فاطمه محمدی آذر - Department of Agronomy and Plant Breeding, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran.
امید سفالیان - Department of Agronomy and Plant Breeding, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran.
علی اصغری - Department of Agronomy and Plant Breeding, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran.
اصغر عبادی - Department of Agronomy and Plant Breeding, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran.
رحمت اله کریمی زاده - Gachsaran Agricultural Research Institute, Kohgiluyeh and Boyerahmad Agricultural and Natural Resources Research and Education Center, Gachsaran, Iran.

Cold tolerance in wheat is one of the most important factors effective in the field of winter damage in Iran. Freezing and laboratory tests were carried out in the greenhouse and plant breeding laboratory of Mohaghegh Ardabili University in ۲۰۱۸-۲۰ to achieve the set goals. The plant materials used included ۴۵ promising durum wheat lines. Durum wheat genotypes were planted in a randomized complete block design with three stress levels. The results of the variance analysis of LT۵۰ showed a significant difference between the genotypes at the probability level of ۱%. LT۵۰ varied between -۰.۷۵۴ and -۲۶.۶۰۹ values. The survival percentage of plants decreased with increasing stress. In clustering based on the LT۵۰, the genotypes were divided into ۵ groups. The dendrogram obtained from the cluster analysis based on all the traits divided lines in the control level, -۸ °C, -۱۰ °C, and -۱۲ °C into ۸, ۶, ۹ and ۷ different groups. Four factors were identified in the control level, ۵ in the first stress, ۶ in the second stress, and ۵ in the third stress level. To evaluate the relationship between the measured traits and RAPD molecular markers, stepwise multiple regression analysis was performed and significant relationships were observed. LT۵۰ showed a correlation with ۹ markers. Finally, according to the tests conducted, lines ۱, ۲, ۳, ۴, ۵, ۶, ۷, ۸, ۱۰, and ۲۳ were recognized sensitive lines and lines ۱۱, ۱۲, ۱۳, ۱۴, ۱۵, ۱۷, ۱۸, ۱۹, ۲۱, ۲۹, ۳۱ and ۲۷ were recognized as resistant.

durum wheat, freezing stress, LT۵۰, Molecular marker