Rhynchosporium secalis is an ascomycete fungus that is the causal agent of barley and rye scald.

Morphology

No sexual stage is known. The mycelium is hyaline to light gray and develops sparsely as a compact stroma under the cuticle of the host plant. Condia (2-4 x 12-20 μm) are borne sessilely on cells of the fertile stroma. They are hyaline, 1-septate, and cylindric to ovate, mostly with a short apical beak. Microconida have been reported, but their function is unknown. They are exuded from flasklike mycelial branches.

Host species

Sources