Graduate Thesis Or Dissertation
 

Nuclear and chloroplast diversity of Pacific Northwest wheat (Triticum aestivum) breeding germplasm

Public Deposited

Downloadable Content

Download PDF
Request Accessible Version
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/hd76s314t

Descriptions

Attribute NameValues
Creator
Abstract
  • Wheat breeders must effectively maintain and manage existing genetic diversity in order to continue the development of superior genotypes. It is therefore fundamental that the genetic relationships and diversity within the germplasm pools be thoroughly characterized and understood. Recently, DNA-based markers have provided powerful tools for genetic diversity analysis. This study investigates the usefulness of nuclear and chloroplast simple sequence repeat (SSR) markers in characterizing Pacific Northwest wheat (Triticum aestivum) breeding germplasm, and explores the patterns of genetic relatedness revealed by these markers. The 15 chloroplast SSRs were effective in differentiating between B-type, D-type, and barley (Hordeum vulgare) cytoplasms. Genetic distance estimates were determined for each pair of lines studied and analyzed using UPGMA clustering. The markers revealed five plastomic types within the B-type cytoplasm studied. Several lines of wheat in this germplasm, including important PNW cultivars like Madsen, were found to contain D-type cytoplasm rather than the B cytoplasm of wheat. Nuclear SSR assays using 24 markers revealed three major clusters of germplasms: PNW soft white winter wheat, Western European-derived lines, and Great Plains accessions, as well as two clusters of more distantly related lines and genetic stocks. The primary defining characteristic of these clusters was regional adaptation. Subgroups of these major groups often clustered together on the basis of pedigree and market class. When nuclear and chloroplast SSR data was combined in analysis, the primary defining characteristic of the dendrogram became the type of cytoplasm rather than regional adaptation, with secondary divisions based on pedigree relationships. Cultivars released prior to 1950 were found to have a minimum of 20% of alleles in common for nuclear and chloroplast data combined, despite being unrelated via pedigree information. Heterogeneity was 2.3% for all marker/variety combinations. Overall, these sets of markers were found to be effective in characterizing the genetic relatedness of PNW wheat breeding germplasm.
License
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome) using Capture Perfect 3.0.82 on a Canon DR-9080C in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces
Accessibility Feature

Relationships

Parents:

This work has no parents.

In Collection:

Items

Thumbnail Title Date Uploaded Visibility Actions
file details EdwardsMelanieL2003.pdf 2017-08-15 Public Download