Dominance of ascomycota and ubiquity of Trichoderma in Argemone mexicana microbiomes across Assam, India

Abstract

In India, Argemone mexicana is known for its pharmaceutical value. The plant hosts many endophytes. Plant-associated microbes also help plants with development and protection. A metagenomic study of rhizospheric soil, roots, and shoots was conducted to investigate variation in the organization and diversity of fungal communities from two different locations (Amlighat and Dergaon, Assam, India) for the first time. Illumina sequencing was used for the fungal metagenomic analysis. The DNA library was constructed using primers specific for the fungal internal transcribed spacer 2 (ITS2) region. Next-generation sequencing identified a total of 5 phyla, 32 classes, 39 orders, 68 families, 125 genera, and 273 fungal species (including unknown and unidentified taxa) in triplicate samples. The fungal taxa were mostly similar in both locations but occurred at varying relative abundances. The fungal community richness was higher in the root samples from Dergaon than in the other samples. Ascomycota (37.47%–75.84%) was the dominant phylum across all samples, followed by Basidiomycota (3.53%–6.95%). Beta diversity analyses, including principal component analysis, cluster analysis, unweighted pair group method with arithmetic mean (UPGMA), and network analysis, also showed a close relationship between the fungi of both locations. We observed mostly similar fungal diversity, with some differences, among the roots and shoots of A. mexicana and its rhizospheric soil. Trichoderma species were detected in all samples at varying relative abundances. These findings suggest that this fungus may modulate acaricide production in A. mexicana .