Deoxynivalenol and don - producing Fusarium graminearum isolates in wheat and barley crops in north and northwest areas of Iran

Deoxynivalenol (DON) contamination of 227 wheat samples from Golestan, Ardabil, Azarbaijan, and 154 barley samples from Golestan province all located in the north and northwest of Iran produced in 2006 were determined using ELISA method. DON was detected in 44.97 % of the wheat samples collected from Golestan province at levels from 18.53 to 192.81 ng g-1, with the average level of 40.99 ng g-1. Also 78.36 percent of Golestan's barley samples were contaminated to DON with the average level of 57.60 ng g-1 and at levels from 15.19 to 280.6 ng g-1. DON was not found in wheat samples of west Azarbaijan and only one sample from East Azarbaiejan was contaminated in this year, while it was detected in 92.30% of Ardabil's samples at levels from 32 to 316 ng g-1 with the average level of 130.23 ng g-1. DON contamination of wheat and barley produced at north and northwest of Iran in 2006 was much lower than the world regulatory limit for cereals. Thirty five wheat samples collected from Parsabad Moqan area to determine frequency of Fusarium graminearum incidence and natural DON contamination levels in 2011 using HPLC - IAC. Mean of the incidence of F. graminearum was 70. 91% in irrigated system cultivars and DON was detected in 90% of samples ranged from 1.06 to 2.06 µg g-1, at harvest time and 3.08 to 7.49 µg g-1 after storing. DON potential production of 29 F. graminearum isolates obtained from wheat of north and northwest ranged from 17.82 to 2397.33 ng g-1.