phenotypic plasticity of the isolates assigned to pythium plurisporium

Pythium plurisporium was originally isolated from the roots of bentgrass (agrostis palustris). it is characterized by the production of multiple oospores in oogonium, which mostly has pedicellated stalk and swollen elements below its stalk. there are not many reports of the occurrence of this species in the literature. recently, a report of recovering p. plurisporium isolates from iran has been presented. nevertheless, the re-examination of the isolates referring to p. plurisporium using morphological identification as well as multiple gene genealogies, using both nuclear (its and btub) and mitochondrial (cox2) loci, arises the question about the existence of intraspecific phenotypic variation within this species. a revision of morphological characteristics among isolates assigned to p. plurisporium is discussed in the present paper.