Genetic control of cold hardiness using generation mean analysis in bread wheat (Triticum aestivum L.em Thell)

Low – temperature (LT) tolerance in wheat is a quantitative character that is regulated by a complex arrays of genes. Although several genetic studies have been conducted , there is not a general consensus on the mode of gene action. The objective of the present study is to determine the mode of gene action and inheritance of cold tolerance genes(LT50) in winter × spring cross of bread wheat. In this study ‘Mironovskaya 808808' as tolerant (winter habit ) was crossed with ‘Pishtaz' as sensitive parent (spring habit) and F1 , F2 , BC1 (back crossed to spring parent) , BC2 (back crossed to winter parent) and F2 generations were evaluated for freezing test. In this study it clarified that cold tolerance in wheat is controlled by additive, dominant and also epistatic genes. Overall, the number of genes related to cold tolerance in wheat estimated between 1 to 6. According to different methods, the broad sense (h2BS ) and narrow sense heritabilities (h2NS) were 0.89 and 0.61 respectively. The h2BS shows that transmission of cold tolerance trait from tolerant to sensitive cultivars in breeding programs is possible.