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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.
271

Selective isolation and characterisation of streptomycetes associated with the rhizosphere of the tropical legume, Paraserianthes falcataria (L) Nielsen

Sembiring, Langkah January 2000 (has links)
No description available.
272

Water use and fibrous root growth of sugar beet

Brown, K. January 1986 (has links)
No description available.
273

Aspects of signalling and development during the Rhizobium-legume symbiosis

Walker, Simon A. January 2000 (has links)
No description available.
274

Bolting and flowering mechanisms in sugar beet, Beta vulgaris, ssp vulgaris (L)

Debenham, Gunnel Birgitta January 2000 (has links)
No description available.
275

Capture of soil water by crop root systems

Hector, D. J. January 1987 (has links)
No description available.
276

Silicon amelioration of aluminium toxicity in wheat

Cocker, Kay M. January 1997 (has links)
No description available.
277

The hidden life of plants : fine root dynamics in northern ecosystems

Blume-Werry, Gesche January 2016 (has links)
Fine roots constitute a large part of the primary production in northern (arctic and boreal) ecosystems, and are key players in ecosystem fluxes of water, nutrients and carbon. Data on root dynamics are generally rare, especially so in northern ecosystems. However, those ecosystems undergo the most rapid climatic changes on the planet and a profound understanding of form, function and dynamics of roots in such ecosystems is essential. This thesis aimed to advance our knowledge about fine root dynamics in northern ecosystems, with a focus on fine root phenology in natural plant communities and how climate change might alter it. Factors considered included thickness and duration of snow cover, thawing of permafrost, as well as natural gradients in temperature. Experiments and observational studies were located around Abisko (68°21' N, 18°45' E), and in a boreal forest close to Vindeln (64°14'N, 19°46'E), northern Sweden. Root responses included root growth, total root length, and root litter input, always involving seasonal changes therein, measured with minirhizotrons. Root biomass was also determined with destructive soil sampling. Additionally, aboveground response parameters, such as phenology and growth, and environmental parameters, such as air and soil temperatures, were assessed. This thesis reveals that aboveground patterns or responses cannot be directly translated belowground and urges a decoupling of above- and belowground phenology in terrestrial biosphere models. Specifically, root growth occurred outside of the photosynthetically active period of tundra plants. Moreover, patterns observed in arctic and boreal ecosystems diverged from those of temperate systems, and models including root parameters may thus need specific parameterization for northern ecosystems. In addition, this thesis showed that plant communities differ in root properties, and that changes in plant community compositions can thus induce changes in root dynamics and functioning. This underlines the importance of a thorough understanding of root dynamics in different plant community types in order to understand and predict how changes in plant communities in response to climate change will translate into root dynamics. Overall, this thesis describes root dynamics in response to a variety of factors, because a deeper knowledge about root dynamics will enable a better understanding of ecosystem processes, as well as improve model prediction of how northern ecosystems will respond to climate change.
278

The function of the transcription factor HLH-6 in the esophageal gland cells of root knot nematodes (meloidogyne)

Loewen, Royden A. 27 September 2016 (has links)
Root-knot nematodes (RKN) are plant parasites, and a major agricultural pest. RKN are adept at invading and feeding on plant tissue with secretions they release from their gland cells. This thesis compares glandular development in Meloidogyne to the model nematode, Caenorhabditis elegans. Pharyngeal and gland important transcription factors, PHA-4 and HLH-6, respectively, were examined for their role in regulation of parasite-specific genes. Homologues of these genes were identified and sequenced from M. incognita. Phylogenetic analyses revealed a new PPN-specific gene, hlh-6-like. Bioinformatic comparisons of the homologues revealed conservation of the DNA-binding motifs of Ce-HLH-6 and Mi-HLH-6 proteins, as well as conservation of their promoter regions. While HLH-6 antibodies proved inconclusive, expression assays revealed expectant levels of PHA-4 and HLH-6 in Meloidogyne as compared to C. elegans. In identifying genes essential for parasitism we are providing new targets for knockdown during RKN infection. / October 2016
279

The hidden life of plants : fine root dynamics in northern ecosystems

Blume-Werry, Gesche January 2016 (has links)
Fine roots constitute a large part of the primary production in northern (arctic and boreal) ecosystems, and are key players in ecosystem fluxes of water, nutrients and carbon. Data on root dynamics are generally rare, especially so in northern ecosystems. However, those ecosystems undergo the most rapid climatic changes on the planet and a profound understanding of form, function and dynamics of roots in such ecosystems is essential. This thesis aimed to advance our knowledge about fine root dynamics in northern ecosystems, with a focus on fine root phenology in natural plant communities and how climate change might alter it. Factors considered included thickness and duration of snow cover, thawing of permafrost, as well as natural gradients in temperature. Experiments and observational studies were located around Abisko (68°21' N, 18°45' E), and in a boreal forest close to Vindeln (64°14'N, 19°46'E), northern Sweden. Root responses included root growth, total root length, and root litter input, always involving seasonal changes therein, measured with minirhizotrons. Root biomass was also determined with destructive soil sampling. Additionally, aboveground response parameters, such as phenology and growth, and environmental parameters, such as air and soil temperatures, were assessed. This thesis reveals that aboveground patterns or responses cannot be directly translated belowground and urges a decoupling of above- and belowground phenology in terrestrial biosphere models. Specifically, root growth occurred outside of the photosynthetically active period of tundra plants. Moreover, patterns observed in arctic and boreal ecosystems diverged from those of temperate systems, and models including root parameters may thus need specific parameterization for northern ecosystems. In addition, this thesis showed that plant communities differ in root properties, and that changes in plant community compositions can thus induce changes in root dynamics and functioning. This underlines the importance of a thorough understanding of root dynamics in different plant community types in order to understand and predict how changes in plant communities in response to climate change will translate into root dynamics. Overall, this thesis describes root dynamics in response to a variety of factors, because a deeper knowledge about root dynamics will enable a better understanding of ecosystem processes, as well as improve model prediction of how northern ecosystems will respond to climate change.
280

Species-specific fine root biomass, morphology and dynamics of six co-occurring deciduous tree species in the Hainich National Park and a conifer tree species at the alpine treeline

Kubisch, Petra 09 September 2015 (has links)
No description available.

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