Dissertation
CLASSIFICATION OF SOFT DURUM WHEAT (Triticum turgidum subsp. durum) AND GENETIC ANALYSIS OF END-USE QUALITY TRAITS IN HARD RED SPRING WHEAT (Triticum aestivum L.) USING A GBS APPROACH
Doctor of Philosophy (PhD), Washington State University
01/2017
Handle:
https://hdl.handle.net/2376/112505
Abstract
Wheat (Triticum aestivum L.) is a worldwide staple crop, with distinct market classes and culinary end-uses that are in part determined by its kernel texture characteristics. ‘Soft Svevo’, a new durum cultivar (Triticum turgidum subsp. durum) featuring soft kernel texture, was developed by the Ph1b-mediated homoeologous transfer of the Puroindoline genes at the Hardness (Ha) locus from the D genome of Triticum aestivum. Our first objective was to classify the size of the 5DS-5BS ‘Chinese Spring’ translocation present in Soft Svevo. Genotyping of near-isogenic pairs of hard and soft durum wheats and subsequent BLASTn results for tagged markers indicate the 5DS-5BS translocation was nearly reciprocal, as a ~24.36 Mbp terminal distal segment of chromosome 5DS was gained, whereas a ~20.01 Mbp terminal distal segment of chromosome 5BS was lost. Our second and third objectives were to classify the end-use quality of 46 new soft durum wheat lines relative to soft and hard wheat end-use quality traits. Results revealed that the soft durum lines had high break and total flour yield, low starch damage, and cookie measurements similar to that of soft wheat checks, but that the gluten strength, gluten quality and pup loaf volume did not compare favorably to hard wheat checks. Our fourth objective was to identify new QTLs for 16 end-use quality traits in a set of 132 hard red spring wheat RILs segregating for Puroindoline alleles at the Ha locus, and high and low molecular weight glutenin alleles at the Glu-A1, Glu-B1, Glu-A3, Glu-B3 and Glu-D3 loci. Multiple QTL mapping performed in rQTL identified 29 major QTLs explaining greater than 15% of the phenotypic variance each, with 10 of those being reported for the first time. The classification and development of new soft durum germplasm will serve to broaden durum wheat’s end-use functionality and help in determining a market fit for new commercial applications. Moreover, the discovery of the major end-use quality QTLs being reported herein will improve forward genetics breeding strategies via the implementation of GBS markers for the selection of favorable end-use quality alleles in newly developed hard red spring wheat cultivars.
Metrics
26 File views/ downloads
53 Record Views
Details
- Title
- CLASSIFICATION OF SOFT DURUM WHEAT (Triticum turgidum subsp. durum) AND GENETIC ANALYSIS OF END-USE QUALITY TRAITS IN HARD RED SPRING WHEAT (Triticum aestivum L.) USING A GBS APPROACH
- Creators
- Jeffrey David Boehm Jr.
- Contributors
- Craig F Morris (Advisor)Michael O Pumphrey (Advisor)Kimberly A Garland-Campbell (Committee Member)Michael M Neff (Committee Member)
- Awarding Institution
- Washington State University
- Academic Unit
- Department of Crop and Soil Sciences
- Theses and Dissertations
- Doctor of Philosophy (PhD), Washington State University
- Number of pages
- 228
- Identifiers
- 99900581828101842
- Language
- English
- Resource Type
- Dissertation