Relevant bibliographies by topics / Rhizobium

Academic literature on the topic 'Rhizobium'

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Published: 4 June 2021
Last updated: 18 May 2024

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Journal articles on the topic "Rhizobium"

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SHAHRAJABIAN, Mohamad H., Wenli SUN, and Qi CHENG. "The importance of Rhizobium, Agrobacterium, Bradyrhizobium, Herbaspirillum, Sinorhizobium in sustainable agricultural production." Notulae Botanicae Horti Agrobotanici Cluj-Napoca 49, no. 3 (September 10, 2021): 12183. http://dx.doi.org/10.15835/nbha49312183.

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Rhizobia which are soil bacteria capable of symbiosis with legume plants in the root or stem nodules and perform nitrogen fixation. Rhizobial genera include Agrobacterium, Allorhizobium, Aminobacter, Azorhizobium, Bradyrhizobium, Devosia, Mesorhizobium, Methylobacterium, Microvirga, Ochrobacterum, Phyllobacterium, Rhizobium, Shinella and Ensifer (Sinorhizobium). Review of the literature was carried out using the keywords Rhizobium, Agrobacterium, Bradyrhizobium, Herbaspirillum and Sinorhizobium. Rhizobial nodulation symbioses steps are included flavonoid signaling, Nod factor induction, and Nod factor perception, root hair responses, rhizobial infection, cell division and formation of nitrogen-fixing nodule. Rhizobium improves sustainable production by boosting organic nitrogen content.
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Op den Camp, Rik H. M., Elisa Polone, Elena Fedorova, Wim Roelofsen, Andrea Squartini, Huub J. M. Op den Camp, Ton Bisseling, and René Geurts. "Nonlegume Parasponia andersonii Deploys a Broad Rhizobium Host Range Strategy Resulting in Largely Variable Symbiotic Effectiveness." Molecular Plant-Microbe Interactions® 25, no. 7 (July 2012): 954–63. http://dx.doi.org/10.1094/mpmi-11-11-0304.

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The non-legume genus Parasponia has evolved the rhizobium symbiosis independent from legumes and has done so only recently. We aim to study the promiscuity of such newly evolved symbiotic engagement and determine the symbiotic effectiveness of infecting rhizobium species. It was found that Parasponia andersonii can be nodulated by a broad range of rhizobia belonging to four different genera, and therefore, we conclude that this non-legume is highly promiscuous for rhizobial engagement. A possible drawback of this high promiscuity is that low-efficient strains can infect nodules as well. The strains identified displayed a range in nitrogen-fixation effectiveness, including a very inefficient rhizobium species, Rhizobium tropici WUR1. Because this species is able to make effective nodules on two different legume species, it suggests that the ineffectiveness of P. andersonii nodules is the result of the incompatibility between both partners. In P. andersonii nodules, rhizobia of this strain become embedded in a dense matrix but remain vital. This suggests that sanctions or genetic control against underperforming microsymbionts may not be effective in Parasponia spp. Therefore, we argue that the Parasponia-rhizobium symbiosis is a delicate balance between mutual benefits and parasitic colonization.
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NISTE, Monica, Roxana VIDICAN, Ioan ROTAR, and Rodica POP. "The Effect of pH Stress on the Survival of Rhizobium Trifolii and Sinorhizobium Meliloti in Vitro." Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Agriculture 70, no. 2 (November 26, 2013): 449–50. http://dx.doi.org/10.15835/buasvmcn-agr:9811.

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Nitrogen-fixing symbiotic bacteria known as rhizobia can exist in different soils and adapt to different environmental conditions. The aim of this study was to determine the impact of pH on the growth of Rhizobium trifolii and Sinorhizobium meliloti. Rhizobial species were isolated using yeast extract mannitol agar medium) in which the pH values were adjusted to 5.0, 6.0, 8.0 and 9.0 by adding HCl and NaOH. The optimum pH for rhizobia is neutral or slightly alkaline (pH 8) and they are more sensitive to acidity. Sinorhizobium meliloti developed better in an acid medium compared to Rhizobium trifolii.
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Aguilar, O. Mario, María Verónica López, Pablo M. Riccillo, Ramón A. González, Marcela Pagano, Daniel H. Grasso, Alfred Pühler, and Gabriel Favelukes. "Prevalence of the Rhizobium etli-Like Allele in Genes Coding for 16S rRNA among the Indigenous Rhizobial Populations Found Associated with Wild Beans from the Southern Andes in Argentina." Applied and Environmental Microbiology 64, no. 9 (September 1, 1998): 3520–24. http://dx.doi.org/10.1128/aem.64.9.3520-3524.1998.

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ABSTRACT A collection of rhizobial isolates from nodules of wild beans,Phaseolus vulgaris var. aborigineus, found growing in virgin lands in 17 geographically separate sites in northwest Argentina was characterized on the basis of host range, growth, hybridization to a nifH probe, analysis of genes coding for 16S rRNA (16S rDNA), DNA fingerprinting, and plasmid profiles. Nodules in field-collected wild bean plants were largely dominated by rhizobia carrying the 16S rDNA allele of Rhizobium etli. A similar prevalence of the R. etli allele was observed among rhizobia trapped from nearby soil. Intragroup diversity of wild bean isolates with either R. etli-like or Rhizobium leguminosarum bv. phaseoli-like alleles was generally found across northwest Argentina. The predominance of the R. etliallele suggests that in this center of origin of P. vulgaris the coevolution of Rhizobium spp. and primitive beans has resulted in this preferential symbiotic association.
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Mendoza-Suárez, Marcela A., Barney A. Geddes, Carmen Sánchez-Cañizares, Ricardo H. Ramírez-González, Charlotte Kirchhelle, Beatriz Jorrin, and Philip S. Poole. "Optimizing Rhizobium-legume symbioses by simultaneous measurement of rhizobial competitiveness and N2 fixation in nodules." Proceedings of the National Academy of Sciences 117, no. 18 (April 21, 2020): 9822–31. http://dx.doi.org/10.1073/pnas.1921225117.

