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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.
31

The estrogen-like activity and identification of certain isoflavones present in red clover

Hogg, Robert William January 1962 (has links)
A study was carried out to determine the relative estrogen-like activity attributed to the isoflavone compounds present in red clover plants (Trifolium pratense). The pure compounds were fed as additives to a non-estrogenic basal diet at total dosages ranging from zero to fifteen milligrams per mouse. The biological assay used for the determination of the estrogen-like activity was a slight modification of that outlined by Kitts et al. in 1959 (63). The isoflavone found to possess the greatest estrogen-like activity was Genisteim followed by Daidzein, Biochanin A and Formononetin. A non-isoflavone compound, Coumestrol, was found to possess a greater estrogen-like activity than any of the isoflavones considered. Mixtures of the pure isoflavones were bio assayed to observe any inhibitory or synergistic characteristics of one upon another. Biochanin A appeared to exert a slight inhibitory action and formononetin a synergistic character. An electrophoretic technique was developed which facilitated the detection of the isoflavones in plant extracts of monthly harvested red clover. An attempt was made to associate the biological activity of the red clover samples and the compounds which were observed in these same samples using electrophoresis / Land and Food Systems, Faculty of / Graduate
32

White clover seed production in British Columbia

Huxley, David Morton January 1978 (has links)
In the Creston valley in southeastern B.C., intermediate white clover is grown for seed and is a useful crop in farm field rotations. For several years seed yields have been declining, and despite good prices and markets, hectarage to white clover is declining. In 1976, work was initiated to determine some of the factors responsible for the decline in seed yield and hectarage. At the same time, an exploratory study of the genetic variation in the seed stocks of the valley was instituted in the hope that a Creston strain might be characterized or selected. In 1977, in the Creston valley, a series of replicated plots in six fields, representative of the edaphic, climatic and management regimes, were established to measure seed and forage yields and losses from multiple sources. At the University of B.C., four hundred individual plants representative of twenty sources, including some Creston sources, and encompassing substantial genetic diversity, were established from seed in replicated uniform nurseries. In an adjacent nursery one hundred and eighty Creston clones were established. Observation and measurement of a number of characters were taken on all plants several times during the growing season. Average clean seed yields on the Creston experimental plots ranged from 468-972 kgs. per hectare (418-868 lbs per acre). Farm yields of clean seed, by contrast, ranged from 262-491 kgs per hectare (240 to 450 lbs per acre). It was estimated that of the loss in seed threshed (dockage) , but not cleaned, 3-10% was insect damaged; loss attributable to farm harvesting procedures was estimated to reach 50%. Losses in the developing crop are difficult to assess quantitatively but appeared to be very serious. To offset these losses, in recent years, producers have been reducing the length of white clover ley and are now in most cases obtaining one seed crop only in the year after establishment; this practice, if carried on without counter selection, might result in a biennial habit. Three species of weevil appeared to be the most serious pests, viz. the clover root curculio (Sitona hispidula Fab.), and the clover seed weevil (Miccotrogus picirostris (F)) and the lesser clover leaf weevil (Hypera nigrirostris Fab.). The population peaks of the adults apparently occur at different times in the season. Currently only one aerial application of malathion is applied in June to control the clover seed weevil. Almost all roots examined bore signs of larval feeding, doubtless due to the clover root curculio; root nodules, abundant in spring, diminished rapidly as the season progressed. Measurements of nitrogen fixation, using the acetylene reduction technique and the Kjeldahl N-determination, were incomplete. Flower frequency and development, flower colour, leaf area, petiole length, leaf markings, plant height and weight, and prussic acid levels were some of the characters measured and observed on the individual plants, established in the U.B.C. nurseries from Creston and other sources. Not unexpectedly, the Creston stocks possessed a measure of distinction from most other stocks of intermediate white clover; nonetheless, there appeared to be ample variability in the Creston stocks within which to select strains to meet at least two needs of the region - viz. a) plants useful in the revegetation of ranges and of unstable soils, and b) plants well adapted to the arable long ley pastures of the humid and sub-humid areas. / Forestry, Faculty of / Graduate
33

Liguification studies with red clover.

Drapala, Walter J. January 1946 (has links)
No description available.
34

The biology of the clover mite, Bryobia praetiosa Koch, with preliminary investigations on its control.

Kelley, Roger Weston 01 January 1955 (has links) (PDF)
No description available.
35

Experimental induction of tropic responses in Trifolium Fragiferum L. stolons /

Hansen, Dale J. January 1969 (has links)
No description available.
36

Genetic analysis of chlorophyll deficiency in Melilotus alba x M. dentata hybrids with some observations on meitotic irregularities

Bringhurst, Royce S., January 1950 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1950. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 89-90).
37

The inheritance of chlorophyll deficiency and pollen sterility as barriers between Melilotus alba and M. dentata

Hinson, K. January 1954 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1954. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 79-80).
38

Genetic diversity and phylogenetic relationships of sweetclovers (Melilotus) germplasm resources

李麗瑩, Lee, Lai-ying, Rosita. January 1999 (has links)
published_or_final_version / Zoology / Master / Master of Philosophy
39

Inheritance and agronomic significance of adventitious root development in red clover (Trifolium pratense L.)

Montpetit, Jean-Marc January 1991 (has links)
Adventitious root growth from the crown of red clover constitutes a major portion of the root system in older stands. Two 2 yr old production fields and 3 yr old research plots were sampled in springs of 1988 and 1989 to determine the relationship between spring vigor and two root types of red clover. A higher average spring vigor rating was generally associated with the presence of well developed adventitious roots. / Five hundred and fifty-six red clover plants were dug in the fall of 1988 from a space planted (1 x 1 m centers) nursery established in the spring of the same year. Two divergent populations of 55 clones each were produced based on either a low or high score for adventitious root growth. The progeny of 32 single-crosses made within and between the two populations was evaluated for flowering habit and root types under spaced planting conditions during the 1989 growing season. / Six red clover cultivars were established in solid seedings to monitor adventitious root growth at three sampling dates.
40

Taxonomy and biology of Australasian solanaceae with additional studies of associated vegetation components /

Symon, David, January 1995 (has links) (PDF)
Thesis (D. Sc.)--University of Adelaide, Dept. of Botany, 1996? / Includes bibliographical references.

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