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Sample records for incana root nodules

  1. Nodulation and Rhizobium Population in Root Nodules of Selected ...

    African Journals Online (AJOL)

    Nodulation and rhizobium population in root nodules of 5- year old Leucaena leucocephala; Gliricidia sepium and Acacia mangium were assessed. Nodules of these tree legumes were quantified in terms of their numbers, lateral and vertical distribution while the rhizobium population in cultured nodules was counted as ...

  2. A histochemical study of root nodule development

    NARCIS (Netherlands)

    Wiel, van de C.

    1991-01-01

    In cooperation with soil bacteria of the genera Rhizobium , Bradyrhizobium or Azorhizobium , many members of the legume family are able to form specialized organs on their roots, called root nodules. The bacteria, wrapped up

  3. Root nodule organogenesis : molecular characterization of the zonation central tissue

    NARCIS (Netherlands)

    Yang, W.C.

    1994-01-01

    Legume plants form root nodules by interacting with the soil bacterium, Rhizobium. In these nodules bacteria are able to convert atmospheric nitrogen into ammonia which is used by the host plants as nitrogen source. Therefore symbiotic nitrogen fixation in root nodules

  4. The effect of limited availability of N or water on C allocation to fine roots and annual fine root turnover in Alnus incana and Salix viminalis.

    Science.gov (United States)

    Rytter, Rose-Marie

    2013-09-01

    The effect of limited nitrogen (N) or water availability on fine root growth and turnover was examined in two deciduous species, Alnus incana L. and Salix viminalis L., grown under three different regimes: (i) supply of N and water in amounts which would not hamper growth, (ii) limited N supply and (iii) limited water supply. Plants were grown outdoors during three seasons in covered and buried lysimeters placed in a stand structure and filled with quartz sand. Computer-controlled irrigation and fertilization were supplied through drip tubes. Production and turnover of fine roots were estimated by combining minirhizotron observations and core sampling, or by sequential core sampling. Annual turnover rates of fine roots root production (roots 1-2 mm. Proportionally more C was allocated to fine roots (≤2 mm) in N or water-limited Salix; 2.7 and 2.3 times the allocation to fine roots in the unlimited regime, respectively. Estimated input to soil organic carbon increased by ca. 20% at N limitation in Salix. However, future studies on fine root decomposition under various environmental conditions are required. Fine root growth responses to N or water limitation were less pronounced in Alnus, thus indicating species differences caused by N-fixing capacity and slower initial growth in Alnus, or higher fine root plasticity in Salix. A similar seasonal growth pattern across species and treatments suggested the influence of outer stimuli, such as temperature and light.

  5. The Effect of Indigenous Root-Nodulating Bacteria on Nodulation ...

    African Journals Online (AJOL)

    This study was initiated to isolate and characterize indigenous rhizobia nodulating faba bean, and evaluate symbiotic characteristics between the crop and the rhizobia in major faba bean producing areas in Tigray highlands. Field crops were also surveyed for nodulation in selected sites of seven (7) faba bean growing ...

  6. Effect of exogenous application of rhizopine on lucerne root nodulation

    African Journals Online (AJOL)

    Rhizopine, 3-0 -methyl scyllo-inosamine was applied to the roots of luceme seedling inoculated with either rhizopine synthesizing Sinorhizobium meliloti strain L530 or the non-rhizopine synthesizing strain Rm 1021 . There was an initial delay in nodule formation. A significant increase in the number of nodules formed in ...

  7. Dissecting the Root Nodule Transcriptome of Chickpea (Cicer arietinum L..

    Directory of Open Access Journals (Sweden)

    Chandra Kant

    Full Text Available A hallmark trait of chickpea (Cicer arietinum L., like other legumes, is the capability to convert atmospheric nitrogen (N2 into ammonia (NH3 in symbiotic association with Mesorhizobium ciceri. However, the complexity of molecular networks associated with the dynamics of nodule development in chickpea need to be analyzed in depth. Hence, in order to gain insights into the chickpea nodule development, the transcriptomes of nodules at early, middle and late stages of development were sequenced using the Roche 454 platform. This generated 490.84 Mb sequence data comprising 1,360,251 reads which were assembled into 83,405 unigenes. Transcripts were annotated using Gene Ontology (GO, Cluster of Orthologous Groups (COG and Kyoto Encyclopedia of Genes and Genomes (KEGG metabolic pathways analysis. Differential expression analysis revealed that a total of 3760 transcripts were differentially expressed in at least one of three stages, whereas 935, 117 and 2707 transcripts were found to be differentially expressed in the early, middle and late stages of nodule development respectively. MapMan analysis revealed enrichment of metabolic pathways such as transport, protein synthesis, signaling and carbohydrate metabolism during root nodulation. Transcription factors were predicted and analyzed for their differential expression during nodule development. Putative nodule specific transcripts were identified and enriched for GO categories using BiNGO which revealed many categories to be enriched during nodule development, including transcription regulators and transporters. Further, the assembled transcriptome was also used to mine for genic SSR markers. In conclusion, this study will help in enriching the transcriptomic resources implicated in understanding of root nodulation events in chickpea.

  8. Dissecting the Root Nodule Transcriptome of Chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Kant, Chandra; Pradhan, Seema; Bhatia, Sabhyata

    2016-01-01

    A hallmark trait of chickpea (Cicer arietinum L.), like other legumes, is the capability to convert atmospheric nitrogen (N2) into ammonia (NH3) in symbiotic association with Mesorhizobium ciceri. However, the complexity of molecular networks associated with the dynamics of nodule development in chickpea need to be analyzed in depth. Hence, in order to gain insights into the chickpea nodule development, the transcriptomes of nodules at early, middle and late stages of development were sequenced using the Roche 454 platform. This generated 490.84 Mb sequence data comprising 1,360,251 reads which were assembled into 83,405 unigenes. Transcripts were annotated using Gene Ontology (GO), Cluster of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways analysis. Differential expression analysis revealed that a total of 3760 transcripts were differentially expressed in at least one of three stages, whereas 935, 117 and 2707 transcripts were found to be differentially expressed in the early, middle and late stages of nodule development respectively. MapMan analysis revealed enrichment of metabolic pathways such as transport, protein synthesis, signaling and carbohydrate metabolism during root nodulation. Transcription factors were predicted and analyzed for their differential expression during nodule development. Putative nodule specific transcripts were identified and enriched for GO categories using BiNGO which revealed many categories to be enriched during nodule development, including transcription regulators and transporters. Further, the assembled transcriptome was also used to mine for genic SSR markers. In conclusion, this study will help in enriching the transcriptomic resources implicated in understanding of root nodulation events in chickpea.

  9. Asparagine Biosynthesis in Alfalfa (Medicago sativa L.) Root Nodules.

    Science.gov (United States)

    Snapp, S S; Vance, C P

    1986-10-01

    Rapid direct conversion of exogenously supplied [(14)C]aspartate to [(14)C] asparagine and to tricarboxylic cycle acids was observed in alfalfa (Medicago sativa L.) nodules. Aspartate aminotransferase activity readily converted carbon from exogenously applied [(14)C]aspartate into the tricarboxylic acid cycle with subsequent conversion to the organic acids malate, succinate, and fumarate. Aminooxyacetate, an inhibitor of aminotransferase activity, reduced the flow of carbon from [(14)C]aspartate into tricarboxylic cycle acids and decreased (14)CO(2) evolution by 99%. Concurrently, maximum conversion of aspartate to asparagine was observed in aminooxyacetate treated nodules (30 nanomoles asparagine per gram fresh weight per hour. Metabolism of [(14)C]aspartate and distribution of nodulefixed (14)CO(2) suggest that two pools of aspartate occur in alfalfa nodules: (a) one involved in asparagine biosynthesis, and (b) another supplying a malate/aspartate shuttle. Conversion of [(14)C]aspartate to [(14)C]asparagine was not inhibited by methionine sulfoximine, a glutamine synthetase inhibitor, or azaserine, a glutmate synthetase, inhibitor. The data did not indicate that asparagine biosynthesis in alfalfa nodules has an absolute requirement for glutamine. Radioactivity in the xylem sap, derived from nodule (14)CO(2) fixation, was markedly decreased by treating nodulated roots with aminooxyacetate, methionine sulfoximine, and azaserine. Inhibitors decreased the [(14)C]aspartate and [(14)]asparagine content of xylem sap by greater than 80% and reduced the total amino nitrogen content of xylem sap (including nonradiolabeled amino acids) by 50 to 80%. Asparagine biosynthesis in alfalfa nodules and transport in xylem sap are dependent upon continued aminotransferase activity and an uninterrupted assimilation of ammonia via the glutamine synthetase/glutamate synthase pathway. Continued assimilation of ammonia apparently appears crucial to continued root nodule CO(2) fixation in

  10. Expression of nodule-specific genes in alfalfa root nodules blocked at an early stage of development.

    NARCIS (Netherlands)

    Dickstein, R.; Bisseling, T.; Reinhold, V.N.; Ausubel, F.M.

    1988-01-01

    To help dissect the molecular basis of the Rhizobium-legume symbiosis, we used in vitro translation and Northern blot analysis of nodule RNA to examine alfalfa-specific genes (nodulins) expressed in two types of developmentally defective root nodules elicited by Rhizobium meliloti. Fix- nodules were

  11. Effects of water stress on the rooting, nodulation potentials and ...

    African Journals Online (AJOL)

    Rooting, nodulation and growth ability of cowpea growing under limited water supply was investigated at the Teaching and Research Farm of the Imo State University, Owerri, Nigeria. The experiment was conducted in plastic buckets arranged in a completely Randomized Design with three replications, and treatments ...

  12. Root-nodule bacteria isolated from native Amphithalea ericifolia and ...

    African Journals Online (AJOL)

    Indigenous root-nodule bacteria isolated from the acid sands of the Cape using Aspalathus linearis, Aspalathus hispida, Aspalathus carnosa, Aspalathus capensis and Amphithalea ericifolia as trap hosts showed considerable tolerance to low pH. Isolates from A. ericifolia and A. carnosa could even grow in YMB medium at ...

  13. In situ localization of chalcone synthase mRNA in pea root nodule development.

    NARCIS (Netherlands)

    Yang, W.C.; Canter Cremers, H.C.J.; Hogendijk, P.; Katinakis, P.; Wijffelman, C.A.; Franssen, H.J.; Kammen, van A.; Bisseling, T.

    1992-01-01

    In this paper studies on the role of flavonoids in pea root nodule development are reported. Flavonoid synthesis was followed by localizing chalcone synthase (CHS) mRNA in infected pea roots and in root nodules. In a nodule primordium, CHS mRNA is present in all cells of the primordium. Therefore it

  14. Root nodule symbiosis in Lotus japonicus drives the establishment of distinctive rhizosphere, root, and nodule bacterial communities

    Science.gov (United States)

    Zgadzaj, Rafal; Garrido-Oter, Ruben; Jensen, Dorthe Bodker; Koprivova, Anna; Schulze-Lefert, Paul; Radutoiu, Simona

    2016-01-01

    Lotus japonicus has been used for decades as a model legume to study the establishment of binary symbiotic relationships with nitrogen-fixing rhizobia that trigger root nodule organogenesis for bacterial accommodation. Using community profiling of 16S rRNA gene amplicons, we reveal that in Lotus, distinctive nodule- and root-inhabiting communities are established by parallel, rather than consecutive, selection of bacteria from the rhizosphere and root compartments. Comparative analyses of wild-type (WT) and symbiotic mutants in Nod factor receptor5 (nfr5), Nodule inception (nin) and Lotus histidine kinase1 (lhk1) genes identified a previously unsuspected role of the nodulation pathway in the establishment of different bacterial assemblages in the root and rhizosphere. We found that the loss of nitrogen-fixing symbiosis dramatically alters community structure in the latter two compartments, affecting at least 14 bacterial orders. The differential plant growth phenotypes seen between WT and the symbiotic mutants in nonsupplemented soil were retained under nitrogen-supplemented conditions that blocked the formation of functional nodules in WT, whereas the symbiosis-impaired mutants maintain an altered community structure in the nitrogen-supplemented soil. This finding provides strong evidence that the root-associated community shift in the symbiotic mutants is a direct consequence of the disabled symbiosis pathway rather than an indirect effect resulting from abolished symbiotic nitrogen fixation. Our findings imply a role of the legume host in selecting a broad taxonomic range of root-associated bacteria that, in addition to rhizobia, likely contribute to plant growth and ecological performance. PMID:27864511

  15. Anatomy and ultrastructure of root nodules of Lupinus luteus

    Directory of Open Access Journals (Sweden)

    A. Woźny

    2015-01-01

    Full Text Available The paper presents anatomic structure of root nodules of lupine (Lupinus luteus L. cv. Express and ultrastructure of cells infected by Rhizobium, The inside of cells from the infected nodule region was filled with numerous bacteria; only centrally located cell nucleus was free of bacteria. Rhizobium was present mostly in the form of "transforming bacteria" (according to the terminology by Ching et al. 1977, characterized by visible nucleoid areas, numerous ribosomes, and polyphosphate granules, although typical bacterioids with poly-β-hydroxybutyrate were also found.

  16. Drought stress responses in soybean roots and nodules

    Directory of Open Access Journals (Sweden)

    Karl Kunert

    2016-07-01

    Full Text Available Drought is considered to be a major threat to soybean production worldwide and yet our current understanding of the effects of drought on soybean productively is largely based on studies on above-ground traits. Although the roots and root nodules are important sensors of drought, the responses of these crucial organs and their drought tolerance features remain poorly characterized. The symbiotic interaction between soybean and rhizobia facilitates atmospheric nitrogen fixation, a process that provides essential nitrogen to support plant growth and development. Symbiotic nitrogen fixation is important for sustainable agriculture, as it sustains plant growth on nitrogen-poor soils and limits fertilizer use for crop nitrogen nutrition. Recent developments have been made in our understanding of the drought impact on soybean root architecture and nodule traits, as well as underpinning transcriptome, proteome and also emerging metabolome information, with a view to improve the selection of more drought-tolerant soybean cultivars and rhizobia in the future. We conclude that the direct screening of root and nodule traits in the field as well as identification of genes, proteins and also metabolites involved in such traits will be essential in order to gain a better understanding of the regulation of root architecture, bacteroid development and lifespan in relation to drought tolerance in soybean.

  17. Drought Stress Responses in Soybean Roots and Nodules.

    Science.gov (United States)

    Kunert, Karl J; Vorster, Barend J; Fenta, Berhanu A; Kibido, Tsholofelo; Dionisio, Giuseppe; Foyer, Christine H

    2016-01-01

    Drought is considered to be a major threat to soybean production worldwide and yet our current understanding of the effects of drought on soybean productively is largely based on studies on above-ground traits. Although the roots and root nodules are important sensors of drought, the responses of these crucial organs and their drought tolerance features remain poorly characterized. The symbiotic interaction between soybean and rhizobia facilitates atmospheric nitrogen fixation, a process that provides essential nitrogen to support plant growth and development. Symbiotic nitrogen fixation is important for sustainable agriculture, as it sustains plant growth on nitrogen-poor soils and limits fertilizer use for crop nitrogen nutrition. Recent developments have been made in our understanding of the drought impact on soybean root architecture and nodule traits, as well as underpinning transcriptome, proteome and also emerging metabolome information, with a view to improve the selection of more drought-tolerant soybean cultivars and rhizobia in the future. We conclude that the direct screening of root and nodule traits in the field as well as identification of genes, proteins and also metabolites involved in such traits will be essential in order to gain a better understanding of the regulation of root architecture, bacteroid development and lifespan in relation to drought tolerance in soybean.

  18. Study of phenanthrene utilizing bacterial consortia associated with cowpea (Vigna unguiculata) root nodules.

    Science.gov (United States)

    Sun, Ran; Crowley, David E; Wei, Gehong

    2015-02-01

    Many legumes have been selected as model plants to degrade organic contaminants with their special associated rhizosphere microbes in soil. However, the function of root nodules during microbe-assisted phytoremediation is not clear. A pot study was conducted to examine phenanthrene (PHE) utilizing bacteria associated with root nodules and the effects of cowpea root nodules on phytoremediation in two different types of soils (freshly contaminated soil and aged contaminated soil). Cowpea nodules in freshly-contaminated soil showed less damage in comparison to the aged-contaminated soil, both morphologically and ultra-structurally by scanning electron microscopy. The study of polycyclic aromatic hydrocarbon (PAH) attenuation conducted by high performance liquid chromatography revealed that more PAH was eliminated from liquid culture around nodulated roots than nodule-free roots. PAH sublimation and denaturation gradient gel electrophoresis were applied to analyze the capability and diversity of PAH degrading bacteria from the following four parts of rhizo-microzone: bulk soil, root surface, nodule surface and nodule inside. The results indicated that the surface and inside of cowpea root nodules were colonized with bacterial consortia that utilized PHE. Our results demonstrated that root nodules not only fixed nitrogen, but also enriched PAH-utilizing microorganisms both inside and outside of the nodules. Legume nodules may have biotechnological values for PAH degradation.

  19. Nonphotosynthetic CO2 fixation by alfalfa (Medicago sativa L.) roots and nodules

    International Nuclear Information System (INIS)

    Anderson, M.P.; Heichel, G.H.; Vance, C.P.

    1987-01-01

    The dependence of alfalfa (Medicago sativa L.) root and nodule nonphotosynthetic CO 2 fixation on the supply of currently produced photosynthate and nodule nitrogenase activity was examined a various times after phloem-girdling and exposure of nodules to Ar:O 2 . Phloem-girdling was effected 20 hours and exposure to Ar:O 2 was effected 2 to 3 hours before initiation of experiments. Nodule and root CO 2 fixation rates of phloem-girdled plants were reduced to 38 and 50%, respectively, of those of control plants. Exposure to Ar:O 2 decreased nodule CO 2 fixation rates to 45%, respiration rates to 55%, and nitrogenase activities to 51% of those of the controls. The products of nodule CO 2 fixation were exported through the xylem to the shoot mainly as amino acids within 30 to 60 minutes after exposure to 14 CO 2 . In contrast to nodules, roots exported very little radioactivity, and most of the 14 C was exported as organic acids. The nonphotosynthetic CO 2 fixation rate of roots and nodules averaged 26% of the gross respiration rate, i.e. the sum of net respiration and nonphotosynthetic CO 2 assimilation. Nodules fixed CO 2 at a rate 5.6 times that of roots, but since nodules comprised a small portion of root system mass, roots accounted for 76% of the nodulated roots system CO 2 fixation. The results indicate that nodule CO 2 fixation in alfalfa is associated with N assimilation

  20. Root nodule symbiosis in Lotus japonicus drives the establishment of distinctive rhizosphere, root, and nodule bacterial communities

    OpenAIRE

    Zgadzaj, Rafal; Garrido-Oter, Ruben; Jensen, Dorthe Bodker; Koprivova, Anna; Schulze-Lefert, Paul; Radutoiu, Simona

    2016-01-01

    Legumes are known as pioneer plants colonizing marginal soils, and as enhancers of the nutritional status in cultivated soils. This beneficial activity has been explained by their capacity to engage in symbiotic relationship with nitrogen-fixing rhizobia. We performed a community profiling analysis of Lotus japonicus wild type and mutants to investigate the role of the nodulation pathway on the structure of the root-associated bacterial microbiota. We found that several bacterial orders were ...

  1. Occurrence and succession of mycorrhizas in Alnus incana

    Energy Technology Data Exchange (ETDEWEB)

    Arveby, A.S. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Section of Forest Ecophysiology; Granhall, U. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Microbiology

    1998-12-31

    The occurrence of different mycorrhizas of the grey alder, Alnus incana (L.) Moench., in Sweden was investigated. Root sampling was carried out in planted and natural grey alder stands, representing different soil types, geographical sites, and plant ages. Mycorrhizal infection of roots was found to be frequent at all investigated sites, except for some planted peat bogs, where alders do not occur naturally. At the latter sites, mycorrhizal infection was less frequent and consisted only of ectomycorrhizas. Young trees here were non-mycorrhizal. At all other sites vesicular-arbuscular mycorrhiza (VAM) was found to be the almost exclusive type of mycorrhiza in first-year seedlings. In trees older than one year ectomycorrhiza was the dominating type. In the planted stands up to five years of age no fruitbodies of ectomycorrhizal fungi were found. In such stands the ectomycorrhizas generally had thin, translucent mantles and could be observed only by microscopic examination. In one old plantation (27 years) and in the natural stands sporocarps of several specific `alder fungi` were found. Here, the mycorrhizal root tips had thick, mostly whitish mantles. The Hartig net was in all cases confined to penetration between epidermal cells. Soil collected from one alder site and two non-alder biotopes readily infected grey alder seedlings with Frankia and VAM fungi whereas a peat soil failed to infect seedlings with any symbiont. In vitro inoculation of nodulated seedlings with Glomus mossae (Nicol. and Gerd.) Gerdemann and Trappe resulted in VAM-infection. Simultaneous syntheses with isolates of alder-specific, and other, ectomycorrhizal fungi, using three different methods, failed. On the basis of these results an endomycorrhizal-ectomycorrhizal succession after the first growth season in Alnus incana is concluded. A subsequent succession of ectomycorrhizal species from early-stage to late-stage ones is discussed 58 refs, 3 figs, 2 tabs

  2. Effect of localized nitrogen availability to soybean half-root systems on photosynthate partitioning to roots and nodules

    International Nuclear Information System (INIS)

    Singleton, P.W.; van Kessel, C.

    1987-01-01

    Soybean (Glycine max [L.] Merr. cv Davis) was grown in a split-root growth system designed to maintain control of the root atmosphere. Two experiments were conducted to examine how 80% Ar:20%, O 2 (Ar:O 2 ) and air (Air) atmospheres affected N assimilation (NH 4 NO 3 and N 2 fixation) and the partitioning of photosynthate to roots and nodules. Application of NH 4 NO 3 to nonnodulated half-root systems enhanced root growth and root respiration at the site of application. A second experiment applied Ar:O 2 or air to the two sides of nodulated soybean half-root systems for 11 days in the following combinations: (a) Air to both sides (Air/Air); (b) Air to one side, Ar:O 2 to the other (Air/Ar:O 2 ), and (c) Ar:O 2 to both sides (Ar:O 2 /Ar:O 2 ). Results indicated that dry matter and current photosynthate ( 14 C) were selectively partitioned to nodules and roots where N 2 was available. Both root and nodule growth on the Air side of Air/Ar:O 2 plants was significantly greater than the Ar:O 2 side. The relative partitioning of carbon and current photosynthate between roots and nodules on a half-root system was also affected by N 2 availability. The Ar:O 2 sides partitioned relatively more current photosynthate to roots (57%) than nodules (43%), while N 2 -fixing root systems partitioned 36 and 64% of the carbon to roots and nodules, respectively. The Ar:O 2 atmosphere decreased root and nodule respiration by 80% and nitrogenase activity by 85% compared to half-root systems in Air while specific nitrogenase activity in Ar:O 2 was 50% of nodules supplied Air. Results indicated that nitrogen assimilation, whether from N 2 fixation or inorganic sources, had a localized effect on root development

  3. Rhizobium pongamiae sp. nov. from root nodules of Pongamia pinnata.

    Science.gov (United States)

    Kesari, Vigya; Ramesh, Aadi Moolam; Rangan, Latha

    2013-01-01

    Pongamia pinnata has an added advantage of N2-fixing ability and tolerance to stress conditions as compared with other biodiesel crops. It harbours "rhizobia" as an endophytic bacterial community on its root nodules. A gram-negative, nonmotile, fast-growing, rod-shaped, bacterial strain VKLR-01(T) was isolated from root nodules of Pongamia that grew optimal at 28°C, pH 7.0 in presence of 2% NaCl. Isolate VKLR-01 exhibits higher tolerance to the prevailing adverse conditions, for example, salt stress, elevated temperatures and alkalinity. Strain VKLR-01(T) has the major cellular fatty acid as C(18:1) ω7c (65.92%). Strain VKLR-01(T) was found to be a nitrogen fixer using the acetylene reduction assay and PCR detection of a nifH gene. On the basis of phenotypic, phylogenetic distinctiveness and molecular data (16S rRNA, recA, and atpD gene sequences, G + C content, DNA-DNA hybridization etc.), strain VKLR-01(T) = (MTCC 10513(T) = MSCL 1015(T)) is considered to represent a novel species of the genus Rhizobium for which the name Rhizobium pongamiae sp. nov. is proposed. Rhizobium pongamiae may possess specific traits that can be transferred to other rhizobia through biotechnological tools and can be directly used as inoculants for reclamation of wasteland; hence, they are very important from both economic and environmental prospects.

  4. Effect of Nitrate on Nodule and Root Growth of Soybean (Glycine max (L. Merr.

    Directory of Open Access Journals (Sweden)

    Akinori Saito

    2014-03-01

    Full Text Available The application of combined nitrogen, especially nitrate, to soybean plants is known to strongly inhibit nodule formation, growth and nitrogen fixation. In the present study, we measured the effects of supplying 5 mM nitrate on the growth of nodules, primary root, and lateral roots under light at 28 °C or dark at 18 °C conditions. Photographs of the nodulated roots were periodically taken by a digital camera at 1-h intervals, and the size of the nodules was measured with newly developed computer software. Nodule growth was depressed approximately 7 h after the addition of nitrate under light conditions. The nodule growth rate under dark conditions was almost half that under light conditions, and nodule growth was further suppressed by the addition of 5 mM nitrate. Similar results were observed for the extending growth rate of the primary root as those for nodule growth supplied with 5 mM nitrate under light/dark conditions. In contrast, the growth of lateral roots was promoted by the addition of 5 mM nitrate. The 2D-PAGE profiles of nodule protein showed similar patterns between the 0 and 5 mM nitrate treatments, which suggested that metabolic integrity may be maintained with the 5 mM nitrate treatment. Further studies are required to confirm whether light or temperature condition may give the primary effect on the growth of nodules and roots.

  5. Study of root para-nodules formation in wheat (Triticum durum ...

    African Journals Online (AJOL)

    djemel

    2013-08-28

    Aug 28, 2013 ... a growth chamber with hydroponic medium. Binocular observation revealed that para-nodules were formed when wheat roots were inoculated with Frankia and the root length was enhanced. When the inoculation with Frankia was combined to 2,4-D treatment, the para-nodules formed were bigger and.

  6. Genetic constraints that determine rhizobium-root nodule formation in Parasponia andersonii

    NARCIS (Netherlands)

    Seifi Kalhor, M.

    2016-01-01

    Bacteria of the genus Rhizobium play a very important role in agriculture by inducing nitrogen-fixing nodules on the roots of legumes. Root nodule symbiosis enables nitrogen‐fixing bacteria (Rhizobium) to convert atmospheric nitrogen into a form that is directly available for plant growth.

  7. Root and Nodulation Phenotypes of the Ethylene-Insensitive Sickle Mutant of Medicago truncatula

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    JOKO PRAYITNO

    2010-09-01

    Full Text Available The sickle (skl mutant of the model legume Medicago truncatula is an ethylene-sensitive mutant that have a ten-fold increase in nodule numbers. The nodulation and root phenotypes of the skl mutant were investigated and further characterised. The skl mutant had longer roots than the wild type, but when inoculated with Sinorhizobium, its root length was reduced to the level of wild type. Furthermore, lateral root numbers in uninoculated skl were similar to those in uninoculated wild type. However, when the root tips were decapitated, fewer lateral roots formed in skl than in wild type. Nodule numbers of the skl mutant were significantly reduced by low nitrate concentration (2.5 mM. These results suggest that skl mutant has alterations in both root and nodule development.

  8. Proteome reference maps of the Lotus japonicus nodule and root

    DEFF Research Database (Denmark)

    Dam, Svend Secher; Dyrlund, Thomas F.; Ussatjuk, Anna

    2014-01-01

    stress level at this developmental stage. In contrast, protein spots corresponding to nodulins such as leghemoglobin, asparagine synthetase, sucrose synthase, and glutamine synthetase were prevalent in red nodules. The distinct biochemical state of nodules was further highlighted by the conspicuous...

  9. Utilization of (15)NO3 (-) by nodulated soybean plants under conditions of root hypoxia.

    Science.gov (United States)

    Nunes Menolli Lanza, Luciana; Ferreira Lanza, Daniel Carlos; Sodek, Ladaslav

    2014-07-01

    Waterlogging of soils is common in nature. The low availability of oxygen under these conditions leads to hypoxia of the root system impairing the development and productivity of the plant. The presence of nitrate under flooding conditions is regarded as being beneficial towards tolerance to this stress. However, it is not known how nodulated soybean plants, cultivated in the absence of nitrate and therefore not metabolically adapted to this compound, would respond to nitrate under root hypoxia in comparison with non-nodulated plants grown on nitrate. A study was conducted with (15)N labelled nitrate supplied on waterlogging for a period of 48 h using both nodulated and non-nodulated plants of different physiological ages. Enrichment of N was found in roots and leaves with incorporation of the isotope in amino acids, although to a much smaller degree under hypoxia than normoxia. This demonstrates that nitrate is taken up under hypoxic conditions and assimilated into amino acids, although to a much lesser extent than for normoxia. The similar response obtained with nodulated and non-nodulated plants indicates the rapid metabolic adaptation of nodulated plants to the presence of nitrate under hypoxia. Enrichment of N in nodules was very much weaker with a distinct enrichment pattern of amino acids (especially asparagine) suggesting that labelling arose from a tissue source external to the nodule rather than through assimilation in the nodule itself.

