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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Separation and identification of the host, mycelial and conidial metabolites of powdery mildewed barley

Edwards, Harold Herbert, January 1965 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1965. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.
22

The inheritance of barley kernel color using the Agtron, the Hunter Color Difference Meter, and visual scores

Daniel, Gregory Paul, January 1976 (has links)
Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 144-149).
23

Height and other plant character inheritance in barley crosses made for shorter-strawed types

Barker, LeRoy N., January 1964 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1964. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Bibliography: leaves 139-145.
24

Variance components and linkage effects in two barley crosses

Vande Logt, Michael Bernard. January 1978 (has links)
Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 53-56).
25

Factors affecting barley kernel weathering and response of hybrid progenies in early generations

Salm, Peter A. January 1965 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 63-65.
26

Selection for harvest index in spring barley (Hordeum vulgare L.)

Osman, Mohamad Bin. January 1984 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 102-109).
27

The inheritance of spike nodding angle in spring barley

Miller, Jay Paul. January 1980 (has links)
Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 52-54).
28

Physiology and genetics of the kernel color of barley.

Faris, Donald George January 1955 (has links)
The generally accepted trademark of Canadian malting barley varieties is "blue" aleurone color in the kernel. New Canadian feed barley varieties are preferably marked by a "white" aleurone color. In attempting to meet the color qualifications in new introductions, Canadian barley breeders have often experienced difficulty in separating genetically "blue" from genetically "white" seed. An attempt has been made in this thesis to extend the knowledge on the inheritance, physiology, and separation of "blue" and "white" barley varieties. "Purple" and "black" barley kernel colors were also studied. Crosses were made between twenty barley varieties in an attempt to ascertain the inheritance patterns for kernel color. The study of color inheritance in the kernel acted as a background for physiological, histo-chemical, and chromatographic experiments. The physiological studies of color development in barley plants and caryopses made use of three barley varieties, "Smyrna" (white), "Awnless" (blue), and "Black Hulless" (purple). These three varieties were fed complete, low N, and low P solutions and were divided equally into the five following treatment blocks: "control", "ultra-violet", "infra-red", "dextrose" and "low temperature". The most consistent increase in plant and seed color development was associated with the low N and low P nutrient levels. There was a ""barely significant" difference in color development between the five treatment blocks. Dry and sprouting kernels of "white" and "blue" seeded barley varieties were examined under natural, colored, and ultraviolet lights. The most consistent difference between seed of the two color types was found when dry seed was observed under a dissecting microscope in natural light. Histo-chemical examinations of colored kernels showed that the coloring pigments were localized in the aleurone and pericarp layers. The blue and the purple pigments, located in the aleurone and pericarp layers respectively turned red when placed in cold conditions. Under alkaline conditions the pigments of the two kernel layers generally appeared a green color. These -color changes in the aleurone and pericarp layers of colored barley kernels strongly suggest the presence of anthocyanin pigments. Black pericarp pigments appeared unchanged under alkaline and acid conditions. Barley kernels of many varieties were extracted with alcohol and boiling 2N HCl and the pigment fractions of the extracts separated by paper partition chromatography. Two pigment fractions were obtained from extracts of "blue" seeded barley varieties and at least four from extracts of "purple" seeded varieties. The RF values of the pigment fractions obtained from extracts of "purple" seeded varieties were very similar to the RF values of the pigment fractions separating from extracts of red colored barley plant tissues. All these spots gave the characteristic red to blue color change of anthocyanins in acid and alkaline conditions. / Land and Food Systems, Faculty of / Graduate
29

Evaluation of Genomic Prediction and the Agronomic Performance of Facultative Barley

