Damping-off disease in greenhouse cucumber in Iran

Abstract

This study was conducted during 2006–2007 in order to identify cucumber damping-off related to the greenhouses of Jiroft city (Iran). During this period, the samples were obtained from the greenhouses located in various sites of Jiroft. Plants with rot symptoms as well as soil samples were collected and transferred to the laboratory. Isolates existing in the soil were isolated by baiting method using sour orange leaf, cantaloupe seedling, apple fruit, hempseed and maize grain. In total, 151 isolates were obtained and clarified in two genera, Phytophthora sp. and Pythium sp., and five species including Phytophthora drechsleri, Phytophthora melonis, Pythium aphanidermatum, Pythium irregulare and Pythium ultimum. Among the investigated species, P. aphanidermatum with 50 isolates and Phytophthora melonis with 11 isolates had the most and the least abundance in the region, respectively. Pythium irregulare is considered as a first report from the cucumbers of Iran. Pathogenesis studies of the isolates were done in sterile soil under greenhouse conditions using corn grain as inoculum. Disease symptoms were subsequently determined.