Identification For Crown Rot Resistance Of Triticeae Crops And The Genetic Diversity Of Barley Varieties From Different Countries

Barley, Hordeum vulgare L., is not only one of the principal cereal crops for the malting and brewing industry as well as feed for animal husbandry in the world, but also an established model species for genetic and physiological studies. Wild barley (H. spontaneum) is the progenitor of cultivated barley and is widely distributed over the eastern Mediterranean rim and west Asia, with the majority of the primary and secondary habitats in the Jordan Valley. The centre of diversity for wild barley and the primary site of domestication are considered to be the Fertile Crescent of the Near East. Wild barley possesses a high genetic diversity, and many alleles are associated with specific environment. In this study the wild barley from Mt. Gilboa and Mehula, Israel and cultivars from all around the world were subjected to analysis. In chapter two we studied the crown rot disease resistance of wild barley and cultivars and some wheat mainly from the Middle East. In chapter three we used molecular markers SSR and ISJ studies the genetic diversity of two wild barley populations from Mehula and Mt. Gilboa, Israel and representative cultivars from around the world. The main results are as follows:(1) The total of 169 wheat and 192 barley germplasm resources were evaluated for resistance to crown rot by inoculating spore suspension in seedling stage. There were 43 wheat resistant materials, the resistance accessions accounted for 25.44%, including 6 common wheat, 17 triticale, 7 durum wheat and 13 wild wheat materials. Barley identified 88 resistant materials, accounted for barley test materials 45.60%, including 11 cultivated barley, 33 barley landrace and 44 wild barley materials. Anglicizing showed that in all the tested materials, the proportion of resistant material in cultivars and local varieties than the wild materials larger; the proportion of resistant materials in barley is lager than wheat materials. However, the resistance of cultivars are general, while wild material was identified a number of excellent resistant materials. This study indicated that resources had resistant genes which had a potential value to crown rot resistance breeding, and also provides a theoretical basis for study the loss of genetic diversity in crop evolution.(2) Wild barley has been considered to be a large reservoir of genetic diversity and represents the primary gene pool of cultivated barley. The genetic diversity between one natural population of wild barley and barley varieties from different countries were investigated using PCR (Polymerase Chain Reaction) analysis with intron-splice junction (ISJ) primer and SSR primers. The result of this study suggests that the level of genetic diversity of one natural population of wild barley is much higher.