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Legumes tend to be nodulated by competitive rhizobia that do not maximize nitrogen (N2) fixation, resulting in suboptimal yields. Rhizobial nodulation competitiveness and effectiveness at N2 fixation are independent traits, making their measurement extremely time-consuming with low experimental throughput. To transform the experimental assessment of rhizobial competitiveness and effectiveness, we have used synthetic biology to develop reporter plasmids that allow simultaneous high-throughput measurement of N2 fixation in individual nodules using green fluorescent protein (GFP) and barcode strain identification (Plasmid ID) through next generation sequencing (NGS). In a proof-of-concept experiment using this technology in an agricultural soil, we simultaneously monitored 84 different Rhizobium leguminosarum strains, identifying a supercompetitive and highly effective rhizobial symbiont for peas. We also observed a remarkable frequency of nodule coinfection by rhizobia, with mixed occupancy identified in ∼20% of nodules, containing up to six different strains. Critically, this process can be adapted to multiple Rhizobium-legume symbioses, soil types, and environmental conditions to permit easy identification of optimal rhizobial inoculants for field testing to maximize agricultural yield.
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ZAMAN-ALLAH, M., B. SIFI, B. L'TAIEF, M. H. EL AOUNI, and J. J. DREVON. "RHIZOBIAL INOCULATION AND P FERTILIZATION RESPONSE IN COMMON BEAN (PHASEOLUS VULGARIS) UNDER GLASSHOUSE AND FIELD CONDITIONS." Experimental Agriculture 43, no. 1 (January 2007): 67–77. http://dx.doi.org/10.1017/s0014479706004236.

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Osmotic constraints, nutrient deficiencies, especially phosphorus, and the lack of efficient strains of rhizobia in Mediterranean soils are major factors limiting symbiotic nitrogen fixation and yield in common bean (Phaseolus vulgaris). In order to improve yields, we investigated responses to rhizobial inoculation and P fertilization under glasshouse and field conditions with two bean cultivars, Coco blanc and BAT477. The nodulation test, using a hydroponic system in a glasshouse, revealed strong variability among 22 rhizobium strains of various origins, in their symbiotic efficiency, compared with Rhizobium tropici CIAT899. The introduced strains proved to be more efficient although some local rhizobia revealed high potential efficiencies. Glasshouse trials showed a significant effect of inoculation and P supply on nodulation, N content and shoot dry weight that varied with rhizobial strain. Field trials substantiated the glasshouse observations and emphasized the effects of cultivar-rhizobia interactions on symbiotic parameters and yields. It is concluded that inoculation with suitable rhizobia with supply of additional P is a technology that may improve symbiotic nitrogen fixation and yield in common bean in some soils under a Mediterranean climate.
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Milićević, Milica, Dušica Delić, Nataša Rasulić, Mila Pešić, Merisa Avdović, Olivera Stajković-Srbinović, and Biljana Nikolić. "Production of indolic compounds by rhizobial bacteria." Zemljiste i biljka 72, no. 2 (2023): 48–59. http://dx.doi.org/10.5937/zembilj2302048m.

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Rhizobial bacteria, besides nitrogen fixation in symbiosis with legumes, can colonize the roots of nonlegumes and promote their growth by different mechanisms, independently of N2 fixation. Owing to this, rhizobia are considered a plant growth-promoting rhizobacteria (PGPR). Some of the mechanisms of PGPR activity are phytohormone production. Selection of rhizobia which possess some of PGP traits in vitro is an important step prior to testing their effects on plants in controlled conditions or field. In this work the ability of indole-3-acid (IAA) production, one of the most important phytohormone of the auxin class, was evaluated in different rhizobial strains. The investigated rhizobial strains were isolated from alfalfa (belonged to the genera Ensifer and Rhizobium) and from soybean (Bradyrhizobium and Rhizobium). Strains of all investigated genera produced IAA in the presence of L-tryptophan as precursor, where Ensifer strains produced the highest amount of IAA (more than 200 µg ml-1 ), followed by Rhizobium, while Bradyrhizobium strains produced the least amount of IAA (with some exceptions up to 15 µg ml-1 ). With the increase of L-tryptophan concentration, the amount of IAA produced usually grew. Strains with high IAA production indicate their plant growth promoting potential and represent the candidates for evaluation of their effects in non-legumes in controlled and field conditions.
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Mateos, Pedro F., David L. Baker, Maureen Petersen, Encarna Velázquez, José I. Jiménez-Zurdo, Eustoquio Martínez-Molina, Andrea Squartini, Guy Orgambide, David H. Hubbell, and Frank B. Dazzo. "Erosion of root epidermal cell walls by Rhizobium polysaccharide-degrading enzymes as related to primary host infection in the Rhizobium–legume symbiosis." Canadian Journal of Microbiology 47, no. 6 (June 1, 2001): 475–87. http://dx.doi.org/10.1139/w01-039.

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A central event of the infection process in the Rhizobium–legume symbiosis is the modification of the host cell wall barrier to form a portal of entry large enough for bacterial penetration. Transmission electron microscopy (TEM) indicates that rhizobia enter the legume root hair through a completely eroded hole that is slightly larger than the bacterial cell and is presumably created by localized enzymatic hydrolysis of the host cell wall. In this study, we have used microscopy and enzymology to further clarify how rhizobia modify root epidermal cell walls to shed new light on the mechanism of primary host infection in the Rhizobium–legume symbiosis. Quantitative scanning electron microscopy indicated that the incidence of highly localized, partially eroded pits on legume root epidermal walls that follow the contour of the rhizobial cell was higher in host than in nonhost legume combinations, was inhibited by high nitrate supply, and was not induced by immobilized wild-type chitolipooligosaccharide Nod factors reversibly adsorbed to latex beads. TEM examination of these partially eroded, epidermal pits indicated that the amorphous, noncrystalline portions of the wall were disrupted, whereas the crystalline portions remained ultrastructurally intact. Further studies using phase-contrast and polarized light microscopy indicated that (i) the structural integrity of clover root hair walls is dependent on wall polymers that are valid substrates for cell-bound polysaccharide-degrading enzymes from rhizobia, (ii) the major site where these rhizobial enzymes can completely erode the root hair wall is highly localized at the isotropic, noncrystalline apex of the root hair tip, and (iii) the degradability of clover root hair walls by rhizobial polysaccharide-degrading enzymes is enhanced by modifications induced during growth in the presence of chitolipooligosaccharide Nod factors from wild-type clover rhizobia. The results suggest a complementary role of rhizobial cell-bound glycanases and chitolipooligosaccharides in creating the localized portals of entry for successful primary host infection.Key words: Rhizobium leguminosarum, cellulase, cell wall, chitolipooligosaccharide, clover, root hair.
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Materon, L. A., J. D. H. Keatinge, D. P. Beck, N. Yurtsever, K. Karuc, and S. Altuntas. "The Role of Rhizobial Biodiversity in Legume Crop Productivity in the West Asian Highlands." Experimental Agriculture 31, no. 4 (October 1995): 485–91. http://dx.doi.org/10.1017/s0014479700026466.

