Rainfall, particularly in continental climates with a monsoonal tendency, impacts the microbial niches during the growth of mountain cultivated ginseng. With shifts in the microbial community, diseases in ginseng cultivated and protected under rain shelter conditions may ultimately be altered. Such cultivation may influence microflora dynamics through variations in meteorological parameters; however, this is not yet clear. The present study found that rain shelter cultivation affected the distribution of fungal communities within mountain cultivated ginseng. This led to an improved community structure in the ginseng rhizosphere, characterized by the proliferation of antagonistic fungi and a reduction in pathogenic fungi. A correlation analysis of meteorological factors found that soil temperature and humidity were the primary meteorological factors affecting mountain cultivated ginseng. It is evident that rain shelter cultivation regulated the microecological environment of the mountain cultivated ginseng’s rhizosphere and resulted in positive outcomes. A disease investigation supported this finding. The incidence of ginseng root diseases, such as rust and root rot, was reduced by 5–6%. The incidence of ginseng leaf diseases, including gray mold and black spot, was reduced by 5–10%. This research provides evidence to address the dynamics of microbial ecology under rain shelter cultivation and its benefits for sustainable mountain cultivated ginseng management.

The filamentous fungus Elsinoë arachidis is a major foliar pathogen responsible for peanut scab, which is a significant disease affecting commercial peanut cultivation. Elsinochrome (ESC), produced by numerous phytopathogenic Elsinoë species, is a non-host-selective polyketide phytotoxin with strong photosensitive activity and plays a crucial role in pathogenesis on host plants. In E. arachidis, a dual-domain enzyme encoded by the gene ESCB3, containing both O-methyltransferase and a FAD-dependent monooxygenase domain, has been identified. To elucidate the role of ESCB3, the biological function, expression pattern of the ESC biosynthesis gene cluster, and associated metabolomics analyses were investigated in the present study. An ESCB3 deletion mutant (Δ ESCB3) was created by targeted gene disruption. Notably, ESC production was completely blocked in the Δ ESCB3 mutant, and the expression of ESC biosynthetic genes, except for the polyketide synthase gene ESCB1, was significantly downregulated. Additionally, the Δ ESCB3 exhibited heightened sensitivity to multiple stress tolerance compared with the wild type, especially oxidative stress/H ₂ O ₂ , highlighting the crucial role of ESCB3 in growth, development, and ESC biosynthesis in E. arachidis. Pathogenicity assays revealed a significant reduction in the pathogenicity of the Δ ESCB3 mutant, suggesting a possible correlation with the suppressed biosynthesis of ESC. Metabolomic analyses further confirmed that ESCB3 is indispensable for the ESC biosynthetic process and acts as a key regulatory factor. Collectively, the results of this study provide significant insights into the molecular mechanisms governing ESCB3-mediated virulence and ESC production in E. arachidis, offering potential targets for disease control strategies in peanut scab. [ ] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Mycocentrospora acerina is responsible for inducing severe leaf blight on Asarum heterotropoides. However, its poor sporulation under standard culture conditions significantly limits research on pathogenicity and disease management. This study aimed to develop an efficient high-yield and reproducible sporulation protocol by optimizing cultural conditions and nutritional factors. The results indicate that near-ultraviolet (Near-UV) light serves as a critical inducer of sporulation for M. acerina. In contrast to the standard culture on PDA medium at 20℃, where the pathogen fails to produce conidia, exposure to Near-UV light effectively stimulated sporulation, yielding a relatively robust production of 1.37×10³ conidia/mL after 21 days. Furthermore, V8 medium provided the optimal substrate conditions, yielding 4.56×10³ conidia/mL under the same cultural conditions after 14 days, a value significantly higher than those on other tested media. The optimized protocol (Near-UV light, V8 medium, 20℃, pH 7.0, 1 g/L glucose, and 1 g/L potassium nitrate) achieved a conidial yield of 1.0×10⁵ conidia/mL after 14 days. The conidia produced using the optimized sporulation protocol were morphologically identical to wild-type conidia and exhibited similar germination and pathogenicity. This established sporulation protocol provides vital materials for further studies, including infection, pathogenicity mechanism, and host-pathogen interaction dynamics and lays a theoretical basis for developing targeted strategies to control A. heterotropoides leaf blight.