  10. Production and Metabolism of Indole Acetic Acid in Root Nodules and Symbiont (Rhizobium undicola Isolated from Root Nodule of Aquatic Medicinal Legume Neptunia oleracea Lour.

    Directory of Open Access Journals (Sweden)

    Pallab Kumar Ghosh

    2015-01-01

    Full Text Available Indole acetic acid is a phytohormone which plays a vital role in plant growth and development. The purpose of this study was to shed some light on the production of IAA in roots, nodules, and symbionts of an aquatic legume Neptunia oleracea and its possible role in nodular symbiosis. The symbiont (N37 was isolated from nodules of this plant and identified as Rhizobium undicola based on biochemical characteristics, 16S rDNA sequence homology, and DNA-DNA hybridization results. The root nodules were found to contain more IAA and tryptophan than root; however, no detectable amount of IAA was found in root. The IAA metabolizing enzymes IAA oxidase, IAA peroxidase (E.C.1.11.1.7, and polyphenol oxidase (E.C.1.14.18.1 were higher in root than nodule but total phenol and IAA content were reversed. The strain N37 was found to produce copious amount of IAA in YEM broth medium with tryptophan and reached its stationary phase at 20 h. An enrichment of the medium with mannitol, ammonium sulphate, B12, and 4-hydroxybenzaldehyde was found to promote the IAA production. The presence of IAA metabolizing enzymes and IAA production with PGPR traits including ACC deaminase activity of the symbionts was essential for plant microbe interaction and nodule function.

  11. Identification of Ononitol and O-methyl-scyllo-inositol in Pea Root Nodules

    DEFF Research Database (Denmark)

    Skøt, Leif; Egsgaard, Helge

    1984-01-01

    Ononitol (4-O-methyl-myo-inositol) and O-methyl-scyllo-inositol were identified in pea (Pisum sativum L.) root nodules formed by twoRhizobium leguminosarum strains. Ononitol was the major soluble carbohydrate in nodules formed by strain 1045 while O-methyl-scyllo-inositol and two unidentified com...

  12. Comparison of the nodule vs. root transcriptome of the actinorhizal plant Datisca glomerata: actinorhizal nodules contain a specific class of defensins.

    Directory of Open Access Journals (Sweden)

    Irina V Demina

    Full Text Available Actinorhizal root nodule symbioses are very diverse, and the symbiosis of Datisca glomerata has previously been shown to have many unusual aspects. In order to gain molecular information on the infection mechanism, nodule development and nodule metabolism, we compared the transcriptomes of D. glomerata roots and nodules. Root and nodule libraries representing the 3'-ends of cDNAs were subjected to high-throughput parallel 454 sequencing. To identify the corresponding genes and to improve the assembly, Illumina sequencing of the nodule transcriptome was performed as well. The evaluation revealed 406 differentially regulated genes, 295 of which (72.7% could be assigned a function based on homology. Analysis of the nodule transcriptome showed that genes encoding components of the common symbiosis signaling pathway were present in nodules of D. glomerata, which in combination with the previously established function of SymRK in D. glomerata nodulation suggests that this pathway is also active in actinorhizal Cucurbitales. Furthermore, comparison of the D. glomerata nodule transcriptome with nodule transcriptomes from actinorhizal Fagales revealed a new subgroup of nodule-specific defensins that might play a role specific to actinorhizal symbioses. The D. glomerata members of this defensin subgroup contain an acidic C-terminal domain that was never found in plant defensins before.

  13. Role of mungbean root nodule associated fluorescent Pseudomonas and rhizobia in suppressing the root rotting fungi and root knot nematodes in chickpea (Cicer arietinum L.)

    International Nuclear Information System (INIS)

    Noreen, R.; Shafique, A.; Haque, S.E.; Ali, S.A.

    2016-01-01

    Three isolates each of fluorescent Pseudomonas (NAFP-19, NAFP-31 and NAFP-32) and rhizobia (NFB- 103, NFB-107 and NFB-109) which were originally isolated from root nodules of mungbean (Vigna radiata) showed significant biocontrol activity in the screen house and under field condition, against root rotting fungi viz., Macrophomina phaseolina, Fusarium solani, F. oxysporum and Rhizoctonia solani evaluated on chickpea. Biocontrol potential of these isolates was also evaluated against Meloidogyne incognita, the root knot nematode. Application of Pseudomonas and rhizobial isolates as a soil drench, separately or mixed significantly reduced root rot disease under screen house and field conditions. Nematode penetration in roots was also found significantly less in rhizobia or Pseudomonas treatments used separately or mixed as compared to control. Fluorescent Pseudomonas treated plants produced greater number of nodules per plant than control plants and about equal to rhizobia treated plants, indicating that root nodule associated fluorescent Pseudomonas enhance root nodulation. (author)

  14. Root hair deformation activity of nodulation factor and their fate on Vicia sativa.

    NARCIS (Netherlands)

    Heidstra, R.; Geurts, R.; Franssen, H.; Spaink, H.P.; Kammen, van A.; Bisseling, T.

    1994-01-01

    We used a semiquantitative root hair deformation assay for Vicia sativa (vetch) to study the activity of Rhizobium leguminosarum bv viciae nodulation (Nod) factors. Five to 10 min of Nod factor-root interaction appears to be sufficient to induce root hair deformation. The first deformation is

  15. Metabolic responses in root nodules of Phaseolus vulgaris and Vicia sativa exposed to the imazamox herbicide.

    Science.gov (United States)

    García-Garijo, A; Tejera, N A; Lluch, C; Palma, F

    2014-05-01

    Alterations on growth, amino acids metabolism and some antioxidant enzyme activities as result of imazamox treatment were examined in determinate and indeterminate nodules, formed by Phaseolus vulgaris and Vicia sativa, respectively. Young seedlings of both legumes were inoculated with their respective microsymbionts and grown under controlled conditions. At vegetative growth, plants were treated with imazamox (250μM) in the nutrient solution and harvested 7days after. Imazamox was mainly accumulated in V. sativa where concentrations were more than six fold higher than those detected in P. vulgaris. Nodule dry weight and total nitrogen content were reduced by the herbicide treatment: the highest decrease of nodule biomass (50%) and nitrogen content (40%) were registered in V. sativa and P. vulgaris, respectively. The concentration of branched-chain amino acids (BCAA) did not change in neither determinate nor indeterminate nodules even though the acetohydroxyacid synthase activity decreased in root and nodules of both symbioses with the herbicide application. Based on this last result and taking into account that total free amino acids increased in roots but not in nodules of common vetch, a possible BCAA translocation from root to nodule could occur. Our results suggest that the maintenance of BCAA balance in nodule become a priority for the plant in such conditions. The involvement of activities glutathione-S-transferase, guaiacol peroxidase and superoxide dismutase in the response of the symbioses to imazamox are also discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Leguminous plants: inventors of root nodules to accommodate symbiotic bacteria.

    Science.gov (United States)

    Suzaki, Takuya; Yoro, Emiko; Kawaguchi, Masayoshi

    2015-01-01

    Legumes and a few other plant species can establish a symbiotic relationship with nitrogen-fixing rhizobia, which enables them to survive in a nitrogen-deficient environment. During the course of nodulation, infection with rhizobia induces the dedifferentiation of host cells to form primordia of a symbiotic organ, the nodule, which prepares plants to accommodate rhizobia in host cells. While these nodulation processes are known to be genetically controlled by both plants and rhizobia, recent advances in studies on two model legumes, Lotus japonicus and Medicago truncatula, have provided great insight into the underlying plant-side molecular mechanism. In this chapter, we review such knowledge, with particular emphasis on two key processes of nodulation, nodule development and rhizobial invasion. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Waterlogging-induced changes in fermentative metabolism in roots and nodules of soybean genotypes

    Directory of Open Access Journals (Sweden)

    Junior Borella

    2014-12-01

    Full Text Available Waterlogging blocks the oxygen supply to the root system which inhibits respiration, and greatly reduces the energy status of cells that affect important metabolic processes. This study evaluated fermentative metabolism and carbohydrate contents in the root system of two soybean (Glycine max L. Merril genotypes under hypoxic and post-hypoxic conditions. Nodulated plants (genotypes Fundacep 53 RR and BRS Macota were grown in vermiculite and transferred to a hydroponic system at the reproductive stage. The root system was submitted to hypoxia by flowing N2 (nitrogen gas in a solution for 24 and 72 h. For recovery, plants returned to normoxia condition by transfer to vermiculite for 24 and 72 h. Fermentative enzyme activity, levels of anaerobic metabolites and carbohydrate content were all quantified in roots and nodules. The activity of alcohol dehydrogenase, pyruvate decarboxylase and lactate dehydrogenase enzymes, as well as the content of ethanol and lactate, increased with hypoxia in roots and nodules, and subsequently returned to pre-hypoxic levels in the recovery phase in both genotypes. Pyruvate content increased in nodules and decreased in roots. Sugar and sucrose levels increased in roots and decreased in nodules under hypoxia in both genotypes. Fundacep RR 53 was more responsive to the metabolic effects caused by hypoxia and post-hypoxia than BRS Macota, and it is likely that these characteristics contribute positively to improving adaptation to oxygen deficiency.

  18. Infection and invasion of roots by symbiotic, nitrogen-fixing rhizobia during nodulation of temperate legumes.

    Science.gov (United States)

    Gage, Daniel J

    2004-06-01

    Bacteria belonging to the genera Rhizobium, Mesorhizobium, Sinorhizobium, Bradyrhizobium, and Azorhizobium (collectively referred to as rhizobia) grow in the soil as free-living organisms but can also live as nitrogen-fixing symbionts inside root nodule cells of legume plants. The interactions between several rhizobial species and their host plants have become models for this type of nitrogen-fixing symbiosis. Temperate legumes such as alfalfa, pea, and vetch form indeterminate nodules that arise from root inner and middle cortical cells and grow out from the root via a persistent meristem. During the formation of functional indeterminate nodules, symbiotic bacteria must gain access to the interior of the host root. To get from the outside to the inside, rhizobia grow and divide in tubules called infection threads, which are composite structures derived from the two symbiotic partners. This review focuses on symbiotic infection and invasion during the formation of indeterminate nodules. It summarizes root hair growth, how root hair growth is influenced by rhizobial signaling molecules, infection of root hairs, infection thread extension down root hairs, infection thread growth into root tissue, and the plant and bacterial contributions necessary for infection thread formation and growth. The review also summarizes recent advances concerning the growth dynamics of rhizobial populations in infection threads.

  19. Transport and partitioning of CO2 fixed by root nodules of ureide and amide producing legumes

    International Nuclear Information System (INIS)

    Vance, C.P.; Boylan, K.L.M.; Maxwell, C.A.; Heichel, G.H.; Hardman, L.L.

    1985-01-01

    Nodulated and denodulated roots of adzuki bean (Vigna angularis), soybean (Glycine max), and alfalfa (Medicago sativa) were exposed to 14 CO 2 to investigate the contribution of nodule CO 2 fixation to assimilation and transport of fixed nitrogen. The distribution of radioactivity in xylem sap and partitioning of carbon fixed by nodules to the whole plant were measured. Radioactivity in the xylem sap of nodulated soybean and adzuki bean was located primarily (70 to 87%) in the acid fraction while the basic (amino acid) fraction contained 10 to 22%. In contrast radioactivity in the xylem sap of nodulated alfalfa was primarily in amino acids with about 20% in organic acids. Total ureide concentration was 8.1, 4.7, and 0.0 micromoles per milliliter xylem sap for soybean, adzuki bean, and alfalfa, respectively. While the major nitrogen transport products in soybeans and adzuki beans are ureides, this class of metabolites contained less than 20% of the the total radioactivity. When nodules of plants were removed, radioactivity in xylem sap decreased by 90% or more. Pulse-chase experiments indicated that CO 2 fixed by nodules was rapidly transported to shoots and incorporated into acid stable constituents. The data are consistent with a role for nodule CO 2 fixation providing carbon for the assimilation and transport of fixed nitrogen in amide-based legumes. In contrast, CO 2 fixation by nodules of ureide transporting legumes appears to contribute little to assimilation and transport of fixed nitrogen. 19 references, 2 figures, 5 tables

  20. Endophytic and epiphytic hydrocarbon-utilizing bacteria associated with root nodules of legumes

    International Nuclear Information System (INIS)

    Dashti, N.; Khanafer, M.; Radwan, S.S.

    2005-01-01

    During their withdrawal from Kuwait in 1991, the Iraqi forces damaged and set fire to approximately 700 oil wells. Oil gushed from the wells for a period of 7 months, resulting in oil lakes which covered about 50 square km of the Kuwaiti desert and posing an environmental problem. Most of the crude oil has been pumped out, leaving the lake bottoms polluted with oil to depths reaching 20 to 25 cm. The oily areas have been mediated through indigenous hydrocarbon-utilizing microorganisms, but recovery is slow. Rhizospheres of crop plants, including legumes, are rich in oil-utilizing bacteria. Cultivation of broad beans in oily desert samples has enhanced oil biodegradation. This paper discussed the evidence that rhizobium strains inside the nodules on roots of broad beans are active in hydrocarbon utilization, and that the nodules are also colonized on their entire surfaces with oil-utilizing bacteria. Nodule-associated hydrocarbon utilizers appear to contribute together with rhizospheric hydrocarbon utilizers to the phytoremediation of oily soil. Broad beans were removed from soil and their root surfaces were sterilized to eliminate rhizospheric microorganisms. Plants with intact nodules were tested for their potential of attenuating to crude oil in water. Plants were divided into 2 groups: control plants in which all nodules were removed; and experimental plants which were used directly without further treatment. To isolate rhizobium from inside the nodules, fresh nodules were washed, sterilized and homogenized in sterile water. Bacterial strains were tested for their hydrocarbon utilization potential by streaking cell suspensions on the surface of sterile inorganic mediums containing 1 per cent of crude oil or of individual pure aliphatic and aromatic test hydrocarbons. All bacterial isolates were tested for growth on a solid Ashbery's nitrogen free medium. Results indicated that hydrocarbons were more efficiently eliminated from water supporting disinfected

  1. Phenolphthalein false-positive reactions from legume root nodules.

    Science.gov (United States)

    Petersen, Daniel; Kovacs, Frank

    2014-03-01

    Presumptive tests for blood play a critical role in the examination of physical evidence and in the determination of subsequent analysis. The catalytic power of hemoglobin allows colorimetric reactions employing phenolphthalein (Kastle-Meyer test) to indicate "whether" blood is present. Consequently, DNA profiles extracted from phenolphthalein-positive stains are presumed to be from blood on the evidentiary item and can lead to the identification of "whose" blood is present. Crushed nodules from a variety of legumes yielded phenolphthalein false-positive reactions that were indistinguishable from true bloodstains both in color quality and in developmental time frame. Clothing and other materials stained by nodules also yielded phenolphthalein false-positive reactivity for several years after nodule exposure. Nodules from leguminous plants contain a protein (leghemoglobin) which is structurally and functionally similar to hemoglobin. Testing of purified leghemoglobin confirmed this protein as a source of phenolphthalein reactivity. A scenario is presented showing how the presence of leghemoglobin from nodule staining can mislead investigators. © 2013 American Academy of Forensic Sciences.

  2. Infection and Invasion of Roots by Symbiotic, Nitrogen-Fixing Rhizobia during Nodulation of Temperate Legumes

    OpenAIRE

    Gage, Daniel J.

    2004-01-01

    Bacteria belonging to the genera Rhizobium, Mesorhizobium, Sinorhizobium, Bradyrhizobium, and Azorhizobium (collectively referred to as rhizobia) grow in the soil as free-living organisms but can also live as nitrogen-fixing symbionts inside root nodule cells of legume plants. The interactions between several rhizobial species and their host plants have become models for this type of nitrogen-fixing symbiosis. Temperate legumes such as alfalfa, pea, and vetch form indeterminate nodules that a...

  3. Morphogenesis of root nodules in white clover. II. The effect of mutation in genes nod IJ of the microsymbiont upon the nodule structure

    Directory of Open Access Journals (Sweden)

    Barbara Łotocka

    2014-01-01

    Full Text Available Morphogenesis of ineffective root nodules initiated on the roots of white clover 'Astra' by the Rhizobium leguminosarum biovar. trifolii strains ANU261 (Tn5 insertion in nod 1 gene and ANU262 (Tn5 insertion in nod J gene was investigated. Following changes were observed, as compared to the wild-type nodulation: the exaggerated, not delayed reaction of root hairs; the delay in nodulation with the number of nodules the same as in plants inoculated with a wild strain; the formation and organization of the nodule primordium not changed in comparison with the wild-type nodules; infection threads abnormally branched and diffusing with bacteria deprived of light zone and enriched with storage material; infected cells of bacteroidal tissue abnormally strongly osmiophilic and only slightly vacuolated; symbiosomes with very narrowed peribacteroidal space, subject to premature degradation; abnormal accumulation of starch in the nodule tissues; nodule development blocked at the stage of laterally situated meristem and single nodule bundle; inhibition of divisions in the meristem and vacuolation of its cells; the appearance of single cells with colonies of saprophytic rhizobia embedded in the fibrillar matrix in the old, degraded regions of the bacteroidal tissue.

  4. CO2 fixation in alfalfa and birdsfoot trefoil root nodules and partitioning of 14C to the plant

    International Nuclear Information System (INIS)

    Maxwell, C.A.; Vance, C.P.; Heichel, G.H.; Stade, S.

    1984-01-01

    The objectives of this study were to determine if nonphotosynthetic CO 2 fixation by root nodules contributes carbon for the assimilation of fixed N 2 in alfalfa (Medicago sativa L.) and birdsfoot trefoil (Lotus corniculatus L.) and if assimilation products are partitioned to different plant organs. Effective alfalfa nodules excised from or attached to roots had apparent 14 CO 2 fixation rates of 50 to 80 μg CO 2 kg -1 s -1 (dry weight) at 0.0012 to 0.0038 mole fraction CO 2 . Nodule CO 2 fixation rates increased six- to seven-fold as ambient CO 2 was raised from 0.0038 to 0.0663 mole fraction. Respiration rates of nodules (3 to 4 mg CO 2 kg -1 s -1 ) were 10 to 100-fold higher than 14 CO 2 fixation rates of nodules. Pulse chase experiments with 14 CO 2 combined with nodule and xylem sap analysis demonstrated the initial products of root and nodule CO 2 fixation were organic acids. However, the export of fixed 14 C from effective nodules was primarily in the form of amino acids. In contrast, nodule and/or root fixed 14 C in ineffectively nodulated alfalfa and denodulated effective alfalfa and birdsfoot trefoil was transported primarily as organic acids. Aspartate, asparagine, alanine, glutamate, and glutamine were the most heavily labeled compounds in the amino acid fraction of both effective alfalfa and birdsfoot trefoil nodules exposed to 14 CO 2 . By contrast, asparate, asparagine, and glutamine were the predominantly labeled amino acids in xylem sap collected from nodulated effective roots exposed to 14 CO 2 . The occurrence of nodule CO 2 fixation in alfalfa and birdsfoot trefoil and the export of fixed carbon as asparagine and aspartate to roots and shoots is consistent with a role for CO 2 fixation by nodules in providing carbon skeletons for assimilation and transport of symbiotically fixed N 2

  5. Nitrogen transfer in the interface between the symbionts in pea root nodules

    DEFF Research Database (Denmark)

    Rosendahl, L.; Mouritzen, P.; Rudbeck, A.

    2001-01-01

    Transport mechanisms for transfer of nitrogen from the bacteroid side across the symbiosome membrane of pea (Pisum sativum L.) root nodules were identified by the use of energised bacteroid side-out symbiosome membrane vesicles. Such membrane vesicles were used to study a mechanism with high...... was not observed. The ammonium transporter has been identified as a voltage-driven channel whereas the symbiosome membrane aspartate transporter appears to be a H+/aspartate symport. The results suggest that nitrogen transfer between the symbionts in pea root nodules involves transfer of amino acids as well...

  6. Antioxidant defenses in the peripheral cell layers of legume root nodules.

    Science.gov (United States)

    Dalton, D A; Joyner, S L; Becana, M; Iturbe-Ormaetxe, I; Chatfield, J M

    1998-01-01

    Ascorbate peroxidase (AP) is a key enzyme that scavenges potentially harmful H2O2 and thus prevents oxidative damage in plants, especially in N2-fixing legume root nodules. The present study demonstrates that the nodule endodermis of alfalfa (Medicago sativa) root nodules contains elevated levels of AP protein, as well as the corresponding mRNA transcript and substrate (ascorbate). Enhanced AP protein levels were also found in cells immediately peripheral to the infected region of soybean (Glycine max), pea (Pisum sativum), clover (Trifolium pratense), and common bean (Phaseolus vulgaris) nodules. Regeneration of ascorbate was achieved by (homo)glutathione and associated enzymes of the ascorbate-glutathione pathway, which were present at high levels. The presence of high levels of antioxidants suggests that respiratory consumption of O2 in the endodermis or nodule parenchyma may be an essential component of the O2-diffusion barrier that regulates the entry of O2 into the central region of nodules and ensures optimal functioning of nitrogenase.

  7. Effects of lime and calcium on root development and nodulation of clovers

    Energy Technology Data Exchange (ETDEWEB)

    Brauer, D.; Ritchey, D.; Belesky, D. [USDA ARS, Booneville, AR (USA). SPA Dale Bumpers Small Farms Research Centre

    2002-07-01

    Acidic soils can reduce the nodulation of forage legumes. Studies with a Gilpin series silt loam (fine loamy, mixed mesic Typic Hapludult) from New, WV, USA were conducted to determine the effects of lime on root development, and to assess effects of soil Ca and pH on nodulation. Liming increased soil pH from 4.8 to 5.3, nodulation, and root growth of white clover (Trifolium repens L., cultivar Huia) 28 d after planting. Seedlings from unlimed soil formed fewer indeterminate and determinate roots. Next, soils were amended with either CaCO{sub 3} or a mixture of CaCO{sub 3} and CaSO{sub 4} to achieve a soil pH of 4.7 to 6.1 and soil Ca of 170 to 680 mg kg{sup -1} soil. There was a strong quadratic relationship between number of nodules per white clover seedling 28 d after planting and soil pH. Another experiment was conducted to determine if these trends were expressed under field conditions. In 1993, field plots were amended with lime or a coal combustion by-product that supplied Ca as CaSO{sub 4} and seeded in 1994 to cool-season grasses. In spring of 1998, plots were drilled with either red (Trifolium pratense, L.) or white clover. The nodules per primary root were determined in May (1998,1999) and August (1998). Number of nodules per primary root was more closely associated with soil pH than soil Ca.

  8. The MicroRNA390/TAS3 Pathway Mediates Symbiotic Nodulation and Lateral Root Growth1[OPEN

    Science.gov (United States)

    Bustos-Sanmamed, Pilar; Mysore, Kirankumar S.

    2017-01-01

    Legume roots form two types of postembryonic organs, lateral roots and symbiotic nodules. Nodule formation is the result of the interaction of legumes with rhizobia and requires the mitotic activation and differentiation of root cells as well as an independent, but coordinated, program that allows infection by rhizobia. MicroRNA390 (miR390) is an evolutionarily conserved microRNA that targets the Trans-Acting Short Interference RNA3 (TAS3) transcript. Cleavage of TAS3 by ARGONAUTE7 results in the production of trans-acting small interference RNAs, which target mRNAs encoding AUXIN RESPONSE FACTOR2 (ARF2), ARF3, and ARF4. Here, we show that activation of the miR390/TAS3 regulatory module by overexpression of miR390 in Medicago truncatula promotes lateral root growth but prevents nodule organogenesis, rhizobial infection, and the induction of two key nodulation genes, Nodulation Signaling Pathway1 (NSP1) and NSP2. Accordingly, inactivation of the miR390/TAS3 module, either by expression of a miR390 target mimicry construct or mutations in ARGONAUTE7, enhances nodulation and rhizobial infection, alters the spatial distribution of the nodules, and increases the percentage of nodules with multiple meristems. Our results revealed a key role of the miR390/TAS3 pathway in legumes as a modulator of lateral root organs, playing opposite roles in lateral root and nodule development. PMID:28663332

  9. Expression of a complete soybean leghemoglobin gene in root nodules of transgenic Lotus corniculatus

    DEFF Research Database (Denmark)

    Stougaard, J; Petersen, T E; Marcker, K A

    1987-01-01

    The complete soybean leghemoglobin lbc(3) gene was transferred into the legume Lotus corniculatus using an Agrobacterium rhizogenes vector system. Organ-specific expression of the soybean gene was observed in root nodules formed on regenerated transgenic plants after infection with Rhizobium loti...

  10. Nonlegumes, legumes, and root nodules harbor different arbuscular mycorrhizal fungal communities.

    NARCIS (Netherlands)

    Scheublin, T.R.; Ridgway, K.P.; Young, J.P.W.; van der Heijden, M.G.A.

    2004-01-01

    Legumes are an important plant functional group since they can form a tripartite symbiosis with nitrogen-fixing Rhizobium bacteria and phosphorus-acquiring arbuscular mycorrhizal fungi (AMF). However, not much is known about AMF community composition in legumes and their root nodules. In this study,

  11. [Effects of environmental stress on seedlings root growth and nodulation of leguminous shrubs in the dry valley of Minjiang River].

    Science.gov (United States)

    Li, Fang-Lan; Zhu, Lin-Hai; Bao, Wei-Kai

    2009-08-01

    A field investigation was made to understand the seedlings root nodulation, biomass accumulation, root length, and fine root percentage of Sophora davidii, Indigofera lenticellata and Campylotropis polyantha along an altitudinal gradient on two contrasting sloped hills (north Zongqu and south Jingzhoushan) in the dry valley of Minjiang River. In the meantime, a greenhouse experiment was conducted to study the adaptation responses of 2 month-old S. davidii and C. polyantha seedlings root nodulation to different soil moisture regimes (80%, 60%, 40%, and 20% WHC). For the three test shrub species, fewer nodules were observed at lower altitude (1600-1950 m) areas, the nodule number per plant of S. davidii, I. lenticellata, and C. polyantha being 0.1 +/- 0.1, 0.9 +/- 0.5, and 5.7 +/- 1.9, and the non-nodulation plant accounting for 65.1%, 12.3% and 17.6%, respectively. The nodule number of the three species increased with increasing altitude, and correlated positively with root length and fine root percentage. However, there were no significant differences in the plant growth and biomass at different altitudes. When the soil moisture content was lower than 60% WHC, the nodule number and the fresh and dry mass of both S. davidii and C. polyantha decreased markedly, and at 20% WHC, no nodule and only 9.8 +/- 3.6 nodules were observed for S. davidii and C. polyantha, respectively, indicating that in this dry valley, the root nodulation capability of endemic leguminous shrubs was very low. Comparing with S. davidii, C. polyantha had higher root nodulation capability and drought-resistance. Prior to introducing these shrub species in forestation practices, to keep the soil moisture content higher than 40% WHC was recommended for relatively efficient biological nitrogen fixation.

  12. Utilization of 15NO3− by nodulated soybean plants under conditions of root hypoxia

    OpenAIRE

    Nunes Menolli Lanza, Luciana; Ferreira Lanza, Daniel Carlos; Sodek, Ladaslav

    2014-01-01

    Waterlogging of soils is common in nature. The low availability of oxygen under these conditions leads to hypoxia of the root system impairing the development and productivity of the plant. The presence of nitrate under flooding conditions is regarded as being beneficial towards tolerance to this stress. However, it is not known how nodulated soybean plants, cultivated in the absence of nitrate and therefore not metabolically adapted to this compound, would respond to nitrate under root hypox...

  13. Diversity of root nodule bacteria from leguminous crops

    Directory of Open Access Journals (Sweden)

    Agrawal Pooja

    2016-01-01

    Full Text Available In the present study, a total of 353 nodule-associated bacteria were isolated from 220 legume plant samples belonging to Cicer arietinum (85, Glycine max (74, Vigna radiata (21 and Cajanus cajan (40. A total of 224 bacteria were identified as fast-growing Rhizobium spp. on the basis of differential staining (Gram staining and carbol fuchsin staining and biochemical tests. All the isolates were tested for indole acetic acid production (IAA, phosphate solubilization and siderophore production on plate assay. To examine the effect of volatile organic metabolites (VOM and water soluble soil components (WSSC on nodule bacteria, culture conditions were optimized by observing the effects of various parameters such as pH, salt content and temperatures on the growth of bacteria. Selected rhizobia were subjected to random amplified polymorphic DNA (RAPD and amplified ribosomal DNA restriction analysis (ARDRA analysis to identify their species. On the basis of RAPD and ARDRA, 10 isolates were identified as Rhizobium meliloti. In this study, Rhizobium GO4, G16, G20, G77, S43, S81, M07, M37, A15 and A55 were observed as the best candidates among the tested bacteria and can be further used as potent bioinoculants.

