Symptom development on two wild, perennial grasses infected by Peronosclerospora species (Family Peronosporaceae: the downy-mildew fungi)

Abstract

The reproductive structures of the downy-mildew fungi, Peronosclerospora nobleiand Peronosclerospora eriochloae, develop only on chlorotic leaves of tall, vegetative tillers of the perennial grasses Sorghum leiocladum (wild sorghum) and Eriochloa pseudoacrotricha (early spring grass), respectively. They are never found on the leaves of flowering tillers, even when tillers of both types grow from the same tussock. The development of symptoms on infected tillers of both hosts and the morphological and anatomical changes to host tissues on infected tillers are detailed.