Morphology and ITS-based phylogeny revealed Nigrospora sphaerica causing leaf spot and blight disease of Bambusa polymorpha in India

Bamboo spp. are a significant source of raw materials for the paper and pulp industries worldwide. Therefore, it is crucial to identify pathogens accurately since they can pose a significant threat to bamboo in nurseries and plantations. In January 2021, symptoms of leaf spot and blight disease were observed on Bambusa polymorpha in the central nursery of Forest Research Institute, Dehradun, India. After examining the morphological characteristics and conducting a phylogenetic analysis of the internal transcribed spacer (ITS) region of ribosomal DNA, Nigrospora sphaerica was identified as the causative agent. In pathogenicity experiments, N. sphaerica induced disease symptoms and was successfully re-isolated from the inoculated leaves, thereby satisfying Koch's postulates. This study marks the first report of N. sphaerica as a foliar pathogen of B. polymorpha in India. Further research should focus on developing strategies to manage this disease in bamboo nurseries. [Display omitted] •This study reports Nigrospora sphaerica as a foliar pathogen of Bambusa polymorpha for the first time in India.•The pathogen was identified based on microscopic features, ITS sequence analysis and pathogenicity tests.•This is a new taxonomic addition to the diversity of pathogenic bambusicolous fungi.•This study provides directions to study the host range and develop control methods for N. sphaerica and other bamboo pathogens.