  14. Transcriptome Changes in Hirschfeldia incana in Response to Lead Exposure

    Science.gov (United States)

    Auguy, Florence; Fahr, Mouna; Moulin, Patricia; El Mzibri, Mohamed; Smouni, Abdelaziz; Filali-Maltouf, Abdelkarim; Béna, Gilles; Doumas, Patrick

    2016-01-01

    Hirschfeldia incana, a pseudometallophyte belonging to the Brassicaceae family and widespread in the Mediterranean region, was selected for its ability to grow on soils contaminated by lead (Pb). The global comparison of gene expression using microarrays between a plant susceptible to Pb (Arabidopsis thaliana) and a Pb tolerant plant (H. incana) enabled the identification of a set of specific genes expressed in response to lead exposure. Three groups of genes were particularly over-represented by the Pb exposure in the biological processes categorized as photosynthesis, cell wall, and metal handling. Each of these gene groups was shown to be directly involved in tolerance or in protection mechanisms to the phytotoxicity associated with Pb. Among these genes, we demonstrated that MT2b, a metallothionein gene, was involved in lead accumulation, confirming the important role of metallothioneins in the accumulation and the distribution of Pb in leaves. On the other hand, several genes involved in biosynthesis of ABA were shown to be up-regulated in the roots and shoots of H. incana treated with Pb, suggesting that ABA-mediated signaling is a possible mechanism in response to Pb treatment in H. incana. This latest finding is an important research direction for future studies. PMID:26793211

  15. Molecular diversity of legume root-nodule bacteria in Kakadu National Park, Northern Territory, Australia.

    Directory of Open Access Journals (Sweden)

    Bénédicte Lafay

    2007-03-01

    Full Text Available Symbiotic relationships between leguminous plants (family Fabaceae and nodule-forming bacteria in Australia native ecosystems remain poorly characterized despite their importance. Most studies have focused on temperate parts of the country, where the use of molecular approaches have already revealed the presence of Bradyrhizobium, Ensifer (formerly Sinorhizobium, Mesorhizobium and Rhizobium genera of legume root-nodule bacteria. We here provide the first molecular characterization of nodulating bacteria from tropical Australia.45 nodule-forming bacterial strains, isolated from eight native legume hosts at eight locations in Kakadu National Park, Northern Territory, Australia, were examined for their genetic diversity and phylogenetic position. Using SSU rDNA PCR-RFLPs and phylogenetic analyses, our survey identified nine genospecies, two of which, Bradyrhizobium genospp. B and P, had been previously identified in south-eastern Australia and one, Mesorhizobium genospecies AA, in southern France. Three of the five newly characterized Bradyrhizobium genospecies were more closely related to B. japonicum USDA110, whereas the other two belonged to the B. elkanii group. All five were each more closely related to strains sampled in various tropical areas outside Australia than to strains known to occur in Australia. We also characterized an entirely novel nodule-forming lineage, phylogenetically distant from any previously described rhizobial and non-rhizobial legume-nodulating lineage within the Rhizobiales.Overall, the present results support the hypothesis of tropical areas being centres of biodiversity and diversification for legume root-nodule bacteria and confirm the widespread occurrence of Bradyrhizobium genosp. B in continental Australia.

  16. effect of exogenous application of rhizopine on lucerne root nodulation

    African Journals Online (AJOL)

    BSN

    U1111·ersi1y of Adelaide, South Australia. *Corresspondaning author. AB TRACT. Rhizopine, 3-0 -methyl scyllo-inosamine was applied to the roots of luceme seedling inoculated with either rhizopine synthesizing Sinorhizobium meliloti strain L530 or the non-rhizopine synthesizing strain Rm 1021. There was an initial ...

  17. The relationship between thiamine and two symbioses: Root nodule symbiosis and arbuscular mycorrhiza.

    Science.gov (United States)

    Nagae, Miwa; Parniske, Martin; Kawaguchi, Masayoshi; Takeda, Naoya

    2016-12-01

    Lotus japonicus THIC is expressed in all organs, and the encoded protein catalyzes thiamine biosynthesis. Loss of function produces chlorosis, a typical thiamine-deficiency phenotype, and mortality. To investigate thiamine's role in symbiosis, we focused on THI1, a thiamine-biosynthesis gene expressed in roots, nodules, and seeds. The thi1 mutant had green leaves, but formed small nodules and immature seeds. These phenotypes were rescued by THI1 complementation and by exogenous thiamine. Thus, THI1 is required for nodule enlargement and seed maturation. On the other hand, colonization by arbuscular mycorrhiza (AM) fungus Rhizophagus irregularis was not affected in the thi1 mutant or by exogenous thiamine. However, spores of R. irregularis stored more thiamine than the source (host plants), despite lacking thiamine biosynthesis genes. Therefore, disturbance of the thiamine supply would affect progeny phenotypes such as spore formation and hyphal growth. Further investigation will be required to elucidate thiamine's effect on AM.

  18. Agrobacterium rhizogenes transformed soybean roots differ in their nodulation and nitrogen fixation response to genistein and salt stress.

    Science.gov (United States)

    Dolatabadian, Aria; Modarres Sanavy, Seyed Ali Mohammad; Ghanati, Faezeh; Gresshoff, Peter M

    2013-07-01

    We evaluated response differences of normal and transformed (so-called 'hairy') roots of soybean (Glycine max L. (Merr.), cv L17) to the Nod-factor inducing isoflavone genistein and salinity by quantifying growth, nodulation, nitrogen fixation and biochemical changes. Composite soybean plants were generated using Agrobacterium rhizogenes-mediated transformation of non-nodulating mutant nod139 (GmNFR5α minus) with complementing A. rhizogenes K599 carrying the wild-type GmNFR5α gene under control of the constitutive CaMV 35S promoter. We used genetic complementation for nodulation ability as only nodulated roots were scored. After hairy root emergence, primary roots were removed and composite plants were inoculated with Bradyrhizobium japonicum (strain CB1809) pre-induced with 10 μM genistein and watered with NaCl (0, 25, 50 and 100 mM). There were significant differences between hairy roots and natural roots in their responses to salt stress and genistein application. In addition, there were noticeable nodulation and nitrogen fixation differences. Composite plants had better growth, more root volume and chlorophyll as well as more nodules and higher nitrogenase activity (acetylene reduction) compared with natural roots. Decreased lipid peroxidation, proline accumulation and catalase/peroxidase activities were found in 'hairy' roots under salinity stress. Genistein significantly increased nodulation and nitrogen fixation and improved roots and shoot growth. Although genistein alleviated lipid peroxidation under salinity stress, it had no significant effect on the activity of antioxidant enzymes. In general, composite plants were more competitive in growth, nodulation and nitrogen fixation than normal non-transgenic even under salinity stress conditions.

  19. Metabolomic Profiling of Bradyrhizobium diazoefficiens-Induced Root Nodules Reveals Both Host Plant-Specific and Developmental Signatures

    Directory of Open Access Journals (Sweden)

    Martina Lardi

    2016-05-01

    Full Text Available Bradyrhizobium diazoefficiens is a nitrogen-fixing endosymbiont, which can grow inside root-nodule cells of the agriculturally important soybean and other host plants. Our previous studies described B. diazoefficiens host-specific global expression changes occurring during legume infection at the transcript and protein level. In order to further characterize nodule metabolism, we here determine by flow injection–time-of-flight mass spectrometry analysis the metabolome of (i nodules and roots from four different B. diazoefficiens host plants; (ii soybean nodules harvested at different time points during nodule development; and (iii soybean nodules infected by two strains mutated in key genes for nitrogen fixation, respectively. Ribose (soybean, tartaric acid (mungbean, hydroxybutanoyloxybutanoate (siratro and catechol (cowpea were among the metabolites found to be specifically elevated in one of the respective host plants. While the level of C4-dicarboxylic acids decreased during soybean nodule development, we observed an accumulation of trehalose-phosphate at 21 days post infection (dpi. Moreover, nodules from non-nitrogen-fixing bacteroids (nifA and nifH mutants showed specific metabolic alterations; these were also supported by independent transcriptomics data. The alterations included signs of nitrogen limitation in both mutants, and an increased level of a phytoalexin in nodules induced by the nifA mutant, suggesting that the tissue of these nodules exhibits defense and stress reactions.

  20. Photosynthetic Bradyrhizobium sp. Strain ORS285 Is Capable of Forming Nitrogen-Fixing Root Nodules on Soybeans (Glycine max)

    Science.gov (United States)

    Giraud, Eric; Xu, Lei; Chaintreuil, Clémence; Gargani, Daniel; Gully, Djamel

    2013-01-01

    The ability of photosynthetic Bradyrhizobium strains ORS285 and ORS278 to nodulate soybeans was investigated. While the nod gene-deficient ORS278 strain induced bumps only on soybean roots, the nod gene-containing ORS285 strain formed nitrogen-fixing nodules. However, symbiotic efficiencies differed drastically depending on both the soybean genotype used and the culture conditions tested. PMID:23354704

  1. Diversity of Frankia populations in root nodules of geographically isolated Arizona alder trees in central Arizona (United States)

    Science.gov (United States)

    Allana K. Welsh; Jeffrey O. Dawson; Gerald J. Gottfried; Dittmar Hahn

    2009-01-01

    The diversity of uncultured Frankia populations in root nodules of Alnus oblongifolia trees geographically isolated on mountaintops of central Arizona was analyzed by comparative sequence analyses of nifH gene fragments. Sequences were retrieved from Frankia populations in nodules of four trees from each of...

  2. Quantitative modelling of legume root nodule primordium induction by a diffusive signal of epidermal origin that inhibits auxin efflux

    NARCIS (Netherlands)

    Deinum, Eva E.; Kohlen, Wouter; Geurts, René

    2016-01-01

    Background: Rhizobium nitrogen fixation in legumes takes place in specialized organs called root nodules. The initiation of these symbiotic organs has two important components. First, symbiotic rhizobium bacteria are recognized at the epidermis through specific bacterially secreted

  3. Ensifer shofinae sp. nov., a novel rhizobial species isolated from root nodules of soybean (Glycine max).

    Science.gov (United States)

    Chen, Wen Hao; Yang, Sheng Hui; Li, Zhao Hu; Zhang, Xiao Xia; Sui, Xin Hua; Wang, En Tao; Chen, Wen Xin; Chen, Wen Feng

    2017-04-01

    Two bacterial strains isolated from root nodules of soybean were characterized phylogenetically as members of a distinct group in the genus Ensifer based on 16S rRNA gene comparisons. They were also verified as a separated group by the concatenated sequence analyses of recA, atpD and glnII (with similarities ≤93.9% to the type strains for defined species), and by the average nucleotide identities (ANI) between the whole genome sequence of the representative strain CCBAU 251167 T and those of the closely related strains in Ensifer glycinis and Ensifer fredii (90.5% and 90.3%, respectively). Phylogeny of symbiotic genes (nodC and nifH) grouped these two strains together with some soybean-nodulating strains of E. fredii, E. glycinis and Ensifer sojae. Nodulation tests indicated that the representative strain CCBAU 251167 T could form root nodules with capability of nitrogen fixing on its host plant and Glycine soja, Cajanus cajan, Vigna unguiculata, Phaseolus vulgaris and Astragalus membranaceus, and it formed ineffective nodules on Leucaena leucocephala. Strain CCBAU 251167 T contained fatty acids 18:1 ω9c, 18:0 iso and 20:0, differing from other related strains. Utilization of l-threonine and d-serine as carbon source, growth at pH 6.0 and intolerance of 1% (w/v) NaCl distinguished strain CCBAU 251167 T from other type strains of the related species. The genome size of CCBAU 251167 T was 6.2Mbp, comprising 7,581 predicted genes with DNA G+C content of 59.9mol% and 970 unique genes. Therefore, a novel species, Ensifer shofinae sp. nov., is proposed, with CCBAU 251167 T (=ACCC 19939 T =LMG 29645 T ) as type strain. Copyright © 2017 Elsevier GmbH. All rights reserved.

  4. The ethylene-inhibitor aminoethoxyvinylglycine restores normal nodulation by Rhizobium leguminosarum biovar. viciae on Vicia sativa subsp. nigra by suppressing the 'Thick and short roots' phenotype.

    Science.gov (United States)

    Zaat, S A; Van Brussel, A A; Tak, T; Lugtenberg, B J; Kijne, J W

    1989-02-01

    Nodulation of Vicia sativa subsp. nigra L. by Rhizobium bacteria is coupled to the development of thick and short roots (Tsr). This root phenotype as well as root-hair induction (Hai) and root-hair deformation (Had) are caused by a factor(s) produced by the bacteria in response to plant flavonoids. When very low inoculum concentrations (0.5-5 bacteria·ml(-1)) were used, V. sativa plants did not develop the Tsr phenotype and became nodulated earlier than plants with Tsr roots. Furthermore, the nodules of these plants were located on the primary root in contrast to nodules on Tsr roots, which were all located at sites of lateral-root emergence. The average numbers of nodules per plant were not significantly different for these two types of nodulation. Root-growth inhibition and Hai, but not Had, could be mimicked by ethephon, and inhibited by aminoethoxyvinylglycine (AVG). Addition of AVG to co-cultures of Vicia sativa and the standard inoculum concentration of 5·10(5) bacteria·ml(-1) suppressed the development of the Tsr phenotype and restored nodulation to the pattern that was observed with very low concentrations of bacteria (0.5-5 bacteria·ml(-1)). The delay in nodulation on Tsr roots appeared to be caused by the fact that nodule meristems did not develop on the primary root, but only on the emerging laterals. The relationship between Tsr, Hai, Had, and nodulation is discussed.

  5. Paraquat Toxicity on Root Nodule Formation on Macroptiliuma tropurpureum Urb. and Its Corelation with Population of Rhizobium sp.

    Directory of Open Access Journals (Sweden)

    Erni Martani

    2004-12-01

    Full Text Available This study was designed to investigate the paraquat toxicity toward root nodulation by Rhizobium on Macroptilium atropurpureum as an indicator plant. The legume was grown in Thornton medium treated with several concentrations of paraquat and inoculated with R.japonicum 143 (Rj-143 or Rhizobium sp. C-1.1. These bacteria represent cross-inoculation of soybean and cover-crops legumes, respectively. Nodule formation and Rhizobium population were measured periodically. At the end of planting time, nitrogenase activity of the nodules was analysis based on ARA (Acethylene Reduction Analysis method. The results showed that nodules in plants inoculated with Rhizobium without addition paraquat, were formed within four weeks. There was no nodulation when paraquat was added. Paraquat was toxic to the plant, causing chlorosis, stunting, drying of the plant tissues, and death. The symptoms were detected at the second week after planting time. Paraquat also decreased Rhizobium population from 10^6 to 10^2 or 10^1 CFU/mL at 40 and 100 pp, respectively. These results depicted that paraquat disturbed the plant before nodulation, and at the same time Rhizobium populatin decreased until below minimal population required for nodulation. Therefore, the process of nodulation was disturbed, and in some treatments there was nodulation. It was concluded that paraquat was toxic to both plant and the Rhizobium, which cause nodulation failure.

  6. Physiological roles of glutathione s-transferases in soybean root nodules.

    Science.gov (United States)

    Dalton, David A; Boniface, Chris; Turner, Zachary; Lindahl, Amy; Kim, Hyeon Jeong; Jelinek, Laura; Govindarajulu, Manjula; Finger, Richard E; Taylor, Christopher G

    2009-05-01

    Glutathione S-transferases (GSTs) are ubiquitous enzymes that catalyze the conjugation of toxic xenobiotics and oxidatively produced compounds to reduced glutathione, which facilitates their metabolism, sequestration, or removal. We report here that soybean (Glycine max) root nodules contain at least 14 forms of GST, with GST9 being most prevalent, as measured by both real-time reverse transcription-polymerase chain reaction and identification of peptides in glutathione-affinity purified extracts. GST8 was prevalent in stems and uninfected roots, whereas GST2/10 prevailed in leaves. Purified, recombinant GSTs were shown to have wide-ranging kinetic properties, suggesting that the suite of GSTs could provide physiological flexibility to deal with numerous stresses. Levels of GST9 increased with aging, suggesting a role related to senescence. RNA interference studies of nodules on composite plants showed that a down-regulation of GST9 led to a decrease in nitrogenase (acetylene reduction) activity and an increase in oxidatively damaged proteins. These findings indicate that GSTs are abundant in nodules and likely function to provide antioxidant defenses that are critical to support nitrogen fixation.

  7. Diversity and numbers of root-nodule bacteria (rhizobia in Polish soils

    Directory of Open Access Journals (Sweden)

    Stefan Martyniuk

    2011-01-01

    Full Text Available Using a sand pouch-plant infection method, populations of several species of root-nodule bacteria (rhizobia were enumerated in eighty soils collected throughout Poland. Rhizobium leguminosarum bv. viciae (symbionts of pea, faba bean, vetch and R. leguminosarum bv. trifolii (symbionts of clover were detected in 77 and 76 soils, respectively. Most of these soils contained moderate and high numbers of these species of the rhizobia. Symbionts of beans, R. leguminosarum bv. phaseoli, were assessed in 76 soils; of this number 15 soils had no detectable populations of bean rhizobia and in 40 soils high or moderate numbers of these bacteria were found. Bradyrhizobium sp. (Lupinus, root-nodule bacteria of lupine and serradella, were absent in 19 soils, out of 80 tested, and 34 soils were colonised by high or moderate populations of bradyrhizobia. Sinorhizobium meliloti, rhizobia nodulating alfalfa, were sparse in the examined soils; with 56 soil containing no detectable numbers of S. meliloti and only 6 soils harbouring high or moderate populations of this species. The estimated numbers of the rhizobia in the studied soils were also related to some physical and chemical properties of these soils.

  8. Bradyrhizobium ottawaense sp. nov., a symbiotic nitrogen fixing bacterium from root nodules of soybeans in Canada.

    Science.gov (United States)

    Yu, Xiumei; Cloutier, Sylvie; Tambong, James T; Bromfield, Eden S P

    2014-09-01

    Sixteen strains of symbiotic bacteria from root nodules of Glycine max grown in Ottawa, Canada, were previously characterized and placed in a novel group within the genus Bradyrhizobium. To verify their taxonomic status, these strains were further characterized using a polyphasic approach. All strains possessed identical 16S rRNA gene sequences that were 99.79 % similar to the closest relative, Bradyrhizobium liaoningense LMG 18230(T). Phylogenetic analysis of concatenated atpD, glnII, recA, gyrB, rpoB and dnaK genes divided the 16 strains into three multilocus sequence types that were placed in a highly supported lineage distinct from named species of the genus Bradyrhizobium consistent with results of DNA-DNA hybridization. Based on analysis of symbiosis gene sequences (nodC and nifH), all novel strains were placed in a phylogenetic group with five species of the genus Bradyrhizobium that nodulate soybeans. The combination of phenotypic characteristics from several tests including carbon and nitrogen source utilization and antibiotic resistance could be used to differentiate representative strains from recognized species of the genus Bradyrhizobium. Novel strain OO99(T) elicits effective nodules on Glycine max, Glycine soja and Macroptilium atropurpureum, partially effective nodules on Desmodium canadense and Vigna unguiculata, and ineffective nodules on Amphicarpaea bracteata and Phaseolus vulgaris. Based on the data presented, we conclude that our strains represent a novel species for which the name Bradyrhizobium ottawaense sp. nov. is proposed, with OO99(T) ( = LMG 26739(T) = HAMBI 3284(T)) as the type strain. The DNA G+C content is 62.6 mol%. © 2014 Her Majesty the Queen in right of Canada as represented by the Minister of AAFC.

  9. Bradyrhizobium ottawaense sp. nov., a symbiotic nitrogen fixing bacterium from root nodules of soybeans in Canada

    Science.gov (United States)

    Yu, Xiumei; Cloutier, Sylvie; Tambong, James T.

    2014-01-01

    Sixteen strains of symbiotic bacteria from root nodules of Glycine max grown in Ottawa, Canada, were previously characterized and placed in a novel group within the genus Bradyrhizobium. To verify their taxonomic status, these strains were further characterized using a polyphasic approach. All strains possessed identical 16S rRNA gene sequences that were 99.79 % similar to the closest relative, Bradyrhizobium liaoningense LMG 18230T. Phylogenetic analysis of concatenated atpD, glnII, recA, gyrB, rpoB and dnaK genes divided the 16 strains into three multilocus sequence types that were placed in a highly supported lineage distinct from named species of the genus Bradyrhizobium consistent with results of DNA–DNA hybridization. Based on analysis of symbiosis gene sequences (nodC and nifH), all novel strains were placed in a phylogenetic group with five species of the genus Bradyrhizobium that nodulate soybeans. The combination of phenotypic characteristics from several tests including carbon and nitrogen source utilization and antibiotic resistance could be used to differentiate representative strains from recognized species of the genus Bradyrhizobium. Novel strain OO99T elicits effective nodules on Glycine max, Glycine soja and Macroptilium atropurpureum, partially effective nodules on Desmodium canadense and Vigna unguiculata, and ineffective nodules on Amphicarpaea bracteata and Phaseolus vulgaris. Based on the data presented, we conclude that our strains represent a novel species for which the name Bradyrhizobium ottawaense sp. nov. is proposed, with OO99T ( = LMG 26739T = HAMBI 3284T) as the type strain. The DNA G+C content is 62.6 mol%. PMID:24969302

  10. Root Exudates of Various Host Plants of Rhizobium leguminosarum Contain Different Sets of Inducers of Rhizobium Nodulation Genes

    NARCIS (Netherlands)

    Zaat, Sebastian A. J.; Wijffelman, Carel A.; Mulders, Ine H. M.; van Brussel, Anton A. N.; Lugtenberg, Ben J. J.

    1988-01-01

    Rhizobium promoters involved in the formation of root nodules on leguminous plants are activated by flavonoids in plant root exudate. A series of Rhizobium strains which all contain the inducible Rhizobium leguminosarum nodA promoter fused to the Escherichia coli lacZ gene, and which differ only in

  11. Induced systemic resistance against Botrytis cinerea by Micromonospora strains isolated from root nodules

    Directory of Open Access Journals (Sweden)

    Pilar eMartínez-Hidalgo

    2015-09-01

    Full Text Available Micromonospora is a Gram positive bacterium that can be isolated from nitrogen fixing nodules from healthy leguminous plants, where they could be beneficial to the plant. Their plant growth promoting activity in legume and non-legume plants has been previously demonstrated. The present study explores the ability of Micromonospora strains to control fungal pathogens and to stimulate plant immunity. Micromonospora strains isolated from surface sterilized nodules of alfalfa showed in vitro antifungal activity against several pathogenic fungi. Moreover, root inoculation of tomato plants with these Micromonospora strains effectively reduced leaf infection by the fungal pathogen Botrytis cinerea, despite spatial separation between both microorganisms. This induced systemic resistance, confirmed in different tomato cultivars, is long lasting. Gene expression analyses evidenced that Micromonospora stimulates the plant capacity to activate defense mechanisms upon pathogen attack. The defensive response of tomato plants inoculated with Micromonospora spp. differs from that of non-inoculated plants, showing a stronger induction of jasmonate-regulated defenses when the plant is challenged with a pathogen. The hypothesis of jasmonates playing a key role in this defense priming effect was confirmed using defense-impaired tomato mutants, since the JA-deficient line def1 was unable to display a long term induced resistance upon Micromonospora spp. inoculation.In conclusion, nodule isolated Micromonospora strains should be considered excellent candidates as biocontrol agents as they combine both direct antifungal activity against plant pathogens and the ability to prime plant immunity.

  12. Paraquat Toxicity on Root Nodule Formation on Macroptiliuma Tropurpureum Urb. and Its Corelation with Population of Rhizobium SP.

    OpenAIRE

    Martani, Erni; Margino, Sebastian; Magdalena, Medhina

    2004-01-01

    This study was designed to investigate the paraquat toxicity toward root nodulation by Rhizobium on Macroptilium atropurpureum as an indicator plant. The legume was grown in Thornton medium treated with several concentrations of paraquat and inoculated with R.japonicum 143 (Rj-143) or Rhizobium sp. C-1.1. These bacteria represent cross-inoculation of soybean and cover-crops legumes, respectively. Nodule formation and Rhizobium population were measured periodically. At the end of planting time...

  13. Virus-induced gene silencing (VIGS) as a reverse genetic tool to study development of symbiotic root nodules

    DEFF Research Database (Denmark)

    Kjær, Gabriela Didina Constantin; Grønlund, Mette; Stougaard, Jens

    2008-01-01

    Virus-induced gene silencing (VIGS) can provide a shortcut to plants with altered expression of specific genes. Here, we report that VIGS of the Nodule inception gene (Nin) can alter the nodulation phenotype and Nin gene expression in Pisum sativum. PsNin was chosen as target because of the disti......NinB, nodulation was reduced by at least 45%. Down-regulation of PsNin transcripts in plants inoculated with vectors carrying PsNin cDNA fragments was confirmed and these plants displayed a relative increase in the root/shoot ratio, as expected if nitrogen fixation had been impaired....

  14. Lead Tolerance and Accumulation in Hirschfeldia incana, a Mediterranean Brassicaceae from Metalliferous Mine Spoils

    Science.gov (United States)

    Auguy, Florence; Fahr, Mouna; Moulin, Patricia; Brugel, Anaïs; Laplaze, Laurent; Mzibri, Mohamed El; Filali-Maltouf, Abdelkarim; Doumas, Patrick; Smouni, Abdelaziz

    2013-01-01

    Lead is a heavy metal of particular concern with respect to environmental quality and health. The lack of plant species that accumulate and tolerate Pb is a limiting factor to understand the molecular mechanisms involved in Pb tolerance. In this study we identified Hirschfeldia incana, a Brassicaceae collected from metalliferous mine spoils in Morocco, as a Pb accumulator plant. H. incana exhibited high Pb accumulation in mine soils and in hydroponic cultures. Major Pb accumulation occurred in the roots and a part of Pb translocated from the roots to the shoots, even to the siliques. These findings demonstrated that H. incana is a Pb accumulator species. The expression of several candidate genes after Pb-exposure was measured by quantitative PCR and two of them, HiHMA4 and HiMT2a, coding respectively for a P1B-type ATPase and a metallothionein, were particularly induced by Pb-exposure in both roots and leaves. The functional characterization of HiHMA4 and HiMT2a was achieved using Arabidopsis T-DNA insertional mutants. Pb content and primary root growth analysis confirmed the role of these two genes in Pb tolerance and accumulation. H. incana could be considered as a good experimental model to identify genes involved in lead tolerance and accumulation in plants. PMID:23667449

  15. Possible role of glutamine synthetase in the NO signaling response in root nodules by contributing to the antioxidant defenses

    Directory of Open Access Journals (Sweden)

    Liliana Santos Silva

    2013-09-01

    Full Text Available Nitric oxide (NO is emerging as an important regulatory player in the Rhizobium-legume symbiosis. The occurrence of NO during several steps of the symbiotic interaction suggests an important, but yet unknown, signaling role of this molecule for root nodule formation and functioning. The identification of the molecular targets of NO is key for the assembly of the signal transduction cascade that will ultimately help to unravel NO function. We have recently shown that the key nitrogen assimilatory enzyme Glutamine Synthetase (GS is a molecular target of NO in root nodules of Medicago truncatula, being post-translationally regulated by tyrosine nitration in relation to nitrogen fixation. In functional nodules of M. truncatula NO formation has been located in the bacteroid containing cells of the fixation zone, where the ammonium generated by bacterial nitrogenase is released to the plant cytosol and assimilated into the organic pools by plant GS. We propose that the NO-mediated GS post-translational inactivation is connected to nitrogenase inhibition induced by NO and is related to metabolite channeling to boost the nodule antioxidant defenses. Glutamate, a substrate for GS activity is also the precursor for the synthesis of glutathione (GSH, which is highly abundant in root nodules of several plant species and known to play a major role in the antioxidant defense participating in the ascorbate/GSH cycle. Existing evidence suggests that upon NO-mediated GS inhibition, glutamate could be channeled for the synthesis of GSH. According to this hypothesis, GS would be involved in the NO-signaling responses in root nodules and the NO-signaling events would meet the nodule metabolic pathways to provide an adaptive response to the inhibition of symbiotic nitrogen fixation by reactive nitrogen species (RNS.

