Host Range Variability and Geographic Distribution of Meliola Species (Meliolales)

Meliola is the largest genus in Meliolales that includes obligate, biotrophic foliar fungi growing on the surface of various plants parts, including leaves, stems, branches, and occasionally petioles of vascular plants. Meliola species occurs predominantly in tropical and subtropical regions. They are characterized by hyphal colonies on host surfaces and setae attached to these superficial hyphae, as well as distinctive morphological features of species of Meliolales, including unitunicate asci containing 2–4 pigmented, 3–4 septate ascospores. This study aims to analyze the host range and geographical distribution of Meliola species. Species delineation in Meliola is usually based host plant species names. However, how far naming of fungal species after host nomenclature is still questionable, as many morphologically similar Meliola species have been recorded from unrelated host plants. The range of host plants colonized by these species is highly variable with some species specialized to particular plant species. We conducted a comprehensive survey of Meliola species using published articles, books, and web-based resources. The highest species diversity was observed in tropical and sub-tropical environments. Current study focuses on the variability and geographical distribution of the genus Meliola. Meliola species have been recorded from different countries with different host plants. The enlisted data contains 177 plant families and 1765 Meliola species. These results provide a foundation for further ecological studies of species of Meliola and contribute to our understanding of fungal biodiversity and biogeography.