyase (PAL) and peroxidase (POD) enzyme activities. Notably, Trichoderma composite (Tcom) outperformed single-strain treatments, achieving 89.8% control efficacy, reducing the malondialdehyde content by 1.1 mmol/g, and significantly upregulating the key defense genes NPR1 (14.32-fold) and PR1-1 (219.79-fold) through increased activity of the salicylic and jasmonic acid signalling pathways. In conclusion, while Tas369 exhibits strong individual potential, the Tcom consortium provides superior biocontrol through multiple mechanistic interactions, offering an effective and sustainable approach for managing poplar anthracnose in forestry applications.

Genome based characterization of an endophytic Bacillus subtilis BS01 associated with suppression of Fusarium wilt in Cavendish banana caused by Fusarium oxysporum f. sp. cubense Tropical Race 4

Antifungal Activity and Transcriptomic Profiling of Equisetin from Endophytic Fusarium incarnatum Y2 Against Major Wheat Root and Crown Rot Pathogens

Background/Objectives: Wheat root and crown rot, caused by Fusarium pseudograminearum, Fusarium graminearum, and Bipolaris sorokiniana, are devastating soil-borne diseases that cause substantial yield losses worldwide. Endophytic fungi are promising sources of bioactive metabolites for agricultural applications. This study aimed to isolate and characterize an endophytic fungus with antifungal activity against major wheat pathogens, identify its active compound, and investigate the underlying transcriptional response. Methods: An endophytic strain Y2 was isolated from Hedyotis diffusa leaves and identified through morphological and phylogenetic analysis based on TEF-1α and RPB2 sequences. Pathogenicity of strain Y2 was evaluated on wheat stem bases. The bioactive compound was purified by HPLC and identified by HR-ESI-MS and NMR. Antifungal activity was assessed using dual-culture and microbroth dilution assays. Transcriptomic analysis (RNA-seq) was performed on F. pseudograminearum treated with equisetin, with qRT-PCR validation of seven representative differentially expressed genes. Results: Strain Y2 was identified as Fusarium incarnatum or a closely related member of the F. incarnatum–equiseti species complex (FIESC) and confirmed to be non-pathogenic to wheat. The purified bioactive compound was characterized as equisetin, which exhibited significant antifungal activity with MIC values of 16, 32, and 64 μg/mL against F. pseudograminearum, B. sorokiniana, and F. graminearum, respectively. Transcriptomic analysis revealed that equisetin treatment induced a polarized transcriptional response in F. pseudograminearum, characterized by strong upregulation of ribosome and translation-related genes and widespread downregulation of other metabolic pathways, particularly nitrogen metabolism. qRT-PCR validation of seven representative genes confirmed the reliability of the RNA-seq data. Conclusions: Our findings demonstrate that equisetin is the active antifungal metabolite produced by F. incarnatum Y2, with potent in vitro activity against major wheat root and crown rot pathogens. The transcriptomic data provide insights into the potential mechanism of action, while the non-pathogenic nature of strain Y2 supports its biosafety. Although these results highlight equisetin as a promising lead compound for antifungal development, further in planta efficacy and safety studies are required before it can be considered for practical biocontrol.

Streptomyces songxianensis sp. nov. SX92T: biocontrol of tobacco black shank and modulation of the rhizosphere microbiome

Strain SX92 T is proposed as the type strain of a novel species, Streptomyces songxianensis, and is established as a promising multifunctional biocontrol agent for sustainable tobacco production.