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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.
41

Potencial de uso de gramíneas como substrato pasteurizado no cultivo do cogumelo Pleurotus ostreatus (Jacq.) P. Kumm. /

Vieira, Fabrício Rocha, 1982- January 2012 (has links)
Orientador: Marli Teixeira de Almeida Minhoni / Banca: Ceci Sales da Gama Campos / Banca: Meire Cristina Nogueira de Andrade / Resumo: O cultivo de cogumelos comestíveis e medicinais pode ser realizado em diversos substratos liginocelulósico em sistema axênico e pasteurizado. O gênero Pleurotus é conhecido principalmente pela espécie Pleurotus ostreatus conhecido popularmente como cogumelo ostra, shimeji ou hiratake. Neste trabalho, investigou-se a variabilidade genética de quatro linhagens de Pleurotus ostreatus pela técnica RAPD, o crescimento micelial em meio de cultura sólido, parâmetros da compostagem (umidade do substrato, dinâmica da relação C/N, pH, perda de massa fresca, celulose, hemicelulose, lignina, proteína total e fibra total), produtividade, eficiência biológica e qualidade nutricional dos basidiomas (proteína total, fibra total e extrato etéreo) cultivados nos diferentes substratos em duas relações C/N. As linhagens de P. ostreatus foram coletadas de produtores do Estado de São Paulo e os materiais utilizados para a elaboração dos substratos de cultivo foram: capim braquiária, capim tobiatã, capim brizantha, palha de cana-de-açúcar, palha de trigo, bagaço de cana-de-açúcar e farelo de trigo. No primeiro experimento foi avaliado a variabilidade genética pela técnica RAPD das quatro linhagens de P. ostreatus coletadas de produtores do Estado de São Paulo. Assim foram divididos em dois grupos distintos, o primeiro grupo com as linhagens POS 09/100, POS 09/101 e POS 09/102 e o segundo grupo com a linhagem POS 98/38. Sendo que dentro do primeiro grupo as linhagens POS 09/100 e POS 09/101 apresentaram similaridade de 93%, ainda... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The cultivation of edible and medicinal mushrooms can be accomplished on various lignocellulosic substrates in system axenic or pasteurized. The Pleurotus genus is mainly known by the species as Pleurotus ostreatus popularly known oyster mushroom, shimeji or hiratake. In this study, we investigated the genetic variability of four strains of Pleurotus ostreatus by RAPD, the mycelial growth on solid medium, composting parameters (substrate moisture, dynamics of C/N ratio, pH, weight loss, cellulose, hemicellulose, lignin, total protein and total fiber), productivity and nutritional quality of mushrooms (total protein, total fiber and lipids) grown on different substrates in two C/N ratio. The strains of P. ostreatus were collected from producers of São Paulo State and the materials used for the preparation of substrates were: brachiaria grass, tobiatã grass, brizantha grass, sugar cane straw, wheat straw, sugar cane bagasse and wheat bran. In the first experiment evaluated the genetic variability by RAPD of four strains of P. ostreatus collected from producers of São Paulo State. So were divided into two distinct groups: the first group with the strains POS 09/100, POS 09/101 and 09/102 and the second group with the strain POS 98/38. Since the first group within the strains POS 09/100 and POS 09/101 showed similarly of 69% over the two aforementioned strains. In second group the strain POS 98/38 showed similarity of 36% compared to with the first group. In the second experiment evaluated the mycelial growth in culture media based on the substrate collected at the end of Phase II composting. Was used the punctuation in defined time periods (24 hours) to determine colony growth and non-parametric method of Stundent- Newman-Kills for transforming the values in growth curves higher growth rates were obtained on... (Complete abstract click electronic access below) / Mestre
42

The effect of activated carbon on the organic and elemental composition of plant tissue culture medium

Van Winkle, Stephen C. 05 1900 (has links)
No description available.
43

Some aspects of litterfall and decomposition : fuel accumulation in two plant stands in Taipo Kau forest reserve, New Territories, Hong Kong /

Mak, Hon-tak. January 1978 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1980.
44

The effect of charcoal on tissue morphogenesis in vitro.

