Molecular evaluation of 1RS-rye translocation distribution in the Iranian dryland wheat cultivars and elite promising lines

Abstract

The short arm of 1RS rye (Secale cereale L.) chromosome carrying genes involved in resistance to biotic and abiotic stresses provided a valuable source in developing new bread wheat (Triticum aestivium L.) cultivars resilient to stressed environments. The 1BL.1RS and 1AL.1RS translocations have been utilized in wheat breeding programs on a global scale. In this study, three rye specific primers (RyeR3/F3, PAW161 and O-SEC5’-A/O-SEC3’-R) were applied to investigate the distribution of 1RS arms in 22 dryland promising wheat genotypes, 7 dryland commercial wheat cultivars (Azar2, Ohadi, Rasad, Sabalan, Karim, Rijaw and Homa) and three genotypes with international origin (Seri82, 21thFW-236, and 21thFW-244) along with positive and negative controls to verify the results. 1RS arm presence was confirmed in the 86% of Iranian dryland promising lines and wheat cultivars. Using O-SEC5’-A/O-SEC3’-R primer none of the examined Iranian dryland wheat lines and cultivars was found to carry 1AL.1RS translocation. In this study Rye specific markers proved effective in the successful detection of wheat cultivars carrying 1RS arms and application of MAS in identifying wheat genotypes tolerant to environmental stresses. A high frequency of 1BL.1RS translocation was detected in the dryland promising wheat lines as well as in the commercial dryland wheat cultivars. This finding suggested the need for diversifying resistance gene sources by introducing the 1AL.1RS translocation into Iranian wheat germplasm. Genetic diversity revealed here, may be explored for developing new wheat cultivars with enhanced level of adaptation to adverse environmental conditions.