The causal organism Erysiphe graminis sp. tritici produces

The causal organism Erysiphe graminis sp. tritici produces Cleistothecia.
Erysiphe graminis f.sp. tritici is a plant pathogen that causes a fungal infection known as powdery mildew.
A cleistothecium (plural: cleistothecia) is a globose, completely closed fruit body with no special opening to the outside. The ascomatal wall is called peridium and typically consists of densely interwoven hyphae or pseudoparenchyma cells produced by fungus infection.