Phytopathologia Mediterranea 58(1): 115-125, 2019 Firenze University Press www.fupress.com/pm Phytopathologia Mediterranea The international journal of the Mediterranean Phytopathological Union ISSN 0031-9465 (print) | ISSN 1593-2095 (online) | DOI: 10.14601/Phytopathol_Mediterr-23860 Citation: Dehghanpour-Farashah S., Taheri P., Falahati-Rastegar M. (2019) Virulence factors of Fusarium spp., causing wheat crown and root rot in Iran. Phytopathologia Mediterranea 58(1): 115-125. doi: 10.14601/Phyto- pathol_Mediterr-23860 Accepted: November 14, 2018 Published: May 15, 2019 Copyright: © 2019 Dehghanpour-Far- ashah S., Taheri P., Falahati-Rastegar M. This is an open access, peer- reviewed article published by Firenze University Press (http://www.fupress. com/pm) and distributed under the terms of the Creative Commons Attri- bution License, which permits unre- stricted use, distribution, and reproduc- tion in any medium, provided the origi- nal author and source are credited. Data Availability Statement: All rel- evant data are within the paper and its Supporting Information fles. Competing Interests: The Author(s) declare(s) no confict of interest. Editor: Dimitrios Tsitsigiannis, Agricul- tural University of Athens, Greece. Research Papers Virulence factors of Fusarium spp., causing wheat crown and root rot in Iran Saeedeh DEHGHANPOUR-FARASHAH, Parissa TAHERI * , Mahrokh FALAHATI-RASTEGAR Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, P.O.Box: 91775-1163, Mashhad, Iran *Corresponding author: p-taheri@um.ac.ir Abstract. Crown and root rot of wheat, caused by Fusarium spp., limit crop yields worldwide, from rotting of seeds, seedlings, crowns, roots and basal plant stems. Viru- lence factors and virulence and aggressiveness of Fusarium spp. were investigated for isolates from Iran, obtained from wheat plants with crown and root rot symptoms. Forty isolates of Fusarium were used in this research. Among the isolates, nivalenol (NIV) was detected as the dominant trichothecene chemotype produced. Production of trichothecenes and zearalenone (ZEA) in autoclaved rice cultures of Fusarium iso- lates was analyzed using high performance liquid chromatography. Te levels of NIV ranged from 258 to 1246 μg kg −1 , of deoxynivalenol (DON) from 45 to 1411 μg kg −1 , and of ZEA from 53 to 3220 μg kg −1 . All Fusarium isolates produced cellulase and pec- tinase enzymes. Positive correlation was observed between activity of cell wall degrad- ing enzymes (CWDEs) produced by the isolates and their pathogenicity on wheat leaf segments. Virulence of trichothecene-producing isolates was greater than that of non- trichothecene-producing isolates. Considerable association was detected between the capability of Fusarium spp. isolates to produce virulence factors (such as mycotoxins and CWDEs) and their pathogenicity on wheat. Keywords. Cell wall degrading enzymes, mycotoxins. INTRODUCTION Crown and root rot of wheat, caused by several Fsarium species, occur in most cereal producing regions of the world, including Europe, Australia, North America, South America, West Asia, South Africa and North Africa (Smiley et al., 1996; Paulitz et al., 2002; Smiley et al., 2005). In Iran, sev- eral Fusarium spp. have been isolated from crown and root rot symptoms in wheat growing regions (Besharati Fard et al., 2017). Fusaria produce a diverse array of toxic secondary metabolites (mycotoxins), which are involved in pathogenicity of these fungi to host plants. Te most important Fusarium mycotoxins are trichothecenes and zearalenone, which can con- taminate agricultural products, making them unsuitable for food or feed (Ma et al., 2013).