IDENTIFICATION OF SOIL PYTHIUM SPECIES IN FARS PROVINCE OF IRAN

Document Type: Regular Paper

Authors

Department of Plant Protection, College of Agriculture, Shiraz University, Shiraz, I. R. of Iran

Abstract

During 2000-2001, soil Pythium species were studied in Fars province. Soil samples were
collected from various parts of the province (Abadeh, Bajgah, Bayza, Borazjan, Darab, Estahban, Fasa,
Khafr, Sepidan, Shiraz, Moharloo, and Zarghan). Isolates were recovered from soil by baiting. Species
were identified based on morphological characters of sexual and asexual organs, growth rate at different
temperatures, and colony morphology on various media. From 270 isolates of Pythium recovered, 12
species and two groups were identified as: P. aphanidermatum*, P. aquatile, P. deliense, P. diclinum, P.
echinulatum, P. inflatum, P. okanoganense, P. oliganderum, P. orthogonon, P. ostracodes, P. rostratum,
P. vexans, Pythium Group “G”*, and Pythium Group “HS”* (species with asterisk were predominant).
P. aquatile, P. diclinum, P. echinulatum, P. inflatum, P. okanoganense, P. oliganderum, P.
orthogonon, P. ostracodes, P. rostratum, and P. vexans are new for Fars, and P. aquatile, P.
echinulatum, P. inflatum, P. okanoganense, P. orthogonon, P. ostracodes, and P. rostratum are new for
Iran flora.
A key is also presented for identification of Fars Pythium species.

Keywords