The diversity, occurrence and regional distribution of heterotrophic straminipiles and true zoosporic fungi (oomycetes and chytrids) recovered from freshwater bodies in two geographically and ecologically distant regions, the governorates of Assiut, Egypt and Jeddah, Saudi Arabia, were extensively investigated and compared in this study. For this purpose, one hundred surface water samples were collected from different localities of freshwater bodies in each governorate during the period from January 2009 to March 2013. In addition, the correlation between physicochemical characteristics (temperature, pH, total soluble salts and organic matter content) of the samples as abiotic factors affecting the diversity and occurrence of zoosporic mycobiota were considered during this research. The results indicate that Assiut Governorate is richer and more diverse in taxa of zoosporic fungi (22 identified and 3 unidentified species classified into 8 genera) than Jeddah Governorate (9 identified and 2 unidentified species belonging to 4 genera). The most dominant genera recovered from the samples were Saprolegnia and Achlya, but these genera showed various frequencies of occurrence. Generally, the majority of the prevalent isolated species of zoosporic fungi were different in the two regions, and identical genera and species showed clear differences in terms of occurrence and distribution. An inverse correlation was revealed between the temperature of the samples and the diversity of isolated zoosporic fungal species. An inconsistent trend was found between the pH of the samples and species diversity: while the correlation was positive in Assiut Governorate, it was negative in Jeddah Governorate. The total soluble salts and organic matter content of the samples in the two governorates correlated positively with the diversity of isolated species.
El-Nagdy M. A., Ali E. H., Rawaa A. M., El-Garni S. (2022): Comparative study of the diversity of zoosporic fungi (oomycetes and chytrids) in freshwater bodies in Assiut Governorate, Egypt and Jeddah Governorate, Saudi Arabia. – Czech Mycology 74(2): 153–179.
