Sclerotos

Sclerotos are a specialized fungal structure. They are hardened, resting masses of mycelium that are formed by many types of fungi. These structures are typically dark in color and can vary greatly in size and shape, often resembling seeds or small pebbles. Sclerotos serve as a survival mechanism for the fungus, allowing it to endure unfavorable environmental conditions such as drought, extreme temperatures, or nutrient scarcity.

When conditions become more favorable, such as increased moisture and appropriate temperatures, the sclerotium can germinate. This germination can lead to the formation of new vegetative hyphae, which will grow and spread to colonize a substrate, or it may produce fruiting bodies, the reproductive structures of the fungus. The durable nature of sclerotos allows them to persist in the soil or on plant debris for extended periods, acting as a reservoir of the fungus.

The formation and structure of sclerotos are important in fungal ecology and plant pathology. In agriculture, sclerotia of certain plant pathogenic fungi can be a significant source of inoculum, leading to recurrent disease outbreaks. Their hardened outer layer provides resistance to desiccation and some forms of chemical control, making their management challenging. Examples of fungi that produce sclerotos include species of Aspergillus, Penicillium, and Sclerotinia.