sentences:  Over time mycelia darken to form black, branching strands firmly attached to host roots; occasionally black dots are visible before this color change, indicating production of asexual and sexual survival structures.Darkened, mature hyphae can also develop and function as microsclerotia, however germination of microsclerotia has never been achieved in a laboratory setting nor observed in nature.Teleomorphic stages of "Rosellinia" spp.