Thesis (Ph. D.)--Washington State University, August 2009. / Title from PDF title page (viewed on Aug. 24, 2009). "Department of Molecular Plant Sciences." Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1980. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 129-134).

Thesis (doctoral)--Universität Bern, 1900. / Includes bibliographical references.

The present study has been initiated to investigate the genetical and environmental factors affecting the protein content of white haricot beans. A study of this nature requires the use of crude protein and methionine techniques to analyse large numbers of plant lines quickly and efficiently. Two techniques are considered suitable for estimating percentage crude protein - the Kjeldahl-Markham technique for limited numbers of samples and the automated nitrogen analyser for the large numbers of breeding samples. A microbiological method has been chosen for the analysis of available methionine. These protein and methionine techniques are then used to assess the genetic variation in the collection of white haricot beans. From this collection, twenty five varieties have been selected and assessed in Variety Trials over four different seasons to estimate the environmental effects on protein and methionine content. There is a considerable environmental effect on protein content and no effect on methionine content. In the light of this environmental effect on protein content, the effect of different levels of fertiliser treatment are considered. The results show a significant variety x fertiliser treatment interaction for protein content, but not for methionine content. The protein-yield relationship has also been considered in relation to the increasing levels of fertiliser and the results show considerable variation according to the type of growth habit of the variety. The results indicate that for the protein inheritance study, it is important to grow all generations in one season and under as near to possible uniform environmental conditions. A quantitative genetical approach to the study of protein inheritance has been adopted, using F1, F2 and F3 generations of 7x7 non reciprocal diallel of selected contrasting parents. The genetic control of protein content has been studied using diallel cross analysis of Jinks and Hayman and the interpretation is based on the graphical presentation of the results of the analysis. The results suggest that protein content is controlled by a series of genes with minor effects which are additive but with partial dominance for low protein in at least some of the loci. An assessment of the potential of the varieties has been made on the basis of their general and specific combining ability for protein. The results obtained from the various aspects of the study are discussed in relation to the improvement of the bean crop.

A 12S glycoprotein was isolated from commercial rapeseed meal (Brassica campestris) and examined by chemical, microscopical, and rheological methods. The molecular weight of the protein was estimated to be 129,200 daltons by conventional sedimentation equilibrium ultracentrifugation although the presence of higher molecular weight material was detected in the preparation. The 12S protein was found to be oligomeric, dissociating, into low molecular weight fragments in the presence of urea or sodium dodecyl sulfate. The protein aggregate was separated into subunits with apparent molecular weights of approximately 42,000, 37,600, 30,100, 17,400 and 12,200 by SDS gel electrophoresis. Electrophoretic patterns of non-reduced and reduced samples indicated the presence of intermolecular disulfide bonds although the cystine content was low. The 12S protein contained 12.9% (w/w) carbohydrate and reacted strongly when oxidized and treated with Schiff reagent. PAS-treated SDS gels indicated that most of the carbohydrate was present in one low molecular weight fragment. SDS immunoelectrophoretic analysis suggested that the glyco-peptide portion is located on the surface of the complex. Although the isolate contained a high molecular weight contaminant (17S), immunoelectrophoretic analysis resulted in the formation of one homogeneous pair of precipitin arcs. This would suggest that the 12S protein self-associates to form aggregates of higher molecular weight. In an attempt to separate the 17S and 12S fractions by gel filtration, a 33.9S protein was isolated, presumably the product of a self-associating system. SDS electrophoretic patterns of the 33.9S and 12S proteins were similar. Histochemical studies revealed that the 12S glycoprotein was present in some but not all of the cells of the intact rapeseed kernel. Schiff-positive aleurones were distributed randomly throughout the kernels. Transmission electron microscopy of negatively-stained specimens revealed that the protein was morula-shaped with a maximum particle diameter of 120Å The 12S rapeseed protein formed gels when dispersions of this material were heated. The rheological and ultra-structural examination of this phenomenon revealed that gel structure depended upon pH and ionic strength but to a lesser degree on low levels of urea or dithiothreitol. / Land and Food Systems, Faculty of / Graduate

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published_or_final_version / Botany / Doctoral / Doctor of Philosophy

by Feng Zhang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1988. / Bibliography: leaves 104-115.