Genetic diversity of Acid-PAGE monomeric prolamins in cultivated hulless barley (Hordeum vulgare L.) from Qinghai-Tibet plateau in China

Naked barley, due to its favorable attributes such as high feed value, good human nutrition and easy processing, increasingly attracts people's attention. Qinghai-Tibet Plateau is very rich in naked barley resources and has a long growing history. Genetic diversity of these cultivated naked barley is, however, poorly documented. This study analyzed the genetic diversity of monomeric prolamins (protein fraction corresponding to wheat gliadins) using the Acid -PAGE technique in eighty-six cultivated naked barley cultivars from Qinghai-Tibet Plateau. Extensive diversity was observed. A total of 43 different bands and 76 distinct patterns were found. Jaccard's coefficient of similarity was calculated, and the accessions were divided into five main groups by cluster analysis using UPGMA. Differentiation among the populations from different collecting regions was investigated, based on the polymorphism of monomeric prolamins. The genetic diversity within the accessions from Tibet was slightly higher with an average diversity index of 0.29 than those from Sichuan. This study supports Tibetan Plateau is the diversity center of the cultivated naked barley and suggests that cultivated naked barley from Qinghai-Tibet Plateau is an important pool of variability that could be used in cereal breeding.