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SUMMARYThe native rhizobia capable of symbiosis with annually-sown food and forage legume crops in the Turkish highlands were surveyed and estimates made of the numbers and nitrogen fixing efficiency of native Rhizobium leguminosarum with Turkish cultivars of lentil (Lens culinaris Medik.) and vetch (Vicia sativa L.). Native rhizobia were present in medium to high numbers in most samples but the nitrogen fixation efficiency of at least half of the isolates was poor. Vetch was somewhat less specific in its rhizobial compatibility than lentil, suggesting a potential for artificial inoculation to improve the productivity and sustainability of cropping in both species especially in areas of central and eastern Anatolia where legumes are not traditionally grown.Biodiversidad en el Rhizobium leguminosarum
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Castellano-Hinojosa, Antonio, Christoph Mora, and Sarah L. Strauss. "Native Rhizobia Improve Plant Growth, Fix N2, and Reduce Greenhouse Emissions of Sunnhemp More than Commercial Rhizobia Inoculants in Florida Citrus Orchards." Plants 11, no. 22 (November 8, 2022): 3011. http://dx.doi.org/10.3390/plants11223011.

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Sunnhemp (Crotalaria juncea L.) is an important legume cover crop used in tree cropping systems, where there is increased interest by growers to identify rhizobia to maximize soil nitrogen (N) inputs. We aimed to isolate and identify native rhizobia and compare their capabilities with non-native rhizobia from commercial inoculants to fix atmospheric dinitrogen (N2), produce and reduce nitrous oxide (N2O), and improve plant growth. Phylogenetic analyses of sequences of the 16S rRNA and recA, atpD, and glnII genes showed native rhizobial strains belonged to Rhizobium tropici and the non-native strain to Bradyrhizobium japonicum. Plant nodulation tests, sequencing of nodC and nifH genes, and the acetylene-dependent ethylene production assay confirmed the capacity of all strains to nodulate sunnhemp and fix N2. Inoculation with native rhizobial strains resulted in significant increases in root and shoot weight and total C and N contents in the shoots, and showed greater N2-fixation rates and lower emissions of N2O compared to the non-native rhizobium. Our results suggest that native rhizobia improve plant growth, fix N2, and reduce greenhouse emissions of sunnhemp more than commercial rhizobia inoculants in Florida citrus orchards.
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Dissertations / Theses on the topic "Rhizobium"

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Eggleston, Gillian. "Rhizobium gelling polysaccharides." Thesis, Cranfield University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317909.

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Bardin, Sylvie D. "Phosphate uptake in Rhizobium meliloti." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0011/NQ30071.pdf.

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Finnie, Christine. "Protein secretion by Rhizobium leguminosarum." Thesis, University of East Anglia, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361420.

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WISNIEWSKI, JEAN-PIERRE. "Symbiose : lectines de rhizobium lupini." Orléans, 1993. http://www.theses.fr/1993ORLE2041.

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Les bacteries du genre rhizobium peuvent interagir avec les plantes legumineuses pour etablir une symbiose fixatrice d'azote qui permet la nutrition azotee de la plante a partir de l'azote de l'air. Cette association symbiotique se traduit par le developpement d'un organe racinaire nouveau, le nodule, que les bacteries colonisent. L'une des etapes cles de la nodulation implique l'attachement des bacteries fixatrices d'azote sur les cellules vegetales avant leur penetration au sein des tissus racinaires. En nous interessant plus particulierement aux interactions glycannes/proteines, nous nous sommes proposes, au cours de ce travail, de montrer l'existence de lectines associees a la surface de rhizobium lupini. Une etude spectrofluorimetrique utilisant les neoglycoproteines fluoresceinylees, ainsi que des tests d'hemagglutination, nous ont permis de mettre en evidence des activites lectine s a ph 5,0. Par chromatographie d'affinite, nous avons purifie une lectine specifique de l'-l-fucose a partir de la souche ll13. Cette proteine a une masse moleculaire relative de 19 000 et presente un point isoelectrique de 6,7. Dans le cadre de l'etude des interactions entre r. Lupini et son partenaire hote, nous avons extrait et fractionne des exsudats de lupinus albus. Nous avons montre que des composes phenoliques presents dans ces exsudats pouvaient moduler les activites lectines associees aux souches de r. Lupini. Ces exsudats ont egalement un effet chimioattractant sur les bacteries
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Poole, Philip. "Amino acid metabolism in Rhizobium." Thesis, Poole, Philip (1986) Amino acid metabolism in Rhizobium. PhD thesis, Murdoch University, 1986. https://researchrepository.murdoch.edu.au/id/eprint/51728/.

