ASSESSMENT OF THE GENETIC DIVERSITY OF GLUTENINS BY SDS-PAGE METHOD REVEALS PRIVATE SUBUNITS IN WHEAT PROGENITORS AND LANDRACES FOR BREEDING PURPOSES

Wild relatives and landraces are still considered valuable sources to improve beneficial traits for crops breeding purposes. In the present study, the variation of glutenin proteins was assessed for 120 accessions of Triticum, Aegilops genus, landraces and cultivated bread wheat and durum wheat varieties using Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoretic (SDS-PAGE) method. High and Low molecular weight glutenin subunits displayed a far greater variation in the accessions, as 38 and 135 alleles were identified respectively. The wide range of glutenin subunits variation has the potential to enhance the genetic variability for improving the quality of wheat. AMOVA showed that the molecular variance among populations (34%) was lower than within populations (66%). According to Nei genetic distance, cluster tree and Jaccard’s coefficient analysis, the bread and durum wheat varieties groups were the most distant from the other groups of wild relatives and landraces with similarity values ranging from 0.745 to 0.89. All the groups performed high polymorphic patterns and relatively low heterozygosity levels due to the dominance of specific bands. The highest diversity levels were in landraces (78) and Aegilops genus (68). On the other hand, the lowest levels of diversity were found in durum and bread wheat varieties groups (22 and 29 respectively) confirming the reduced genetic diversity due to the selection pressure of breeding programs. These results provide the possibility for further research aiming to investigate the effects on quality traits of the described variation, including the specific effects of rare and novel alleles, and their usefulness for cultivars improvement.