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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.
51

Samplanteringar med härdiga barrväxter i fokus : -Designförslag i tre tänkta miljöer

Laggren, Malin January 2015 (has links)
Denna uppsats presenterar tre designförslag på samplanteringar med barrväxter i fokus. Designförslagen är gjorda till tre fiktiva platser med olika ståndort i växtzon 5, en liten entréplantering i västerläge med kalkhaltig jord, en mellanstor plantering i söderslänt med sandblandad jord och en parkplantering med fuktig jord med ett lågt pH-värde. Platserna är valda med tanken att läsarna ska kunna inspireras att använda barrväxter i olika typer av planteringar och trädgårdar. Till grund för växtvalen har gjorts en litteraturstudie inom området barrväxter, med fokus på barrväxters ståndort och hur de fungerar i samplanteringar med perenner och lignoser. Bakom designförslagen ligger även en idé om att hitta lite nya sätt att använda barrväxter, detta för att inte göra upprepningar av de skötselfria planteringarna med barrväxter som blev så oerhört populära på 70-talet och som delvis givit barrväxter ett dåligt rykte. Designförslagen presenteras i utförliga illustrationer och genom en processbeskrivning för att belysa designprocessens vägar och val, från början till slut.
52

Attempts to cause differentiation of callus tissue of Abies concolor by tissue culture technique

Schnurbusch, Donald Joseph January 1972 (has links)
Abies concolor (white fir) is one of the many conifers often planted as an ornamental tree. Like so many other conifers, Abies is difficult to vegetatively propagate. Recent successes in using the techniques of tissue culture as a means of vegetatively propagating plants prompted the present study of applying these techniques to Abies.A review of the literature indicated that no conifer had ever been grown into plantlets by using the techniques of tissue culture. Only a very few reports exist for cellular differentiation although nearly thirty species of conifers have been grown in-vitro as callus.The review of literature also indicated that a variety of growth regulators, supplements and conditions of growth were utilized in promoting differentiation and the development of plants from callus. Since no consistent patterns emerge as guidelines for achieving differentiation, a proposal was made to test the effects of several growth regulators on callus tissue of Abies in hopes of causing differentiation and organogenesis.Terminal stem sections from the lower branches of a mature tree of Abies concolor were removed, sterilized and and placed on experimental solid media containing mineral salts, growth regulators and organic supplements. Growth of a callus occurred as a cream-colored friable mass on several of the media. When examined, however, the growth was found to consist of only parenchymatous cells. When transferred to a medium (G7) containing coconut milk, casein hydrolysate and 2 mg/l kinetin, compact, hemispherical nodules developed over a period of six weeks.A number of these nodules were fixed, embedded,'sectioned and stained with safranin and fast green. These were examined with a microscope and comparative photographs between this type of growth and the friable callus were made.Sections of the nodules showed a more compact arrangement of cells and an incomplete ring of growth consisting of cells arranged in radial files as if produced by a cambium. The center of the incomplete ring contained parenchymatous cells primarily, but scattered tracheid-like cells with bordered pits were also noted. Photographs of the well organized incomplete ring of growth and the tracheid-like cells were made.It can be concluded that differentiation of Abies concolor callus did occur on the G7 medium and that this represents a positive step toward organogenesis using the techniques of tissue culture.
53

MADS-box gene phylogeny and the evolution of plant form : characterisation of a family of regulators of reproductive development from the conifer Norway spruce, Picea abies /

Carlsbecker, Annelie January 2002 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2002. / Härtill 4 uppsatser.
54

Incidence of root and butt rot in consecutive rotations, with emphasis on Heterobasidion annosum in Norway spruce /

Rönnberg, Jonas, January 1900 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
55

Douglas-fir, grand fir and plant community regeneration in three silvicultural systems in western Oregon /

Ketchum, J. Scott. January 1995 (has links)
Thesis (M.S.)--Oregon State University, 1995. / Typescript (photocopy). Includes bibliographical references (leaves 79-82). Also available on the World Wide Web.
56

Adaptive evolution and demographic history of Norway spruce (Picea abies) /

Källman, Thomas, January 2009 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2009. / Härtill 5 uppsatser.
57

Testování účinnosti chuťových repelentů pro ochranu zakládaných výsadeb lesních dřevin před okusem zvěří / Evaluation of taste repellents for protection of tree planting stock from deer browsing

Triner, Libor January 2016 (has links)
The main goal of this thesis is to assess the efficacy of two repellent products with active ingredients denatonium benzoate and capsaicin to protect the newly established forest tree planting prior to browsing damage by wild game. Repellents were tested on two different experimental plots planted with silver fir (Abies alba). Application of repellents held in three terms and total three times were the damages, which were included in the framework of the six-rating scale, has been detected. The effectiveness of these repellents has been demonstrated already during the second term damage assessments caused by game. During the more than 14-month experiment was damaged almost 2.5 times fewer seedlings treated with repellents based on denatonium benzoate and capsaicin than untreated seedlings, serving as a control. The most common form of damage to the tree was bitten off terminal bud with little scope of additional damage. Damage to seedlings by game differed significantly even within the investigated areas. Use of repellents did not affect the physiological death of seedlings. It was justify the conclusion that most of the damages were caused by roe deer (Capreolus capreolus). Based on several scientific papers on the efficacy of repellent products based on capsaicin and denatonium benzoate was concluded that the main active ingredient in tested repellents is capsaicin.
58

Improving the methods for cryopreservation of endangered conifers

Gaiduschová, Daniela January 2016 (has links)
Preservation of plant genetic material is essential for any biological field. Compared to serial in vitro sub-culturing, cryopreservation often represents optimal long-term conservation technique. The crucial factors influencing successful cryopreservation include 1) proper pre-treatment, 2) cryoprotectants, 3) adequate freezing pace and 4) cold-hardening. Finding the appropriate method for cryopreservation of each species is the ultimate goal of research in this field. This work is focused on finding the optimal protocol for cryopreservation of embryogenic cell masses of coniferous species bog pine (Pinus uncinata subsp. uliginosa) and optimizing the existing one for European silver fir (Abies alba), both endangered in the Czech countryside. Cryopreservation design compares effectivity of different pre-treatments and cryoprotectants, determines the role of cold-acclimation step and evaluates resistance of selected conifer cell lines to freezing and desiccation. Post-thaw recovery of Bog pine cell line BE4 was better than cell line BR1, where no living cells were visible using FDA/PI staining. Proliferation rate was higher for European silver fir than for bog pine, especially for cell line II-2-10. Cryoprotective mixture with DMSO (PGD I) proved to be more effective than the mixture with glycerol (PGG) in cryopreservation of European silver fir. PGD I also proved to be optimal cryoprotective mixture for bog pine. In both cases, 0.4M sucrose was used as a pre-treatment and cold-hardening was included.
59

Mapování chromozomů smrku (Picea abies (L.) Karst.) pomocí chromozomově specifických sond

Überall, Ivo January 2004 (has links)
No description available.
60

Vliv klimatických stresorů na kmenoviny smrku ztepilého v oblasti severovýchodní Moravy

Stanovský, Jiří January 2003 (has links)
Angl. resumé

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