Isolation and molecular characterization of three new fungal endophyte species from members of lauraceae in northern Thailand

Abstract

Endophytic fungi are common in plants and are defined as fungi that inhabit the living tissues of their hosts for part or all of their life cycle without causing disease symptoms in the plant. These fungi can adopt diverse lifestyles, functioning as mutualistic symbionts, commensal organisms, transient colonizers, or dormant saprophytes. It is important to investigate the endophytic communities in laurel plants, as they hold the potential to serve as biological control agents to inhibit plant pathogens, enhancers of the plant's defence mechanisms against pathogens and environmental stressors, or as potential substitutes for active plant compounds in medicinal development. Endophytic isolates obtained from plants of the Lauraceae family were investigated, resulting in the identification of three novel species. These isolates were collected from healthy leaves of Cinnamomum loureiroi, Litsea glutinosa, and Persea americana, and were characterized based on their morphology and multilocus gene sequencing. L. glutinosa, C. loureiroi, and P. americana were the sources of three newly discovered endophytic species: Colletotrichum litseae, Diaporthe lauraceicola, and D. perseicola. Among them, D. perseicola was assigned to the D. sojae species complex, while D. lauraceicola was placed within the D. arecae species complex. Particularly within the fungal genera Diaporthe and Colletotrichum, where species delineation remains complex and often challenging, the addition of new species can improve the resolution of closely related species, thereby reducing taxonomic confusion.