Pan, Manjing. 17 December 2013 (has links)
The effect of activated charcoal, autoclaving and culture media on sucrose hydrolysis in tissue culture media was investigated. Activated charcoal acidified an aqueous sucrose (5%) solution and culture media by about 1 to 2 units after autoclaving . Sucrose hydrolysis in tissue culture media and/or aqueous sucrose (5%) solutions containing activated charcoal (buffered to pH 5.8) was dependent on both the hydrogen ion concentration (pH) and autoclaving. After autoclaving, 70%, 56% and 53% sucrose hydrolysis were respectively recorded in a 5.0% sucrose solution, Murashige and Skoog (MS) and Gamborg B5 (B5) liquid media in the presence of 1.0% activated charcoal, added before autoclaving . In the absence of activated charcoal, autoclaving resulted in about 20% of the sucrose being hydrolysed The adsorption of 2, 4-dichlorophenoxyacetic acid (2,4-D) by activated charcoal from methanol and aqueous solutions was determinated using HPLC. The amount of the added 2,4-D decreased in both methanol and aqueous solutions in the presence of activated charcoal, compared with those in the absence of activated charcoal. In methanol and aqueous solutions, activated charcoal used at the level of 0.1% significantly reduced 2,4-D. About 68.4% and 60.9% respectively of the added 2,4-D was adsorbed by activated charcoal (1.0%) from these solutions. The changes of inorganic elements in MS-salt solutions, in the presence of activated charcoal, were analysed by SEM-EDX. The concentrations of magnesium (Mg), calcium (Ca), iron (Fe) and zinc (Zn) deceased in the presence of activated charcoal, while the concentrations of potassium (K), copper (Cu), manganese (Mn), phosphorus (P), and sulphur (S) increased in the MS salt solution in the presence of activated charcoal compared with no activated charcoal in the medium. This suggests that activated charcoal adsorbed calcium, magnesium, iron and zinc and released copper, manganese, phosphorus and sulphur. Rooting occurred when 7-day-old seedling hypocotyls of Daucus carota L. Cape Market were placed on MS medium supplemented with 2,4-D, and IAN/NAA in the presence of activated charcoal. Hypocotyls did not produce roots on the 2,4-D containing media in the absence of activated charcoal. The roots were produced polarly on the NAA/IAA-containing media in the presence of activated charcoal. No-polarity of root formation was observed on media supplemented with NAA/IAA without activated charcoal. Different responses of hypocotyls to a series of 2,4-D concentrations (0.5, 1.0, 3.05.0, 8.0, and 10.0 mg l ¯¹) were observed on media supplemented with 0.02, 0.1 and 0.5% activated charcoal. In the NAA/IAA containing media in the presence of activated charcoal, root number per hypocotyl decreased. Root number perhypocotyl, on the media supplemented with NAA and IAA, increased when hypocotyls were pre-cultured on MS medium supplemented with 2,4-D (1.0 mg l ¯¹) for 2-3 days. When hypocotyls were pre-cultured on a 2,4-D containing MS medium for 5 days, embryos emerged from the hypocotyls directly on the medium supplemented with 2,4-D in the presence of activated charcoal. Addition of activated charcoal to MS medium supplemented with 2,4-D resulted in somatic embryogenesis of Daucus carota. Somatic embryos were not formed on the medium in the absence of activated charcoal. In suspension culture, the incorporation of 0.01 to 1.0% concentrations of activated charcoal to the MS medium, irrespective of 2,4-D, increased the number of somatic embryos produced. The maximum number of somatic embryos were produced with 1.0% activated charcoal. Further development of embryos of Daucus carota occurred on the media in the presence of activated charcoal, and the embryos subsequently regenerated normal plantlets. Abnormal somatic embryos followed the addition of 3.0% activated charcoal to the medium. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 2000.
45

Recirculating hydroponic systems : evaluating cuttings yield and rooting ability of cold tolerant eucalyptus hybrids.

