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Showing 1 to 20 of 24 for “"nitrogen-fixing bacteria"”.
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Ecology of nitrogen-fixing bacteria associated with Miscanthus
… for bioenergy crops, such as Miscanthus. Nitrogen is the most expensive and most limiting nutrient in agricultural systems, so it is necessary to develop strategies to reduce anthropogenic inputs of nitrogen fertilizer. Diazotrophs associated with non-leguminous grasses have great …
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Ecological genomics of mutualism decline in nitrogen-fixing bacteria
… the forces that maintain cooperation in nature. Bacterial mutualists in particular might evolve more quickly than other organisms in response to environmental changes, thanks to short generation times and horizontal gene transfer, providing an ideal system in which to address questions of …
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Diversity of Free-living Nitrogen Fixing Bacteria in the Badlands of South Dakota
<p>Biological Nitrogen Fixation is carried out by a highly diverse group of members of the domains Bacteria and Archaea which express a nitrogenase enzyme complex and are termed diazotrophs. The best known diazotrophs form symbiotic associations with plants, but free-living nitrogen fixing bacteria …
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Detection and Capture of Nitrogen Fixing Bacteria From Soil and Roots Using Plant Specific Lectins
… reduction or application of harmful synthetic nitrogen fertilizers. This thesis aims to use plant root proteins, or lectins, to more rapidly recover viable diazotrophs that are likely to associate with crops. In this study, lectins, are used to recover bacteria from bulk soil by taking …
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Evaluation of Nitrogenase Genes as Markers in Soil Microbial Community Studies
… to overcome some of the constraints to analyzing nitrogen-fixing bacteria in the environment. Two distinct plant-microbe systems were used to develop these tools, and to evaluate their utility and flexibility. The first system focused on nitrogen-fixing bacteria in the rhizosphere of salt-meadow …
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Pseudomonas spp. Isolated from Soybean Nodules Promote Soybean Growth and Nitrogen Fixation
Nitrogen-fixing bacteria in soybean nodules convert atmospheric nitrogen to plant-available forms in exchange for carbon from the plant, but other non-nitrogen-fixing bacteria also reside in nodules, and their role in the nodule is not well understood. This study was conducted to determine the …
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Legume-rhizobia interactions in a complex microbiome
Biological nitrogen fixation is important for agriculture, carbon sequestration, and ecosystem restoration. This is primarily conducted by rhizobia (nitrogen fixing bacteria) in association with legume plants. Most research in improving rhizobial strains involves single strain experiments. However, …
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Legume-rhizobia interactions in a complex microbiome
Biological nitrogen fixation is important for agriculture, carbon sequestration, and ecosystem restoration. This is primarily conducted by rhizobia (nitrogen fixing bacteria) in association with legume plants. Most research in improving rhizobial strains involves single strain experiments. However, …
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Pseudomonas spp. Isolated from the Soybean Nodule Interior Promote Soybean Growth upon Field Amendment
… reside in soybean nodules; however, other non-nitrogen fixing bacteria are a part of the interior nodule microbiome. Results from a previous greenhouse study show that a novel species of Pseudomonas associates with soybean nodules as a plant-growth promoting rhizobacteria (PGPR). This study …
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Gene Expression Profiling of the nip Mutant in Medicago truncatula
The study of root nodule symbiosis between nitrogen-fixing bacteria and leguminous plant species is important because of the ability to supplement fixed nitrogen fertilizers and increase plant growth in poor soils. Our group has isolated a mutant called nip in the model legume Medicago truncatula …
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The study of rehabilation of hydrocarbon contaminated soil using bio-remedial microbes
… Counts, Nitrofyers, Nitrosojyers and Free-living nitrogen fixing bacteria (Chan^L aL, 1993). The four groups of microbial counts were used as a biological parameter, and there was a correlation between each other as well as with the residua] hydrocarbon concentration, indicating the importance of …
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Characterisation and expression of Receptor-like Cytoplasmic Kinases in Medicago truncatula during Rhizobial and Arbuscular Mycorrhizal symbioses
… the ability to form a mutualistic symbiosis with nitrogen-fixing bacteria known as rhizobia. Studies using mutant Medicago truncatula and Lotus japonicus have identified many genes that are necessary for this mutualism. Some of these genes have also been shown to be necessary for symbiosis with …
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Exploring the Potential of Algae-Bacteria Communities For Biotechnology
… organisms ranging from prokaryotic cyanobacteria to eukaryotic algae spread across many phyla. Traditional algal biotechnology approaches have focused on growing algae in monoculture, in contrast to nature, where algae live in association with many other organisms. One association of …
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Improved Environmental Characterization to Support Natural Resource Decision Making: (1) Distributed Soil Characterization, and (2) Treatment of Legacy Nutrients
… (1) accurate soil mapping and (2) treatment of nitrogen to affect water quality change.The current method of soil mapping, SSURGO (USDA‐NRCS Soil survey), is often erroneous and misleading. Two studies in this dissertation are conducted to evaluate the potential that different resolution digital …
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Diversity and distribution of Tylosema esculentum (Marama bean) endophytic bacteria communities in Omitara, Harnas and Otjinene, eastern Namibia
… comparison revealed a significant difference in bacterial density between below and above ground. Endophytic bacterial isolates (605) were identified, grouped into 24 genera and three phyla. Proteobacteria was the most represented (67.4%) followed by Firmicutes (23.7%) and Actinobacteria (4.3%). …
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Roles and Interplay of Flavonoids, Reactive Oxygen Species, and Cytokinin in the Early Infection of Medicago truncatula by Sinorhizobium meliloti
… by which legumes are infected by symbiotic, nitrogen-fixing bacteria (rhizobia) may prove crucial in the pursuit of bio-engineering nitrogen-fixation in current food crops, and as a result, reducing reliance on nitrogen fertilisers. In this thesis, I have examined the roles and interplay of …
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Biomarkers (lipids, fatty acids and stable isotopes) to examine diet of the sea urchin Evechinus chloroticus.
… living on the seaweeds or possibly has nitrogen-fixing bacteria resident in the gut. A comparison of the fatty acid composition of two different species of sea urchins, E. chloroticus and A. dufresnii, from different geographical locations revealed that not only the diet, but also the …
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Interactive effects of elevated carbon dioxide concentration and water availability on field-grown soybean (Glycine max)
… and, in the case of legumes, the symbiosis with nitrogen-fixing bacteria. These knowledge gaps were addressed at the soybean Free-Air CO2 Enrichment (soyFACE) facility, where soybean was grown in the field at ambient [CO2] or elevated [CO2], as predicted for the middle of this century. I analyzed …
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Investigation of Miscanthus associated microbiome: effects of biotic and abiotic factors
… of soil fertility. Beneficial microbes, such as nitrogen-fixing bacteria, contribute to plant yield and fitness, representing under-explored plant nutrient sources. Optimizing the positive interactions between Miscanthus species and associated bacteria has high potential to support sustainable …
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Ecology of Root Nodule Bacterial Diversity: Implications for Soybean Growth
… such as soybean (Glycine max L. Merr) with nitrogen (N) needed for protein synthesis through biological nitrogen fixation (BNF). Through BNF, these bacteria such as Bradyrhizobium that reside in soybean root nodules, convert atmospheric nitrogen (N2) into ammonia (NH3/ NH4), a form that is …
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