Wheat seed contamination with seed-borne diseases in cold climatic zone of Iran

In order to evaluate the informal wheat seed contamination with seed-borne diseases, two most important provinces (East Azarbaijan and Khorasan Razavi) for wheat production were selected in cold region of Iran in 2008-2009 crop seasons and ten different locations (city or village) were considered in each province and ten informal seed farmers were selected randomly. A seed sample (1 kg) was taken from planting source of each farmer. Different analysis including purity, germination and seed health (head blight, common bunt and loose smut disease) tests carried out on seed samples according to ISTA rules. Fusarium graminearum was identified as the main disease in provinces. Blotter test showed significant differences (P < 0.05) among the towns but there was no meaningful difference between provinces. Washing test for T. caries showed significant difference between the two provinces (P < 0.1) but there was no meaningful difference among towns in each province. Furthermore there was significant difference between and among provinces and towns with respect to T. leavis infection. Also the data showed clear dispersal of these two species (T. caries and T. leavis). Negative and high significant correlation was observed between U. tritici and germination. So the precision study of seed borne disease in different areas of the country for producing healthy seed is recommended. Keywords: Wheat seed; F. graminearum; T. leavis; U. tritici; T. caries.