Helotiales

Helotiales is an order of fungi within the class Leotiomycetes of the phylum Ascomycota. It is a large and diverse lineage, containing hundreds of species placed in various lifestyles, including saprotrophs, endophytes, and plant pathogens. Members typically form apothecia, ascomata that are cup- or disk-shaped, in which the asci develop. The group shows considerable morphological variation, and many species have small or inconspicuous fruiting bodies.

Ecology and distribution: Helotiales species occur in soils, leaf litter, decaying wood, and on living plant tissues in ecosystems worldwide. A substantial number are plant-associated, including endophytes and pathogens; Botrytis cinerea, the causal agent of gray mold, is one economically important member. Others contribute to the decomposition of plant material, participating in nutrient cycling.

Taxonomy and phylogeny: The order is defined largely by molecular phylogenetic relationships, and its composition has been refined with DNA data. It encompasses multiple families and a broad array of genera and species that exhibit diverse ecological roles.

Importance and notes: Some Helotiales species have significant agricultural or horticultural impacts as pathogens; many others are important decomposers or form symbiotic associations with plants. Ongoing molecular studies continue to clarify relationships within the order and with related lineages in Leotiomycetes.