Document Type : Research Paper
Authors
1
Ph.D. Candidate, Department of Plant Protection, College of Agriculture and Natural Resources,University of Tehran, Karaj, Iran
2
Instructor of Rice Research Institute, Mazandaran Branch, Agricultural Research, Education and Extension Organization (AREEO), Amol, Iran
3
Professor, Department of Plant Protection, College of Agriculture and Natural Resources,University of Tehran, Karaj, Iran
4
Assistant Professor, Department of Biological Control Research, Iranian Research Institute of Plant Protection, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
5
Professor, Department of Botany, Iranian Research Institute of Plant Protection, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
Abstract
During survey of rice fields in Fars and Khuzestan provinces at mature grain stage, 42 seed samples were collected. Fusarium isolates were obtained from these samples by planting seeds on selective Fusarium medium (Pepton-PCNB-Agar, PPA) by two methods i.e.; surface sterilization by sodium hypochlorite (NaClO 1%) and without disinfection. Cultivated samples were kept in incubator at 25±1° C and intermittent light (12 hours of light and 12 hours of darkness). Morphological identification of 26 purified Fusarium isolates was performed on the WA, PDA, CLA and SNA. Phylogenetic relationships of 18 isolates on the basis of TEF1-α gene region and ITS1-5.8S-ITS2 region sequences were investigated. The results revealed that Fusarium isolates belonged to two species complexes FIESC (Fusarium incarnatum-equiseti species complex, 50%) and GFSC (Gibberella fujikuroi species complex, 46%). Fusarium fujikuroi species in Fars and F. semitectum species in Khuzestan were most frequent. Two species F. fujikuroi and F. andiyazi belonging to the GFSC species complex were identified in two separate clades in phylogentic tree based on TEF1-α. On the basis of TEF1-α gene, F. merismoides was not identified, but the ITS region sequence was identified as Fusicolla acetilerea and differentiated this species from Fusarium species in the phylogenetic tree.
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