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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.
1

Some factors affecting the germination of seeds and plant responses to herbicides of three species of smartweed Polygonum pensylvanicum L., Polygonum persicaria L., and Polygonum lapathifolium L. /

Bayer, David E. January 1958 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1958. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 126-131).
2

Cytological and chemical parameters used to establish systematic relationships of two species of Polygonum Section Polygonum (Avicularia)

Brooks, George M. January 1971 (has links)
Plants collected in Wisconsin during September, 1970 were identified as P. ramosissimum and P. tenue according to the taxonomic characters established by Styles for European species of genus Polygonum and adapted for the North American species fo this genus by Mertens and Raven. The chromosome number for these two plants were determined to be 2n=60 for P. ramosissimum and 2n=30 or 32 for P. tenue. These counts were compared with chromosome numbers for Polygonum species for all of which the haploid count is either twenty or thirty. Chromatographic analysis of free amino acids and secondary substances further suggests that P. ramosissimum is properly assigned to section Polygonum while P. tenue should be placed in some other section of genus Polyyonum.
3

The Distribution and Economic Significance of the Genus Polygonum in Sacramento County of California

McCarthy, Helen Keech 01 January 1932 (has links) (PDF)
The genus Polygonum belongs to the family of plants, the Polygonaceae, which includes about forty genera and seven hundred and fifty species. About two hundred end seventy-five of these belong within Polygonum. Scientists have also found distinctly recognizable fossil Polygonums which date from prehistoric ages. Dr. F. H. Knowlton¹ of the U. S. National Museum has listed twelve species which have been found in fossil form. While studying collection of Colorado fossil plants in the Geological Tunes et Columbia College, Small discovered a remarkably distinct Polygonum belonging to the subgenus Persicaria.
4

A cytological study of Polygonum, section Polygonum (Avicularia) Specimens collected in Nova Scotia and New Brunswick

Moore, Donald N. 03 June 2011 (has links)
Ball State University LibrariesLibrary services and resources for knowledge buildingMasters ThesesThere is no abstract available for this thesis.
5

A cytotaxonomic and chromatographic study of genus Polygonum section Polygonum (Avicularia) specimens collected in New Brunswick, Prince Edward Island, and Nova Scotia

Jones, Daniel M. 03 June 2011 (has links)
The plant specimens investigated in this study were collected in Eastern Canada in August, 1969. Other plant specimens studied in this investigation were borrowed from the Gray herbarium of 1tarvard University. Information of three different types was obtained for the different plant specimens. Plants were examined morphologically; they were studied cytologically, to determine their chromosome numbers; and they were investigated chromatographically, to compare tie chromatographic patterns of their free amino acids and secondary substances.Plants identified as P, aviculare and P. arenastrur were found to be separate species based on differences in their morphology, chromosome numbers, and the chromatographic patterns of their secondary substances. Plants identified as P. Fowleri had a diploid chromosome number of 60. On the basis of the chromatographic patterns of their secondary substances. P. Fowleri and P. allocarpum appear to be separate species.Ball State UniversityMuncie, IN 47306
6

Implementation of a bioherbicide strategy for golf course environments

Gagné, Geneviève, January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Plant Science. Title from title page of PDF (viewed 2009/06/23). Includes bibliographical references.
7

Immunomodulatory effects of tryptanthrin on human bronchial epithelial cells

Yiu, Nai Sum 01 January 2005 (has links)
No description available.
8

Physiological and population ecology of two subalpine herbs on Mount St. Helens : contrasting strategies to a stressful environment /

Chapin, David Meyer. January 1986 (has links)
Thesis (Ph. D.)--University of Washington, 1986. / Vita. Bibliography: leaves [174]-187.
9

Pharmacognostical studies on Heshouwu (Polygoni Multiflori Radix): textual research, quality evaluation and processing chemistry investigation

Liang, Li 24 August 2018 (has links)
Heshouwu, derived from the tuberous root of Polygonum multiflorum Thunb., has been widely used in Traditional Chinese Medicine for centuries. It has a purgative effect when unprocessed, while used as a tonic after processing, and according to historical records, heshouwu should be steamed and sun-dried nine times to generate processed materials. Up until recently, three aspects of heshouwu have not been sufficiently studied. First, it is necessary to understand the history of heshouwu, including the emergence in the literature, the descriptions of its appearance, its effects and controversies, as well as the evolution of heshouwu's processing. As historical texts open a window to the past and clarify the issues of important clinical concern in the modern world, historical bencao (materia medica) literature research should be conducted. Second, in commercial herbal markets, heshouwu is divided into different grades based on morphological features of size and weight. A heavier weight and larger size command a higher price, and both sellers and buyers accept this grading. However, two questions arise: Does the existing grading system accurately represent the quality of the herb? If not, is there another system, or are there other morphological criteria, that could be used to reliably represent quality? Lastly, while heshouwu has been processed for hundreds of years, including the present, the chemistry of that processing has not been well studied. To address these issues, this study is divided into four parts. First, a systematic review of the text and illustrations in historical bencao literature is conducted. The bencao literature study illustrates the origin, botanical characteristics, actions and processing of heshouwu, as well as the origin and historical evolution of baishouwu ("white heshouwu"). To assess the inherent quality of various grades and to explore whether the existing grading system of heshouwu accurately represent quality, we firstly analyze the chemical profiles in three different commercial grades of heshouwu raw materials, using UPLC-QTOF-MS/MS and UPLC-QqQ-MS/MS. The results reveal that production regions and specifications both influence the chemical constituents of heshouwu, but the influence of production regions is even more evident. Differences in the constituents among production regions are relatively large, while there are no significant differences among the existing commercials grades. As the relationship between bioactive components and morphological features can be found by analyzing the distribution patterns of chemical components in different tissues, in order to find other reliable morphological indicators of quality furtherly, a method combining laser microdissection (LMD), UPLC-QTOF-MS/MS and UPLC-QqQ-MS/MS is applied in the third part of this study. The results indicate that, heshouwu with broader cork and phloem, as seen in a transverse section, are typically of better quality as these parts are where the bioactive components accumulate. In the fourth part of this study, targeted and untargeted metabolomics analyses using UPLC-QTOF-MS/MS and UPLC-QqQ-MS/MS are integrated to investigate the processing chemistry of heshouwu. The results demonstrate that processing by nine cycles of steaming and drying can qualitatively and quantitatively alters the chemical profile of heshouwu, which suggests that the nine cycles might be necessary for the preparation of processed heshouwu. The historical bencao literature research, chemical basis for quality evaluation, as well as processing chemistry investigation of heshouwu have been conducted in depth in this study. The results will be helpful in providing scientific basis of heshouwu's application.
10

