The fungal genus Pyrenophora includes 191 species http://www.speciesfungorum.org/Names/names.asp?strGenus=Pyrenophora, including the following plant pathogenic species: P. teres

Pyrenophora teres

Pyrenophora teres is a necrotrophic fungal pathogen of some plant species, the most significant of which are economically important agricultural crops such as barley.- Dispersal and spread :...

, P. graminea

Pyrenophora graminea

Pyrenophora graminea is the causal agent of barley stripe. Barley stripe is disease of barley that once caused significant crop yield losses in many areas of the world.-Identification:...

and P. tritici-repentis

Pyrenophora tritici-repentis

Pyrenophora tritici-repentis is a plant pathogen of fungal origin, causing a disease called tan spot or helminthosporiosis, that affects mainly wheat in its more common varieties. It forms characteristic, dark, oval-shaped spots of necrotic tissue surrounded by a yellow ring...

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P. teres (teleomorph Drechslera teres) makes up to 3 conidia per conidiophore. It infects plants with an appressorium

Appressorium

An appressorium is a flattened, hyphal "pressing" organ, from which a minute infection peg grows and enters the host, using turgor pressure capable of punching through even Mylar....

. It grows biotrophically in the first infected plant cell, but then switches to a necrotrophic growth mode. During necrotrophic growth the fungus can only be found in the plant apoplast

Apoplast

Within a plant, the apoplast is the free diffusional space outside the plasma membrane. It is interrupted by the Casparian strip in roots, air spaces between plant cells and the cuticula of the plant....

but not within plant cells.