The aim of this study is to explore the relationship between soil nutrients and berry quality for the wine grape Vitis vinifera cv. Cabernet Franc in the eastern foothills of the Helan Mountains, and subsequently to optimize soil nutrient conditions for optimal berry quality, thus providing guidance for vineyard soil management. Based on the basic data on soil nutrients and berry quality indicators, a partial least squares regression method was used to screen for major soil nutrient factors affecting the grape quality index. Then, the selected soil nutrient factors were taken as independent variables and the corresponding grape quality indicators were taken as dependent variables and a multilinear regression equation was formulated by the method of multivariate linear regression. Finally, the optimal solution for fruit quality and soil nutrients was solved using linear programming equations. The results showed that there was a lack of total nitrogen, organic matter, nitrate nitrogen, ammonium nitrogen, and available phosphorus in the soil nutrients, and an alkaline soil. There is a significant positive correlation between some soil nutrient indices, and there is also a multivariate linearity problem. Among all berry quality indices, titratable acid, tannin, and anthocyanin were negatively correlated with eleven and ten soil indices, respectively, while other berry quality indices were positively correlated with most soil nutrient indices. The optimal parameters for grape quality were determined using the method of linear programming equations, and the corresponding soil nutrient indicators content were defined.

Leaf-blight disease caused by the Fusarium oxysporum is an emerging problem in Dendrobium chrysotoxum production in China. Symptoms of leaf blight were observed on seedlings of D. chrysotoxum cultivated in a nursery in Ruili City, Yunnan Province, China. In this study, we isolated the Fusarium sp. associated with leaf-blight disease of D. chrysotoxum from the diseased seedlings. A pathogenicity test was performed to fulfill Koch’s postulates to confirm the pathogenicity of isolated strains and identified using morphological and molecular techniques. The results revealed that all four isolated Fusarium sp. isolates (DHRL-01~04) produced typical blight symptoms followed by marginal necrosis of leaves on the D. chrysotoxum plants. On the PDA medium, the fungal colony appeared as a white to purplish color with cottony mycelium growth. Microconidia are oval-shaped, whereas macroconidia are sickle-shaped, tapering at both ends with 2–4 septations. The phylogenetic trees were construed based on internal transcribed spacer (ITS), translation elongation factor (EF-1α), and RNA polymerase subunit genes RPB1 and RPB2 genes, respectively, and blasted against the NCBI database for species confirmation. Based on the NCBI database’s blast results, the isolates showed that more than 99% identify with Fusarium oxysporum. To our knowledge, this is the first comprehensive report on the identification of Fusarium oxysporum as the causal agent of Dendrobium chrysotoxum leaf blight in Yunnan Province, China, based on morphological and molecular characteristics.

Verticillium-like fungi within the Sordariomycetes hold significant ecological and economic importance, especially in biocontrol. This study describes two novel species, Leptobacillium gasaense and Ovicillium yunnanense, and provides DNA sequence data and identification keys for the genera Leptobacillium and Ovicillium. The genus Muscodor, known for its considerable biotechnological value, comprises endophytes characterized by sterile mycelia that produce antibiotic volatile organic compounds (VOCs). Historically, the classification of Muscodor has relied on culture characteristics, VOC chemical profiles, and molecular phylogenetic analyses. However, culture characteristics and VOC profiles lack a definitive diagnostic value. Although asexual morphological traits are crucial for genus-level classification, no conidiogenous structures have been observed in Muscodor. Here, we report the asexual morphological characteristics of Muscodor and describe M. coffeanus as a new record in China, supported by both its asexual morphology and molecular phylogenetic evidence.