  16. GC-MS based metabolite profiling implies three interdependent ways of ammonium assimilation in Medicago truncatula root nodules.

    Science.gov (United States)

    Barsch, Aiko; Carvalho, Helena G; Cullimore, Julie V; Niehaus, Karsten

    2006-12-15

    In symbiotic interaction with legume plants, bacteria termed Rhizobia can fix massive amounts of atmospheric nitrogen which is primarily provided in the form of ammonium to the host plants. Therefore, legume root nodules that house the symbiotic bacteria are ideally suited to study the process of primary ammonium assimilation. Here, we present a GC-MS based metabolite profiling analysis of Medicago truncatula root nodules (induced by the bacterium Sinorhizobium meliloti) before and after inhibition of glutamine synthetase (GS) by the chemical herbicide phosphinotricine. The primary role of GS in ammonium assimilation was revealed by drastically reduced levels of glutamine in phosphinotricine treated root nodules. In comparison to previous results of increased asparagine synthetase transcript and protein abundances in GS inhibited nodules the metabolic data revealed that decreased amounts of aspartate might preclude taking advantage of this elevated enzymatic activity. A potential role of glutamate dehydrogenase in ammonium assimilation was metabolically indicated 24 and 48 h after GS inhibition. Therefore, nodule ammonium assimilation might in principle involve three interdependent metabolic pathways which are adjusted to control basic nitrogen metabolism.

  17. Rhizobium taibaishanense sp. nov., isolated from a root nodule of Kummerowia striata.

    Science.gov (United States)

    Yao, Li Juan; Shen, Yao Yao; Zhan, Jun Peng; Xu, Wei; Cui, Guang Ling; Wei, Ge Hong

    2012-02-01

    During a study of the diversity and phylogeny of rhizobia in the root nodules of Kummerowia striata grown in north-western China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. The 16S rRNA gene sequences of three of these strains were identical and that of the other strain, which was the only one isolated in Yangling, differed from the others by just 1 bp. The16S rRNA gene sequences of the four strains showed a mean similarity of 99.3 % with the most closely related, recognized species, Rhizobium vitis. The corresponding recA and glnA gene sequences showed similarities with established species of Rhizobium of less than 86.5 % and less than 89.6 %, respectively. These low similarities indicated that the four strains represented a novel species of the genus Rhizobium. The strains were also found to be distinguishable from the closest related, established species (R. vitis) by rep-PCR DNA fingerprinting, analysis of cellular fatty acid profiles and from the results of a series of phenotypic tests. The level of DNA-DNA relatedness between the representative strain CCNWSX 0483(T) and Rhizobium vitis IAM 14140(T) was only 40.13 %. Therefore, a novel species, Rhizobium taibaishanense sp. nov., is proposed, with strain CCNWSX 0483(T) ( = ACCC 14971(T) = HAMBI 3214(T)) as the type strain. In nodulation and pathogenicity tests, none of the four strains of Rhizobium taibaishanense sp. nov. was able to induce any nodule or tumour formation on plants. As no amplicons were detected when DNA from the strains was run in PCR with primers for the detection of nodA, nifH and virC gene sequences, the strains probably do not carry sym or vir genes.

  18. Bradyrhizobium subterraneum sp. nov., a symbiotic nitrogen-fixing bacterium from root nodules of groundnuts.

    Science.gov (United States)

    Grönemeyer, Jann Lasse; Chimwamurombe, Percy; Reinhold-Hurek, Barbara

    2015-10-01

    Seven strains of symbiotic bacteria from root nodules of local races of Bambara groundnut (Vigna subterranea) and peanuts (Arachis hypogaea) grown on subsistence farmers' fields in the Kavango region, Namibia, were previously characterized and identified as a novel group within the genus Bradyrhizobium. To corroborate their taxonomic status, these strains were further characterized using a polyphasic approach. All strains possessed identical 16S rRNA gene sequences with Bradyrhizobium yuanmingense CCBAU 10071T being the most closely related type strain in the 16S rRNA gene phylogenetic analysis, and Bradyrhizobium daqingense CCBAU 15774T in the ITS sequence analysis. Phylogenetic analysis of concatenated glnII-recA-rpoB-dnaK placed the strains in a highly supported lineage distinct from named species of the genus Bradyrhizobium, most closely related to Bradyrhizobium yuanmingense CCBAU 10071T. The species status was validated by results of DNA–DNA hybridization. Phylogenetic analysis of nifH genes placed the novel strains in a group with nifH of ‘Bradyrhizobium arachidis’ CCBAU 051107 that also nodulates peanuts. The combination of phenotypic characteristics from several tests including carbon source utilization and antibiotic resistance could be used to differentiate representative strains from recognized species of the genus Bradyrhizobium. Novel strain 58 2-1T induced effective nodules on V. subterranea, Vigna unguiculata and A. hypogaea, and some strains on Lablab purpureus. Based on the data presented, we conclude that our strains represent a novel species for which the name Bradyrhizobium subterraneum sp. nov. is proposed, with 58 2-1T [ = DSM 100298T = LMG 28792T = NTCCM0016T (Windhoek)] as the type strain. The DNA G+C content of strain 58 2-1T was 64.7 mol% (T m).

  19. A Genomic Encyclopedia of the Root Nodule Bacteria: assessing genetic diversity through a systematic biogeographic survey.

    Science.gov (United States)

    Reeve, Wayne; Ardley, Julie; Tian, Rui; Eshragi, Leila; Yoon, Je Won; Ngamwisetkun, Pinyaruk; Seshadri, Rekha; Ivanova, Natalia N; Kyrpides, Nikos C

    2015-01-01

    Root nodule bacteria are free-living soil bacteria, belonging to diverse genera within the Alphaproteobacteria and Betaproteobacteria, that have the capacity to form nitrogen-fixing symbioses with legumes. The symbiosis is specific and is governed by signaling molecules produced from both host and bacteria. Sequencing of several model RNB genomes has provided valuable insights into the genetic basis of symbiosis. However, the small number of sequenced RNB genomes available does not currently reflect the phylogenetic diversity of RNB, or the variety of mechanisms that lead to symbiosis in different legume hosts. This prevents a broad understanding of symbiotic interactions and the factors that govern the biogeography of host-microbe symbioses. Here, we outline a proposal to expand the number of sequenced RNB strains, which aims to capture this phylogenetic and biogeographic diversity. Through the Vavilov centers of diversity (Proposal ID: 231) and GEBA-RNB (Proposal ID: 882) projects we will sequence 107 RNB strains, isolated from diverse legume hosts in various geographic locations around the world. The nominated strains belong to nine of the 16 currently validly described RNB genera. They include 13 type strains, as well as elite inoculant strains of high commercial importance. These projects will strongly support systematic sequence-based studies of RNB and contribute to our understanding of the effects of biogeography on the evolution of different species of RNB, as well as the mechanisms that determine the specificity and effectiveness of nodulation and symbiotic nitrogen fixation by RNB with diverse legume hosts.

  20. The salt-responsive transcriptome of chickpea roots and nodules via deepSuperSAGE

    Directory of Open Access Journals (Sweden)

    Steinhauer Diana

    2011-02-01

    Full Text Available Abstract Background The combination of high-throughput transcript profiling and next-generation sequencing technologies is a prerequisite for genome-wide comprehensive transcriptome analysis. Our recent innovation of deepSuperSAGE is based on an advanced SuperSAGE protocol and its combination with massively parallel pyrosequencing on Roche's 454 sequencing platform. As a demonstration of the power of this combination, we have chosen the salt stress transcriptomes of roots and nodules of the third most important legume crop chickpea (Cicer arietinum L.. While our report is more technology-oriented, it nevertheless addresses a major world-wide problem for crops generally: high salinity. Together with low temperatures and water stress, high salinity is responsible for crop losses of millions of tons of various legume (and other crops. Continuously deteriorating environmental conditions will combine with salinity stress to further compromise crop yields. As a good example for such stress-exposed crop plants, we started to characterize salt stress responses of chickpeas on the transcriptome level. Results We used deepSuperSAGE to detect early global transcriptome changes in salt-stressed chickpea. The salt stress responses of 86,919 transcripts representing 17,918 unique 26 bp deepSuperSAGE tags (UniTags from roots of the salt-tolerant variety INRAT-93 two hours after treatment with 25 mM NaCl were characterized. Additionally, the expression of 57,281 transcripts representing 13,115 UniTags was monitored in nodules of the same plants. From a total of 144,200 analyzed 26 bp tags in roots and nodules together, 21,401 unique transcripts were identified. Of these, only 363 and 106 specific transcripts, respectively, were commonly up- or down-regulated (>3.0-fold under salt stress in both organs, witnessing a differential organ-specific response to stress. Profiting from recent pioneer works on massive cDNA sequencing in chickpea, more than 9,400 Uni

  1. Localization of acid phosphatase activity in the apoplast of root nodules of pea (Pisum sativum

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    Marzena Sujkowska

    2011-01-01

    Full Text Available Changes in the activity of acid phosphatase (AcPase in the apoplast of pea root nodule were investigated. The activity was determined using lead and cerium methods. The results indicated a following sequence of AcPase activity appearance during the development of the infection thread: 1 low AcPase activity appears in the outer part of cells of symbiotic bacteria; 2 bacteria show increased AcPase activity, and the enzyme activity appears in the thread walls; 3 activity exhibits also matrix of the infection thread; 4 bacteria just before their release from the infection threads show high AcPase activity; 5 AcPase activity ceases after bacteria transformation into bacteroids. The increase in bacterial AcPase activity may reflect a higher demand for inorganic phosphorus necessary for propagation of the bacteria within the infection threads and/or involved in bacteria release from the infection threads.

  2. Rhizobium favelukesii sp. nov., isolated from the root nodules of alfalfa (Medicago sativa L).

    Science.gov (United States)

    Torres Tejerizo, Gonzalo; Rogel, Marco Antonio; Ormeño-Orrillo, Ernesto; Althabegoiti, María Julia; Nilsson, Juliet Fernanda; Niehaus, Karsten; Schlüter, Andreas; Pühler, Alfred; Del Papa, María Florencia; Lagares, Antonio; Martínez-Romero, Esperanza; Pistorio, Mariano

    2016-11-01

    Strains LPU83T and Or191 of the genus Rhizobium were isolated from the root nodules of alfalfa, grown in acid soils from Argentina and the USA. These two strains, which shared the same plasmid pattern, lipopolysaccharide profile, insertion-sequence fingerprint, 16S rRNA gene sequence and PCR-fingerprinting pattern, were different from reference strains representing species of the genus Rhizobium with validly published names. On the basis of previously reported data and from new DNA-DNA hybridization results, phenotypic characterization and phylogenetic analyses, strains LPU83T and Or191 can be considered to be representatives of a novel species of the genus Rhizobium, for which the name Rhizobium favelukesii sp. nov. is proposed. The type strain of this species is LPU83T (=CECT 9014T=LMG 29160T), for which an improved draft-genome sequence is available.

  3. Occurrence of polyamines in root nodules of Phaseolus vulgaris in symbiosis with Rhizobium tropici in response to salt stress.

    Science.gov (United States)

    López-Gómez, Miguel; Cobos-Porras, Libertad; Hidalgo-Castellanos, Javier; Lluch, Carmen

    2014-11-01

    Polyamines (PAs) are low molecular weight aliphatic compounds that have been shown to be an important part of plant responses to salt stress. For that reason in this work we have investigated the involvement of PAs in the response to salt stress in root nodules of Phaseolus vulgaris in symbiosis with Rhizobium tropici. The level and variety of PAs was higher in nodules, compared to leaves and roots, and in addition to the common PAs (putrescine, spermidine and spermine) we found homospermidine (Homspd) as the most abundant polyamine in nodules. UPLC-mass spectrometry analysis revealed the presence of 4-aminobutylcadaverine (4-ABcad), only described in nodules of Vigna angularis before. Indeed, the analysis of different nodular fractions revealed higher level of 4-ABcad, as well as Homspd, in bacteroids which indicate the production of these PAs by the bacteria in symbiosis. The genes involved in PAs biosynthesis in nodules displayed an induction under salt stress conditions which was not consistent with the decline of free PAs levels, probably due to the nitrogen limitations provoked by the nitrogenase activity depletion and/or the conversion of free PAs to theirs soluble conjugated forms, that seems to be one of the mechanisms involved in the regulation of PAs levels. On the contrary, cadaverine (Cad) and 4-ABcad concentrations augmented by the salinity, which might be due to their involvement in the response of bacteroids to hyper-osmotic conditions. In conclusion, the results shown in this work suggest the alteration of the bacteroidal metabolism towards the production of uncommon PAs such as 4-ABcad in the response to salt stress in legume root nodules. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. The ethylene-inhibitor aminoethoxyvinylglycine restores normal nodulation by Rhizobium leguminosarum biovar. viciae on Vicia sativa subsp. nigra by suppressing the 'Thick and short roots' phenotype

    NARCIS (Netherlands)

    Zaat, S. A.; van Brussel, A. A.; Tak, T.; Lugtenberg, B. J.; KIJNE, J. W.

    1989-01-01

    Nodulation of Vicia sativa subsp. nigra L. by Rhizobium bacteria is coupled to the development of thick and short roots (Tsr). This root phenotype as well as root-hair induction (Hai) and root-hair deformation (Had) are caused by a factor(s) produced by the bacteria in response to plant flavonoids.

  5. Redox regulation of peroxiredoxin and proteinases by ascorbate and thiols during pea root nodule senescence.

    Science.gov (United States)

    Groten, Karin; Dutilleul, Christelle; van Heerden, Philippus D R; Vanacker, Hélène; Bernard, Stéphanie; Finkemeier, Iris; Dietz, Karl-Josef; Foyer, Christine H

    2006-02-20

    Redox factors contributing to nodule senescence were studied in pea. The abundance of the nodule cytosolic peroxiredoxin but not the mitochondrial peroxiredoxin protein was modulated by ascorbate. In contrast to redox-active antioxidants such as ascorbate and cytosolic peroxiredoxin that decreased during nodule development, maximal extractable nodule proteinase activity increased progressively as the nodules aged. Cathepsin-like activities were constant throughout development but serine and cysteine proteinase activities increased during senescence. Senescence-induced cysteine proteinase activity was inhibited by cysteine, dithiotreitol, or E-64. Senescence-dependent decreases in redox-active factors, particularly ascorbate and peroxiredoxin favour decreased redox-mediated inactivation of cysteine proteinases.

  6. Effect of cropping systems and arbuscular mycorrhizal fungi on soil microbial activity and root nodule nitrogenase

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Zarea

    2011-06-01

    Full Text Available Forage legumes are used to enhancement soil fertility of the agro ecosystem. Understanding effect of them on agro ecosystem soil status during when these legumes growing and after that is essential. In one experiment the effects of inoculation with the arbuscular mycorrhizal fungi (AMF, Glomus mosseae, and mixed cropping systems (MCS on forage biomass yield, nitrogen production, nitrogenase activity and after harvesting on soil microbial activity were studied at various mixed cropping ratios of berseem clover (Trifolium alexandrinum L., B to Persian clover (Trifolium resupinatum L., P (B:P = 1:0, 3:1, 1:1, and 1:3. In the second experiment, the effect of treatments on soil microbial activity were studied by soil collection after clover harvesting and 8-week soil incubations in the laboratory. MCS had positive effects on root and shoot dry weight. The effects of AMF on plant yield were positive. AMF affected the fraction root and the vertical root distribution. Plants colonized by AMF showed shorter roots than control plants. At cut 1, with the AMF colonization, the greatest nitrogenase activity (79.61 μmol C2H4 g dwt−1 h−1 of root nodule was observed with B:P = 3:1. At cut 2, the Persian clover plants colonized by G. mosseae in the mixed crop (1:3 had a higher nitrogenase activity (77.38 μmol C2H4 g dwt−1 h−1. The greatest nitrogen accumulation in the aboveground biomass, 23.5 mg g−1 forage dry matter, was obtained with mixed cropping (B:P = 1:1 in the presence of the AMF colonization. Microbial activity measured as substrate-induced respiration and activities of dehydrogenase, alkaline phosphatase, and acid phosphatase enzymes responded positively to AMF colonization; with the greatest activities for B:P = 1:3.

  7. Bacillus radicibacter sp. nov., a new bacterium isolated from root nodule of Oxytropis ochrocephala Bunge.

    Science.gov (United States)

    Wei, Xiu Li; Lin, Yan Bing; Xu, Lin; Han, Meng Sha; Dong, Dan Hong; Chen, Wei Min; Wang, Li; Wei, Ge Hong

    2015-10-01

    A Gram-positive, facultative anaerobic, rod-shaped, and endospore-forming strain, designated 53-2(T) was isolated from the root nodule of Oxytropis ochrocephala Bunge growing on Qilian mountain, China. The strain can grow at pH 7.0-8.0, 10-50 °C and tolerate up to 11% NaCl. Optimal growth occurred at pH 7.2 and 37 °C. The result of BLASTn search based on 16S rRNA gene sequence revealed that strain 53-2(T) , being closest related to Bacillus acidicola 105-2(T) , possessed remote similarity (less than 95.64%) to the species within genus Bacillus. The DNA G + C content was 37.8%. Chemotaxonomic data (major quinone is MK-7; major polar lipids are diphosphatidylglycerol, phosphatidylglycerol, unknown phospholipid, and aminoglycophospholipid; fatty acids are anteiso-C15: 0 , iso-C15:0 and anteiso-C17: 0 ) supported the affiliation of the isolate to the genus Bacillus. On the basis of physiological, phylogenetic, and biochemical properties, strain 53-2(T) represents a novel species within genus Bacillus, for which the name Bacillus radicibacter is proposed. The type strain is 53-2(T) (=DSM27302(T) =ACCC06115(T) =CCNWQLS5(T) ). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Computational investigation of small RNAs in the establishment of root nodules and arbuscular mycorrhiza in leguminous plants.

    Science.gov (United States)

    Jin, Danfeng; Meng, Xianwen; Wang, Yue; Wang, Jingjing; Zhao, Yuhua; Chen, Ming

    2018-01-03

    Many small RNAs have been confirmed to play important roles in the development of root nodules and arbuscular mycorrhiza. In this study, we carried out the identification of certain small RNAs in leguminous plants (Medicago truncatula, soybean, peanut and common bean), such as miRNAs, tRFs and srRNAs, as well as the computational investigation of their regulations. Thirty miRNAs were predicted to be involved in establishing root nodules and mycorrhiza, and 12 of them were novel in common bean and peanut. The generation of tRFs in M. truncatula was not associated with tRNA gene frequencies and codon usage. Six tRFs exhibited different expressions in mycorrhiza and root nodules. Moreover, srRNA 5.8S in M. truncatula was generated from the regions with relatively low conservation at the rRNA 3' terminal. The protein-protein interactions between the proteins encoded by the target genes of miRNAs, tRFs and srRNAs were computed. The regulation of these three types of sRNAs in the symbiosis between leguminous plants and microorganisms is not a single regulation of certain signaling or metabolic pathways but a global regulation for the plants to own growth or specific events in symbiosis.

  9. The independent acquisition of plant root nitrogen-fixing symbiosis in Fabids recruited the same genetic pathway for nodule organogenesis.

    Directory of Open Access Journals (Sweden)

    Sergio Svistoonoff

    Full Text Available Only species belonging to the Fabid clade, limited to four classes and ten families of Angiosperms, are able to form nitrogen-fixing root nodule symbioses (RNS with soil bacteria. This concerns plants of the legume family (Fabaceae and Parasponia (Cannabaceae associated with the Gram-negative proteobacteria collectively called rhizobia and actinorhizal plants associated with the Gram-positive actinomycetes of the genus Frankia. Calcium and calmodulin-dependent protein kinase (CCaMK is a key component of the common signaling pathway leading to both rhizobial and arbuscular mycorrhizal symbioses (AM and plays a central role in cross-signaling between root nodule organogenesis and infection processes. Here, we show that CCaMK is also needed for successful actinorhiza formation and interaction with AM fungi in the actinorhizal tree Casuarina glauca and is also able to restore both nodulation and AM symbioses in a Medicago truncatula ccamk mutant. Besides, we expressed auto-active CgCCaMK lacking the auto-inhibitory/CaM domain in two actinorhizal species: C. glauca (Casuarinaceae, which develops an intracellular infection pathway, and Discaria trinervis (Rhamnaceae which is characterized by an ancestral intercellular infection mechanism. In both species, we found induction of nodulation independent of Frankia similar to response to the activation of CCaMK in the rhizobia-legume symbiosis and conclude that the regulation of actinorhiza organogenesis is conserved regardless of the infection mode. It has been suggested that rhizobial and actinorhizal symbioses originated from a common ancestor with several independent evolutionary origins. Our findings are consistent with the recruitment of a similar genetic pathway governing rhizobial and Frankia nodule organogenesis.

  10. The Independent Acquisition of Plant Root Nitrogen-Fixing Symbiosis in Fabids Recruited the Same Genetic Pathway for Nodule Organogenesis

    Science.gov (United States)

    Svistoonoff, Sergio; Benabdoun, Faiza Meriem; Nambiar-Veetil, Mathish; Imanishi, Leandro; Vaissayre, Virginie; Cesari, Stella; Diagne, Nathalie; Hocher, Valérie; de Billy, Françoise; Bonneau, Jocelyne; Wall, Luis; Ykhlef, Nadia; Rosenberg, Charles; Bogusz, Didier; Franche, Claudine; Gherbi, Hassen

    2013-01-01

    Only species belonging to the Fabid clade, limited to four classes and ten families of Angiosperms, are able to form nitrogen-fixing root nodule symbioses (RNS) with soil bacteria. This concerns plants of the legume family (Fabaceae) and Parasponia (Cannabaceae) associated with the Gram-negative proteobacteria collectively called rhizobia and actinorhizal plants associated with the Gram-positive actinomycetes of the genus Frankia. Calcium and calmodulin-dependent protein kinase (CCaMK) is a key component of the common signaling pathway leading to both rhizobial and arbuscular mycorrhizal symbioses (AM) and plays a central role in cross-signaling between root nodule organogenesis and infection processes. Here, we show that CCaMK is also needed for successful actinorhiza formation and interaction with AM fungi in the actinorhizal tree Casuarina glauca and is also able to restore both nodulation and AM symbioses in a Medicago truncatula ccamk mutant. Besides, we expressed auto-active CgCCaMK lacking the auto-inhibitory/CaM domain in two actinorhizal species: C. glauca (Casuarinaceae), which develops an intracellular infection pathway, and Discaria trinervis (Rhamnaceae) which is characterized by an ancestral intercellular infection mechanism. In both species, we found induction of nodulation independent of Frankia similar to response to the activation of CCaMK in the rhizobia-legume symbiosis and conclude that the regulation of actinorhiza organogenesis is conserved regardless of the infection mode. It has been suggested that rhizobial and actinorhizal symbioses originated from a common ancestor with several independent evolutionary origins. Our findings are consistent with the recruitment of a similar genetic pathway governing rhizobial and Frankia nodule organogenesis. PMID:23741336

  11. Nodulation of leguminous plants as affected by root secretions and red light

    NARCIS (Netherlands)

    Lie, T.A.

    1964-01-01

    Nodulation of bean plants, Phaseolus vulgaris L., in water culture was poor during hot sunny weather in the greenhouse. It did not improve when indoleacetic acid, kinetin, gibberellic acid, purines and pyrimidines, yeast and soil extract were added. Nodulation was enhanced by adding used

  12. Mutation of praR in Rhizobium leguminosarum enhances root biofilms, improving nodulation competitiveness by increased expression of attachment proteins.

    Science.gov (United States)

    Frederix, Marijke; Edwards, Anne; Swiderska, Anna; Stanger, Andrew; Karunakaran, Ramakrishnan; Williams, Alan; Abbruscato, Pamela; Sanchez-Contreras, Maria; Poole, Philip S; Downie, J Allan

    2014-08-01

    In Rhizobium leguminosarum bv. viciae, quorum-sensing is regulated by CinR, which induces the cinIS operon. CinI synthesizes an AHL, whereas CinS inactivates PraR, a repressor. Mutation of praR enhanced biofilms in vitro. We developed a light (lux)-dependent assay of rhizobial attachment to roots and demonstrated that mutation of praR increased biofilms on pea roots. The praR mutant out-competed wild-type for infection of pea nodules in mixed inoculations. Analysis of gene expression by microarrays and promoter fusions revealed that PraR represses its own transcription and mutation of praR increased expression of several genes including those encoding secreted proteins (the adhesins RapA2, RapB and RapC, two cadherins and the glycanase PlyB), the polysaccharide regulator RosR, and another protein similar to PraR. PraR bound to the promoters of several of these genes indicating direct repression. Mutations in rapA2, rapB, rapC, plyB, the cadherins or rosR did not affect the enhanced root attachment or nodule competitiveness of the praR mutant. However combinations of mutations in rapA, rapB and rapC abolished the enhanced attachment and nodule competitiveness. We conclude that relief of PraR-mediated repression determines a lifestyle switch allowing the expression of genes that are important for biofilm formation on roots and the subsequent initiation of infection of legume roots. © 2014 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd.

  13. Mutation of praR in Rhizobium leguminosarum enhances root biofilms, improving nodulation competitiveness by increased expression of attachment proteins

    Science.gov (United States)

    Frederix, Marijke; Edwards, Anne; Swiderska, Anna; Stanger, Andrew; Karunakaran, Ramakrishnan; Williams, Alan; Abbruscato, Pamela; Sanchez-Contreras, Maria; Poole, Philip S; Downie, J Allan

    2014-01-01

    In Rhizobium leguminosarum bv. viciae, quorum-sensing is regulated by CinR, which induces the cinIS operon. CinI synthesizes an AHL, whereas CinS inactivates PraR, a repressor. Mutation of praR enhanced biofilms in vitro. We developed a light (lux)-dependent assay of rhizobial attachment to roots and demonstrated that mutation of praR increased biofilms on pea roots. The praR mutant out-competed wild-type for infection of pea nodules in mixed inoculations. Analysis of gene expression by microarrays and promoter fusions revealed that PraR represses its own transcription and mutation of praR increased expression of several genes including those encoding secreted proteins (the adhesins RapA2, RapB and RapC, two cadherins and the glycanase PlyB), the polysaccharide regulator RosR, and another protein similar to PraR. PraR bound to the promoters of several of these genes indicating direct repression. Mutations in rapA2, rapB, rapC, plyB, the cadherins or rosR did not affect the enhanced root attachment or nodule competitiveness of the praR mutant. However combinations of mutations in rapA, rapB and rapC abolished the enhanced attachment and nodule competitiveness. We conclude that relief of PraR-mediated repression determines a lifestyle switch allowing the expression of genes that are important for biofilm formation on roots and the subsequent initiation of infection of legume roots. PMID:24942546

  14. Nodulation of legumes, nitrogenase activity of roots and occurrence of nitrogen-fixing Azospirillum spp. In representative soils of central Amazonia

    Energy Technology Data Exchange (ETDEWEB)

    Sylvester-Bradley, R.; De Oliverira, L.A.; De Podesta Filho, J.A.; St. John, T.V.

    1980-12-01

    Leguminosae do not predominate in the Brazilian Amazon rain forest, although they are among the five best represented families. Plant roots from various soils were examined for the presence of nodules, acetylene-reducing activity and N/sub 2/-fixing Azospirillum spp. Abundant nodulation was found in black earth (''terra preta dos indios'') and in one case on sandy soil under campinarana vegetation along a tributary of the upper Rio Negro. In sandy latosol some nodules occurred in secondary forest and fewer in primary forest. Legumes in disturbed clayey or sandy latosol showed more frequent nodulation. Primary forest on alluvial (''varzea'') soil, and in Bahia coastal rain forest on sandy latosol and Erythrina glauca used for shading cacao plantations were abundantly nodulated. Acetylene reduction assays showed no, or very little, nitrogenase activity of roots from primary or secondary forest on clayey latosol near Manaus. Nodulated roots from secondary forest on sandy latosol showed acetylene-reducing activity. High rates of acetylene reduction were observed in nodulated roots of primary forest on alluvial ''varzea'' soil. Root samples showed ethylene absorption in controls without acetylene which might interfere with the results of acetylene reduction tests. The incidence of Azospirillum was also higher in black earth than the other soils examined, and in soils with higher pH. The hypothesis that Azospirillum is associated with Trema micantha roots was refuted. Roots and soils collected under cultivated grasses showed a higher incidence of Azospirillum when fertilized with phosphorus and lime. Results indicate that nitrogen fixation did occur in association with roots in some soils, but not with roots of primary or secondary forest on clayey latosol in the vicinity of Manaus, which is the most common soil in Central Amazonia. The possible reasons for this are discussed.

