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Broad bean (Vicia faba L.) is a cold-season legume crop, planted worldwide for its superior nutritional value and important role in sustainable agriculture. Leaf spot is one of the major diseases on broad bean leaves, stems and pods, the infections will result in severe yield reduction. In 2021, a leaf spot disease was extensively observed on broad bean plants in Longli County and Guiyang, Zunyi and Liupanshui Cities, Guizhou Province, China. Based on morphology and phylogenetic analysis using the ribosomal internal transcribed spacer region (ITS), 28S rRNA gene (LSU), β-tubulin (TUB2) and translation elongation factor 1-alpha (TEF1-α) gene sequences, the 12 isolates in this study represent two species of Nigrospora , namely N. musae , and N. oryzae. Moreover, the isolates of the two Nigrospora species found in the survey were tested for pathogenicity and indicated that they were all pathogenic to the broad bean plants. Same pathogens were successfully reisolated from the typical leaf spot lesions. Koch's postulates for N. musae and N. oryzae were fulfilled in this study. Thus, this study confirms species of Nigrospora as causal agents of leaf spot disease on broad bean in China, which provides a basis for subsequent research to develop effective preventative measures. • Identification of new pathogenic factors of broad bean leaf spot disease in Guizhou province. • First report of N. musae and N. oryzae as the causal pathogen of leaf spot on broad bean in China. • This study provides a basis for the follow-up studies on prevention measures of broad bean leaf spot diseases of broad bean. [ABSTRACT FROM AUTHOR]

Chinese chive (Allium tuberosum) is a perennial plant in Liliaceae family with highly edible and medicinal value, cultivated in many areas of the globe. From 2022 to 2023, a white spot disease showing nearly circular white spots, with brown mold layers growing on the surface, was observed in Puding, Guiyang, China, with an estimated incidence of 20–35%. To determine this disease, morphological characters, 5.8S nrDNA (ITS), 18S nrDNA (SSU), 28S nrDNA (LSU), partial translation elongation factor 1-alpha (TEF), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), RNA polymerase II second largest subunit (RPB2) and major allergen Alt-α1 (Alt - α1) multigene phylogenetic analyses and pathogenicity test were carried out, the results showed that the pathogen was A. arborescens. To our knowledge, this study firstly reported that A. arborescens was the causal agent of white spot disease on Chinese chive in China. • A white spot disease was first observed on Chinese chive (Allium tuberosum) in 2022. • The causal agent was identified as Alternaria arborescens. • This is the first report of A. arborescens causing white spot disease on Chinese chive. [ABSTRACT FROM AUTHOR]

Common bean is extensively grown and consumed worldwide and it is considered a nutraceutical food and an important source of protein. Leaf spot is one of the most devastating diseases of common bean in tropical and subtropical production areas. In May 2021, this destructive disease was observed in the Guizhou Province of China and resulted in serious economic losses for local agricultural production. Foliar symptoms appeared as small circular tan-colored spots, which then turned dark brown and coalesced into irregular water-soaked necrotic lesions, often leading to leaf wilt or abscission. Fungal isolates were obtained from symptomatic common bean plants and a detailed morphological analysis was performed. Concatenated phylogenetic reconstruction was conducted by amplifying and sequencing the internal transcribed spacer (ITS) region, glyceraldehyde-3-phosphate dehydrogenase (gapdh) and translation elongation factor 1-alpha (tef1-α) genes. Based on morphological characters and phylogenetic analyses, the pathogen was identified as Curvularia verruculosa. In addition, the pathogenicity tests of the isolates reproduced the same symptoms as those observed in the field, and Koch's postulates were confirmed by pathogen re-isolation and identification. To our knowledge, this is the first report of C. verruculosa causing leaf spot on common bean in the world. The current study can provide a foundation for developing effective management strategies, and reducing economic losses in common bean production. • The occurrence of leaf spot of common bean was observed in Guizhou Province, China. • Pathogen diagnosis was based on morphology and multi-locus phylogenetic analyses. • Koch's postulates proved the association of C. verruculosa with common bean leaf spot. • First report of C. verruculosa as the causal pathogen of leaf spot on common bean. • This study contributes to establish the control strategies for common bean diseases. [ABSTRACT FROM AUTHOR]