| Barley belongs to Gramineae, Hordeum. Barley is of major commercial importance as a cereal grain, used as fodder crop and for malting in beers. In a 2007 ranking of cereal crops in the world, barley was fourth both in terms of quantity produced (136 million tons) and in area of cultivation (566,000 km2). Barley has many uses. It serves as a major animal fodder, as a base malt for beer and certain distilled beverages, and as a component of various health foods. It is used in soups and stews. It is a self-pollinating, diploid species with 14 chromosomes. Barley is a widely adaptable crop. It is currently popular in temperate areas where it is grown as a summer crop and tropical areas where it is sown as a winter crop. Barley is more tolerant of soil salinity than wheat。Wild barley (Hordeum spontaneum) were considered the ancestors of cultivated barley. In the Middle East region, Turkey, and Afghanistan, It had broad distribution. Wild barley is important genetic resources for improvement of barley varieties. Wild barley is considered the 21st century an important genetic resource for crop improvement.In this study, we selected 2 wild barley populations that come from Mehola and Mt.Gilboa Israel. In addition,18 cultivars from different countries all of the world were used. We compared between wild barley and cultivated barley s genetic diversity. We used SSR markers, Intron-splice junction primer-ISJ markers, hordeins and agronomic to analyze genetic diversity in this study. Main conclusions are as follows:(l)With 35 pairs of SSR primers, the genetic diversity in two wild barley populations and cultivars showed:35 pairs of primers total amplified 114 bands.86 bands were polymorphic, percentage of polymorphic bands was 75.43%. Each primers PIC value between 0.42-0.94. Mehola populations hold higher genetic diversity than Mt.Gilboa population. The proportion of polymorphic bands accounted for 70.68%, average genetic diversity index was 0.3312. Another group of wild barley Mt.Gilboa proportion of polymorphic bands up to 67.41%, genetic diversity index was 0.3159. Between wild barley and cultivated barley, the genetic diversity index was 0.3651. Between wild barley and cultivated barley the genetic similarity coefficient was 0.6372. Analysis showed that wild barley genetic diversity among populations higher within populations. Between wild barley and cultivated barley have a more extensive genetic diversity. Cluster analysis showed wild barley and cultivated barley can be completely separate, two wild barley populations were also distributed to different groups. We also found, similar code number of wild materials distribution close in clustering. The geographical distribute closely in the cluster diagram. Cluster distribution and the geographical source of material to a certain extent.(2) By nine intron-splice junction primer and 5 Combination of long random primers, analyzed genetic diversity for two groups of wild barley and 18 varieties. Received 115 bands by PCR amplified. Polymorphism number was 76. Polymorphism rate was 66.67%. E2,E4,R1,R3 could amplified more bands compared with other primers. Their amplified bands rang 8-13. The genetic similarity coefficient ranged between 0.207-0.956. By cluster analysis, wild barley and varieties were divided into two groups. Two wild populations were significantly separated.(3) Analysis of hordein s genetic diversity for wild barley and cultivated barley found that four interval was rich in genetic diversity. Theωarea has higher frequency than other three area. Theωin cultivated barley frequency was 54%.in wild barley this area theωoccurred frequency was 61%.In wild barley genetic diversity of hordein,from high to low as the order:ω>β>α>γ. In cultivars in the order:β>ω>a>y. The genetic similarity coefficient between wild barley and cultivated barley was change in 0.235-0.941. Wild barley and cultivated barley existence considerable genetic diversity.(4) Analyzed six major agronomic traits in wild barley and cultivated barley for genetic diversity found, between wild barley and cultivated barley in six major agronomic traits existence of higher genetic diversity. Analysis of variance showed that plant height, kernel weight, grain number, tiller number, awn length, spike length reached the significant level, plant height, tiller number, grain number was significantly higher than other traits, and to a significant level. The coefficient of variation (CV) between wild barley and cultivars ranged 0.06-0.36. Grain number and tiller number have higher genetic variation coefficient, between 0.28-0.36. Note that two traits susceptible to environmental and poorly stability in genetics. Plant height, spike length and awn length have lower coefficient of variation, indicate these traits not easily affected by environment factors, also have more stable genetic mechanism. According to different agronomic traits by cluster analysis, wild barley and cultivated barley can be clearly separated, and wild barley is divided into two basic groups. In addition code number similarly of materials distribution closely in clustering. These materials have same or similarly geography, which in clustering distribution nearly. This showed that materials geographic have some certain effect on cluster result.
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