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Addition of a broad range of L-amino acids and several D-amino acids to washed cells of Rhizobium leguminosarum strains WU235 and MNF3841 grown on glucose/NH4Cl elicited a low rate of O2 consumption. L-Glutamate, L-glutamine, L-aspartate, L-asparagine, L-alanine or L-histidine served as the sole source of nitrogen and carbon for growth of strain WU235 and each caused a several-fold increase in the amino acid dependent O2 consumption. In all these cultures excess ammonia was liberated, with the quantity depending on the number of nitrogen atoms per amino acid molecule. A very high dicarboxylic acid dependent O2 consumption in cells of WU235 grown on aspartate was found to be due to the presence of aspartase (EC 4.3.1.1). R. leguminosarum WU235 only expressed aspartase when grown on L-aspartate or L-asparagine as the sole carbon source. Cells grown on glucose plus L-aspartate, or fumarate plus L-aspartate, did not express aspartase. Although these results suggested catabolite control of an inducible enzyme, induction of aspartase could not be demonstrated. Aspartase-producing cells continued to synthesize the enzyme after repeated subculture on glucose plus NH4Cl. Cells grown in glucose plus NH4Cl and plated onto aspartate produced different colony sizes; the larger (0.1% of the total) expressed aspartase, while the smaller did not. At dilutions sufficient to exclude the large aspartase-producing colonies, all initial colonies were the same size. They later developed papillae or became cluster colonies and produced aspartase. The data suggest that strain WU235 is unable to produce aspartase unless a mutation occurs which leads to constitutive enzyme synthesis. Rhizobium leguminosarum MNF3841 grown on glucose/NH4Cl constitutively transported several L-amino acids. Transport rates were elevated 1.5-4 fold after growth in the absence of anmonia. Uptake of L-glutamate, L-glutamine, L-asparagine and L-leucine was inhibited to varying extents by a broad range of L-amino acids. The use of structural analogues of Lglutanvate and metabolic inhibitors suggested that L-glutamate transport was an active process requiring the L-isaner to have a free alpha hydrogen and a free amino group. Cells loaded with either L-(14C) leucine or L-(14C) glutamate exhibited exchange with a wide range of amino acids. The apparent Km for L-glutamate transport was 81 nM and both Laspartate and L-alanine were competitive inhibitors of Lglutamate uptake. Thus there appears to be an extremely high affinity carrier for L-glutamate that is not only very sensitive to inhibition by L-aspartate but also capable of being inhibited by a broad range of amino acids at an order of magnitude higher concentration. Batch cultures of R. leguminosarum MNF3841, R. leguminosarum WU235, R. phaseoli WU15, R. trifolii TA1 and R. meliloti WU38 used amnonia faster than glutamate when presented with an equimolar mixture of the two. Only the cowpea strain NGR234 used both nitrogen sources at the same rate. R. leguminosarum MNF3841 grew faster on ammonia than on glutamate as the nitrogen source. In chemostat culture grown under phosphate limitation strain MNF3841 did not release excess ammonia when grown on either mannitol/L-glutamate or fumarate/L-glutamate, showing that L-glutamate catabolism was tightly regulated to meet the cells nitrogen requirement. Furthermore the rate of consumption of ammonia was similar to that for L-glutamate when either was supplied as the sole nitrogen source. However with L-histidine or L-alanine as the nitrogen source large quantities of excess ammonia were released. When chemostat cultures of R. leguminosarum MNF3841 were supplied with an equimolar mixture of ammonia and Lglutamate, 81-100% of the nitrogen consumed was ammonia. Similarly with mixtures of L-glutamate/L-histidine or Lglutamate/ L-alanine almost no L-glutamate was consumed, a result attributable to the release of excess ammonia from either L-histidine or L-alanine. The use of 14C labelled fructose or L-glutamate suggested that the intra and extracellular L-glutamate pools were isolated. This indicated that the ammonia preference must be exerted by a restriction in Lglutamate transport. L-Glutamate transport rates were low in L-glutamate/NH4Cl containing chemostats, which suggests ammonia restricts L-glutamate transport both by repression and perhaps by inhibition by seme metabolic intermediate.
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Dooley, John J. "Molecular techniques for rhizobium identification." Thesis, University of Bath, 1997. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338595.

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Miller, Lance Delano. "Characterization of the Chemotaxis System of the Endosymbiotic Bacterium Rhizobium leguminosarum." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19707.

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Chemotaxis is the process by which motile bacteria navigate chemical gradients in order to position themselves in optimum environments for growth and metabolism. Sensory input from both the external environment and the internal cellular environment are sensed by chemotaxis transducers and transduced to a two-component system whose output interacts with the flagellum thereby regulating motility. Chemotaxis has been implicated in establishing the endosymbiotic relationship between the motile alpha-proteobacterium Rhizobium leguminosarum biovar viciae and its host Pisum sativa, the pea plant. An approach combing bioinformatical sequence analysis, molecular genetics, and behavioral analysis was used to characterize the chemotaxis system of R. leguminosarum and determine its contribution to this bacterium s lifestyle. A genome search revealed the presence of two chemotaxis gene clusters, che1 and che2. Homologs of each che cluster are major chemotaxis operons controlling flagellar motility in other bacterial species. For this reason we sought to determine the contribution of each che cluster to chemotaxis in R. leguminosarum. We found that while both che clusters contribute to the regulation of motility, che1 is the major che cluster controlling chemotaxis. Using competitive nodulation assays we determined that che1, but not che2, is essential for competitive nodulation. The major che cluster, che1, encodes a chemotaxis transducer, IcpA-Rl, with a globin coupled sensor domain. Chemotaxis transducers with a globin coupled sensor domain comprise a large class of proteins found in bacteria and archaea. These proteins have been shown to bind heme and sense oxygen and are therefore termed HemATs for heme-binding aerotaxis transducers. However, sequence analysis of IcpA-Rl reveals that it lacks the requisite amino acid residues for heme-binding and is therefore unlikely to sense oxygen. We present evidence that IcpA-Rl is likely an energy transducer and represents a novel function of the globin coupled sensor domain in sensing energy related parameters.
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Thorne, Stephen Howard. "Stationary phase survival of Rhizobium leguminosarum." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265401.

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Seaman, Jonathan. "Signature-tagged mutagenesis in Rhizobium leguminosarum." Thesis, University of Reading, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499374.

