Wild barley (Hordeum vulgare subsp. spontaneum) could be a source of useful
genes for improving cultivated barley. The useful genes present in Hordeum
vulgare subsp. spontaneum may be new alleles at described loci, or these may be
entirely new genes in the sense that there is limited allelic variation at these loci in
the cultivated germplasm pool. This research was directed at gene discovery in wild
barley and involved two steps: (i) characterization of diversity using genetic
markers and (ii) development and characterization of novel germplasm for gene
discovery.
Simple Sequence Repeats (SSRs) of known map location were used to survey three
representative groups of barley germplasm: a sample of crop progenitor (Hordeum
vulgare subsp. spontaneum) accessions, a group of mapping population parents,
and a group of varieties and elite breeding lines. The objectives were to determine
the informativeness and utility of SSRs in differentiating and classifying the three
sets of barley germplasm. Crop progenitors had the highest number of alleles per
SSR locus, followed by mapping population parents and elite breeding lines. The
cluster analysis indicated a high level of diversity within the crop progenitor
accessions and within the mapping population parents. It revealed a much lower
level of diversity within the elite breeding germplasm.
A set of Recombinant Chromosome Substitution Lines (RCSLs) representing
introgressions of Hordeum vulgare subsp. spontaneum genome in to a cultivated
barley background were developed using the Advanced Backcross strategy. An
accession of Hordeum vulgare subsp. spontaneum was the donor parent and the
variety "Harrington" was the recurrent parent. The RCSLs were developed via two
backcrosses to the recurrent parent followed by six generations of selfing. The
genomic architecture of the RCSLs was determined by molecular marker
fingerprinting with SSRs. The consequences of introgressions of Hordeum vulgare
subsp. spontaneum genome segments into the recurrent parent were assessed in
terms of inflorescence yield components, malting quality traits, and domestication-related
traits. Hordeum spontaneum subsp. spontaneum, despite its overall inferior
phenotype, contributed favorable alleles for some characters of agronomic
performance. In other cases, the introgressions caused a disruption of the
Harrington phenotype, a "reverse genetics" approach to gene discovery. / Graduation date: 2003
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/31493 |
| Date | 19 December 2002 |
| Creators | Matus, Iv��n Ariel |
| Contributors | Hayes, Patrick M. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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