The Current Status of Phytopythium Species in Iran: Challenges in Identification of an Intermediate Taxon

Document Type : Review Article

Authors

Department of Plant Protection, School of Agriculture, Shiraz University, Shiraz, Iran Shiraz University

10.22043/MI.2022.360305.1237

Abstract

 
Phytopythium is a cosmopolitan genus found in different regions of the world from various substrates. This genus is a newly described taxon that was once a member of the genus Pythium sensu lato. Phytopythium is an intermediate genus between Pythium and Phytophthora with 34 formally described species. Recently, some studies focused on the phylogeny of this genus in Iran. Although not many studies concentrated on isolating species assigned to this genus from Iran, some comprehensive studies showed that Phytopythium is an important genus with vast distribution in this part of the world. Accurate identification and classification of Phytopythium species are quite challenging. Morphological identification of Phytopythium is troublesome due to the lack of identification keys, overlapping of some morphological features, the presence of species complexes, pleomorphism, and the absence of certain structures in some species. Besides, most species cannot be separated using only one or two loci for the phylogenetic analyses. In addition, some studies in Iran do not include molecular investigations to support their morphological identification or make it possible to reidentify the reported species. Having no accurate and current checklist of the country’s species also adds to the problem. This review focuses on the current systematics of Phytopythium species in Iran, discussing the challenges in the morphological and molecular identification of the species in the country. It also proposes some approaches to address the problem of characterizing the species in the genus Phytopythium.  

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