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Rhizobia are a diverse group of symbiotic alpha-proteobacterial diazotrophs which enter a relationship with specific leguminous plants, in which the plant supplies the bacteria with required compounds whilst the bacteria reduce atmospheric nitrogen into ammonia that the plant uses as a nitrogen source. Modification of rhizobial strains has produced mutants more effective at fixing nitrogen, which in turn results in an increase in biomass of host plants under laboratory conditions but these strains are frequently out competed by wild-type strains in field studies or lost in the intervening years of a crop rotation. This study aimed to establish a library of mutants and a system for screening these strains en masse to identify some of the genes involved in competitive rhizosphere colonization in Rhizobium leguminosam.
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Fox, Marc A. "Adaptation of Rhizobium to environmental stress." Thesis, University of Reading, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427836.

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Books on the topic "Rhizobium"

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Somasegaran, P. Handbook for Rhizobia: Methods in legume-rhizobium technology. New York: Springer-Verlag, 1994.

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Hansen, Alexander P., Devendra K. Choudhary, Pawan Kumar Agrawal, and Ajit Varma, eds. Rhizobium Biology and Biotechnology. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-64982-5.

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Somasegaran, P. Methods in legume-rhizobium technology. Paia, Maui, HI, USA: University of Hawaii NifTAL Project and MIRCEN, Dept. of Agronomy and Soil Science, Hawaii Institute of Tropical Agriculture and Human Resources, College of Tropical Agriculture and Human Resources, 1985.

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Keyser, Harold H. Beltsville Rhizobium Culture Collection catalog. [Beltsville, Md.?]: U.S. Dept. of Agriculture, Agricultural Research Service, 1987.

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International Livestock Centre for Africa. Soil Science & Plant Nutrition Section. Rhizobium germplasm resources at ILCA. Addis Ababa, Ethiopia: Soil Science & Plant Nutrition Section, International Livestock Centre for Africa, 1992.

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Zhongguo gen liu jun. Beijing: Ke xue chu ban she, 2011.

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P, Rupela O., and International Crops Research Institute for the Semi-Arid Tropics., eds. Rhizobium germplasm resources at ICRISAT Center. Patancheru: ICRISAT, 1991.

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Latchford, J. W. Genetic analysis of exopolysaccharide synthesis in Rhizobium. Norwich: University of East Anglia, 1990.

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Jamaluddin. Application of Rhizobium in forest tree species. Jabalpur: Tropical Forest Research Institute, Indian Council of Forestry Research and Education, 1997.

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Borthakur, Dulal. Molecular genetics of exopolysaccharide synthesis in Rhizobium. Norwich: University of East Anglia, 1986.

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Book chapters on the topic "Rhizobium"

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Weaver, R. W., and L. R. Frederick. "Rhizobium." In Agronomy Monographs, 1043–70. Madison, WI, USA: American Society of Agronomy, Soil Science Society of America, 2015. http://dx.doi.org/10.2134/agronmonogr9.2.2ed.c49.

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Evans, H. J., P. J. Bottomley, and W. E. Newton. "Rhizobium - Competition." In Nitrogen fixation research progress, 395–402. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5175-4_54.

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Evans, H. J., P. J. Bottomley, and W. E. Newton. "Rhizobium - Survival." In Nitrogen fixation research progress, 403–8. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5175-4_55.

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Evans, H. J., P. J. Bottomley, and W. E. Newton. "Rhizobium - General." In Nitrogen fixation research progress, 409–18. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5175-4_56.

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Honeycutt, Rhonda J., and Bruno W. S. Sobral. "Rhizobium meliloti." In Bacterial Genomes, 719–21. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-6369-3_74.

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Taylor, N. L., and K. H. Quesenberry. "Rhizobium Relationships." In Red Clover Science, 130–40. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-015-8692-4_11.

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Palacios, Rafael, Susana Brom, Guillermo Dávila, Margarita Flores, Ma Lourdes Girard, David Romero, and Tomasz Stepkowski. "Gene Amplification in Rhizobium." In New Horizons in Nitrogen Fixation, 581–85. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-017-2416-6_52.

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Thompson, J. A. "Selection of Rhizobium Strains." In Nitrogen Fixation by Legumes in Mediterranean Agriculture, 207–23. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-1387-5_22.

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Twelker, Sunny, Ivan J. Oresnik, and Michael F. Hynes. "Bacteriocins of Rhizobium Leguminosarum." In Highlights of Nitrogen Fixation Research, 105–8. Boston, MA: Springer US, 1999. http://dx.doi.org/10.1007/978-1-4615-4795-2_20.

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McDermott, Timothy R. "Phosphate Metabolism in Rhizobium." In Highlights of Nitrogen Fixation Research, 45–47. Boston, MA: Springer US, 1999. http://dx.doi.org/10.1007/978-1-4615-4795-2_9.

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Conference papers on the topic "Rhizobium"

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Adjuik, Toby A., Sue E. Nokes, and Michael D. Montross. "Lignin-alginate-based Biopolymers for the Bioencapsulation of Rhizobium." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/ojme7252.

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Cell immobilization provides a physical protection for viable Rhizobial cells in a confined carrier material allowing for the cells’ slow release into the environment. While several petroleum-based polymers have been tested for encapsulating microbes, they are often less biodegradable in the environment and may adversely affect viability of cells. One material that is biobased and has been underutilized for Rhizobium cell carriers is lignin. The present study was conducted to evaluate the feasibility of using lignin-alginate biopolymers with a starch additive to bioencapsulate and release Rhizobium cells.Rhizobium cells were bioencapsulated into the lignin-alginate starch beads and their efficiency i.e [(log of number of cells in wet beads/log of number of cells in solution matrix) x 100%] and release kinetics were determined. Light microscopy and scanning electron microscopy were also used to investigate the surface morphology of the beads. Our results show that all variations (alginate, lignin-alginate, and lignin-alginate with starch additive) of the wet bioencapsulated beads achieved a similar efficiency 97%. However, the presence of starch in the lignin-alginate beads increased the survival of Rhizobium cells after drying from 61 to 84% compared to only alginate encapsulation. These results imply that lignin, a readily available biopolymer is a potential component for the manufacture of carrier materials for encapsulating Rhizobium cells.
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Bhattacharya, Radha. "Environmental impact on Rhizobium sp. cells." In Proceedings of the III International Conference on Environmental, Industrial and Applied Microbiology (BioMicroWorld2009). WORLD SCIENTIFIC, 2010. http://dx.doi.org/10.1142/9789814322119_0036.

