Lysobacter antibioticus HS124 inhibited mycelial growth of Fusarium graminearum (74.66%) under the dual culture method. Microscopic investigation clearly showed that amendment with different concentrations (10%, 30%, and 50%) of HS124 bacterial culture filtrate on potato dextrose agar plates caused abnormal hyphal structures, including swelling and distortion. Its inhibition toward mycelial growth of F. graminearum was increased with increasing concentration of n-butanol crude extract of HS124. The highest inhibition (43.14%) was detected at a crude concentration of 10 mg/disc, whereas the lowest inhibition (21.57%) was observed at 2 mg/disc. Although mycelial growth of F. graminearum was promoted by volatile organic compounds (VOCs) produced by HS124 as compared with the control, these VOCs clearly decreased fungal pigmentation resulting in a reduction of fungal sporulation. Microscopic investigation revealed hyphal deformation of F. graminearum due to VOCs. These compounds also had a negative effect on spore germination of F. graminearum. In vivo evaluations demonstrated that HS124 inoculation of wheat plants reduced crown rot disease incidence by 73.70% as compared with the control. HS124 inoculation of wheat plants also promoted most of the growth characteristics compared with the control or fungicide-treated plants. Our results provide strong evidence that HS124 could control F. graminearum infections and promote growth of wheat plants as part of management strategies for crown rot disease.

Grasses are cosmopolitan yet an important component in ecology. The current human population readily relies on grasses as many Poaceae species provide staple carbohydrate sources and staple feed to livestock. Ecologically grass plays a vital role as a pioneer inhabitant as well as sustaining immense biodiversity within the community. Fungi play a pivotal role in maintaining and shaping the grass communities. Fungi occur on grasses as commensals, saprobes, and pathogens. Each fungal community associated with grasses is responsible for the specific ecological property of the grass community, either in silviculture or polyculture. Hence, grass fungi drawn much attention from researchers. The taxonomy of grass fungi dates back to 1800s. However, up-to-date collective worldwide account for grass fungi is still lacking. In thi study, we compiled all the taxonomically valid data of Ascomycetous grass fungi in a checklist. The section Ascomycota comprises 3,165 fungal species among 207 families, 70 orders, and 11 classes. The majority of the species are represented by Dothideomycetes (1,367) and Sordariomycetes (944). This study is the first worldwide checklist of Ascomycetous grass fungi.

Phyllactinia cassiae-fistulae and its Ovulariopsis anamorph, a causal agent of powdery mildew on Cassia fistula, have been found in Thailand for the first time. Phylogenetic analysis using the 28S ribosomal DNA sequences clearly demonstrated that P. cassiae-fistulae distinctly formed a unique clade at the basal part of Phyllactinia with 100% bootstrap support. This phylogenetic analysis supports the unique morphology of P. cassiae-fistulae anamorph having cylindrical-ellipsoil conidia and short conidiophores similar to Oidium species.

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Tar spot is a common fungal disease often caused by Phyllachoraceae species, mostly on leaves and also on stems and fruits of a variety of host plant families. We identified a Neophyllachora species from Ficus religiosa leaves in Chiang Mai, Thailand. Phylogenetic analyses using maximum-likelihood (ML) and Bayesian inference (BI) showed the taxonomic placement of our taxon within Neophyllachora. The newly obtained sequences recovered as a sister and distinct clade to Neophyllachora fici with high bootstrap support. Our collection mainly differs from N. fici in having septate paraphyses, hyaline to olivaceous ascospores with 1-2 guttules, and mucilaginous sheath. A holomorphic fungus, Neophyllachora religiosa sp. nov. is introduced here based on the evidence from morpho-molecular analyses. The genus and the species are also identified as the first geographical record to Thailand and the first host record to Ficus religiosa. The synopsis table for the existing species of Neophyllachora and the key to the genus is provided.