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ARS Home » Pacific West Area » Logan, Utah » Forage and Range Research » Research » Publications at this Location » Publication #339621

Research Project: Develop Improved Plant Genetic Resources to Enhance Pasture and Rangeland Productivity in the Semiarid Regions of the Western U.S.

Location: Forage and Range Research

Title: Characterization of St and Y genome in StStYY Elymus species (Triticeae: Poaceae) using Sequential FISH and GISH

Author
item LIU, RUIJUAN - Chinese Academy Of Agricultural Sciences
item Wang, Richard
item YU, FENG - Chinese Academy Of Agricultural Sciences
item LU, XINGWANG - Chinese Academy Of Agricultural Sciences
item DOU, QUANWEN - Chinese Academy Of Agricultural Sciences

Submitted to: Genome
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/23/2017
Publication Date: 6/30/2017
Citation: Liu, R., Wang, R., Yu, F., Lu, X., Dou, Q. 2017. Characterization of St and Y genome in StStYY Elymus species (Triticeae: Poaceae) using Sequential FISH and GISH. Genome. 60:679-685.

Interpretive Summary: The taxonomy and nomenclature of the tribe Triticeae, which contains many important North American and Asian cool-season forage grasses, has been and continues to be in a state of uncertainty. This problem is especially great for the genus Elymus, which is comprised of taxonomic allopolyploids with many genome combinations. This problem makes breeding forage grasses of the Elymus species difficult if their genetic make-ups are unknown. To differentiate St and Y genomes, chromosomes in 10 Elymus species were characterized using FISH (fluorescence in situ hybridization) and GISH (genomic in situ hybridization). Based on the molecular karyotypes of these 10 species, eight of them had the typical pattern for StY genome constitution. Elymus alashanicus and E. longearistatus were different from typical StY species; thus, further studies using other techniques are needed to ascertain their genome constitution.

Technical Abstract: Tetraploid species possessing StY genome could be donors to hexaploid species having StYH, StYP, or StYW genome constitution in the genus Elymus, and a few of StY species have been intensely studied for inferring the origin of the Y genome. In this study, genome characterization of St and Y genome was conducted in 10 StY Elymus species using FISH (fluorescence in situ hybridization) and GISH (genomic in situ hybridization). Ten tetraploid species were distinctly grouped into 3 types: putative StY species including Roegneria sinica, R. pendulina, R. nutans, R. glaberrima, E. nevskii, R. breviglumis, R. dura and R. ciliaris, whose genome could be separated into two sets by differentiated GISH intensity; Elymus. alashanicus, whose genome was easily separated by GISH pattern; and E. longearistatus, whose genome was difficult to be separated by GISH. The St genome was distinctly different from the Y genome with distribution patterns of 5S rDNA and 18S-26S rDNA sites, and pAs1 hybridization intensity, although genome differentiated were still detected among the different StY species. Comparative cytogenetic analysis did not apparently show that the studied StY genome might be a candidate donor genome to those StYH, StYP, and StYW species. Genome constitution of E. alashanicus was suggested as a modified St genome and an unknown genome. Genome in E. longearistatus was greatly varied and needs more investigation.