Wheat Fusarium head blight and identification of dominant species in Moghan area, Iran.

In order to identify of head blight agents in Moghan area and determine predominant species, totally 60 samples from affected wheat heads of Atila 4, Zagros, Goadloop, Izen green and Gasquine cultivars that cultivated during 2004-2005, were collected from randomly selected commercial wheat fields in Moghan. Twenty randomly selected kernels and glumes from each sample were surface sterilized and were planted on synthesized nutrient agar medium (SNA), potato dextrose agar (PDA) and Nash-Snyder medium (NA) plates. Culture plates were incubated at 22 to 25 C with a 12-h photoperiod provided by fluorescent and ultra violet lights. For the species identification, cultures were incubated for 5 to 15 days on PDA plates to induce sporulation under light and temperature previously described. Single conidial isolates were obtained by spreading a conidial suspension across a water agar culture plate and transferring a single germinated conidium to a new PDA culture plates. Single spore cultures were grown on Carnation leaf agar (CLA) for spore morphology assessment and on PDA for color assessment. All species were identified based on descriptions given in Burgess et. al. and Nelson et al. The results indicated that in addition Fusarium graminearum and F. culmorum were identified as wheat FHB agents in Moghan area and F. graminearum was dominant species in Moghan area. Also severe infection was determined in Atila 4 cultivar by F. graminearum.