acervulus An asexual, conidia-bearing structure that is formed by certain fungi parasitic in plants. It consists of a mat of fungal tissue which bears a layer of conidiophores; initially formed within the plant tissues, it later breaks through to the surface to release conidia.

acervulus An asexual structure, bearing conidia (i.e. thin-walled, asexual spores), that is formed by certain fungi parasitic (see parasitism) in plants. It consists of a mat of fungal tissue which bears a layer of conidiophores (i.e. specialized hypha that bear conidia); initially formed within the plant tissues, it later breaks through to the surface to release conidia.