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Hasanah, Ifroh Hatun, and Iqbal Erdiansyah. "Pengaruh Inokulasi Rhizobium spp terhadap Pertumbuhan dan Hasil Produksi Kacang Tanah pada Cekaman Kekeringan." In Seminar Nasional Semanis Tani Polije 2020. Politeknik Negeri Jember, 2020. http://dx.doi.org/10.25047/agropross.2020.42.

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Bondowoso merupakan salah satu kota di Jawa Timur, memiliki kawasan budidaya tadah hujan, sawah dan hutan.Sektor pertanian merupakan sektor unggulan.Kacang tanah merupakan salah satu tanaman yang dibudidayakan.produksi kacang tanah di Bondowoso mengalami penurunan. Penurunan produksi kacang tanah salah satunya dapat disebabkan oleh kekurangan air untuk proses pertumbuhan tanaman sehingga berpengaruh terhadap produksi kacang tanah. Teknologi yang bisa digunakan salah satunya adalah rekayasa irigasi pada lahan tadah hujan, selain rekayasa irigasi perlu adanya rekayasa pemupukan dengan menggunakan Rhizobium spp. Aplikasi inokulumRhizobium spp dengan perlakuan dengan waktu penyiraman 2 hari sekali (P1), 4 hari sekali (P2), 6 hari sekali (P3) dan 8 hari sekali (P4). Hasil percobaan aplikasi Rhizobium spp pada tanaman kacang tanah dengan cekaman kekeringan memberikan efek terhadap pertumbuhan dan produksi kacang tanah. Pengaruh aplikasi Rhizobium spp meningkatkan tinggi tanaman, berat polong basah, berat polong kering, berat biji kering, berat bintil akar.Rhizobium spp dapat memfiksasi nitrogen bebas di udara pada kondisi cekaman kekeringan.Rhizobium dapat menyediakan hara bagi tanaman dalam bentuk NO3-, tumbuhan menggunakan NO3-untuk fotosintesis dan hasil produk berupa protein.Perlakuan terbaik yaitu penyiraman 2 hari sekali dan penambahan Rhizobium spp dengan konsentrasi 20 ml/l.
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Urban, James E. "Microgravity effects on the legume/Rhizobium symbiosis." In AIP Conference Proceedings Volume 387. ASCE, 1997. http://dx.doi.org/10.1063/1.52122.

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Lobanov, A. N., and T. V. Polyudova. "Cultivation of Rhizobium leguminosarum to produce exopolysaccharide." In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.150.

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While studying the bacteria Rhizobium leguminosarum from different sources, a strain was isolated. Its growth on a liquid nutrient medium is accompanied by the accumulation of a significant amount of exopolysaccharide substance.
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Nasir, Adam Izzuddin, Aliyu Adamu, Yilmaz Kaya, Mohamed Faraj Edbeib, and Fahrul Huyop. "Putative Dehalogenase uptake gene from Rhizobium sp. RC1." In Proceedings of the International Conference on Science and Education and Technology 2018 (ISET 2018). Paris, France: Atlantis Press, 2018. http://dx.doi.org/10.2991/iset-18.2018.3.

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Prisacari, Svetlana, Vasile Todiraş, and Serghei Corcimaru. "The influence of nanomagnetite on the processes of growth, development, and formation of the legume-rhizobia complex in vetch plants under soil conditions of plastics pollution." In 5th International Scientific Conference on Microbial Biotechnology. Institute of Microbiology and Biotechnology, Republic of Moldova, 2022. http://dx.doi.org/10.52757/imb22.27.

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The Republic of Moldova suffers from the problem of environmental pollution by plastics, including by the low-density polyethylene (LDPE). The accumulation of plastics by plants has negative consequences for the food security and sustainable development of the agriculture. It is suggested that over time soil pollution by plastics can threaten the successful functioning of the entire agricultural system. The negative consequences of soil pollution by plastics impose the need of developing measures of remediation. Due to the lack of efficient chemical and physical methods for destroying plastics in soil, the attention has recently been directed toward developing biological degradation techniques, including the ones based on application of phytoremediation and nanophytoremediation. However, the potential of these techniques in the cases of soil pollution by LDPE is understudied. The aim of this work was to explore the possibility of using nanomagnetite and vetch plants bacterized by the Rhizobium leguminosarum K2 strain for remediation of soils contaminated by LDPE. The introduction into soil of a finely chopped LDPE (5 g/kg) and nanomagnetite (25 mg/kg of soil) resulted in increases in the total length of plants (roots included), plant height, and the accumulation of dry biomass of 10.6%, 15.4%, and 28.8% respectively. The number of root nodules was higher by 2.2 times. Positive effects were also observed in the two variants where LDPE was introduced without nanomagnetite and the vetch seeds were either inoculated or not inoculated by rhizobia. Comparing to the control, the root length, plant height, and dry mass had 8.2%, 11.7%, and 26, 8% increases respectively. The number of root nodules in these variants was 2.4–2.8 times higher than in the control. Even though not all effects were significant statistically, the general picture showed that the introduction of LDPE into soil had no inhibitory effects on plant productivity and formation of the legumerhizobia complex, and even stimulated them, especially in the cases of seed inoculation by rhizobia and nanomagnetite treatment. The observed formation of healthy legume-rhizobia complexes in the variants where the plant seeds were inoculated by Rhizobium leguminosarum K2 is of a significant importance for plant productivity, as well as for soil fertility. Rhizobia within this symbiosis provide the plants with the nitrogen fixed from the atmosphere, and, in turn, obtain from them the needed organic substrates. It is known that due to the symbiotic nitrogen fixation, the soil annually can receive up to 90-180 kg/ha of nitrogen. The observed stimulation of dry mass accumulation was important too. The fact that the plants and the symbiosis with rhizobia could be stimulated in the presence of LDPE contamination demonstrated the possibility of using the vetch plants as an efficient phytoremediator in cases of soil pollution by plastic waste.
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Kimeklis, А. К., Т. S. Aksenova, G. V. Gladkov, I. G. Kuznetsova, А. L. Sazanova, V. I. Safronova, А. А. Belimov, et al. "Vavilovia formosa rhizobia symbionts belong to Rhizobium leguminosarum bv. viciae species, but form a separate group within it." In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.119.

