Comparison Of Genetic Diversity Of Monomeric Prolamins In Wild Close Relatives Of Barley From Tibet Of China

Tibet has become a representative area for barley in the world, on account of it especial environments, climate conditions and ancient cultivated history of barley, and supplied very ample colorful genetic resources of barley for the research of the world. Tibetan wild close relatives of barley is one of the most precious germplasm resources in Qinghai-Tibet Plateau, and is very important for the research about the origin, evolution, classification, and the application of barley resources.Prolamins, the proteins soluble in aqueous alcohol solutions in the seeds of cereals, are the major storage protein components of most cereal seeds and account for about 40%-60% in the nitrogen content of aged seeds. In wheat, prolamins include gliadin (a monomeric protein) and polymeric glutenin. The research in the past always used "hordein" to denote the prolamins in barley, which is only the polymeric prolamin. The present study was carried out use monomeric prolamims (protein fraction corresponding to wheat gliadins). Furthermore, few data on monomeric prolamims of barley in Tibet have been seen.. This study used monomeric prolamins as genetic markers and SDS-PAGE to analyze the diversity of 380 wild barley accessions, including 330 accessions from Qinghai-Tibet plateau (ZYM) and 50 accessions from other countries (WYM) in Middle East. From the results, we obtained 134 different band patterns: 91 out of 330 ZYM accessions and 43 out of 50 WYM accessions. Totally, 42 bands with different positions in the gel, from negative pole to positive pole in order of decreasingmobility, were identified: 40 bands in ZYM and 37 in WYM. From the distribution and percentage of the band per accession, we could see that the genetic diversity of ZYM accessions is higher than that in WYM. According to the H and Gst of 42 bands and the dendrogram clustered by program of 134 band patterns, the ZYM accessions have a higher genetic diversity than that in WYM, although WYM accessions have their own diversity region and special band. Our results show that the genetic diversity of monomeric prolamins in wild close barley from Qinghai-Tibet plateau is very abundant.The analyses of our results give more evidence to support the hypothesis that Tibet is one of the diversity centers and origin centers of barley in the world.