  15. Characterization of root-nodulating bacteria associated to Prosopis farcta growing in the arid regions of Tunisia.

    Science.gov (United States)

    Fterich, A; Mahdhi, M; Caviedes, M A; Pajuelo, E; Rivas, R; Rodriguez-Llorente, I D; Mars, M

    2011-06-01

    Diversity of 50 bacterial isolates recovered from root nodules of Prosopis farcta grown in different arid soils in Tunisia, was investigated. Characterization of isolates was assessed using a polyphasic approach including phenotypic characteristics, 16S rRNA gene PCR--RFLP and sequencing, nodA gene sequencing and MLSA. It was found that most of isolates are tolerant to high temperature (40°C) and salinity (3%). Genetic characterization emphasizes that isolates were assigned to the genus Ensifer (80%), Mesorhizobium (4%) and non-nodulating endophytic bacteria (16%). Forty isolates belonging to the genus Ensifer were affiliated to Ensifer meliloti, Ensifer xinjiangense/Ensifer fredii and Ensifer numidicus species. Two isolates belonged to the genus Mesorhizobium. Eight isolates failing to renodulate their host plant were endophytic bacteria and belonged to Bacillus, Paenibacillus and Acinetobacter genera. Symbiotic properties of nodulating isolates showed a diversity in their capacity to infect their host plant and fix atmospheric nitrogen. Isolate PG29 identified as Ensifer meliloti was the most effective one. Ability of Prosopis farcta to establish symbiosis with rhizobial species confers an important advantage for this species to be used in reforestation programs. This study offered the first systematic information about the diversity of microsymbionts nodulating Prosopis farcta in the arid regions of Tunisia.

  16. Drought stress provokes the down-regulation of methionine and ethylene biosynthesis pathways in Medicago truncatula roots and nodules.

    Science.gov (United States)

    Larrainzar, Estíbaliz; Molenaar, Johanna A; Wienkoop, Stefanie; Gil-Quintana, Erena; Alibert, Bénédicte; Limami, Anis M; Arrese-Igor, Cesar; González, Esther M

    2014-09-01

    Symbiotic nitrogen fixation is one of the first physiological processes inhibited in legume plants under water-deficit conditions. Despite the progress made in the last decades, the molecular mechanisms behind this regulation are not fully understood yet. Recent proteomic work carried out in the model legume Medicago truncatula provided the first indications of a possible involvement of nodule methionine (Met) biosynthesis and related pathways in response to water-deficit conditions. To better understand this involvement, the drought-induced changes in expression and content of enzymes involved in the biosynthesis of Met, S-adenosyl-L-methionine (SAM) and ethylene in M. truncatula root and nodules were analyzed using targeted approaches. Nitrogen-fixing plants were subjected to a progressive water deficit and a subsequent recovery period. Besides the physiological characterization of the plants, the content of total sulphur, sulphate and main S-containing metabolites was measured. Results presented here show that S availability is not a limiting factor in the drought-induced decline of nitrogen fixation rates in M. truncatula plants and provide evidences for a down-regulation of the Met and ethylene biosynthesis pathways in roots and nodules in response to water-deficit conditions. © 2014 John Wiley & Sons Ltd.

  17. Azorhizobium caulinodans Transmembrane Chemoreceptor TlpA1 Involved in Host Colonization and Nodulation on Roots and Stems

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2017-07-01

    Full Text Available Azorhizobium caulinodans ORS571 is a motile soil bacterium that interacts symbiotically with legume host Sesbania rostrata, forming nitrogen-fixing root and stem nodules. Bacterial chemotaxis plays an important role in establishing this symbiotic relationship. To determine the contribution of chemotaxis to symbiosis in A. caulinodans ORS571-S. rostrata, we characterized the function of TlpA1 (transducer-like protein in A. caulinodans, a chemoreceptor predicted by SMART (Simple Modular Architecture Research Tool, containing two N-terminal transmembrane regions. The tlpA1 gene is located immediately upstream of the unique che gene cluster and is transcriptionally co-oriented. We found that a ΔtlpA1 mutant is severely impaired for chemotaxis to various organic acids, glycerol and proline. Furthermore, biofilm forming ability of the strain carrying the mutation is reduced under certain growth conditions. Interestingly, competitive colonization ability on S. rostrata root surfaces is impaired in the ΔtlpA1 mutant, suggesting that chemotaxis of the A. caulinodans ORS571 contributes to root colonization. We also found that TlpA1 promotes competitive nodulation not only on roots but also on stems of S. rostrata. Taken together, our data strongly suggest that TlpA1 is a transmembrane chemoreceptor involved in A. caulinodans-S. rostrata symbiosis.

  18. Rhizobium acidisoli sp. nov., isolated from root nodules of Phaseolus vulgaris in acid soils.

    Science.gov (United States)

    Román-Ponce, Brenda; Jing Zhang, Yu; Soledad Vásquez-Murrieta, María; Hua Sui, Xin; Feng Chen, Wen; Carlos Alberto Padilla, Juan; Wu Guo, Xian; Lian Gao, Jun; Yan, Jun; Hong Wei, Ge; Tao Wang, En

    2016-01-01

    Two Gram-negative, aerobic, non-motile, rod-shaped bacterial strains, FH13T and FH23, representing a novel group of Rhizobium isolated from root nodules of Phaseolus vulgaris in Mexico, were studied by a polyphasic analysis. Phylogeny of 16S rRNA gene sequences revealed them to be members of the genus Rhizobium related most closely to 'Rhizobium anhuiense' CCBAU 23252 (99.7 % similarity), Rhizobium leguminosarum USDA 2370T (98.6 %), and Rhizobium sophorae CCBAU 03386T and others ( ≤ 98.3 %). In sequence analyses of the housekeeping genes recA, glnII and atpD, both strains formed a subclade distinct from all defined species of the genus Rhizobium at sequence similarities of 82.3-94.0 %, demonstrating that they represented a novel genomic species in the genus Rhizobium. Mean levels of DNA-DNA relatedness between the reference strain FH13T and the type strains of related species varied between 13.0 ± 2.0 and 52.1 ± 1.2 %. The DNA G+C content of strain FH13T was 63.5 mol% (Tm). The major cellular fatty acids were 16 : 0, 17 : 0 anteiso, 18 : 0, summed feature 2 (12 : 0 aldehyde/unknown 10.928) and summed feature 8 (18 : 1ω7c). The fatty acid 17 : 1ω5c was unique for this strain. Some phenotypic features, such as failure to utilize adonitol, l-arabinose, d-fructose and d-fucose, and ability to utilize d-galacturonic acid and itaconic acid as carbon source, could also be used to distinguish strain FH13T from the type strains of related species. Based upon these results, a novel species, Rhizobium acidisoli sp. nov., is proposed, with FH13T ( = CCBAU 101094T = HAMBI 3626T = LMG 28672T) as the type strain.

  19. Stress tolerance, genetic analysis and symbiotic properties of root-nodulating bacteria isolated from Mediterranean leguminous shrubs in Central Spain.

    Science.gov (United States)

    Ruiz-Díez, Beatriz; Fajardo, Susana; Puertas-Mejía, Miguel Angel; de Felipe, María del Rosario; Fernández-Pascual, Mercedes

    2009-01-01

    Nine root-nodulating bacterial isolates were obtained from the leguminous shrubs Spartium junceum, Adenocarpus hispanicus, Cytisus purgans, Cytisus laburnuum, Retama sphaerocarpa and Colutea arborescens in areas of Central Spain. A poliphasic approach analyzing phenotypic, symbiotic and genetic properties was used to study their diversity and characterize them in relation to Mediterranean conditions. Stress tolerance assays revealed marked variations in salinity, extreme pH and cadmium tolerance compared with reference strains, with the majority showing salinity, alkalinity and Cd tolerance and three of them growing at acid pH. Variation within the 16S rRNA gene was examined by amplified 16S rDNA restriction analysis (ARDRA) and direct sequencing to show genetic diversity. Phylogeny confirmed the close relationship of four isolates with Bradyrhizobium canariense, three with Phylobacterium myrsinacearum, one with Rhizobium rhizogenes and another with Mesorhizobium huakuii. The cross inoculation tests revealed wide spectra of nodulation. This is the first report of P. myrsinacearum being able to nodulate these leguminous shrubs, and also the first time reported the association between B.canariense, R. rhizogenes and M. huakuii and C. laburnuum, C. purgans and C. arborescens, respectively. These results suggested that native rhizobia could be suitable candidates as biofertilizers and/or inoculants of leguminous shrubs with restoration or revegetation purposes in Mediterranean areas.

  20. Erosion of Brassica incana Genetic Resources: Causes and Effects

    Science.gov (United States)

    Muscolo, A.; Settineri, G.; Mallamaci, C.; Papalia, T.; Sidari, M.

    2017-07-01

    Brassica incana Ten., possessing a number of useful agronomic traits, represents a precious genetic resource to be used in plant breeding programs to broaden the genetic base in most Brassica crop species. B. incana that grows on limestone cliffs is at risk of genetic erosion for environmental constraints and human activities. We studied the pedological conditions of a Calabrian site where the B. incana grows, and we correlated the soil properties to the physiological and biochemical aspects of B. incana to identify the causes and effects of the genetic erosion of this species. Our results evidenced that physical soil conditions did not affect B. incana growth and nutraceutical properties; conversely, biological soil properties modified its properties. We identified leaf pigments and secondary metabolites that can be used routinely as early warning indicators of plant threat, to evaluate in a short term the dynamic behavior of plants leading to species extinction.

  1. Molecular aspects of the nitrogen fixing system in pea root nodules

    International Nuclear Information System (INIS)

    Bisseling, T.

    1980-01-01

    The author considers symbiotic nitrogen fixation of Pisum sativum and Rhizobium leguminosarum. Some general aspects of nodule formation and the regulation of the proteins nitrogenase and leghemoglobin (Lb) have been studied. Synthesis of these proteins was studied by 35 SO 4 labelling of intact pea plants. The sequence of appearance of the proteins was determined with specific radioimmunoassays for each protein. (Auth.)

  2. Occurrence, structure, and nitrogen-fixation of root nodules of actinorhizal Arizona alder

    Science.gov (United States)

    J. O. Dawson; Gerald J. Gottfried; D. Hahn

    2005-01-01

    Actinorhizal plants are nodulated by the symbiotic, nitrogen-fixing actinomycete Frankia. The genus Alnus in the family Betulaceae is one of the 24 genera in 8 families of angiospermous plants that are actinorhizal. Arizona alder (Alnus oblongifolia Torr.) occurs in isolated populations associated with the watersheds of Madrean Sky Islands in the...

  3. CYTOKININ OXIDASE/DEHYDROGENASE3 Maintains Cytokinin Homeostasis during Root and Nodule Development in Lotus japonicus

    Czech Academy of Sciences Publication Activity Database

    Reid, D.E.; Heckmann, A.B.; Novák, Ondřej; Kelly, S.; Stougaard, J.

    2016-01-01

    Roč. 170, č. 2 (2016), s. 1060-1074 ISSN 0032-0889 R&D Projects: GA MŠk LK21306 Institutional support: RVO:61389030 Keywords : DEPENDENT PROTEIN-KINASE * NODULATION SIGNALING PATHWAY * SYMBIOTIC ORGAN DEVELOPMENT Subject RIV: EF - Botanics Impact factor: 6.456, year: 2016

  4. Novel Rhizobium lineages isolated from root nodules of the common bean (Phaseolus vulgaris L.) in Andean and Mesoamerican areas.

    Science.gov (United States)

    Ribeiro, Renan Augusto; Ormeño-Orrillo, Ernesto; Dall'Agnol, Rebeca Fuzinatto; Graham, Peter H; Martinez-Romero, Esperanza; Hungria, Mariangela

    2013-09-01

    The taxonomic affiliations of nineteen root-nodule bacteria isolated from the common bean (Phaseolus vulgaris L.) in Mexico, Ecuador and Brazil were investigated by analyses of 16S rRNA and of four protein-coding housekeeping genes. One strain from Mexico could be assigned to Rhizobium etli and two from Brazil to Rhizobium leucaenae, whereas another from Mexico corresponded to a recently described bean-nodulating species-level lineage related to R. etli and Rhizobium phaseoli. Ten strains isolated in Ecuador and Mexico corresponded to three novel Rhizobium lineages that fall into the R. phaseoli/R. etli/Rhizobium leguminosarum clade. One of those lineages, with representatives isolated mostly from Ecuador, seems to be dominant in beans from that Andean region. Only one of the Mexican strains clustered within the Rhizobium tropici clade, but as an independent lineage. Interestingly, four strains were affiliated with species within the Rhizobium radiobacter clade. The existence of yet non-described native Rhizobium lineages in both the Andean and Mesoamerican areas is discussed in relation to common-bean diversity and environmental conditions. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  5. Sucrose synthase and enolase expression in actinorhizal nodules of Alnus glutinosa: comparison with legume nodules.

    NARCIS (Netherlands)

    Ghelue, van M.; Ribeiro, A.; Solheim, B.; Akkermans, A.D.L.; Bisseling, T.; Pawlowski, K.

    1996-01-01

    Abstract Two different types of nitrogen-fixing root nodules are known - actinorhizal nodules induced by Frankia and legume nodules induced by rhizobia. While legume nodules show a stem-like structure with peripheral vascular bundles, actinorhizal nodule lobes resemble modified lateral roots with a

  6. Knock Down of Cell Division Cycle 16 Reveals an Inverse Relationship Between Lateral Root and Nodule Numbers and a Link to Auxin in Medicago truncatula

    Science.gov (United States)

    The post-embryonic development of lateral roots and nodules is a highly regulated process. Recent studies suggest the existence of cross talk and interdependency in the growth of these two organs. Although plant hormones including auxin and cytokinin appear to be key players in coordinating this cro...

  7. Identification of a transport mechanism for NH4+ in the symbiosome membrane of pea root nodules

    DEFF Research Database (Denmark)

    Mouritzen, P.; Rosendahl, L.

    1997-01-01

    Symbiosome membrane vesicles, facing bacteroid-side-out, were purified from pea (Pisum sativum L.) root nodules and used to study NH4+ transport across the membrane by recording vesicle uptake of the NH4+ analog [C-14]methylamine (MA). Membrane potentials (Delta psi) were imposed on the vesicles ...

  8. Complete Genome Sequence of Micromonospora Strain L5, a Potential Plant-Growth-Regulating Actinomycete, Originally Isolated from Casuarina equisetifolia Root Nodules

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, A. M.; Alvarado, J.; Bruce, D.; Chertkov, O.; De Hoff, P. L.; Detter, J. C.; Fujishige, N. A.; Goodwin, L. A.; Han, J.; Han, S.; Ivanova, N.; Land, M. L.; Lum, M. R.; Milani-Nejad, N.; Nolan, M.; Pati, A.; Pitluck, S.; Tran, S. S.; Woyke, T.; Valdes, M.

    2013-08-29

    Micromonospora species live in diverse environments and exhibit a broad range of functions including antibiotic production, biocontrol, and ability to degrade complex polysaccharides. To learn more about these versatile actinomycetes, we sequenced the genome of strain L5, originally isolated from root nodules of an actinorhizal plant growing in Mexico.

  9. Proteomic insights into intra- and intercellular plant-bacteria symbiotic association during root nodule formation

    Directory of Open Access Journals (Sweden)

    Afshin eSalavati

    2013-02-01

    Full Text Available Over the last several decades, there have been a large number of studies done on the all aspects of legumes and bacteria which participate in nitrogen-fixing symbiosis. The analysis of legume-bacteria interaction is not just a matter of numerical complexity in terms of variants of gene products that can arise from a single gene. Bacteria regulate their quorum-sensing genes to enhance their ability to induce conjugation of plasmids and symbiotic islands, and various protein secretion mechanisms; that can stimulate a collection of chain reactions including species-specific combinations of plant-secretion isoflavonoids, complicated calcium signaling pathways and autoregulation of nodulation mechanisms. Quorum-sensing systems are introduced by the intra- and intercellular organization of gene products lead to protein–protein interactions or targeting of proteins to specific cellular structures. In this study, an attempt has been made to review significant contributions related to nodule formation and development and their impacts on cell proteome for better understanding of plant-bacterium interaction mechanism at protein level. This review would not only provide new insights into the plant-bacteria symbiosis response mechanisms but would also highlights the importance of studying changes in protein abundance inside and outside of cells in response to symbiosis. Furthermore, the application to agriculture programe of plant-bacteria interaction will be discussed.

  10. [Studies on some phenolic compounds in Matthiola incana].

    Science.gov (United States)

    Ritter-Thomas, U

    1973-09-01

    1-Sinapoylglucose was isolated in cristalline form from mutants of Matthiola incana. In addition, 1-feruloyl-glucose and 1-p-cumaroyl-glucose were isolated and identified by paper chromatography. The molecular weights of penta-(trimethylsilyl)-1-sinapoyl-glucose and penta-(trimethylsilyl)-1-feruloyl-glucose have been determined by mass-spectroscopy.Two additionally isolated flavonol glycosides from Matthiola incana have been found to be kaempferol-7-rhamnoside-3-(rhamnosylarabinoside) and kaempferol-7-rhamnoside-3-(rhamnosylglucoside).

  11. Plant regeneration from mesophyll protoplasts of Matthiola incana (L.) R. Br.

    Science.gov (United States)

    Siemens, J; Sacristán, M D

    1995-04-01

    A protocol for obtaining regenerated fertile plants from mesophyll protoplasts of three lines of Matthiola incana is described. Protoplasts were isolated from leaves of 21-28 days old Matthiola plants grown in controlled environment. Sustained divisions were achieved when protoplasts were embedded in sodium alginate. Up to 2.0 % of the protoplasts developed into colonies which could be transferred to shoot regeneration media. More than 25 % of the obtained calluses regenerated shoots. About 4 % of these shoots could be rooted and after transfer to soil phenotypically normal plants have been obtained.

  12. A Novel Sucrose-Regulatory MADS-Box Transcription Factor GmNMHC5 Promotes Root Development and Nodulation in Soybean (Glycine max [L.] Merr.).

    Science.gov (United States)

    Liu, Wei; Han, Xiangdong; Zhan, Ge; Zhao, Zhenfang; Feng, Yongjun; Wu, Cunxiang

    2015-08-31

    The MADS-box protein family includes many transcription factors that have a conserved DNA-binding MADS-box domain. The proteins in this family were originally recognized to play prominent roles in floral development. Recent findings, especially with regard to the regulatory roles of the AGL17 subfamily in root development, have greatly broadened their known functions. In this study, a gene from soybean (Glycine max [L.] Merr.), GmNMHC5, was cloned from the Zigongdongdou cultivar and identified as a member of the AGL17 subfamily. Real-time fluorescence quantitative PCR analysis showed that GmNMHC5 was expressed at much higher levels in roots and nodules than in other organs. The activation of expression was first examined in leaves and roots, followed by shoot apexes. GmNMHC5 expression levels rose sharply when the plants were treated under short-day conditions (SD) and started to pod, whereas low levels were maintained in non-podding plants under long-day conditions (LD). Furthermore, overexpression of GmNMHC5 in transgenic soybean significantly promoted lateral root development and nodule building. Moreover, GmNMHC5 is upregulated by exogenous sucrose. These results indicate that GmNMHC5 can sense the sucrose signal and plays significant roles in lateral root development and nodule building.

  13. A Novel Sucrose-Regulatory MADS-Box Transcription Factor GmNMHC5 Promotes Root Development and Nodulation in Soybean (Glycine max [L.] Merr.

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2015-08-01

    Full Text Available The MADS-box protein family includes many transcription factors that have a conserved DNA-binding MADS-box domain. The proteins in this family were originally recognized to play prominent roles in floral development. Recent findings, especially with regard to the regulatory roles of the AGL17 subfamily in root development, have greatly broadened their known functions. In this study, a gene from soybean (Glycine max [L.] Merr., GmNMHC5, was cloned from the Zigongdongdou cultivar and identified as a member of the AGL17 subfamily. Real-time fluorescence quantitative PCR analysis showed that GmNMHC5 was expressed at much higher levels in roots and nodules than in other organs. The activation of expression was first examined in leaves and roots, followed by shoot apexes. GmNMHC5 expression levels rose sharply when the plants were treated under short-day conditions (SD and started to pod, whereas low levels were maintained in non-podding plants under long-day conditions (LD. Furthermore, overexpression of GmNMHC5 in transgenic soybean significantly promoted lateral root development and nodule building. Moreover, GmNMHC5 is upregulated by exogenous sucrose. These results indicate that GmNMHC5 can sense the sucrose signal and plays significant roles in lateral root development and nodule building.

  14. Characterization of the plant growth promoting bacterium, Enterobacter cloacae MSR1, isolated from roots of non-nodulating Medicago sativa.

    Science.gov (United States)

    Khalifa, Ashraf Y Z; Alsyeeh, Abdel-Moneium; Almalki, Mohammed A; Saleh, Farag A

    2016-01-01

    The aim of the present study was to characterize the endophytic bacterial strain designated MSR1 that was isolated from inside the non-nodulating roots of Medicago sativa after surface-sterilization. MSR1 was identified as Enterobacter cloacae using both 16S rDNA gene sequence analysis and API20E biochemical identification system (Biomerieux, France). Furthermore, this bacterium was characterized using API50CH kit (Biomerieux, France) and tested for antibacterial activities against some food borne pathogens. The results showed that E. cloacae consumed certain carbohydrates such as glycerol, d-xylose, d-maltose and esculin melibiose as a sole carbon source and certain amino acids such as arginine, tryptophan ornithine as nitrogen source. Furthermore, MSR1 possessed multiple plant-growth promoting characteristics; phosphate solubility, production of phytohormones acetoin and bioactive compounds. Inoculation of Pisum sativum with MSR1 significantly improved the growth parameters (the length and dry weight) of this economically important grain legume compared to the non-treated plants. To our knowledge, this is the first report addressing E. cloacae which exist in roots of alfalfa growing in Al-Ahsaa region. The results confirmed that E. cloacae exhibited traits for plant growth promoting and could be developed as an eco-friendly biofertilizer for P. sativum and probably for other important plant species in future.

  15. Bradyrhizobium namibiense sp. nov., a symbiotic nitrogen-fixing bacterium from root nodules of Lablab purpureus, hyacinth bean, in Namibia.

    Science.gov (United States)

    Grönemeyer, Jann Lasse; Bünger, Wiebke; Reinhold-Hurek, Barbara

    2017-10-16

    Four strains of symbiotic bacteria from root nodules of hyacinth bean (Lablab purpureus (L.) Sweet) from Namibia were previously identified as a novel group within the genus Bradyrhizobium. To confirm their taxonomic status, these strains were further characterized by taking a polyphasic approach. The type strain possessed 16S rRNA gene sequences identical to Bradyrhizobium paxllaeri LMTR 21 T and Bradyrhizobiumicense LMTR 13 T , the full-length sequences were identical to those retrieved from SAMN05230119 and SAMN05230120, respectively. However, the intergenic spacer sequences of the novel group showed identities of less than 93.1 % to described Bradyrhizobium species and were placed in a well-supported separate lineage in the phylogenetic tree. Phylogenetic analyses of six concatenated housekeeping genes, recA, glnII, gyrB, dnaK, atpD and rpoB, corroborated that the novel strains belonged to a lineage distinct from named species of the genus Bradyrhizobium, with highest sequence identities to Bradyrhizobiumjicamae and B. paxllaeri (below 93 %). The species status was validated by results of DNA-DNA hybridization and average nucleotide identity values of genome sequences. The combination of phenotypic characteristics from several tests, including carbon source utilization and antibiotic resistance, could be used to differentiate representative strains from recognized species of the genus Bradyrhizobium. Phylogenetic analysis of nodC and nifH genes placed the novel strains in a group with B. paxllaeri and B.lablabi. Novel strain 5-10 T induces effective nodules on Lablab purpureus, Vigna subterranea, Vigna unguiculata and Arachis hypogaea. Based on our results, we conclude that our strains represent a novel species for which the name Bradyrhizobium namibiense sp. nov. is proposed, with type strain 5-10 T [LMG 28789, DSM 100300, NTCCM0017 (Windhoek)].

  16. Bradyrhizobium kavangense sp. nov., a symbiotic nitrogen-fixing bacterium from root nodules of traditional Namibian pulses.

    Science.gov (United States)

    Lasse Grönemeyer, Jann; Hurek, T; Reinhold-Hurek, Barbara

    2015-12-01

    Eight strains of symbiotic bacteria from root nodules of local races of cowpea (Vigna unguiculata) and Bambara groundnut (Vigna subterranea) grown on subsistence farmers' fields in the Kavango region, Namibia, were previously characterized and identified as a novel group within the genus Bradyrhizobium. To clarify their taxonomic status, these strains were further characterized using a polyphasic approach. In phylogenetic analysis of the 16S rRNA gene sequence the novel group was most closely related to Bradyrhizobium iriomotense EK05T and Bradyrhizobium ingae BR 10250T, and to 'Bradyrhizobium arachidis' CCBAU 051107 in the ITS sequence analysis. Phylogenetic analysis of concatenated glnII-recA-rpoB-dnaK sequences placed the strains in a lineage distinct from named species of the genus Bradyrhizobium. The species status was validated by results of DNA-DNA hybridization. Phylogenetic analysis of nifH and nodC genes placed the novel strains in a group with 'B. arachidis' CCBAU 051107. The combination of phenotypic characteristics from several tests including carbon source utilization and antibiotic resistance could be used to differentiate representative strains from recognized species of the genus Bradyrhizobium. Novel strain 14-3T induces effective nodules on Vigna subterranea, Vigna unguiculata, Arachis hypogaea and Lablab purpureus. Based on the data presented, it is concluded that the strains represent a novel species of the genus Bradyrhizobium, for which the name Bradyrhizobium kavangense sp. nov. is proposed. The type strain is 14-3T [ = DSM 100299T = LMG 28790T = NTCCM 0012T (Windhoek)]. The DNA G+C content of strain 14-3T is 63.8 mol% (Tm).

  17. Towards a better understanding of the role of reactive oxygen species in legume root nodules

    NARCIS (Netherlands)

    Ramos Escribano, J.

    2004-01-01

    Biological N2 fixation is carried out exclusively by prokaryotes, either in the free-living form or in mutualistic symbioses with green algae, legumes and actinorhizal plants. The most agronomica1ly relevant symbiosis is, by fàr, that formed between soil rhizobia and legume roots. In addition, the

  18. A nonsymbiotic root hair tip growth phenotype in NORK-mutated legumes: implications for nodulation factor-induced signaling and formation of a multifaceted root hair pocket for bacteria

    NARCIS (Netherlands)

    Esseling, J.J.; Lhuissier, F.G.P.; Emons, A.M.C.

    2004-01-01

    The Medicago truncatula Does not Make Infections (DMI2) mutant is mutated in the nodulation receptor-like kinase, NORK. Here, we report that NORK-mutated legumes of three species show an enhanced touch response to experimental handling, which results in a nonsymbiotic root hair phenotype. When care

  19. Molecular cloning of the cDNA encoding aspartate aminotransferase from bean root nodules and determination of its role in nodule nitrogen metabolism.

    Science.gov (United States)

    Silvente, Sonia; Camas, Alberto; Lara, Miguel

    2003-06-01

    A cDNA clone encoding aspartate aminotransferase (PVAAT-2) (EC 2.6.1.1) was isolated from the common bean Phaseolus vulgaris nodule cDNA library. The nucleotide sequence analysis of the full-length cDNA allowed its identification by comparison with sequence databases. The amino acid sequence of the bean PvAAT-2 showed high similarity with the AAT-2 isoforms described in other leguminous plants. The amino-terminal region of the PvAAT-2 contains a sequence, which shares common features of plastid transit peptides. Southern blot analysis showed that the PvAAT-2 clone is encoded by a single gene in the P. vulgaris genome. Analysis of the PvAAT-2 mRNA levels suggests that the expression of this gene is nodule enhanced. The PvAAT-2 transcript is more abundant in nodules with increased synthesis of amides and is down-regulated in conditions where ureides accumulate. When plants were supplemented with ureides or with amides, PvAAT-2 expression was reduced, while it was not affected when plants were treated with allopurinol, an inhibitor of ureide synthesis. On the other hand, the expression of asparagine synthetase (another enzyme involved in the synthesis of amides) is not affected either by ureides or amides. These data suggest a role for AAT-2 in the mechanism involved in the synthesis of nitrogen compounds in bean nodules.

  20. Microvirga ossetica sp. nov., a species of rhizobia isolated from root nodules of the legume species Vicia alpestris Steven.