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Ecological isolation, group separation of hkg and sym genes, along with the results of the sterile tube test demonstrate that symbionts of V. formosa belong to R. leguminosarum bv. viciae species, but form a separate group within it.
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Pérez Salinas, Ruth Narcisa, and Israel Carrillo. "Rhizobium inoculation method and its Andean Lupinus development effect." In 1er Congreso Universal de las Ciencias y la Investigación Medwave 2022;. Medwave Estudios Limitada, 2022. http://dx.doi.org/10.5867/medwave.2022.s2.uta054.

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Rohmani, Risma Wakhidatur, Iqbal Erdiansyah, and FNU Djenal. "Karakteristik Bakteri Rhizobium japonicum Bintil Akar Kedelai pada Cekaman Salinitas Bertingkat." In Seminar Nasional Semanis Tani Polije 2020. Politeknik Negeri Jember, 2020. http://dx.doi.org/10.25047/agropross.2020.41.

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Kenaikan suhu permukaan bumi berimbas pada naiknya permukaan air laut ke daratan, hal inilah yang menyebabkan garam-garam yang dikandung oleh air laut akan mengalami sedimentasi di tanah yang dilewatinya. Tanaman kedelai yang tercekam salin dapat menurunkan hasil produksi tanaman karena garam yang terlarut dapat menurunkanpotensial larutan tanah sehingga tanaman mengalami kekurangan air. Teknologi khusus yang digunakan untuk menunjang pertubuhan dan hasil tanaman kedelai di lahan salin adalah penggunaan pupuk hayati, yang salah satunya berasal dari Rhizobium japonicum.Rhizobium japonicum merupakan bakteri rizosfer yang mampu menguraikan nitrogen bebas di udara menjadi unsur yang mampu terserap oleh tanaman. Nitrogen adalah unsur hara yang sangat penting dalam proses fotosintesis tanaman untuk menghasilkan fotosintat yang berguna untuk pertumbuhan dan produksi yang optimal. Penelitian ini bertujuan untuk mengisolasi dan mengkarakterisasi bakteri Rhizobium japonicum pada tingkat salinitas tertentu pada media YEMA+Congo Red,penelitian ini dilakukan pada bulan Juni 2019 sampai dengan September 2019 di Laboratorium Biosain Politeknik Negeri Jember. Penelitian ini dilakukan dengan menggunakan rancangan non parametrik dengan berbagai macam tingkat cekaman salinitas pada media yaitu: 0 ppm, 1000 ppm, 2500 ppm, 4000 ppm, dan 8000 ppm. Hasil penelitian menunjukkan koloni bakteri Rhizobium japonicum berbentuk bulat cembung berwarna putih sampai merah muda dan ukuran sel 2µ-4µ.
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Reports on the topic "Rhizobium"

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Hollingsworth, Rawle. Cell surface glycoconjugates of Rhizobium and symbiosis. Office of Scientific and Technical Information (OSTI), May 2001. http://dx.doi.org/10.2172/794175.

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Ditta, G. Identification and manipulation of Rhizobium phytohormone genes. Office of Scientific and Technical Information (OSTI), June 1988. http://dx.doi.org/10.2172/7045705.

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Hollingsworth, R. I. (A structural assessment of the role of the cell surface carbohydrates of Rhizobium in the Rhizobium/legume symbiosis). Office of Scientific and Technical Information (OSTI), January 1991. http://dx.doi.org/10.2172/5242472.

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DeJong, Joel L., and Wayne B. Roush. Soybean Yield Response to Rhizobium Inoculation on Converted Grass Pasture. Ames: Iowa State University, Digital Repository, 2012. http://dx.doi.org/10.31274/farmprogressreports-180814-2661.

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Hollingsworth, R. I. [A structural assessment of the role of the cell surface carbohydrates of Rhizobium in the Rhizobium/legume symbiosis]. Progress report, June 1989--June 1991. Office of Scientific and Technical Information (OSTI), December 1991. http://dx.doi.org/10.2172/10148835.

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Mendoza, Jonathan Alberto, Carolina Mazo, Lina Margarita Conn, Álvaro Rincón Castillo, Daniel Rojas Tapias, and Ruth Bonilla Buitrago. Evaluation of phosphate-solubilizing bacteria associated to pastures of Bracharia from acid soils. Corporación Colombiana de Investigación Agropecuaria - AGROSAVIA, 2015. http://dx.doi.org/10.21930/agrosavia.informe.2015.5.

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Rhizobia have been widely known by their capacity to form a symbiotic relationship with legumes and fix atmospheric nitrogen. Recently, however, rhizobia have shown to associate with plants in different botanical families. In this study, we aimed at elucidating the diversity of rhizobia associated to grasses, and determine their capabilities to solubilize phosphate in both lab and greenhouse experiments. Isolation of rhizobia was performed using rhizosphere from Brachiaria brizantha and B. decumbens and a promiscuous legume trap plant (i.e. Vigna unguiculata). Thirty days after inoculation of the trap plant, rhizobia were isolated from nodules using the conventional protocol, classified in basis on their phenotypic features, and molecularly grouped using Amplified Ribosomal DNA Restriction Analysis (ARDRA). Finally, phosphate solubilization assays and greenhouse experiments were carried out on representatives of each ARDRA cluster. The results showed that the diversity of rhizobia varied between both plant species, which suggests that plant exudates significantly determine the composition of the plant microbiome. Surprisingly, most of the isolated associated to B. brizantha rhizosphere exhibited typical attributes of slow-growing rhizobia, whereas rhizobia from B. decumbens displayed a mixed diversity including slow-, intermediate-, and fast-growing rhizobia. Sequencing of 16S rRNA of ARDRA representatives showed that most of the rhizobia isolated from B. brizantha belonged to the Mesorhizobium and Bradyrhizobium genera, while those isolated from B. decumbens were phylogenetically clustered into Rhizobium and Bradyrhizobium. The capability of the isolates to solubilize phosphate was studied using iron and calcium phosphate. We observed that overall Bradyrhizobium exhibited the highest ability to solubilize iron phosphate; by contrast, calcium phosphate was similarly solubilized within representatives of the three genera. In greenhouse experiments, we found that plants inoculated with isolated BT53, BD17 and BD21 exhibited a significantly higher content of phosphorus (p≤0.05). Additionally, dry weight was significantly higher in the treatment inoculated with BT16 isolate (p≤0.05). We conclude that 1) rhizobia is found associated with grasses, 2) plant genotype determines rhizobia diversity 3) rhizobia are able to solubilize phosphorus, and 4) they might be used to promote plant in different plant families. We further believe that further studies will reveal the true role of those old-known legume symbionts in development and growth of other important crops.
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Handelsman, Jo. Determinants of nodulation competitiveness in Rhizobium etli. Final report for period September 30, 1996--September 29, 1999. Office of Scientific and Technical Information (OSTI), January 2000. http://dx.doi.org/10.2172/765240.

