Journal of Agricultural Science; Vol. 4, No. 8; 2012 ISSN 1916-9752 E-ISSN 1916-9760 Published by Canadian Center of Science and Education 199 Reaction of Wheat Genotypes to T. laevis Kühn and T. controversa Kühn, the Common and Dwarf Bunts Pathogens in the Dry Highlands of Iran Kaivan Karimi 1 , Jahanshir Amini 2 , Mahmoud Moradi 1 , Homayoun Kanouni 3 & Maghsoud Hassanpour Hosni 4 1 Department of Plant Protection, Agriculture and Natural Resources Research Center of Kurdistan, Sanandaj, Iran 2 Department of Plant Protection, University of Kurdistan, Sanandaj, Iran 3 Department of Seed and Plant Improvement, Agriculture and Natural Resources Research Center of Kurdistan, Sanandaj, Iran 4 Department of Cereal Research, Dryland Agricultural Research Institute (DARI), Maragheh, Iran Correspondence: Jahanshir Amini, Department of plant protection, University of Kurdistan, Sanandaj, Iran. P. O. Box 416. Tel: 98-188-723-563. E-mail: aminij2002@yahoo.com Received: March 30, 2012 Accepted: April 23, 2012 Online Published: July 11, 2012 doi:10.5539/jas.v4n8p199 URL: http://dx.doi.org/10.5539/jas.v4n8p199 Abstract Common and dwarf bunts are the most important diseases of wheat in the Kurdistan province, west of Iran. In this study, to investigate the reaction of wheat genotypes (grouped into two cold and warm season genotypes), they were evaluated for infection to common and dwarf bunts during 2007 and 2008 cropping seasons. Plant materials were groups of wheat genotypes included 82 and 158 genotypes from the cold and warm areas which were assessed in this study. For present study, wheat seeds were inoculated by common and dwarf bunts teliospores before planting, and sowing was accomplished during fall season of 2007 and 2008 at Ghamlou and Saral experimental stations. At maturity time, the percentage of infected heads and the main reactions were determined. Results revealed that resistance of genotypes to dwarf bunt was higher than common bunt and also bunt incidence of durum genotypes was relatively lower than bread wheat genotypes. The results demonstrated the existence of resistance gene analogues in durum wheat genotypes which could be used as donor progenitors. Replacement of durum wheat cultivars instead of bread wheat varieties could be an effective way in the developing of substantial farming. Keywords: assessment, common and dwarf bunts, wheat 1. Introduction The entire sown area of wheat in Iran is about 7,035,020 hectares (FAO, 2010), and around 550,057 hectares of land in the Kurdistan province has been allocated to the wheat production. In fact, in this district, wheat is the most important cereal for farmers to food supply and revenue creation. Diseases of wheat mostly caused by fungal pathogens and a few by viruses and bacteria which are important constraints in almost all wheat-growing areas (Rajaram & van Ginkel, 1996; McIntosh, 1998). In Iran, wheat crop is usually attacked by 15 different diseases at various stages of its growth. Among them, Smuts and rusts are the most important diseases of wheat especially in West and Northwest provinces (Akbari & Zolghadri, 1988). Although the amount of bunt's damage is less than rust wheat but because of its direct damage to wheat grains, decline in quality and quantity is more tangible. With regard to history of smut disease, we understand that since the beginnings of wheat cultivation by human bunts have been reduced yield and quality of wheat (Fisher & Holton, 1957). On the other hand, due to increased wheat monoculture and inappropriate use of seed chemical treatments epidemics have been became more common in small farms. Among smuts, common and dwarf bunt caused by T. laevis Kühn and T. controversa Kühn are the most serious disease of wheat around the world. Optimum infection of common bunt occurs when teliospore-laden seed is planted in soil at 5° to 10°C (Purdy & Kendrick, 1963). The distribution and incidence of dwarf bunt is highly