Effect of fertilizer on lead (Pb) accumulation ability of Polygonum hydropiper L.

Chu, Thi Thu Ha, Nguyen, Phuong Hanh, Nguyen, Thi Hien, Ha, Thi Van Anh, Nguyen, The Cuong, Nguyen, Thi Thu Anh, Nguyen, Duc Anh, Dang, Van An, Vu, Van Tu 16 January 2019 (has links)
Polygonum hydropiper L. was cultivated on alluvial soil (Pb = 2.6 mg/kg, dry weight) and Pb contaminated soil (Pb = 1,380 mg/kg dry weight) without and with amendment of 2 g organic fertilizer/kg soil and 2.5; 5.0; 10.0 g NPK fertilizer/1kg soil. After 45 days of cultivation, the growth in height and biomass of P. hydropiper in Pb contaminated soil without amendment of fertilizer was lower than that in alluvial soil, but the Pb content in the above-ground part of the P. hydropiper was higher. In the formula 4, on Pb contaminated soil (Pb = 1,380 mg/kg dry weight), when amending 2 g of microbiological organic fertilizer + 5 g NPK fertilizer per 1 kg of soil (with the total nutrients amended were: N = 0.25, P2O5= 0.52, K2O = 0.15, and organic matter = 0.21 g/kg soil), growth of P. hydropiper was optimal (its height and biomass were up to 244.0% and 284.9% in comparison to that of before experiment) and their Pb extraction potential was promoted to the highest level among the formulae used. The average level of Pb accumulated in the above-ground part of P. hydropiper cultivated at formula 4 was 1,098.3 mg/kg dry weight (DW) after 45 days of cultivation that was 1.6 time higher than the one of formula 2 without fertilizer amendment (687.8 mg/kg DW). The potential of Pb extracted and stored in the above-ground part of P. hydropiper cultivated at formula 4 after 45 days was 479.2 g/ha that was 2.85 time higher than the one of formula 2 without fertilizer amendment (168.02 g/ha). / Nghể răm Polygonum hydropiper L. được trồng theo 5 công thức trên đất phù sa không ô nhiễm chì (Pb = 2,6 mg/kg khô) và đất ô nhiễm chì (Pb = 1380 mg/kg khô)không bón phân và có bón phân với các liều lượng 2 g phân hữu cơ vi sinh/1 kg đất và 2,5; 5,0; 10,0 g phân NPK /1 kg đất. Sau 45 ngày thí nghiệm trồng cây, tăng trưởng về chiều cao và sinh khối của cây trên đất ô nhiễm Pb không bón phân thấp hơn trên đất phù sa, nhưng hàm lượng Pb trong phần trên mặt đất của cây cao hơn. Ở công thức (CT) 4, trên đất ô nhiễm chì (Pb = 1380 mg/kg khô) khi bón phân với liều lượng 2 g hữu cơ + 5 g NPK/1 kg đất (với tổng hàm lượng dinh dưỡng được bón là: N = 0,25, P2O5= 0,52, K2O = 0,15, và chất hữu cơ = 0,21 g/kg đất) thì tăng trưởng của câynghể răm đạt tối ưu (chiều cao và khối lượng đạt 244,0 % và 284, 9% so với trước thí nghiệm) và tiềm năng hút thu Pb của chúng cũng được thúc đẩy cao nhất trong số các công thức được sử dụng. Lượng Pb trung bình tích lũy trong phần trên mặt đất của nghể răm ở CT 4 đạt 1.098,3 mg/kg khô sau 45 ngày trồng, cao gấp 1,6 lần so với cây ở công thức 2 không bón phân (687,8 mg/kg khô). Khả năng loại bỏ Pb từ đất ô nhiễm của nghể răm khi được bón phân ở CT4 đạt 479,2 g/ha sau 45 ngày trồng, cao gấp 2,85 lần so với cây ở CT 2 không bón phân (168,02 g/ha).

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