Reith, Francis Arthur 28 October 2024 (has links)
Cultivated barley typically exhibits either a winter growth habit or a spring growth habit. Some cultivars display a facultative growth habit, allowing them to be cultivated as either winter or spring crops. This study evaluated 1,128 elite barley cultivars and breeding lines under fall and spring sowing to determine which lines had a facultative growth habit and the underlying genetics thereof. In the fall of 2021 and subsequent spring of 2022, The first trial focused on identifying genetic factors associated with facultative habit. Results indicated that facultative lines were rare, with the majority exhibiting a winter growth habit. GENOME WIDE SCANS revealed no novel QTL associated with facultative habit, but significant QTLs on chromosome 4H were identified, correlating with the vernalization gene "VRN-H2." Several haplotypes found on chromosome 4H within appear significant and may contribute to differences in facultative habit. Only 28% of facultative lines could be accurately predicted based on genetic data, suggesting that facultative habit is a more complex trait than previously understood. Significant epistatic interactions between chromosome 4H and 4 other chromosomes were discovered. These findings indicate facultative habit is a much more quantitative trait than previously reported. The second trial involved growing the best-performing lines from the first trial under both fall and spring sowing conditions. Winter-sown barley consistently outperformed spring-sown barley in grain yield across all facultative lines. Despite strong performance under spring conditions, yield rankings were inconsistent across both sowing seasons, implying that agronomic performance cannot be reliably predicted across seasons. Notably, the Virginia Tech malt barley line 'Avalon' demonstrated facultative growth but exhibited poor agronomic quality under spring sowing. In contrast, lines such as 'VA22M-20DH1349' and 'VA22M-20DH1182' showed superior performance in both sowing regimes, indicating their potential for future breeding programs and agronomic trials for facultative barley in the American East. / Master of Science / Barley (Hordeum vulgare) is a dynamic crop with many important uses globally. Barley grain is nutritious and cheap to produce, and is important for livestock feed, direct human consumption, and for making malted products. In America, barley is primarily grown to produce malted products such as beer and liquor. Traditionally malt barley is grown in the Pacific Northwest and Upper Great Plains regions. However, due to the craft brewery revolution and rising economic and environmental concerns, there is significant interest in growing malt barley more local to where it will be malted, brewed, and consumed. Breeding malt barley lines that are suited for the eastern portions of America is important to meet the rising demands of consumers and brewers. Traditionally malt barley is of the spring growth habit (being planted in spring and harvested in late summer). Most barley cultivars for the American East are of the winter growth habit (being planted in fall and harvested in early summer). Some cultivars of barley may have the facultative growth habit, where they have the genetic capability to be cultivated as either the winter or spring crops. Here, 1128 elite cultivars and breeding lines adapted to the American East were screened for facultative growth habit. Two separate trials occurred. The first was focused on the genetic factors that permit lines to be facultative. Here, we observed that few lines are facultative, and most lines tend to exclusively be of the winter growth habit. Following a genome wide association study, no novel quantitative trait loci (QTL)related to facultative habit were discovered. QTLs heavily associated with facultative habit were observed on chromosome 4H. These QTL have previously been associated with the vernalization gene "VRN-H2". Additionally, using all genetic data available, only 28% of facultative lines could accurately be predicted. This result suggests facultative habit is a much more quantitative trait than previous studies have suggested. The second trial was an agronomic trial in which the best performing lines from the first trial were grown as both fall and spring sown crops. The same lines were cultivated across seasons, and their yields compared. The grain yield of winter sown barley outperformed spring sown barley for all facultative lines. Spring barley performed well agronomically, with some lines yielding more than 5500 Kg/Ha. Yield performance was not equal across seasons; meaning that top yielding lines under winter sowing were top yielding lines under spring sowing. Due to this it is unlikely that agronomic performance can be predicted across seasons, and we find that facultative performance will need to be evaluated in the field. We found the Virginia Tech malt barley line 'Avalon' to be facultative but holds poor agronomic quality under spring sowing. Several lines such as 'VA22M-20DH1349' and 'VA22M-20DH1182' exhibited superior performance across spring and winter sowing, and may be candidates for future breeding efforts or agronomic trials for spring and facultative barley in the American East.
30

Marker assisted backcrossing for gene introgression in barley (Hordeum vulgare L.) /

Jefferies, Stephen P. January 2000 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Plant Science, 2000. / Bibliography: leaves 183-211.

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