    Science.gov (United States)

    Safronova, Vera I; Kuznetsova, Irina G; Sazanova, Anna L; Belimov, Andrey A; Andronov, Evgeny E; Chirak, Elizaveta R; Osledkin, Yuri S; Onishchuk, Olga P; Kurchak, Oksana N; Shaposhnikov, Alexander I; Willems, Anne; Tikhonovich, Igor A

    2017-01-01

    Gram-stain-negative strains V5/3MT, V5/5K, V5/5M and V5/13 were isolated from root nodules of Vicia alpestris plants growing in the North Ossetia region (Caucasus). Sequencing of the partial 16S rRNA gene (rrs) and four housekeeping genes (dnaK, gyrB, recA and rpoB) showed that the isolates from V. alpestris were most closely related to the species Microvirga zambiensis (order Rhizobiales, family Methylobacteriaceae) which was described for the single isolate from root nodule of Listia angolensis growing in Zambia. Sequence similarities between the Microvirga-related isolates and M. zambiensis WSM3693T ranged from 98.5 to 98.7 % for rrs and from 79.7 to 95.8 % for housekeeping genes. Cellular fatty acids of the isolates V5/3MT, V5/5K, V5/5M and V5/13 included important amounts of C18 : 1ω7c (54.0-67.2 %), C16 : 0 (6.0-7.8 %), C19 : 0 cyclo ω8c (3.1-10.2 %), summed feature 2 (comprising one or more of iso-C16 : 1 I, C14 : 0 3-OH and unknown ECL 10.938, 5.8-22.5 %) and summed feature 3 (comprising C16 : 1ω7c and/or iso-C15 : 02-OH, 2.9-4.0 %). DNA-DNA hybridization between the isolate V5/3MT and M. zambiensis WSM3693T revealed DNA-DNA relatedness of 35.3 %. Analysis of morphological and physiological features of the novel isolates demonstrated their unique phenotypic profile in comparison with reference strains from closely related species of the genus Microvirga. On the basis of genotypic and phenotypic analysis, a novel species named Microvirga ossetica sp. nov. is proposed. The type strain is V5/3MT (=LMG 29787T=RCAM 02728T). Three additional strains of the species are V5/5K, V5/5M and V5/13.

  1. Agrobacterium salinitolerans sp. nov., a saline-alkaline-tolerant bacterium isolated from root nodule of Sesbania cannabina.

    Science.gov (United States)

    Yan, Jun; Li, Yan; Yan, Hui; Chen, Wen Feng; Zhang, Xiaoxia; Wang, En Tao; Han, Xiao Zeng; Xie, Zhi Hong

    2017-06-01

    Two Gram-staining-negative, aerobic bacteria (YIC 5082T and YIC4104) isolated from root nodules of Sesbania cannabina grown in a high-salt and alkaline environment were identified as a group in the genus Agrobacterium because they shared 100 and 99.7 % sequence similarities of 16S rRNA and recA+atpD genes, respectively. These two strains showed 99.2/100 % and 93.9/95.4 % 16S rRNA and recA+atpD gene sequence similarities to Agrobacterium radiobacter LMG140T and Agrobacterium. pusense NRCPB10T, respectively. The average nucleotide identities (ANI) of genome sequences were 89.95 % or lower between YIC 5082T and the species of the genus Agrobacterium examined. Moreover, these two test strains formed a unique nifH lineage deeply separated from other rhizobia. Although the nodC gene was not detected in YIC 5082T and YIC4104, they could form effective root nodules on S. cannabina plants. The main cellular fatty acids in YIC 5082T were summed feature 8 (C18 : 1ω7c/C18 : 1ω6c), C19 : 0cyclo ω8c, summed feature 2 (C12 : 0 aldehyde/unknown equivalent chain length 10.9525) and C16 : 0. The DNA G+C content of YIC 5082T was 59.3 mol%. The failure to utilize d-sorbitol as a carbon source distinguished YIC 5082T from the type strains of related species. YIC 5082T could grow in presence of 5.0 % (w/v) NaCl and at a pH of up to 10.0. Based on results regarding the genetic and phenotypic properties of YIC 5082T and YIC4104 the name Agrobacterium salinitolerans sp. nov. is proposed and YIC 5082T (=HAMBI 3646T=LMG 29287T) is designed as the type strain.

  2. Preparation of Artificial Blood from the Extract of Legume Root Nodules, and the Creation of Artificial Latent Fingermarks in Blood Using Artificial Blood.

    Science.gov (United States)

    Hong, Sungwook; Kim, Chaewon; Jeon, Soyoung; Lee, Eunhye

    2018-01-01

    Distribution of homogeneous fingermarks in blood is essential for conducting proficiency tests in forensic science. Hence, the artificial blood was prepared using the root nodule extract of Glycine max plants. The reactivity of the artificial blood with widely used human blood detection reagents was tested. Artificial latent fingermarks in blood were printed using an inkjet cartridge case filled with artificial blood solution. The artificial latent fingermarks in blood were developed with amino acid-sensitive reagents and could obtain development as prominent as the image of the master fingermark saved on the computer. Therefore, it has been confirmed that the extract of legume root nodules can be used as artificial blood, and the artificial blood can be used for the preparation of artificial latent fingermarks or footmarks in blood. © 2017 American Academy of Forensic Sciences.

  3. Rhizobium hedysari sp. nov., a novel species isolated from a root nodule of Hedysarum multijugum in China.

    Science.gov (United States)

    Xu, Lin; Shi, Jianfeng; Li, Caixia; Zhu, Shengan; Li, Bo

    2017-04-01

    A strain 5-1-2 T was isolated from a root nodule of Hedysarum multijugum collected from Zhangye city, Gansu province, north-west China. Phylogenetic analysis based on the 16S rRNA gene sequence and other housekeeping genes (recA and atpD) indicated that the strain represents a novel species in the genus Rhizobium close to the strain Rhizobium subbaraonis JC85 T with similarities of 98.27, 88.92 and 89.62%, respectively. Strain 5-1-2 T contained Q-10 as the predominant ubiquinone. Our results showed that the major fatty acids were feature 8 (C 18:1 ω7c and/or C 18:1 ω6c; 38.90%). In addition, the DNA-DNA hybridizations with the type strains R. subbaraonis JC85 T and Rhizobium halophytocola YC6881 T were 39.2 ± 2.1 and 44.3 ± 1.9, respectively. Therefore, a novel species Rhizobium hedysari sp. nov. is proposed, and 5-1-2 T (=CGMCC1.15677 T  = NBRC112532 T) is designated as the type strain.

  4. Rhizobium qilianshanense sp. nov., a novel species isolated from root nodule of Oxytropis ochrocephala Bunge in China.

    Science.gov (United States)

    Xu, Lin; Zhang, Yong; Deng, Zheng Shan; Zhao, Liang; Wei, Xiu Li; Wei, Ge Hong

    2013-03-01

    During a study of the diversity and phylogeny of rhizobia isolated from root nodules of Oxytropis ochrocephala grown in the northwest of China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. These strains have identical 16S rRNA gene sequences, which showed a mean similarity of 94.4 % with the most closely related species, Rhizobium oryzae. Analysis of recA and glnA sequences showed that these strains have less than 88.1 and 88.7 % similarity with the defined species of Rhizobium, respectively. The genetic diversity revealed by ERIC-PCR fingerprinting indicated that the isolates correspond to different strains. Strain CCNWQLS01(T) contains Q-10 as the predominant ubiquinone. The major fatty acids were identified as feature 8 (C18: 1ω7c and/or C18: 1ω6c; 67.2 %). Therefore, a novel species Rhizobium qilianshanense sp. nov. is proposed, and CCNWQLS01(T) (= ACCC 05747(T) = JCM 18337(T)) is designated as the type strain.

  5. Poly-β-hydroxybutyrate and exopolysaccharide biosynthesis by bacterial isolates from pigeonpea [Cajanus cajan (L.) Millsp] root nodules.

    Science.gov (United States)

    Fernandes, Paulo Ivan; de Oliveira, Paulo Jansen; Rumjanek, Norma Gouvêa; Xavier, Gustavo Ribeiro

    2011-02-01

    The bacterial strains that are able to produce biopolymers that are applied in industrial sectors present a source of renewable resources. Some microorganisms are already applied at several industrial sectors, but the prospecting of new microbes must bring microorganisms that are feasible to produce interesting biopolymers more efficiently and in cheaper conditions. Among the biopolymers applied industrially, polyhydroxybutyrate (PHB) and exopolysaccharides (EPS) stand out because of its applications, mainly in biodegradable plastic production and in food industry, respectively. In this context, the capacity of bacteria isolated from pigeonpea root nodules to produce EPS and PHB was evaluated, as well as the cultural characterization of these isolates. Among the 38 isolates evaluated, the majority presented fast growth and ability to acidify the culture media. Regarding the biopolymer production, five isolates produced more than 10 mg PHB per liter of culture medium. Six EPS producing bacteria achieved more than 200 mg EPS per liter of culture medium. Evaluating different carbon sources, the PHB productivity of the isolate 24.6b reached 69% of cell dry weight when cultured with starch as sole carbon source, and the isolate 8.1c synthesized 53% PHB in dry cell biomass and more than 1.3 g L⁻¹ of EPS when grown using xylose as sole carbon source.

  6. Paenibacillus medicaginis sp. nov. a chitinolytic endophyte isolated from the root nodule of alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Lai, Wei-An; Hameed, Asif; Lin, Shih-Yao; Hung, Mei-Hua; Hsu, Yi-Han; Liu, You-Cheng; Shahina, Mariyan; Shen, Fo-Ting; Young, Chiu-Chung

    2015-08-04

    A Gram-stain-variable, short-rod-shaped, endospore-forming, strictly aerobic, non-motile, chitinolytic and endophytic bacterium, designated strain CC-Alfalfa-19T, exhibiting unusual bipolar appendages was isolated from the root nodule of alfalfa (Medicago sativa L.) in Taiwan and subjected to a polyphasic taxonomy. Based on 16S rRNA gene sequence analysis, strain CC-Alfalfa-19T was found to be most closely related to Paenibacillus puldeungensis CAU 9324T (95.2 %), whereas other Paenibacillus species shared ≤95.0 % sequence similarity. The phylogenetic analysis revealed a distinct phyletic lineage established by strain CC-Alfalfa-19T with respect to other Paenibacillus species. Fatty acids comprised predominantly anteiso-C15:0, C16:0, anteiso-C17:0 and iso-C16. Menaquinone 7 (MK-7) was identified as the sole respiratory quinone and the genomic DNA G+C content was 42.7 mol%. Polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, an unidentified glycolipid and an unidentified lipid. The diagnostic diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. Based on the polyphasic taxonomic evidences that were in line with the genus Paenibacillus and additional distinguishing characteristics, strain CC-Alfalfa-19T is considered to represent a novel species, for which the name Paenibacillus medicaginis sp. nov. (type strain CC-Alfalfa-19T = BCRC 80441T = JCM 18446T) is proposed.

  7. Homeostasis in defined genotypes of Matthiola incana.

    Science.gov (United States)

    Seyffert, W

    1983-02-01

    Based on 256 defined genotypes of the Brassicaceae Matthiola incana the influence of the alleles at four different loci and of their combinations on homeostasis was investigated against an isogenic background. The measured character was the anthocyanin content of the flowers. There are significant maternal and paternal influences on homeostasis. Moreover the extent of heterozygosity as well as the number of wildtype alleles, summarized over all loci, are positively correlated with the increase of homeostasis. The analysis of individual gene effects shows distinct graduations between the contributions of the particular loci. In principle, the wild-type allele proved to be more homeostatic when compared to the mutant; in some cases monogenic heterosis was indicated. Nonallelic interactions of first and second order do considerably modify the degree of expression of homeostasis; they are neither strongly correlated with the individual gene effects nor with the interactions of lower order, and hence they are not predictable. This means also that it is not possible to formulate a general hypothesis as to the causes of homeostasis. We have to assume rather that homeostasis depends on specific gene combinations which enable the organism to stabilize its phenotype by means of certain physiological conditions.

  8. Rhizobium cauense sp. nov., isolated from root nodules of the herbaceous legume Kummerowia stipulacea grown in campus lawn soil.

    Science.gov (United States)

    Liu, Tian Yan; Li, Ying; Liu, Xiao Xiao; Sui, Xin Hua; Zhang, Xiao Xia; Wang, En Tao; Chen, Wen Xin; Chen, Wen Feng; Puławska, Joanna

    2012-10-01

    Three bacterial isolates (CCBAU 101002(T), CCBAU 101000 and CCBAU 101001) originating from root nodules of the herbaceous legume Kummerowia stipulacea grown in the campus lawn of China Agricultural University were characterized with a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence analysis showed that the isolates shared 99.85-99.92% sequence similarities and had the highest similarities to the type strains of Rhizobium mesoamericanum (99.31%), R. endophyticum (98.54%), R. tibeticum (98.38%) and R. grahamii (98.23%). Sequence similarity of four concatenated housekeeping genes (atpD, glnII, recA and rpoB) between CCBAU 101002(T) and its closest neighbor (R. grahamii) was 92.05%. DNA-DNA hybridization values between strain CCBAU 101002(T) and the four type strains of the most closely related Rhizobium species were less than 28.4±0.8%. The G+C mol% of the genomic DNA for strain CCBAU 101002(T) was 58.5% (Tm). The major respiratory quinone was ubiquinone (Q-10). Summed feature 8 (18:1ω7cis/18:1ω6cis) and 16:0 were the predominant fatty acids. Strain CCBAU 101002(T) contained phosphatidylcholine and phosphatidylethanolamine as major polar lipids, and phosphatidylglycerol and cardiolipin as minor ones. No glycolipid was detected. Unlike other strains, this novel species could utilize dulcite or sodium pyruvate as sole carbon sources and it was resistant to 2% (w/v) NaCl. On the basis of the polyphasic study, a new species Rhizobium cauense sp. nov. is proposed, with CCBAU 101002(T) (=LMG 26832(T)=HAMBI 3288(T)) as the type strain. Copyright © 2012 Elsevier GmbH. All rights reserved.

  9. Paenibacillus medicaginis sp. nov. a chitinolytic endophyte isolated from a root nodule of alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Lai, Wei-An; Hameed, Asif; Lin, Shih-Yao; Hung, Mei-Hua; Hsu, Yi-Han; Liu, You-Cheng; Shahina, Mariyan; Shen, Fo-Ting; Young, Chiu-Chung

    2015-11-01

    A Gram-stain-variable, short-rod-shaped, endospore-forming, strictly aerobic, non-motile, chitinolytic and endophytic bacterium, designated strain CC-Alfalfa-19T, exhibiting unusual bipolar appendages was isolated from a root nodule of alfalfa (Medicago sativa L.) in Taiwan and subjected to a polyphasic taxonomic study. Based on 16S rRNA gene sequence analysis, strain CC-Alfalfa-19T was found to be most closely related to Paenibacillus puldeungensis CAU 9324T (95.2 %), whereas other species of the genus Paenibacillus shared ≤ 95.0 % sequence similarity. The phylogenetic analysis revealed a distinct phyletic lineage established by strain CC-Alfalfa-19T with respect to other species of the genus Paenibacillus. Fatty acids comprised predominantly anteiso-C15 : 0, C16 : 0, anteiso-C17 : 0 and iso-C16 : 0. Menaquinone 7 (MK-7) was identified as the sole respiratory quinone and the genomic DNA G+C content was 42.7 mol%. Polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, an unidentified glycolipid and an unidentified lipid. The diagnostic diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. Based on the polyphasic taxonomic evidence that was in line with the genus Paenibacillus and additional distinguishing characteristics, strain CC-Alfalfa-19T is considered to represent a novel species, for which the name Paenibacillus medicaginis sp. nov. (type strain CC-Alfalfa-19T = BCRC 80441T = JCM 18446T) is proposed.

  10. Genetic variation in pea (Pisum sativum L.) demonstrates the importance of root but not shoot C/N ratios in the control of plant morphology and reveals a unique relationship between shoot length and nodulation intensity.

    Science.gov (United States)

    Ludidi, Ndiko N; Pellny, Till K; Kiddle, Guy; Dutilleul, Christelle; Groten, Karin; VAN Heerden, Philippus D R; Dutt, Som; Powers, Stephen J; Römer, Peter; Foyer, Christine H

    2007-10-01

    Nodule numbers are regulated through systemic auto-regulatory signals produced by shoots and roots. The relative effects of shoot and root genotype on nodule numbers together with relationships to organ biomass, carbon (C) and nitrogen (N) status, and related parameters were measured in pea (Pisum sativum) exploiting natural genetic variation in maturity and apparent nodulation intensity. Reciprocal grafting experiments between the early (Athos), intermediate (Phönix) and late (S00182) maturity phenotypes were performed and Pearson's correlation coefficients for the parameters were calculated. No significant correlations were found between shoot C/N ratios and plant morphology parameters, but the root C/N ratio showed a strong correlation with root fresh and dry weights as well as with shoot fresh weight with less significant interactions with leaf number. Hence, the root C/N ratio rather than shoot C/N had a predominant influence on plant morphology when pea plants are grown under conditions of symbiotic nitrogen supply. The only phenotypic characteristic that showed a statistically significant correlation with nodulation intensity was shoot length, which accounted for 68.5% of the variation. A strong linear relationship was demonstrated between shoot length and nodule numbers. Hence, pea nodule numbers are controlled by factors related to shoot extension, but not by shoot or root biomass accumulation, total C or total N. The relationship between shoot length and nodule numbers persisted under field conditions. These results suggest that stem height could be used as a breeding marker for the selection of pea cultivars with high nodule numbers and high seed N contents.

  11. Variation in the essential oil constituents of Pteronia incana ...

    African Journals Online (AJOL)

    The essential oil of Pteronia incana was collected and was investigated on a monthly basis using GCMS. The oil volume and its constituents vary greatly with different time of sampling and distillation. The oil contains a high percentage of myrcene a-pinene, b-pinene with sabinene, a-terpinene, 1.8 cineole and limonene.

  12. Genetically controlled anthocyanin synthesis in cell cultures of Matthiola incana.

    Science.gov (United States)

    Leweke, B; Forkmann, G

    1982-04-01

    Callus cultures were derived from different parts of 8 anthocyanin producing and 2 white flowering lines of the crucifer Matthiola incana. The tissue cultures of the cyanic lines were shown to produce genotype specific anthocyanin patterns, whereas in the calli of the acyanic lines no anthocyanin synthesis occured.

  13. Herbicidal activity of sulforaphene from stock (Matthiola incana).

    Science.gov (United States)

    Brinker, A M; Spencer, G F

    1993-10-01

    A herbicidal compound was isolated from extracts ofMatthiola incana and identified as sulforaphene (4-methylsulfinyl-3-butenyl isothiocyanate). The ED50 of this compound against velvetleaf seedlings was approximately 2×10(-4) M. Glucoraphenin, the glucosinolate that is the natural precursor of sulforaphene, was less phytotoxic, with an ED50 of near 6×10(-3)M.

  14. The monomeric GTPase RabA2 is required for progression and maintenance of membrane integrity of infection threads during root nodule symbiosis.

    Science.gov (United States)

    Dalla Via, Virginia; Traubenik, Soledad; Rivero, Claudio; Aguilar, O Mario; Zanetti, María Eugenia; Blanco, Flavio Antonio

    2017-04-01

    Progression of the infection canal that conducts rhizobia to the nodule primordium requires a functional Rab GTPase located in Golgi/trans-Golgi that also participate in root hair polar growth. Common bean (Phaseolus vulgaris) symbiotically associates with its partner Rhizobium etli, resulting in the formation of root nitrogen-fixing nodules. Compatible bacteria can reach cortical cells in a tightly regulated infection process, in which the specific recognition of signal molecules is a key step to select the symbiotic partner. In this work, we show that RabA2, a monomeric GTPase from common bean, is required for the progression of the infection canal, referred to as the infection thread (IT), toward the cortical cells. Expression of miss-regulated mutant variants of RabA2 resulted in an increased number of abortive infection events, including bursting of ITs and a reduction in the number of nodules. Nodules formed in these plants were small and contained infected cells with disrupted symbiosome membranes, indicating either early senescence of these cells or defects in the formation of the symbiosome membrane during bacterial release. RabA2 localized to mobile vesicles around the IT, but mutations that affect GTP hydrolysis or GTP/GDP exchange modified this localization. Colocalization of RabA2 with ArfA1 and a Golgi marker indicates that RabA2 localizes in Golgi stacks and the trans-Golgi network. Our results suggest that RabA2 is part of the vesicle transport events required to maintain the integrity of the membrane during IT progression.

  15. Differentially expressed genes in mycorrhized and nodulated roots of common bean are associated with defense, cell wall architecture, N metabolism, and P metabolism

    Science.gov (United States)

    Gómez, Brenda-Mariana; Blanco, Lourdes; Lara, Miguel

    2017-01-01

    Legumes participate in two important endosymbiotic associations, with phosphorus-acquiring arbuscular mycorrhiza (AM, soil fungi) and with nitrogen-fixing bacterial rhizobia. These divergent symbionts share a common symbiotic signal transduction pathway that facilitates the establishment of mycorrhization and nodulation in legumes. However, the unique and shared downstream genes essential for AM and nodule development have not been identified in crop legumes. Here, we used ion torrent next-generation sequencing to perform comparative transcriptomics of common bean (Phaseolus vulgaris) roots colonized by AM or rhizobia. We analyzed global gene expression profiles to identify unique and shared differentially expressed genes (DEGs) that regulate these two symbiotic interactions, and quantitatively compared DEG profiles. We identified 3,219 (1,959 upregulated and 1,260 downregulated) and 2,645 (1,247 upregulated and 1,398 downregulated) unigenes that were differentially expressed in response to mycorrhizal or rhizobial colonization, respectively, compared with uninoculated roots. We obtained quantitative expression profiles of unique and shared genes involved in processes related to defense, cell wall structure, N metabolism, and P metabolism in mycorrhized and nodulated roots. KEGG pathway analysis indicated that most genes involved in jasmonic acid and salicylic acid signaling, N metabolism, and inositol phosphate metabolism are variably expressed during symbiotic interactions. These combined data provide valuable information on symbiotic gene signaling networks that respond to mycorrhizal and rhizobial colonization, and serve as a guide for future genetic strategies to enhance P uptake and N-fixing capacity to increase the net yield of this valuable grain legume. PMID:28771548

  16. [Hydrogen peroxide content and catalase activity at inoculation with root tubercle bacteria of pea seedlings with the various nodulation ability].

    Science.gov (United States)

    Vasil'eva, G G; Glian'ko, A K; Mironova, N V

    2005-01-01

    Hydrogen peroxide (H2O2) content and catalase activity were studied in pea (Pisum sativum L.) seedlings with normal (cultivar Marat) and disrupted (pea mutants) process of nodulation, which were inoculated with the nitrogen-fixing bacterium Rhizobium leguminosarum strain CIAM 1026. Differences in hydrogen peroxide content and catalase activity in pea seedlings with different ability for nodulation, which were inoculated with rhizobia, were found. It was assumed that H2O2 and catalase are involved in defensive and regulatory mechanisms in the host plant.

  17. Formation of organelle-like N2-fixing symbiosomes in legume root nodules is controlled by DMI2

    NARCIS (Netherlands)

    Limpens, E.H.M.; Mirabella, R.; Fedorova, E.; Franken, C.; Franssen, H.; Bisseling, T.; Geurts, R.

    2005-01-01

    In most legume nodules, the N2-fixing rhizobia are present as organelle-like structures inside their host cells. These structures, named symbiosomes, contain one or a few rhizobia surrounded by a plant membrane. Symbiosome formation requires the release of bacteria from cell-wall-bound infection

  18. Crotalaria incana l. and leucaena leucocephala lam. (leguminosae): toxicity indicator species of petroleum hydrocarbons in soil; Crotalaria incana l. y leucaena leucocephala lam. (leguminosae): especies indicadoras de toxicidad por hidrocarburos de petroleo en el suelo

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez Luna, Dinora; Castellan Estrada, Mepivoseth; Rivera Cruz, Maria del C.; Ortiz Ceballos, Angel I.; Izquierdo R., Francisco [Colegio de Postgraduados, Campus Montecillo, Montecillo, Estado de Mexico (Mexico)]. E-mail: dinovaz@colpos.mx

    2010-07-01

    This study assesses the toxic effects produced by a Gleysol molic soil contaminated with crude oil on seedlings of two species of legumes. A phytotoxic impact index (IIF) was generated, which includes five parameters measured by relative rates of impact (IRIF{sub (x)}) for variables; emergency, height, root length, aboveground biomass and root biomass. Bioassays were conducted under a completely randomized design with three replications under semi-controlled conditions, to assess the sensitivity of Leucaena leucocephala and Crotalaria incana at different concentrations of TPH (total petroleum hydrocarbons). Effects were highly significant (P {<=} 0.01) with increasing concentrations of HTP in substrate. The emergence of L. leucocephala was 29 % lower with 80 000 mgkg{sup -1} HTP, while C. incana decreased 30 % with 32 000 mgkg{sup -1} TPH respect to control. Both species showed a five-day delay in the emergence of seedlings when exposed to high levels of TPH. A significant decrease in the accumulation of dry matter (DM) at concentrations above 20 000 mgkg{sup -1} TPH was observed in both species. The respective IIF declined of 50 % with 80 000 and 25 000 mgkg{sup -1} TPH, but L. leucocephala had no significant effect with 10 000 mgkg{sup -1} TPH. Finally, the EC50 in L. leucocephala, is presented with 80 000 mgkg{sup -1} TPH whereas in C. incana this parameter is noted from 25 000 mgkg{sup -1} TPH. [Spanish] En este estudio se evaluaron los efectos toxicos que produce un suelo Gleysol molico contaminado con petroleo crudo, sobre plantulas de dos especies de leguminosas. Para ello se genero un indice de impacto fitotoxico (IIF) que integra cinco parametros, medidos a traves de indices relativos de impacto (IRIF{sub (x)}) para las variables emergencia, altura, longitud radicular, biomasa aerea y biomasa radicular. Los bioensayos se realizaron bajo un diseno completamente al azar, con tres repeticiones, en condiciones semicontroladas, para evaluar la sensibilidad de

  19. Overexpression of flavodoxin in bacteroids induces changes in antioxidant metabolism leading to delayed senescence and starch accumulation in alfalfa root nodules.

    Science.gov (United States)

    Redondo, Francisco J; de la Peña, Teodoro Coba; Morcillo, César N; Lucas, M Mercedes; Pueyo, José J

    2009-02-01

    Sinorhizobium meliloti cells were engineered to overexpress Anabaena variabilis flavodoxin, a protein that is involved in the response to oxidative stress. Nodule natural senescence was characterized in alfalfa (Medicago sativa) plants nodulated by the flavodoxin-overexpressing rhizobia or the corresponding control bacteria. The decline of nitrogenase activity and the nodule structural and ultrastructural alterations that are associated with nodule senescence were significantly delayed in flavodoxin-expressing nodules. Substantial changes in nodule antioxidant metabolism, involving antioxidant enzymes and ascorbate-glutathione cycle enzymes and metabolites, were detected in flavodoxin-containing nodules. Lipid peroxidation was also significantly lower in flavodoxin-expressing nodules than in control nodules. The observed amelioration of the oxidative balance suggests that the delay in nodule senescence was most likely due to a role of the protein in reactive oxygen species detoxification. Flavodoxin overexpression also led to high starch accumulation in nodules, without reduction of the nitrogen-fixing activity.

  20. Auxin transport, metabolism, and signalling during nodule initiation: indeterminate and determinate nodules

    NARCIS (Netherlands)

    Kohlen, W.; Ng, Jason Liang Pin; Deinum, E.E.; Mathesius, Ulrike

    2018-01-01

    Most legumes can form a unique type of lateral organ on their roots: root nodules. These structures host symbiotic nitrogen-fixing bacteria called rhizobia. Several different types of nodules can be found in nature, but the two best-studied types are called indeterminate and determinate nodules.

  1. NrcR, a New Transcriptional Regulator of Rhizobium tropici CIAT 899 Involved in the Legume Root-Nodule Symbiosis

    Science.gov (United States)

    del Cerro, Pablo; Rolla-Santos, Amanda A. P.; Valderrama-Fernández, Rocío; Gil-Serrano, Antonio; Bellogín, Ramón A.; Gomes, Douglas Fabiano; Pérez-Montaño, Francisco; Megías, Manuel; Hungría, Mariangela; Ollero, Francisco Javier

    2016-01-01

    The establishment of nitrogen-fixing rhizobium-legume symbioses requires a highly complex cascade of events. In this molecular dialogue the bacterial NodD transcriptional regulators in conjunction with plant inducers, mostly flavonoids, are responsible for the biosynthesis and secretion of Nod factors which are key molecules for successful nodulation. Other transcriptional regulators related to the symbiotic process have been identified in rhizobial genomes, including negative regulators such as NolR. Rhizobium tropici CIAT 899 is an important symbiont of common bean (Phaseolus vulgaris L.), and its genome encompasses intriguing features such as five copies of nodD genes, as well as other possible transcriptional regulators including the NolR protein. Here we describe and characterize a new regulatory gene located in the non-symbiotic plasmid pRtrCIAT899c, that shows homology (46% identity) with the nolR gene located in the chromosome of CIAT 899. The mutation of this gene, named nrcR (nolR-like plasmid c Regulator), enhanced motility and exopolysaccharide production in comparison to the wild-type strain. Interestingly, the number and decoration of Nod Factors produced by this mutant were higher than those detected in the wild-type strain, especially under salinity stress. The nrcR mutant showed delayed nodulation and reduced competitiveness with P. vulgaris, and reduction in nodule number and shoot dry weight in both P. vulgaris and Leucaena leucocephala. Moreover, the mutant exhibited reduced capacity to induce the nodC gene in comparison to the wild-type CIAT 899. The finding of a new nod-gene regulator located in a non-symbiotic plasmid may reveal the existence of even more complex mechanisms of regulation of nodulation genes in R. tropici CIAT 899 that may be applicable to other rhizobial species. PMID:27096734

  2. Thyroid Nodules

    Science.gov (United States)

    Thyroid nodules Overview Thyroid nodules are solid or fluid-filled lumps that form within your thyroid, a small gland located at the base of ... just above your breastbone. The great majority of thyroid nodules aren't serious and don't cause ...