Termite-associated Ophiocordyceps species remain understudied despite the high diversity of the genus. Here we describe Ophiocordyceps minuta (holotype CXAC 0026) from termites (Termitidae, Macrotermitinae) collected in Yunnan, China. Phylogenetic analyses based on nrLSU (nuclear large subunit ribosomal RNA), tef1-α (translation elongation factor 1-alpha), and rpb2 (RNA polymerase II second largest subunit) sequences resolve this fungus as a distinct lineage. Notably, deep genetic divergence (65 bp in tef1-α) between the two ex-type strains of the allied O. fusiformis (BCC 93025 and BCC 93026) reveals cryptic diversity within that nominal species. Beyond the new species, a morphological assessment of termite-associated Ophiocordyceps indicates that perithecial immersion status, ascospore morphology, and conidial features are the most taxonomically valuable characters for this ecological group. These findings expand the known diversity in southwest China and underscore the importance of integrating phylogenetic data with key morphological traits for species delimitation in under-explored habitats.

Background: Xanthomonas oryzae pv. oryzae (Xoo) causes rice leaf blight (BLB) and poses a major threat to global rice production. In rice production, tetramycin agents provide good control of rice leaf blight, while the standardization of the reference genes of Xoo under tetramycin stress has not been reported. The aim of this study was to identify the most stable reference genes for quantitative PCR analysis of Xoo under tetramycin stress. Methods: Six candidate reference genes, gyrB (RNA polymerase β gene), GADPH (glyceraldehyde-3-phosphate dehydrogenase gene), recA (recombinase A gene), gyrA (citrate synthase encoding gene), dnaK (molecular chaperone protein gene), and 16S rRNA (16S ribosomal RNA gene) were selected and their expression stability was assessed under tetramycin stress conditions using real-time quantitative PCR (qRT-PCR). GeNorm, NormFinder, BestKeeper and RefFinder were used to assess the expression stability, the relative expression values of the eight genes involved QS (Quorum sensing) pathway under tetramycin stress were used to validate by the rpf (regulation of pathogenic factors) gene family. Results: 16S rRNA expression was most stable under tetracycline stress, whereas GADPH was the least. The rpf gene family showed a highly stable expression level, confirming the reliability of 16S r RNA as a reference gene in the study of Xoo under tetramycin stress. Conclusions: 16S rRNA was identified as the best reference gene for Xoo gene expression analysis under tetramycin stress. It provides a reliable support for the molecular research on the control strategy of rice BLB.

Background: Ligusticum L. plants exhibit significant morphological variation in leaves, flowers, bracteoles and mericarps, thus the classifications of members for the genus have always been controversial. Among them, the taxonomic problem of Ligusticum multivittatum Franch. is the most prominent, which has not been sufficiently resolved so far. Methods: to clarify the taxonomic position of Ligusticum multivittatum, we performed phylogenetic analyses based on plastome data and ITS sequences. Meanwhile, we conducted comprehensively comparative plastome analyses between Ligusticum multivittatum and fifteen Ligusticopsis species. Results: Both analyses robustly supported that Ligusticum multivittatum nested in genus Ligusticopsis Leute and formed a clade with fifteen Ligusticopsis species, belonged to the Selineae tribe, which was distant from the type species of Ligusticum (Ligusticum scoticum), located in the Acronema clade.The comparative results showed that sixteen plastomes were highly similar and conservative in genome structure, size, gene content and arrangement, codon bias, SSRs and SC/IR. These findings imply that Ligusticum multivittatum is a member of Ligusticopsis, which was further verified by their shared morphological characters: stem base clothed in fibrous remnant sheaths, white petals, pinnate bracteoles, dorsally compressed mericarps with slightly prominent dorsal ribs, winged lateral ribs and numerous vittae in the commissure and in each furrow. Therefore, combining with the evidences of phylogenetic analyses, plastome comparison and morphological features, we affirmed that Ligusticum multivittatum indeed belonged to Ligusticopsis and transformed it into Ligusticopsis conducted by Pimenov was reasonable. Conclusions: Our study not only confirms the classification of Ligusticum multivittatum by integrating evidences, but also provides a reference for resolving taxonomy of contentious taxa.