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The main objective of this study was to investigate the nature of farinograph absorption (FA) in CWRW flours which is typically lower than CWRS wheats. FA for CWRW genotype samples ranged from 54 - 65%. Phloroglucinol assay of pentosan content (PC) proved to be accurate and precise. The most highly correlated parameters to FA were volume fractions of large (or small) flour particles determined by laser diffraction, protein content, starch damage and water soluble PC. Correlations to FA for these factors were in the range r = 0.40 to 0.68. A promising 4-variable regression model of FA prediction (R2 = 0.64) was developed. CWRW wheats tended to be low in FA due to low levels of wheat hardness, protein content, or PC. Increasing the levels of these parameters by breeding would likely practically improve FA of future CWRW cultivars. An extended abstract is included at the end of this thesis.

The yellowness of flour colour ranges is an important quality trait in wheat for end-use products and is determined by the accumulation of carotenoids in the endosperm. The aims of this study were to develop EST-based molecular markers for genes encoding enzymes of the carotenoid biosynthetic pathway leading to xanthophyll accumulation and identify quantitative trait loci for flour colour (b*) and xanthophyll content in Western Australian adapted germplasm. A novel bioinformatic strategy was developed to identify rice genes encoding key enzymes of the carotenoid biosynthetic pathway and to predict wheat orthologues on the short arm of chromosome 3 or long arm of chromosome 7. The bioinformatic strategy involved the identification of rice carotenoid genes on BAC/PAC contigs aligned to wheat mapped ESTs. Rice genes predicted to have wheat orthologues were selected based on ESTs mapping to regions on wheat homoeologous chromosomes 3 and 7 known to be involved in flour colour. The rice genes predicted to have wheat orthologues were Geranylgeranyltransferase I ƒÒ¡Vsubunit (GGT-Ibeta) and Rab geranylgeranyltransferase component A (RGGT-A) on the short arm of chromosome 3, Lycopene ƒÒ¡Vcylcase (LBC) on the long arm of chromosome 3 and Lycopene £`¡Vcylcase (LEC) on the long arm of chromosome 7. The prediction of these wheat orthologues provided the basis for development of EST-based molecular markers for detecting variation in xanthophyll content. Wheat ESTs with unknown chromosomal locations and having the highest similarity to GGT-Ibeta, RGGT-A and LBC were selected for the development of molecular markers. No EST homologues were identified for LEC and therefore this gene was not further considered. Orthology was confirmed by sequencing and deletion lines were used to confirm chromosomal locations. Two partial orthologues of GGT-Ibeta were identified on the short arms of chromosomes 3B and 3D. A partial orthologue of RGGT-A was mapped to the proximal regions of the short and long arms of chromosome 3B. At least two or more orthologues of LBC were identified from nullisomic-tetrasomic lines. An EST-based molecular marker for GGT-Ibeta was found to be involved in minor variation of xanthophyll content in a Westonia*2/Janz doubled haploid population. QTL analysis from three doubled haploid populations indicated variation in WA-adapted germplasm may be due to different alleles controlling flour colour. QTLs for b* and xanthophyll content were found to coincide on the short arms of chromosomes 3A, 4D, and 7B and the long arm of chromosomes 7A and 7B in WA-adapted germplasm. Homoeologous expression of regions controlling variation in b* and xanthophyll content on the long arm of chromosomes 7A and 7B suggests the shut-down of genes in the same region on chromosome 7D. The main outcome of this study is flour colour and identification of gene orthologues in wheat controlling variation in xanthophyll content is complex most likely because of the interaction of the carotenoid biosynthetic pathway with other pathways.

Thesis (PH. D.)--University of Minnesota, 1922. / Biographical. Bibliography: p. 75-84. Also available in digital form on the Internet Archive Web site.

Thesis (Ph. D.)--University of Nebraska. / Includes bibliographical references (p. 38-39).

Thesis (Ph. D.)--University of Minnesota, 1926. / Biography. "Papers based on this thesis appeared in Cereal chemistry, v. 4, p. 230-247; 261-270." "Literature cited": p. 27-29.

Thesis (Ph. D.)--University of Minnesota, 1928. / Biography. "Literature cited": p. 77-78.

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xvii, 164 p. : ill. (some col.). Advisor: Yael Vodovotz, Department of Food Science and Technology. Includes bibliographical references (p. 149-164).

Thesis (Ph. D.)--University of Nebraska. / Includes bibliographical references (p. 38-39).

Thesis (Ph. D.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 209-231).