  3. Profiling of differentially expressed genes in roots of Robinia pseudoacacia during nodule development using suppressive subtractive hybridization.

    Directory of Open Access Journals (Sweden)

    Hongyan Chen

    Full Text Available BACKGROUND: Legume-rhizobium symbiosis is a complex process that is regulated in the host plant cell through gene expression network. Many nodulin genes that are upregulated during different stages of nodulation have been identified in leguminous herbs. However, no nodulin genes in woody legume trees, such as black locust (Robinia pseudoacacia, have yet been reported. METHODOLOGY/PRINCIPAL FINDINGS: To identify the nodulin genes involved in R. pseudoacacia-Mesorhizobium amorphae CCNWGS0123 symbiosis, a suppressive subtractive hybridization approach was applied to reveal profiling of differentially expressed genes and two subtracted cDNA libraries each containing 600 clones were constructed. Then, 114 unigenes were identified from forward SSH library by differential screening and the putative functions of these translational products were classified into 13 categories. With a particular interest in regulatory genes, twenty-one upregulated genes encoding potential regulatory proteins were selected based on the result of reverse transcription-polymerase chain reaction (RT-PCR analysis. They included nine putative transcription genes, eight putative post-translational regulator genes and four membrane protein genes. The expression patterns of these genes were further analyzed by quantitative RT-PCR at different stages of nodule development. CONCLUSIONS: The data presented here offer the first insights into the molecular foundation underlying R. pseudoacacia-M. amorphae symbiosis. A number of regulatory genes screened in the present study revealed a high level of regulatory complexity (transcriptional, post-transcriptional, translational and post-translational that is likely essential to develop symbiosis. In addition, the possible roles of these genes in black locust nodulation are discussed.

  4. Profiling of Differentially Expressed Genes in Roots of Robinia pseudoacacia during Nodule Development Using Suppressive Subtractive Hybridization

    Science.gov (United States)

    Wang, Xinye; Liu, Sisi; Zhang, Feilong; Wei, Gehong

    2013-01-01

    Background Legume-rhizobium symbiosis is a complex process that is regulated in the host plant cell through gene expression network. Many nodulin genes that are upregulated during different stages of nodulation have been identified in leguminous herbs. However, no nodulin genes in woody legume trees, such as black locust (Robinia pseudoacacia), have yet been reported. Methodology/Principal findings To identify the nodulin genes involved in R. pseudoacacia-Mesorhizobium amorphae CCNWGS0123 symbiosis, a suppressive subtractive hybridization approach was applied to reveal profiling of differentially expressed genes and two subtracted cDNA libraries each containing 600 clones were constructed. Then, 114 unigenes were identified from forward SSH library by differential screening and the putative functions of these translational products were classified into 13 categories. With a particular interest in regulatory genes, twenty-one upregulated genes encoding potential regulatory proteins were selected based on the result of reverse transcription-polymerase chain reaction (RT-PCR) analysis. They included nine putative transcription genes, eight putative post-translational regulator genes and four membrane protein genes. The expression patterns of these genes were further analyzed by quantitative RT-PCR at different stages of nodule development. Conclusions The data presented here offer the first insights into the molecular foundation underlying R. pseudoacacia–M. amorphae symbiosis. A number of regulatory genes screened in the present study revealed a high level of regulatory complexity (transcriptional, post-transcriptional, translational and post-translational) that is likely essential to develop symbiosis. In addition, the possible roles of these genes in black locust nodulation are discussed. PMID:23776436

  5. Isolation and characterization of the heavy metal resistant bacteria CCNWRS33-2 isolated from root nodule of Lespedeza cuneata in gold mine tailings in China

    International Nuclear Information System (INIS)

    Wei Gehong; Fan Lianmei; Zhu Wenfei; Fu Yunyun; Yu Jianfu; Tang Ming

    2009-01-01

    A total of 108 strains of bacteria were isolated from root nodules of wild legumes growing in gold mine tailings in northwest of China and were tested for heavy metal resistance. The results showed that the bacterial strain CCNWRS33-2 isolated from Lespedeza cuneata was highly resistant to copper, cadmium, lead and zinc. The strain had a relatively high mean specific growth rate under each heavy metal stress test and exhibited a high degree of bioaccumulation ability. The partial sequence of the copper resistance gene copA was amplified from the strain and a sequence comparison with our Cu-resistant PCR fragment showed a high homology with Cu-resistant genes from other bacteria. Phylogenetic analysis based on the 16S rRNA gene sequence showed that CCNWRS33-2 belongs to the Rhizobium-Agrobacterium branch and it had 98.9% similarity to Agrobactrium tumefaciens LMG196

  6. Isolation and characterization of the heavy metal resistant bacteria CCNWRS33-2 isolated from root nodule of Lespedeza cuneata in gold mine tailings in China

    Energy Technology Data Exchange (ETDEWEB)

    Wei Gehong [College of Life Science, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Northwest A and F University, Yangling Shaanxi 712100 (China)], E-mail: weigehong@yahoo.com.cn; Fan Lianmei; Zhu Wenfei; Fu Yunyun; Yu Jianfu; Tang Ming [College of Life Science, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Northwest A and F University, Yangling Shaanxi 712100 (China)

    2009-02-15

    A total of 108 strains of bacteria were isolated from root nodules of wild legumes growing in gold mine tailings in northwest of China and were tested for heavy metal resistance. The results showed that the bacterial strain CCNWRS33-2 isolated from Lespedeza cuneata was highly resistant to copper, cadmium, lead and zinc. The strain had a relatively high mean specific growth rate under each heavy metal stress test and exhibited a high degree of bioaccumulation ability. The partial sequence of the copper resistance gene copA was amplified from the strain and a sequence comparison with our Cu-resistant PCR fragment showed a high homology with Cu-resistant genes from other bacteria. Phylogenetic analysis based on the 16S rRNA gene sequence showed that CCNWRS33-2 belongs to the Rhizobium-Agrobacterium branch and it had 98.9% similarity to Agrobactrium tumefaciens LMG196.

  7. Growth behaviour and bioproduction of indole acetic acid by a Rhizobium sp. isolated from root nodules of a leguminous tree Dalbergia lanceolaria.

    Science.gov (United States)

    Ghosh, A C; Basu, P S

    2002-07-01

    The Rhizobium sp. isolated from healthy and mature root nodules of a leguminous tree, Dalbergia lanceolaria Linn. f., preferred mannitol and KNO3 for growth as carbon and nitrogen sources, respectively. The bacterium produced a high amount (22.3 microg/ml) of indole acetic acid (IAA) from L-tryptophan supplemented basal medium. Growth and IAA production started simultaneously. IAA production was maximum at 20 hr when the bacteria reached the stationary phase of growth. Cultural requirements were optimized for maximum growth and IAA production. The IAA production by the Rhizobium sp. was increased by 270.8% over control when the medium was supplemented with mannitol (1%,w/v), SDS (1 microg/ml), L-asparagine (0.02%,w/v) and biotin (1 microg/ml) in addition to L-tryptophan (2.5 mg/ml). The possible role of IAA production in the symbiosis is discussed.

  8. Acylated pelargonidin 3-sambubioside-5-glucosides in Matthiola incana.

    Science.gov (United States)

    Saito, N; Tatsuzawa, F; Hongo, A; Win, K W; Yokoi, M; Shigihara, A; Honda, T

    1996-04-01

    Ten acylated pelargonidin 3-sambubioside-5-glucosides were isolated from the red-purple flowers of Matthiola incana, and also pelargonidin 3-glucoside was isolated from the brownish-red flowers of this plant. FAB mass measurements of 10 acylated anthocyanins gave their molecular ions [M]+ at 903-1195 m/z, which were based on acylated pelargonidin 3-sambubioside-5-glucosides with malonic acid, sinapic acid, p-coumaric acid, caffeic acid and/or ferulic acid. This was confirmed by the analysis of NMR spectra and the experiments of acid and alkaline hydrolysis. By spectral and chemical methods, seven of the 10 pigments were determined to be pelargonidin 3-O-[2-O-(2-O-(acyl-I)-beta-D-xylopyranosyl)- 6-O-(acyl-II)-beta-D-glucopyranoside]-5-O-[6-O-(malonyl)-beta-D- glucopyranoside], in which acyl moieties varied between sinapic, ferulic, caffeic and p-coumaric acids. The occurrence of these pigments was examined in 10 red-purple, 10 salmon-pink, three apricot and three copper colour cultivars of M. incana by HPLC. The acylated pelargonidin 3-sambubioside-5-glucosides were present as the dominant pigments in the red-purple, salmon-pink and apricot colour cultivars. On the other hand, pelargonidin 3-glucoside was present as a dominant anthocyanin in the copper colour cultivars and also pelargonidin 3-sambubioside-5-glucoside was confirmed by HPLC as a minor pigment in the copper colour flowers.

  9. W342F Mutation in CCaMK Enhances Its Affinity to Calmodulin But Compromises Its Role in Supporting Root Nodule Symbiosis in Medicago truncatula

    Directory of Open Access Journals (Sweden)

    Edgard Jauregui

    2017-11-01

    Full Text Available The calcium/calmodulin-dependent protein kinase (CCaMK is regulated by free Ca2+ and Ca2+-loaded calmodulin. This dual binding is believed to be involved in its regulation and associated physiological functions, although direct experimental evidence for this is lacking. Here we document that site-directed mutations in the calmodulin-binding domain of CCaMK alters its binding capacity to calmodulin, providing an effective approach to study how calmodulin regulates CCaMK in terms of kinase activity and regulation of rhizobial symbiosis in Medicago truncatula. We observed that mutating the tryptophan at position 342 to phenylalanine (W342F markedly increased the calmodulin-binding capability of the mutant. The mutant CCaMK underwent autophosphorylation and catalyzed substrate phosphorylation in the absence of calcium and calmodulin. When the mutant W342F was expressed in ccamk-1 roots, the transgenic roots exhibited an altered nodulation phenotype. These results indicate that altering the calmodulin-binding domain of CCaMK could generate a constitutively activated kinase with a negative role in the physiological function of CCaMK.

  10. Blue light does not inhibit nodulation in Sesbania rostrata.

    Science.gov (United States)

    Shimomura, Aya; Arima, Susumu; Hayashi, Makoto; Maymon, Maskit; Hirsch, Ann M; Suzuki, Akihiro

    2017-01-02

    Earlier, we reported that root nodulation was inhibited by blue light irradiation of Lotus japonicus. Because some legumes do not establish nodules exclusively on underground roots, we investigated whether nodule formation in Sesbania rostrata, which forms both root and "stem" nodules following inoculation with Azorhizobium caulinodans, is inhibited by blue light as are L. japonicus nodules. We found that neither S. rostrata nodulation nor nitrogen fixation was inhibited by blue light exposure. Moreover, although A. caulinodans proliferation was not affected by blue light irradiation, bacterial survival was decreased. Therefore, blue light appears to impose different responses depending on the legume-rhizobial symbiosis.

  11. The Influence of the Host Plant Is the Major Ecological Determinant of the Presence of Nitrogen-Fixing Root Nodule Symbiont Cluster II Frankia Species in Soil.

    Science.gov (United States)

    Battenberg, Kai; Wren, Jannah A; Hillman, Janell; Edwards, Joseph; Huang, Liujing; Berry, Alison M

    2017-01-01

    The actinobacterial genus Frankia establishes nitrogen-fixing root nodule symbioses with specific hosts within the nitrogen-fixing plant clade. Of four genetically distinct subgroups of Frankia, cluster I, II, and III strains are capable of forming effective nitrogen-fixing symbiotic associations, while cluster IV strains generally do not. Cluster II Frankia strains have rarely been detected in soil devoid of host plants, unlike cluster I or III strains, suggesting a stronger association with their host. To investigate the degree of host influence, we characterized the cluster II Frankia strain distribution in rhizosphere soil in three locations in northern California. The presence/absence of cluster II Frankia strains at a given site correlated significantly with the presence/absence of host plants on the site, as determined by glutamine synthetase (glnA) gene sequence analysis, and by microbiome analysis (16S rRNA gene) of a subset of host/nonhost rhizosphere soils. However, the distribution of cluster II Frankia strains was not significantly affected by other potential determinants such as host-plant species, geographical location, climate, soil pH, or soil type. Rhizosphere soil microbiome analysis showed that cluster II Frankia strains occupied only a minute fraction of the microbiome even in the host-plant-present site and further revealed no statistically significant difference in the α-diversity or in the microbiome composition between the host-plant-present or -absent sites. Taken together, these data suggest that host plants provide a factor that is specific for cluster II Frankia strains, not a general growth-promoting factor. Further, the factor accumulates or is transported at the site level, i.e., beyond the host rhizosphere. Biological nitrogen fixation is a bacterial process that accounts for a major fraction of net new nitrogen input in terrestrial ecosystems. Transfer of fixed nitrogen to plant biomass is especially efficient via root nodule

  12. Manganese nodules

    Science.gov (United States)

    Hein, James R.; Harff, Jan; Petersen, Sven; Thiede, Jorn

    2016-01-01

    The existence of manganese (Mn) nodules (Figure 1) has been known since the late 1800s when they were collected during the Challenger expedition of 1873–1876. However, it was not until after WWII that nodules were further studied in detail for their ability to adsorb metals from seawater. Many of the early studies did not distinguish Mn nodules from Mn crusts. Economic interest in Mn nodules began in the late 1950s and early 1960s when John Mero finished his Ph.D. thesis on this subject, which was published in the journal Economic Geology (Mero, 1962) and later as a book (Mero, 1965). By the mid-1970s, large consortia had formed to search for and mine Mn nodules that occur between the Clarion and Clipperton fracture zones (CCZ) in the NE Pacific (Figure 2). This is still the area considered of greatest economic potential in the global ocean because of high nickel (Ni), copper (Cu), and Mn contents and the dense distribution of nodules in the area. While the mining of nodules was fully expected to begin in the late 1970s or early 1980s, this never occurred due to a downturn in the price of metals on the global market. Since then, many research cruises have been undertaken to study the CCZ nodules, and now 15 contracts for exploration sites have been given or are pending by the International Seabed Authority (ISA). Many books and science journal articles have been published summarizing the early work (e.g., Baturin, 1988; Halbach et al., 1988), and research has continued to the present day (e.g., ISA, 1999; ISA, 2010). Although the initial attraction for nodules was their high Ni, Cu, and Mn contents, subsequent work has shown that nodules host large quantities of other critical metals needed for high-tech, green-tech, and energy applications (Hein et al., 2013; Hein and Koschinsky, 2014).

  13. Studies on the fate of homologous DNA applied to seedlings of Matthiola incana.

    Science.gov (United States)

    Hemleben, V; Ermisch, N; Kimmich, D; Leber, B; Peter, G

    1975-08-15

    Seedlings of Matthiola incana (crucifer) are able to take up exogenous homologous DNA by the roots. DNA homogenously labelled with [3H]adenine and 5-bromodeoxyuridine is incorporated into the plants in a macromolecular form. Intact donor DNA and a fraction with a buoyant density intermediate between that of the donor and the recipient DNA can be recovered. Analysis of this intermediate fraction by ultrasonication and alkali treatment allows the suggestion that homologous DNA is integrated as a double-stranded DNA which becomes covalently linked to the recipient DNA. Control experiments in which seedlings were incubated in a mixture simulating donor DNA degradation products in the presence and absence of unlabelled competitors suggest that these results are not due to the breakdown of donor DNA and reincorporation of the products during DNA synthesis in the recipient plants. When ultrasonicated or thermally denatured DNA is applied to the plants it may be degraded and reused for recipient DNA synthesis but it is not recovered in a macromolecular form. The possibility that the intermediate DNA fraction arises by bacterial contamination of the plants can be excluded by several arguments. Autoradiographic studies show that at least part of the radioactivity of the donor DNA taken up by the plants is associated with the cell nucleus.

  14. Acylated cyanidin 3-sambubioside-5-glucosides in Matthiola incana.

    Science.gov (United States)

    Saito, N; Tatsuzawa, F; Nishiyama, A; Yokoi, M; Shigihara, A; Honda, T

    1995-03-01

    Four acylated cyanidin 3-sambubioside-5-glucosides were isolated from purple-violet flowers of Matthiola incana and their structures were determined by chemical and spectroscopic methods. Three acylated anthocyanins were cyanidin 3-O-(6-O-acyl-2-O-(2-O-sinapyl-beta-D-xylopyranosyl)-beta-D- glucopyranosides)-5-O-(6-O-malonyl-beta-D-glucopyranosides), in which the acyl group is p-coumaryl, caffeyl or ferulyl, respectively. The remaining pigment is free from malonic acid and was identified as cyanidin 3-O-(6-O-trans-ferulyl-2-O-(2- O-trans-sinapyl-beta-D-xylopyranosyl)-beta-D-glucopyranoside)-5-O- (beta-D-glucopyranoside). Analysis of the anthocyanin constituents in 16 purple-violet cultivars revealed that they contained the above triacylated anthocyanins in variable amounts as main pigments. An aromatic pair of pigments containing sinapic and ferulic acids are considered to produce an important intramolecular effect, making bluish colours in these flowers.

  15. MtNF-YA1, a central transcriptional regulator of symbiotic nodule development, is also a determinant of Medicago truncatula susceptibility towards a root pathogen.

    Directory of Open Access Journals (Sweden)

    Thomas Rey

    2016-12-01

    Full Text Available Plant NF-Y transcription factors control a wide array of biological functions enabling appropriate reproductive and developmental processes as well as adaptation to various abiotic and biotic environments. In Medicago truncatula, MtNF-YA1 was previously identified as a key determinant for nodule development and establishment of rhizobial symbiosis. Here we highlight a new role for this protein in compatibility to Aphanomyces euteiches, a root pathogenic oomycete. The Mtnf-ya1-1 mutant plants showed better survival rate, reduced symptoms, and increased development of their root apparatus as compared to their wild type background A17. MtNF-YA-1 was specifically up-regulated by A. euteiches in F83005.5, a highly susceptible natural accession of M. truncatula while transcript level remained stable in A17, which is partially resistant. The role of MtNF-YA1 in F83005.5 susceptibility was further documented by reducing MtNF-YA1 expression either by overexpression of the miR169q, a microRNA targeting MtNF-YA1, or by RNAi approaches leading to a strong enhancement in the resistance of this susceptible line. Comparative analysis of the transcriptome of wild type and Mtnf-ya1-1 led to the identification of 1509 differentially expressed genes. Among those, almost 36 defence-related genes were constitutively expressed in Mtnf-ya1-1, while 20 genes linked to hormonal pathways were repressed. In summary, we revealed an unexpected dual role for this symbiotic transcription factor as a key player in the compatibility mechanisms to a pathogen.

  16. Thyroid nodule

    Science.gov (United States)

    ... symptoms, including: Fatigue Palpitations Chest pain Memory loss Thyroid nodules are sometimes found in people who have Hashimoto's disease. This may cause symptoms of an underactive thyroid gland, such as: Dry ...

  17. Final Report Grant No. DE-FG02-98ER20307 Lipopolysaccharide Structures and Genes Required for Root Nodule Development August 1, 2004 to July 31, 2008

    Energy Technology Data Exchange (ETDEWEB)

    Noel, K. Dale [Marquette Univ., Milwaukee,WI (United States)

    2008-12-07

    This project dealt with the plant-bacterial symbiosis that gives rise to root nodules on leguminous plants in which the bacteria carry out nitrogen fixation. Nitrogen fixation, like carbon dioxide fixation, is essential for life on planet earth, and this symbiosis is estimated to account for half of all nitrogen fixed on land. Aside from being important for the sustenance of global life, this ability allows legumes to grow without nitrogen fertilizers. Basic studies such as this project are aimed at understanding the symbiosis well enough that eventually it can be engineered into important crop species so that they no longer depend on nitrogen fertilizer for growth. The production and distribution of excessive fertilizer needed for optimal crop yields is responsible for a significant portion of the energy costs in agriculture. The specific aims of this work were to further the understanding of a bacterial factor that is essential for the symbiotic infection process. This factor is a bacterial surface molecule, lipopolysaccharide O antigen. In this project we showed that, not only the presence, but the specific structure of this molecule is crucial for infection. Although the success of bacterial infections in many pathogenic and mutualistic interactions have been shown to depend on intact O antigen, it has been very rare to establish that specific features of the structure are important. One of the features in this case is the presence of one additional methyl group on one sugar in the O antigen. It is very surprising that such a minor change should have an observable effect. This work sets the stage for biochemical studies of possible plant receptors that may be involved. During the course of this grant period, we developed a method of testing the importance of this bacterial component at stages of nodule development beyond the step that is blocked by null mutation. The method works adequately for this purpose and is being improved. It has implications for testing

  18. Solitary pulmonary nodule

    Science.gov (United States)

    Lung cancer - solitary nodule; Infectious granuloma - pulmonary nodule; SPN ... More than half of all solitary pulmonary nodules are noncancerous ... infections. Infectious granulomas (which are formed by cells as ...

  19. Nitrogen fixation in lysimeter-grown grey alder (Alnus incana (L.) Moench.) saplings - influence of nitrogen fertilization

    Energy Technology Data Exchange (ETDEWEB)

    Ericsson, Tom; Rytter, L.

    1998-07-01

    A lysimeter study was started in order to test if nitrogen fixation as well as biomass production in grey alder plantations (Alnus incana (L.) Moench.) can be stimulated by daily addition of small N doses. One-year-old grey alder saplings were planted in undrained lysimeters, each filled with 200 litres of quartz sand. Water and a low-concentrated balanced nutrient solution were distributed daily via a drip irrigation system. In this paper a complete N budget for the first growing season is presented. The results showed that presence of mineral N in the growth substrate had no beneficial effect on growth during the first growing season. The capacity of the plants to make use of the daily N additions was overestimated in this investigation. Almost twice as much N was added with fertilizers as the amount of N accumulating in the tissues. Consequently, the N concentration in the drainage water increased and the annual rate of N{sub 2}-fixation was strongly suppressed, 31 mg N plant{sup -1} (1 kg N ha{sup -1}) versus 1700 mg N plant{sup -1} (32 kg N ha{sup -1}) in the controls. However, no harmful effect of the elevated soil-N concentration on nodule development could be detected.

  20. Notes on the distribution of Helichrysum Melitense, Hyoseris Frutescens and MatthiolaIncana Melitensis in the Maltese Islands

    OpenAIRE

    Sciberras, Arnold; Sciberras, Jeffrey

    2009-01-01

    Considerations are made on the historical distribution of Helichrysum melitense, Hyoseris frutescens and Matthiola incana subsp. melitensis, three floral species endemic to the Maltese Islands, whilst new records for the three species are also reported. A new variety of Matthiola incana subsp. melitensis is also recorded, whilst biogeographical aspects are also discussed for the three species.

  1. Evaluation of antioxidant, free radical scavenging and antimicrobial, activity of Quercus incana Roxb.

    Directory of Open Access Journals (Sweden)

    Rizwana eSarwar

    2015-11-01

    Full Text Available Considering the indigenous utilization of Quercus incana Roxb., the present study deals with the investigation of antioxidant, free radical scavenging activity, total phenolic content and antimicrobial activity of Quercus incana Roxb. In vitro antioxidant activity of the plant fractions were determined by DPPH and NO scavenging method. Total phenolic contents were determined by gallic acid equivalent (GAE and antimicrobial activities were determined by agar well diffusion method. It was observed that Quercus incana Roxb. showed significant antibacterial activity against Gram-positive and Gram-negative bacteria. n-Butanol fraction showed maximum activity against Micrococcus leuteus with 19 mm zone of inhibition. n-Butanol fraction of Quercus incana Roxb. showed immense antifungal activity against Aspergillus niger (32 mm ± 0.55 and Aspergillus flavus (28 mm ± 0.45. Similarly n-butanol fraction showed relatively good antioxidant activity with IC50 value of 55.4 ± 0.21μg/mL. The NO scavenging activity of ethyl acetate fraction (IC50 = 23.21 ± 0.31 μg/mL was fairly good compared to other fractions. The current study of Quercus incana Roxb. suggests the presences of synergetic action of some biological active compounds that may be present in the leaves of medicinal plant. Further studies are needed to better characterize the important active constituents responsible for the antimicrobial, antioxidant and free radical scavenging activity.

  2. Molecular characterization of a double-flower mutation in Matthiola incana.

    Science.gov (United States)

    Nakatsuka, Takashi; Koishi, Kanae

    2018-03-01

    The double flower is one of the most important traits in the floricultural plant Matthiola incana. Although a "doubleness" locus (S/s) was defined by genetic analysis a century ago, the gene responsible for double flowers has not been identified in M. incana. We isolated MiAG from M. incana cultivars, and its sequence and genomic structure were found to be highly similar to the AGAMOUS gene in Arabidopsis. Two independent mutated alleles miag1 and miag2 were identified from the double-flowered individuals of M. incana cultivars. Deletions of 135 bp (from the 2nd exon to the 2nd intron) and 89 bp (from the 7th intron to the 8th exon) were detected in miag1 and miag2, respectively. No transcript was detected in flower buds from miag1 alleles in corresponding cultivars, whereas three mRNA variants with frameshifts were transcribed from the miag2 allele in other cultivars. Thus, two mutated alleles corresponding to the s locus contributed to the 'eversporting' type double-flower cultivars in M. incana. Moreover, we also developed co-dominant molecular markers to describe the genotypes of the three alleles of MiAG. Using these DNA markers allows for selection of single- or double-flowered individuals among seedlings that do not display phenotypic differences. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. An overview of the metabolic differences between Bradyrhizobium japonicum 110 bacteria and differentiated bacteroids from soybean (Glycine max) root nodules: an in vitro 13C- and 31P-nuclear magnetic resonance spectroscopy study

    International Nuclear Information System (INIS)

    Vauclare, Pierre; Bligny, Richard; Gout, Elisabeth; Widmer, Francois

    2013-01-01

    Bradyrhizobium japonicum is a symbiotic nitrogen-fixing soil bacteria that induce root nodules formation in legume soybean (Glycine max.). Using 13 C- and 31 P-nuclear magnetic resonance (NMR) spectroscopy, we have analysed the metabolite profiles of cultivated B. japonicum cells and bacteroids isolated from soybean nodules. Our results revealed some quantitative and qualitative differences between the metabolite profiles of bacteroids and their vegetative state. This includes in bacteroids a huge accumulation of soluble carbohydrates such as trehalose, glutamate, myo-inositol and homo-spermidine as well as Pi, nucleotide pools and intermediates of the primary carbon metabolism. Using this novel approach, these data show that most of the compounds detected in bacteroids reflect the metabolic adaptation of rhizobia to the surrounding microenvironment with its host plant cells. (authors)

  4. Quantitative evaluation of acidity tolerance of root nodule bacteria Avaliação quantitativa da tolerância de rizóbios à acidez

    Directory of Open Access Journals (Sweden)

    Luiz Antonio de Oliveira

    1999-07-01

    Full Text Available Quantification of acidity tolerance in the laboratory may be the first step in rhizobial strain selection for the Amazon region. The present method evaluated rhizobia in Petri dishes with YMA medium at pH 6.5 (control and 4.5, using scores of 1.0 (sensitive, "no visible" growth to 4.0 (tolerant, maximum growth. Growth evaluations were done at 6, 9, 12, 15 and 18 day periods. This method permits preliminary selection of root nodule bacteria from Amazonian soils with statistical precision. Among the 31 rhizobia strains initially tested, the INPA strains 048, 078, and 671 presented scores of 4.0 at both pHs after 9 days of growth. Strain analyses using a less rigorous criterion (growth scores higher than 3.0 included in this highly tolerant group the INPA strains 511, 565, 576, 632, 649, and 658, which grew on the most diluted zone (zone 4 after 9 days. Tolerant strains still must be tested for nitrogen fixation effectiveness, competitiveness for nodule sites, and soil persistence before their recommendation as inoculants.A quantificação da tolerância à acidez em testes de laboratório pode ser o primeiro passo na seleção de estirpes de rizóbios para a Amazônia. O presente método avaliou isolamentos de rizóbios em placas de Petri contendo meio YMA com pHs 6,5 (controle e 4,5, usando notas de 1,0 (sensíveis, sem crescimento visual, até 4,0 (tolerantes, máximo crescimento. As avaliações foram realizadas aos 6, 9, 12, 15 e 18 dias de crescimento. O método permite selecionar preliminarmente, rizóbios isolados de solos da Amazônia, com precisão estatística. Entre as 31 estirpes inicialmente testadas, as estirpes INPA 048, 078 e 671 apresentaram notas iguais a 4,0 em ambos os pHs testados após os 9 dias de crescimento. Ao se analisar as estirpes usando um sistema menos rigoroso (nota de crescimento acima de 3,0, foi possível incluir também neste grupo, as estirpes INPA 511, 565, 576, 632, 649 e 658, que cresceram na zona mais dilu

  5. Effectiveness of native Rhizobium on nodulation and growth ...

    African Journals Online (AJOL)

    This study was conducted in order to evaluate the symbiotic effectiveness of native Rhizobium isolated strains on number of nodule, weight, and morphological properties of dry bean. To realize this purpose, fresh and healthy root nodules were collected from major dry bean-growing districts of Konya, Turkey. These nodules ...

