Development Of EST-SSR Markers And Analyses Of Genetic Diversity In Siberian Wildrye(Elymus Sibiricus L.)

Siberian wildrye(Elymus sibiricus) is a perennial, self-fertilizing and allotetraploid(StStHH) grass that plays an important role in the development of animal husbandry and environmental sustenance, because it not only has the characteristics of good palatability, high yield, rich in nutrients, and high digestibility, but possess the excellent cold and drought tolerance. However, the transcriptomic and molecular marker information of E. sibiricus is still very limited due to the late start of related study, which severly hindering its use in germplasm resources and genetic breeding studies of E. sibiricus. 11 different E. sibiricus tissues were collected in the present study, such as callus cells, radicles and seedlings, and the total RNA from 11 samples was isolated and pooled equally to construct the cDNA library, which was sequenced using the Illumina Hiseq2000 sequencing platform. According to the transcriptome data of E. sibiricus which was obtained after sequencing, a total of 112 polymorphic primer pairs were developed. Moreover, these 112 polymorphic primer pairs were used to evaluate the transferability to 13 other related species. The main results were as follows:1. A total of 6.90 G data were generated from 11 different tissue samples of E. sibiricus by Illumina paired-end sequencing, and the NCBI registration number is SRX574376. And 8,769 potential EST-SSRs were identified from 94,458 unigenes sequences using the MicroSatellite program, which were obtained by de novo assembly, and 1,078 primer pairs were successfully designed.2. Among 1,078 successfully designed primer pairs, 500 pairs were randomly selected and synthesised to assess polymorphisms in 15 E. sibiricus accessions, and each accession contains three individual plants. As a results, a total of 112 primer pairs were polymorphic, and the polymorphism information content(PIC) values ranged from 0.39 to 0.81.3. These 112 polymorphic primer pairs were used to evaluate the transferability to 13 other related species, such as E. abolinii and E. antiquus, and 55 EST-SSR markers were found to be polymorphic among these 13 Elymus species.The present research is the first time to explore the transcriptome data of E. sibiricus in the world and developed some species-specific EST-SSR molecular markers, which was used to study the genetic characteristics of different E.sibiricus germplasms and Elymus species. This study powerfully promoted the genetic diversity and molecular-assisted breeding studies of E. sibiricus and Elymus species, which has laid an important foundation for the study of molecular biology of E. sibiricus.