Biodiversity of entomopathogenic fungi in soils of eastern China

Sustainable agriculture requires the development of biological control technologies. Entomopathogenic fungi (EPF) are important resources of microbial control agents, yet their diversity in soil with various habitats remains poorly understood. In this study, we systematically investigated the EPF diversity in soils of eastern China. A total of 455 strains of 42 EPF species belonging to 18 genera were isolated and identified from 540 soil samples collected from 108 sites representing five habitats (crop, orchard, forest, fallow, and grasslands) in Anhui, Jiangsu, Jiangxi, Shandong, Shanghai, and Zhejiang regions. Habitats had a greater influence on EPF diversity than regions. Overall, EPF diversity in natural habitats (forests and grasslands) was slightly higher than in agricultural habitats (crops, orchards, and fallow lands), particularly in terms of species richness. Among agricultural habitats, orchard had the highest evenness and relatively low species richness, while fallow land showed the lowest diversity, which may be related to management intensity or vegetation cover. Furthermore, the results also demonstrated the similarity of the EPF community structures among different habitats or regions; <i>Purpureocillium lilacinum</i> was the dominant species, while <i>Penicillium citrinum</i> and <i>Metarhizium anisopliae</i> were the minor dominant species in all habitats. In contrast, <i>Metarhizium robertsii</i>, <i>Penicillium janthinellum</i>, <i>Marquandomyces marquandii</i>, and <i>Trichoderma spirale</i> exhibited variable dominance depending on the habitat. This research provides new insights to understand the fungal diversity.IMPORTANCEWe recognized a total of 455 strains of 42 entomopathogenic fungi (EPF) species in 18 genera, including 7 putative new species with substantial insecticidal activity, which have potential for application as biological control agents. The discovery will enhance the understanding that agricultural activity interferes with the EPF distribution. Furthermore, the results highlight the conservation and application of EPF.