Comparison of Genetic Diversity Level Between European and East-Asian Wheat Collections Using SSR Markers

International audience; 【Objective】This research work was performed to reveal the genetic relationship and diversity difference between European and East-Asian wheat cultivars, and in the meantime to compare the level of polymorphism between Genomic-SSRs and EST-SSRs. 【Method】 To analyze 371 European and 363 East-Asian wheat collections, 38 Genomic-SSRs and 44 EST-SSRs were used. 【Result】A total of 865 alleles were detected, with a range from 1 to 50 and a mean of 10.42. Polymorphism information content (PIC) ranged from 0 to 0.91 with an average of 0.53. Genetic diversity level in East-Asia was higher than that in Europe. European and East-Asian accessions were divided into two distinct sub-groups by PCO based on 82 SSRs. The position of materials in the dendrogram was accordant with their geographical location, i.e. the accessions from near geographical location were joining into neighbors. Allele differentiation between the two continents at some loci such as Xgwm186, Xgwm257, Xgpw7433 andXgpw7443 was very significant. This may be corresponding to the natural and breeding selection, which was supported by the marker/trait association analysis results. Chinese varieties released from 1950 to 1980 were clustered into one big group with Europeans, and far away from native landraces and varieties released before 1950. This is consistent with the records of wheat breeding history of China. Diversity revealed by Genomic-SSRs was much higher than that by EST-SSRs. However, the cluster trend based on the two types of SSR was consistent. Therefore, differentiation of Genomic-SSR was much faster than functional genes SSR in breeding selection. 【Conclusion】European germplasms can be efficiently used in Chinese wheat breeding program through backcross breeding method.