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Kapulnik, Yoram, and Donald A. Phillips. Isoflavonoid Regulation of Root Bacteria. United States Department of Agriculture, January 1996. http://dx.doi.org/10.32747/1996.7570561.bard.

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The overall objective of this project was to develop a conceptual framework for enhancing root colonization by beneficial bacteria. To accomplish this aim we tested the hypothesis that production and excretion of the plant phytoalexin medicarpin can be used for creation of a special niche along the legume roots, where beneficial microorganism, such as rhizobium, will have a selective advantage. On the Israeli side it was shown that higher medicarpin levels are exuded following the application of Rhizobium meliloti to the rhizosphere but the specific biochemical pathway governing medicarpin production was not induced significantly enough to support a constant production and excretion of this molecule to the rhizosphere. Furthermore, pathogenic bacteria and chemical elicitors were found to induce higher levels of this phytoalexin and it became important to test its natural abundance in field grown plants. On the US side, the occurrence of flavonoids and nucleosides in agricultural soils has been evaluated and biologically significant quantities of these molecules were identified. A more virulent Agrobacterium tumefaciens strain was isolated from alfalfa (Medicago sativa L.) which forms tumors on a wide range of plant species. This isolate contains genes that increase competitive colonization abilities on roots by reducing the accumulation of alfalfa isoflavonoids in the bacterial cells. Following gene tagging efforts the US lab found that mutation in the bacterial efflux pump operons of this isolate reduced its competitive abilities. This results support our original hypothesis that detoxification activity of isoflavenoids molecules, based on bacterial gene(s), is an important selection mechanism in the rhizosphere. In addition, we focused on biotin as a regulatory element in the rhizosphere to support growth of some rhizosphere microorganisms and designed a bacterial gene construct carrying the biotin-binding protein, streptavidin. Expressing this gene in tobacco roots did not affect the biotin level but its expression in alfalfa was lethal. In conclusion, the collaborative combination of basic and applied approaches toward the understanding of rhizosphere activity yielded new knowledge related to the colonization of roots by beneficial microorganisms in the presence of biological active molecules exuded from the plant roots.
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Phillips, Donald, and Yoram Kapulnik. Using Flavonoids to Control in vitro Development of Vesicular Arbuscular Mycorrhizal Fungi. United States Department of Agriculture, January 1995. http://dx.doi.org/10.32747/1995.7613012.bard.

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Vesicular-arbuscular mycorrhizal (VAM) fungi and other beneficial rhizosphere microorganisms, such as Rhizobium bacteria, must locate and infect a host plant before either symbiont profits. Although benefits of the VAM association for increased phosphorous uptake have been widely documented, attempts to improve the fungus and to produce agronomically useful amounts of inoculum have failed due to a lack of in vitro production methods. This project was designed to extend our prior observation that the alfalfa flavonoid quercetin promoted spore germination and hyphal growth of VAM fungi in the absence of a host plant. On the Israeli side of the project, a detailed examination of changes in flavonoids and flavonoid-biosynthetic enzymes during the early stages of VAM development in alfalfa found that VAM fungi elicited and then suppressed transcription of a plant gene coding for chalcone isomerase, which normally is associated with pathogenic infections. US workers collaborated in the identification of flavonoid compounds that appeared during VAM development. On the US side, an in vitro system for testing the effects of plant compounds on fungal spore germination and hyphal growth was developed for use, and intensive analyses of natural products released from alfalfa seedlings grown in the presence and absence of microorganisms were conducted. Two betaines, trigonelline and stachydrine, were identified as being released from alfalfa seeds in much higher concentrations than flavonoids, and these compounds functioned as transcriptional signals to another alfalfa microsymbiont, Rhizobium meliloti. However, these betaines had no effect on VAM spore germination or hyphal growth i vitro. Experiments showed that symbiotic bacteria elicited exudation of the isoflavonoids medicarpin and coumestrol from legume roots, but neither compound promoted growth or germination of VAM fungi in vitro. Attempts to look directly in alfalfa rhizosphere soil for microbiologically active plant products measured a gradient of nod-gene-inducing activity in R. meliloti, but no novel compounds were identified for testing in the VAM fungal system in vitro. Israeli field experiments on agricultural applications of VAM were very successful and developed methods for using VAM to overcome stunting in peanuts and garlic grown in Israel. In addition, deleterious effects of soil solarization on growth of onion, carrot and wheat were linked to effects on VAM fungi. A collaborative combination of basic and applied approaches toward enhancing the agronomic benefits of VAM asociations produced new knowledge on symbiotic biology and successful methods for using VAM inocula under field conditions
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L’taief, Boulbaba, Sihem Smari, Neila Abdi, and Bouaziz Sifi. Biochemical and Physiological Characterization of Rhizobia Nodulating Vicia faba L. Genotypes. "Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences, June 2019. http://dx.doi.org/10.7546/crabs.2019.06.06.

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