Wallis, Jacqueline Tanya. January 2004 (has links)
In South Africa, clonal forestry of Eucalyptus and its hybrids has been implemented to increase the productivity on existing forestry lands and marginal sites and to facilitate the production of desired fibre types for timber processing operations. The cold-tolerant Eucalyptus grandis x E. nitens hybrids have produced consistently high yields, and are propagated clonally with limited success via a macro-cutting system currently in use for other hybrid species. The heart of vegetative propagation operations is the clonal hedge and its management, and nutrition in particular, is an important element of any vegetative propagation programme. However, achieving and sustaining an optimum nutritional balance in macrohedges is difficult in practice and, in order to accurately predetermine the optimum plant nutrition required all year round and to ensure optimal levels of rooting, a more controllable nutrient environment is essential. Hydroponics may facilitate this control of nutrition. At the same time it may be possible to manipulate the system to determine accurately what levels of each nutrient may contribute to the highest rooting and more importantly allow forest nursery managers to maintain those levels in a practical manner. The main aims of the present work were to obtain and compare cuttings and rooting yields from hydro-ramets in different hydroponic substrates and systems and to investigate the possible roles of essential nutrients on those parameters. Modified Nutrient Film Technique (NFT), ebb-and-flow and aeroponic tables were used in this study. The former consisted of eight individual gutters, allowing for eight different substrates to be tested simultaneously. One gutter was set up as an unmodified NFT table and the other seven gutters had gravel, Leca, peat, perlite, perlite: vermiculite mix, Rockwool® and sand as substrates; all were supplied with the same nutrient solution. Three commercial clones were used throughout these trials: GN107, GN156 and NHOO. Rooting results and data from plant elemental analyses indicated that certain elements (Ca, Cu, Zn, Mn and B) appeared to play a more important role in rooting than others (N, P, K, Mg, Na and Fe). It was also found that when comparing the hydroponic systems, the substrate and / or method of irrigation affected the availability and uptake of different nutrients, which in turn affected the rooting of coppice collected from those ramets. The rooting performance of coppice from the eight different substrates tested in the NFT system was compared. Within each of the four harvests undertaken, both clone and substrate had a significant effect on the rooting performance. However, when the four harvests were compared, only harvest number/time had a significant effect on the rooting performance of the cuttings derived from the hydro-hedges . For both the ebb-and-flow and aeroponics systems (where there was no substrate), only the clone had a significant effect on the rooting performance. In addition to this, the plants from the ebb-and-flow system produced the highest number of cuttings to be placed overall (7.9 cuttings per mother plant per harvest) while those from the gravel substrate had the highest rooting percentage overall (26.9 %). When combining these two factors into a success rate, the perlite substrate rated highest (1.7 rooted cuttings per mother plant per harvest). From a cost efficiency perspective, perlite was the most cost effective substrate, as it required the least initial capital outlay to produce one million rooted clones per year from a hydroponics system (R6 533 655). The plants in the perlite substrate also produced the highest number (6 700) of rooted cuttings per year from 1 000 mother plants with a low cost per plant (R2.33 per rooted plant). / Thesis (M.Sc.)-University of KwaZulu- Natal, Durban, 2004.
46

Various weed control techniques in container nursery production

Cochran, Diana Renae, January 2007 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (ℓ. 69-74)
47

Extensive vegetated roofs in Sweden : establishment, development and environmental quality /

Emilsson, Tobias, January 2006 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
48

Evaluation of spent tea grinds as an alternative horticultural substrate component

Wells, Daniel Evans, Sibley, Jeffrey Lynn, January 2008 (has links)
Thesis--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references.
49

Evaluation of clean chip residual as an alternative substrate for container-grown plants

Boyer, Cheryl ReNee', Gilliam, Charles Homer, Fain, Glenn Bradley, January 2008 (has links) (PDF)
Thesis (Ph. D.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 173-188).
50

Some aspects of litterfall and decomposition fuel accumulation in two plant stands in Taipo Kau forest reserve, New Territories, Hong Kong /

Mak, Hon-tak. January 1978 (has links)
Thesis (M.Phil.)--University of Hong Kong, 1980. / Also available in print.

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