Ancestry of American polyploid Hordeum species with the I genome inferred from 5S and 18S-25S rDNA.

ABSTRACT:

Background and aims

The genus Hordeum exists at three ploidy levels (2x, 4x and 6x) and presents excellent material for investigating the patterns of polyploid evolution in plants. Here the aim was to clarify the ancestry of American polyploid species with the I genome. *

Methods

Chromosomal locations of 5S and 18S-25S ribosomal RNA genes were determined by fluorescence in situ hybridization (FISH). In both polyploid and diploid species, variation in 18S-25S rDNA repeated sequences was analysed by the RFLP technique. *

Key results

Six American tetraploid species were divided into two types that differed in the number of rDNA sites and RFLP profiles. Four hexaploid species were similar in number and location of both types of rDNA sites, but the RFLP profiles of 18S-25S

SUBMITTER: Taketa S 

PROVIDER: S-EPMC4246806 | biostudies-literature | 2005 Jul

REPOSITORIES: biostudies-literature