  6. 2,4-Dichlorophenoxyacetic acid (2,4-D)- and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)-degrading gene cluster in the soybean root-nodulating bacterium Bradyrhizobium elkanii USDA94.

    Science.gov (United States)

    Hayashi, Shohei; Sano, Tomoki; Suyama, Kousuke; Itoh, Kazuhito

    2016-01-01

    Herbicides 2,4-dichlorophenoxyacetic acid (2,4-D)- and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)-degrading Bradyrhizobium strains possess tfdAα and/or cadABC as degrading genes. It has been reported that root-nodulating bacteria belonging to Bradyrhizobium elkanii also have tfdAα and cadA like genes but lack the ability to degrade these herbicides and that the cadA genes in 2,4-D-degrading and non-degrading Bradyrhizobium are phylogenetically different. In this study, we identified cadRABCK in the genome of a type strain of soybean root-nodulating B. elkanii USDA94 and demonstrated that the strain could degrade the herbicides when cadABCK was forcibly expressed. cadABCK-cloned Escherichia coli also showed the degrading ability. Because co-spiked phenoxyacetic acid (PAA) could induce the degradation of 2,4-D in B. elkanii USDA94, the lack of degrading ability in this strain was supposed to be due to the low inducing potential of the herbicides for the degrading gene cluster. On the other hand, tfdAα from B. elkanii USDA94 showed little potential to degrade the herbicides, but it did for 4-chlorophenoxyacetic acid and PAA. The 2,4-D-degrading ability of the cad cluster and the inducing ability of PAA were confirmed by preparing cadA deletion mutant. This is the first study to demonstrate that the cad cluster in the typical root-nodulating bacterium indeed have the potential to degrade the herbicides, suggesting that degrading genes for anthropogenic compounds could be found in ordinary non-degrading bacteria. Copyright © 2016 Elsevier GmbH. All rights reserved.

  7. Construction of 12 EST libraries and characterization of a 12,226 EST dataset for chicory (Cichorium intybus root, leaves and nodules in the context of carbohydrate metabolism investigation

    Directory of Open Access Journals (Sweden)

    Boutry Marc

    2009-01-01

    Full Text Available Abstract Background The industrial chicory, Cichorium intybus, is a member of the Asteraceae family that accumulates fructan of the inulin type in its root. Inulin is a low calories sweetener, a texture agent and a health promoting ingredient due to its prebiotic properties. Average inulin chain length is a critical parameter that is genotype and temperature dependent. In the context of the study of carbohydrate metabolism and to get insight into the transcriptome of chicory root and to visualize temporal changes of gene expression during the growing season, we obtained and characterized 10 cDNA libraries from chicory roots regularly sampled in field during a growing season. A leaf and a nodule libraries were also obtained for comparison. Results Approximately 1,000 Expressed Sequence Tags (EST were obtained from each of twelve cDNA libraries resulting in a 12,226 EST dataset. Clustering of these ESTs returned 1,922 contigs and 4,869 singlets for a total of 6,791 putative unigenes. All ESTs were compared to public sequence databases and functionally classified. Data were specifically searched for sequences related to carbohydrate metabolism. Season wide evolution of functional classes was evaluated by comparing libraries at the level of functional categories and unigenes distribution. Conclusion This chicory EST dataset provides a season wide outlook of the genes expressed in the root and to a minor extent in leaves and nodules. The dataset contains more than 200 sequences related to carbohydrate metabolism and 3,500 new ESTs when compared to other recently released chicory EST datasets, probably because of the season wide coverage of the root samples. We believe that these sequences will contribute to accelerate research and breeding of the industrial chicory as well as of closely related species.

  8. Cholesterol and triglyceride reduction in rats fed Matthiola incana seed oil rich in (n-3) fatty acids.

    Science.gov (United States)

    Yaniv, Z; Schafferman, D; Shamir, I; Madar, Z

    1999-02-01

    Seeds of Matthiola incana contain oil rich (55-65%) in (n-3) linolenic acid. Selected lines were developed and evaluated for their agronomic and chemical parameters. Extracted oil was fed for 6 weeks to rats, which were compared with rats fed a diet containing coconut oil or sunflower oil. Cholesterol levels were significantly lowest in rats fed diets rich in M. incana oil (27% reduction), and triglycerides were significantly lower in rats receiving either M. incana or sunflower oil (36% reduction). The contents of arachidonic acid and other (n-6) fatty acids were significantly the lowest in the liver and plasma of rats that had received M. incana oil. The levels of (n-3) fatty acids were significantly greater in both the liver and plasma of rats fed M. incana oil. The ratio of (n-3)/(n-6) long-chain fatty acids in the plasma was 7 times higher in rats fed with M. incana oil than in those fed with sunflower oil and 6 times higher than in those fed coconut oil. The results demonstrate for the first time a beneficial effect of dietary M. incana oil in reducing cholesterol levels and increasing (n-3) fatty acid levels in the plasma. This new, terrestrial plant source of (n-3) fatty acids could replace marine oils and thereby contribute beneficially to the human diet.

  9. Allelopathic Effect of Leaf Water Extract of Hoary alyssum (Berteroa incana L. at Rosette Stage on Seed Germination

    Directory of Open Access Journals (Sweden)

    H. Madani

    2012-07-01

    Full Text Available The allelopathic effects of leaves at rosette stage of the hoary alyssum (Berteroa incana L. against some associated grasses like, prairie June grass (Koeleria macrantha, Idaho fescue (Festuca idahoensis, blue-bunch wheatgrass (Pseudoroegneria spicata and cheat grass (Bromus tectorum and its own were investigated. The experiment al materials used were the leaf extracts and its allelopathic effects on seed germination and seedling emergence of the abave mentioned grasses in Petri dishes. According to our study, leaves of hoary alyssum rosettes at stage have the potential to reduce germination rate, root and shoot growth of pasture grasses and hoary alyssum itself due to its allelopathic effect. The leaf leachate solution bioassays also showed that the germination of cheat grass was more susceptible to 4% solution of allelopathic extract of leaves. Hoary alyssum leaf extract also exhibited allelopathic self-inhibition, in both seedling root and shoot growth at 2 and 4% concentrations. Self- inhibitory allelopathic effects of hoary alyssum could also be important in preventing seed germination and seedling establishment of neighboring plant.

  10. VsENOD5, VsENOD12 and VsENOD40 expression during Rhizobium-induced nodule formation on Vicia sativa roots

    DEFF Research Database (Denmark)

    Vijn, I; Yang, W C; Pallisgård, N

    1995-01-01

    We isolated ENOD5, ENOD12 and ENOD40 homologues from Vicia sativa and studied their expression pattern during Rhizobium-induced nodule formation. Comparison of the VsENOD40 nucleotide sequence with the pea, soybean and alfalfa ENOD40 sequences showed that the sequences contain two conserved regions...

  11. Analysis of nodule meristem persistence and ENOD40 functioning in Medicago truncatula nodule formation

    NARCIS (Netherlands)

    Wan Xi,

    2007-01-01

    Medicago root nodules are formed as a result of the interaction of the plant with the soil-borne bacterium Sinorhizobium meliloti. Several plant genes are induced during nodule formation and MtENOD40 is one of the earliest genes activated. The precise function as well as the molecule

  12. Analysis of nodule meristem persistence and ENOD40 functioning in Medicago truncatula nodule formation

    NARCIS (Netherlands)

    Wan Xi,

    2007-01-01

    Medicago root nodules are formed as a result of the interaction of the plant with the soil-borne bacterium Sinorhizobium meliloti. Several plant genes are induced during nodule formation and MtENOD40 is one of the earliest genes activated. The precise function as well as the molecule harboring the

  13. The roots of nodulins.

    NARCIS (Netherlands)

    Nap, J.P.H.; Bisseling, T.

    1990-01-01

    Nodulin gene expression is an integral and highly specific part of the formation of nitrogenfixing nodules on the roots of leguminous plants. Dependent on the time of expression during root nodule development, nodulin genes can be divided into early and late nodulin genes. A brief overview of the

  14. Isolation and sequence analysis of a chalcone synthase cDNA of Matthiola incana R. Br. (Brassicaceae).

    Science.gov (United States)

    Epping, B; Kittel, M; Ruhnau, B; Hemleben, V

    1990-06-01

    A cDNA clone (pcM12) of the chalcone synthase (CHS) of Matthiola incana R. Br. (Brassicaceae) was isolated from a cDNA library, sequenced and analysed. It comprises the complete coding sequence for the CHS and 5' and 3' untranslated regions. The deduced amino acid sequence shows that the Matthiola incana CHS consists of 394 amino acid residues. Comparison with CHS amino acid sequences of other plants indicates more than 82% homology.

  15. The DMI1 and DMI2 Early Symbiotic Genes of Medicago truncatula Are Required for a High-Affinity Nodulation Factor-Binding Site Associated to a Particulate Fraction of Roots1

    Science.gov (United States)

    Hogg, Bridget V.; Cullimore, Julie V.; Ranjeva, Raoul; Bono, Jean-Jacques

    2006-01-01

    The establishment of the legume-rhizobia symbiosis between Medicago spp. and Sinorhizobium meliloti is dependent on the production of sulfated lipo-chitooligosaccharidic nodulation (Nod) factors by the bacterial partner. In this article, using a biochemical approach to characterize putative Nod factor receptors in the plant host, we describe a high-affinity binding site (Kd = 0.45 nm) for the major Nod factor produced by S. meliloti. This site is termed Nod factor-binding site 3 (NFBS3). NFBS3 is associated to a high-density fraction prepared from roots of Medicago truncatula and shows binding specificity for lipo-chitooligosaccharidic structures. As for the previously characterized binding sites (NFBS1 and NFBS2), NFBS3 does not recognize the sulfate group on the S. meliloti Nod factor. Studies of Nod factor binding in root extracts of early symbiotic mutants of M. truncatula reveals that the new site is present in Nod factor perception and does not make infections 3 (dmi3) mutants but is absent in dmi1 and dmi2 mutants. Roots and cell cultures of all these mutants still contain sites similar to NFBS1 and NFBS2, respectively. These results suggest that NFBS3 is different from NFBS2 and NFBS1 and is dependent on the common symbiotic genes DMI1 and DMI2 required for establishment of symbioses with both rhizobia and arbuscular mycorrhizal fungi. The potential role of this site in the establishment of root endosymbioses is discussed. PMID:16377749

  16. Ribonucleic acid from the higher plant Matthiola incana. Molecular weight measurements and DNA-RNA hybridisation studies.

    Science.gov (United States)

    Grierson, D; Hemleben, V

    1977-04-04

    The percentage of DNA from the crucifer Matthiola incana coding for different types of RNA was measured by filter saturation hybridisation experiments using RNA labelled in vivo. In addition, the melting curves of the various DNA - RNA hybrids formed and the buoyant densities of the DNA sequences complementary to different types of RNA were measured. 1. The RNA preparations used were 25, 18, and 5 S rRNA and 4 S RNA, purified by gel electrophoresis, and poly(A)-containing RNA purified by oligo-(dT)-cellulose chromatography. The molecular weights of the 25 S and 18 S rRNAs, calculated from the mobility in formamide-acrylamide gels relative to Escherichia coli RNA, are 1.25 - 10(6) and 0.64 - 10(6). The rRNA precursor has a molecular weight of approx. 2.1 - 10(6) and the average molecular weight of the poly(A)-containing RNA from both cotyledons and roots is 4 - 10(5). 2. The percentage of the genome, calculated on the basis of double-stranded DNA, coding for these RNAs and the estimated number of genes per haploid DNA amount are approximately 0.46% and 1100 for 25 S plus 18 S rRNA, 0.032% and 3600 for 5 S rRNA and 0.072% and 13 000 for 4 S RNA. In filter hybridisation experiments very little hybridisation of poly(A)-containing RNA was found. A rapidly-hybridising component is attributed to small amounts of contaminating rRNA. 3. M. incana DNA has a main band at 1.697 g - ml-1 in CsCl and a satellite constituting approximately 3% of the DNA, at 1.708 g - ml-1 - 25 and 18 S rRNA hybridise to DNA with a buoyant density of 1.701--2 g - ml-1. The buoyant density of 5 S DNA is slightly less at 1.700--1 g - ml-1. 4. S RNA hybridises to at least two separate regions, one within the main-band DNA and a second lighter component. None of the RNAs tested hybridised to the satellite DNA. The Tm of the DNA - RNA hybrids in 1 X SSC is 89 degrees C for 25 S rRNA, 85 degrees C for 5 S rRNA and 82 degrees C for 4 S RNA. 4. 5 and 4 S RNA preparations contain fragments which hybridise

  17. Bioactive dihydroxyfuranonaphthoquinones from the bark of Tabebuia incana A.H. Gentry (Bignoniaceae and HPLC analysis of commercial pau d'arco and certified T.incana bark infusions Diidroxifuranonaftoquinonas bioativas das cascas de Tabebuia incana A.H. Gentry (Bignoniaceae e análise por CLAE de infusões de cascas de pau d' arco comercial e T. incana certificada

    Directory of Open Access Journals (Sweden)

    Sabrina Kelly Reis de Morais

    2007-01-01

    Full Text Available Tabebuia incana A.H. Gentry (Bignoniaceae is a tree from the Brazilian Amazon having medicinal uses and is one several Tabebuia spp. known as pau d'arco or palo de arco in this region. Fractionation of the bark ethanolic extract afforded a mixture of 5 and 8-hydroxy-2-(1-hydroxyethylnaphtho[2,3-b]furan-4,9-diones (1 and 2, respectively identified on the basis of nuclear magnetic resonance (NMR, infrared (IR and mass (MS spectra, whose in vitro antimalarial and antitumor activity have been shown previously. This is the first study on T. incana bark, and 2 are described in this species for the first time. Also, high performance liquid chromatography (HPLC analysis of T. incana bark tea revealed the presence of the 1 + 2 mixture peak corresponding to a concentration in the range 10-6-10-5 M. The chromatograms of teas prepared from commercial pau d' arco and T. incana bark were also studied and the presence of the 1 + 2 peak has potential for quality control of commercial plant materials.Tabebuia incana A.H. Gentry (Bignoniaceae é uma árvore da Amazônia brasileira com usos medicinais. É uma de várias espécies de Tabebuia conhecidas como pau d'arco ou palo de arco nesta região. O fracionamento do extrato etanólico das cascas resultou no isolamento da mistura de 5 e 8-hidróxi-2-(1-hidroxietilnafto[2,3-b]furano-4,9-dionas (1 e 2, respectivamente, identificadas com base em seus espectros de ressonância magnética nuclear (RMN, infravermelho (IV e massa (EM, e cujas atividades antimalárica e antitumoral in vitro foram mostradas previamente. Este é o primeiro estudo das cascas de T. incana e a primeira vez que o composto 2 é descrito nesta espécie. Análises por cromatografia liquida de alto empenho (CLAE do chá das cascas de T. incana revelaram a presença de um pico correspondente à mistura de 1 + 2, permitindo inferir uma concentração na faixa de 10-6-10-5 M desses componentes no chá. Os cromatogramas de chás (infusões preparados a

  18. Introduce lichen Lepraria incana as biomonitor of Cesium-137 from Ramsar, northern Iran.

    Science.gov (United States)

    Dalvand, Amin; Jahangiri, Ahmad; Iranmanesh, Jalil

    2016-08-01

    Lichens have been used as biomonitors of airborne radionuclides released in conjunction with nuclear bomb testing as well as nuclear power plant accidents. The potential of lichens for monitoringof radionuclides has been well documented. However, there are no studies that determine natural and artificial radionuclide monitoring by lichens, in Iran. Thus, as a first step, we have conducted a comparison of (137)Csactivity concentration capacity of three epiphytic lichen species including Lepraria incana, Xanthoria parietina and Ramalina farinacea from Ramsar Northern Iran. In this work, accumulation capacity of (137)Cs was determined in 36 lichen samples using a gamma spectrometer equipped with a high purity germanium (HPGe) detector. The results showed that highest accumulation capacity of (137)Cs in the lichen species was found in Lepraria incana and Xanthoria parietina, 30.2, 9.8 Bq/kg respectively, and lowest average accumulation capacity were found in Ramalina farinacea 2.7 Bq/kg (dry weight). This study showed that activity concentration (137)Cs is in crustose > foliose > fruticose lichens in the same biotope. Thus, crustose lichens are capable to accumulate higher (137)Cs than foliose and fruticose species because of different factors such as special morphological characteristics in these species and large surface/volume ratio or longer biological half-life of (137)Cs in lichen Lepraria incana. Therefore, Lepraria incana due to high concentration capability of (137)Cs (approximately 3 and 11 time higher than Xanthoria parietina and Ramalina farinacea, respectively), is introduced as biomonitor of Cesium-137 from Ramsar, North of Iran. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Transcriptomic profiling of Burkholderia phymatum STM815, Cupriavidus taiwanensis LMG19424 and Rhizobium mesoamericanum STM3625 in response to Mimosa pudica root exudates illuminates the molecular basis of their nodulation competitiveness and symbiotic evolutionary history.

    Science.gov (United States)

    Klonowska, Agnieszka; Melkonian, Rémy; Miché, Lucie; Tisseyre, Pierre; Moulin, Lionel

    2018-01-30

    Rhizobial symbionts belong to the classes Alphaproteobacteria and Betaproteobacteria (called "alpha" and "beta"-rhizobia). Most knowledge on the genetic basis of symbiosis is based on model strains belonging to alpha-rhizobia. Mimosa pudica is a legume that offers an excellent opportunity to study the adaptation toward symbiotic nitrogen fixation in beta-rhizobia compared to alpha-rhizobia. In a previous study (Melkonian et al., Environ Microbiol 16:2099-111, 2014) we described the symbiotic competitiveness of M. pudica symbionts belonging to Burkholderia, Cupriavidus and Rhizobium species. In this article we present a comparative analysis of the transcriptomes (by RNAseq) of B. phymatum STM815 (BP), C. taiwanensis LMG19424 (CT) and R. mesoamericanum STM3625 (RM) in conditions mimicking the early steps of symbiosis (i.e. perception of root exudates). BP exhibited the strongest transcriptome shift both quantitatively and qualitatively, which mirrors its high competitiveness in the early steps of symbiosis and its ancient evolutionary history as a symbiont, while CT had a minimal response which correlates with its status as a younger symbiont (probably via acquisition of symbiotic genes from a Burkholderia ancestor) and RM had a typical response of Alphaproteobacterial rhizospheric bacteria. Interestingly, the upregulation of nodulation genes was the only common response among the three strains; the exception was an up-regulated gene encoding a putative fatty acid hydroxylase, which appears to be a novel symbiotic gene specific to Mimosa symbionts. The transcriptional response to root exudates was correlated to each strain nodulation competitiveness, with Burkholderia phymatum appearing as the best specialised symbiont of Mimosa pudica.

  20. Diazotroph-Bacterial Community Structure of Root Nodules Account for Two-Fold Differences in Plant Growth: Consequences for Global Biogeochemical Cycles

    Science.gov (United States)

    Williams, M. A.

    2016-12-01

    The bacterial communities that inhabit and function as mutualists in the nodules of soybean, a major worldwide crop, are a fundamental determinant of plant growth and global nitrogen and carbon cycles. Unfertilized soybean can derive up to 90% of its nitrogen through bacterial-driven diazotrophy. It was the goal of the research in this study to assess whether different bacterial taxa (e.g. Bradyrhizobia spp.) differ in their soybean growth supportive role, which could then feedback to alter global biogeochemical cycling. Using 16S rRNA and NifH genes, nodule bacterial communities were shown to vary across 9 different cultivars of soybean, and that the variation between cultivars were highly correlated to plant yield (97 to 188 bu/Ha) and nitrogen. The relative abundances of gene sequences associated with the closest taxonomic match (NCBI), indicated that several taxa were (r= 0.76) negatively (e.g. Bradyrhizobium sp Ec3.3) or (r= 0.84) positively (e.g. Bradyrhizobium elkanii WSM 2783) correlated with plant yield. Other non-Rhizobiaceae taxa, such as Rhodopseudomonas spp. were also prevalent and correlated with plant yield. Soybeans and other leguminous crops will become increasingly important part of world food production, soil fertility and global biogeochemical cycles with rising population and food demand. The study demonstrates the importance of plant-microbial feedbacks driving plant growth but also ramifications for global cycling of nitrogen and carbon.

  1. Nitrogen fixation and carbon metabolism in legume nodules.

    Science.gov (United States)

    Garg, Neera; Singla, Ranju; Geetanjali

    2004-02-01

    A large amount of energy is utilized by legume nodules for the fixation of nitrogen and assimilation of fixed nitrogen (ammonia) into organic compounds. The source of energy is provided in the form of photosynthates by the host plant. Phosphoenol pyruvate carboxylase (PEPC) enzyme, which is responsible for carbon dioxide fixation in C4 and crassulacean acid metabolism plants, has also been found to play an important role in carbon metabolism in legume root nodule. PEPC-mediated CO2 fixation in nodules results in the synthesis of C4 dicarboxylic acids, viz. aspartate, malate, fumarate etc. which can be transported into bacteroids with the intervention of dicarboxylate transporter (DCT) protein. PEPC has been purified from the root nodules of few legume species. Information on the relationship between nitrogen fixation and carbon metabolism through PEPC in leguminous plants is scanty and incoherent. This review summarizes the various aspects of carbon and nitrogen metabolism in legume root nodules.

  2. Germination, growth and nodulation of Trigonella foenum graecum ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-06-03

    Jun 3, 2009 ... In this work, we analyzed the effects of salinity on seed germination, growth and nodulation of fenugreek plants. The germination of fenugreek seeds was not affected by salt concentrations lower than 140 mM. Two saline tolerant indigenous rhizobia strains were isolated from the root nodules of fenugreek ...

  3. Germination, growth and nodulation of Trigonella foenum graecum ...

    African Journals Online (AJOL)

    In this work, we analyzed the effects of salinity on seed germination, growth and nodulation of fenugreek plants. The germination of fenugreek seeds was not affected by salt concentrations lower than 140 mM. Two saline tolerant indigenous rhizobia strains were isolated from the root nodules of fenugreek grown in two ...

  4. Nodulation potential of four Trifolium repens cultivars under field ...

    African Journals Online (AJOL)

    Four Trifolium repens (white clover) cultivars were evaluated under field conditions to determine the potential of these cultivars to sucessfully develop Rhizobium-associated root nodules. Nodulation of T. repens is often poor, because of suboptimal environmental conditions or absence of host-specific rhizobia. The cultivars ...

  5. ROOT TRAITS AND NODULATION OF RECOMBINANT INBRED BEAN LINES FROM A ‘JAMAPA × CALIMA’ POPULATION INOCULATED WITH TWO STRAINS OF RHIZOBIUM

    Science.gov (United States)

    Bean cultivars of Andean and Middle American origin often have contrasting above-ground traits. Less is known, however, of possible differences in root traits of beans from different gene pools. Recombinant inbred lines (RIL) derived from a cross between the Andean cultivar ‘Calima’ and the Middle A...

  6. Rhizobium nod factors reactivate the cell cycle during infection and nodule primordium formation, but the cycle is only completed in primordium formation.

    NARCIS (Netherlands)

    Yang, W.C.; Blank, de C.; Meskiene, I.; Hirt, H.; Bakker, J.; Kammen, van A.; Franssen, H.; Bisseling, T.

    1994-01-01

    Rhizobia induce the formation of root nodules on the roots of leguminous plants. In temperate legumes, nodule organogenesis starts with the induction of cell divisions in regions of the root inner cortex opposite protoxylem poles, resulting in the formation of nodule primordia. It has been

  7. Role of plant root exudate and Sym plasmid-localized nodulation genes in the synthesis by Rhizobium leguminosarum of Tsr factor, which causes thick and short roots on common vetch

    NARCIS (Netherlands)

    van Brussel, A. A.; Zaat, S. A.; Cremers, H. C.; Wijffelman, C. A.; Pees, E.; Tak, T.; Lugtenberg, B. J.

    1986-01-01

    In a previous paper it was shown that cocultivation of Rhizobium leguminosarum with the plant Vicia sativa subsp. nigra on solid medium causes a changed mode of growth of the plant roots, resulting in thick and short roots (Tsr). The Sym plasmid present in the bacterium appeared to be essential for

  8. Studies on the chalcone synthase gene of two higher plants: petroselinum hortense and matthiola incana

    Energy Technology Data Exchange (ETDEWEB)

    Hemleben, V.; Frey, M.; Rall, S.; Koch, M.; Kittel, M.; Kreuzaler, F.; Ragg, H.; Fautz, E.; Hahlbrock, K.

    1982-01-01

    Two higher plant systems are presented which allow to study coordinated gene expression of the light-induced metabolic pathway of flavonoid biosynthesis: tissue culture cells of Petroselinum hortense (Apiaceae) and different developmental stages of various genotypes of Matthiola incana (Brassicaceae). The gene structure of the chalcone synthase is mainly studied. A cDNA clone (pLF56) of parsley has been constructed and characterized conferring the chalcone synthase gene sequence. Strong cross hybridization between the parsley cDNA and Matthiola DNA allowed to identify a HindIII fragment (6000 bp) identical in size for parsley and different Matthiola wild type lines and a mutant line.

  9. Studies on the chalcone synthase gene of two higher plants: petroselinum hortense and matthiola incana.

    Science.gov (United States)

    Hemleben, V; Frey, M; Rall, S; Koch, M; Kittel, M; Kreuzaler, F; Ragg, H; Fautz, E; Hahlbrock, K

    1982-01-01

    Two higher plant systems are presented which allow to study coordinated gene expression of the light-induced metabolic pathway of flavonoid biosynthesis: tissue culture cells of Petroselinum hortense (Apiaceae) and different developmental stages of various genotypes of Matthiola incana (Brassicaceae). The gene structure of the chalcone synthase is mainly studied. A cDNA clone (pLF56) of parsley has been constructed and characterized conferring the chalcone synthase gene sequence. Strong cross hybridization between the parsley cDNA and Matthiola DNA allowed to identify a HindIII fragment (6000 bp) identical in size for parsley and different Matthiola wild type lines and a mutant line.

  10. Ferric Leghemoglobin in Plant-Attached Leguminous Nodules.

    Science.gov (United States)

    Lee, Kk.; Shearman, L. L.; Erickson, B. K.; Klucas, R. V.

    1995-01-01

    Leghemoglobin (Lb) is essential for nitrogen fixation by intact leguminous nodules. To determine whether ferric Lb (Lb3+) was detectable in nodules under normal or stressed conditions, we monitored the status of Lb in intact nodules attached to sweet clover (Melilotus officinalis) and soybean (Glycine max [L.] Merr.) roots exposed to various conditions. The effects of N2 and O2 streams and elevated nicotinate levels on root-attached nodules were tested to determine whether the spectrophotometric technique was showing the predicted responses of Lb. The soybean and sweet clover nodules' Lb spectra indicated predominantly ferrous Lb and LbO2 in young (34 d) plants. As the nodule aged beyond 45 d, it was possible to induce Lb3+ with a 100% O2 stream (15 min). At 65 d without inducement, the nodule Lb status indicated the presence of some Lb3+ along with ferrous Lb and oxyferrous Lb. Nicotinate and fluoride were used as ligands to identify Lb3+. Computer-calculated difference spectra were used to demonstrate the changes in Lb spectra under different conditions. Some conditions that increased absorbance in the 626 nm region (indicating Lb3+ accumulation) were root-fed ascorbate and dehydroascorbate, plant exposure to darkness, and nodule water immersion. PMID:12228593

  11. Direct detection of radicals in intact soybean nodules

    DEFF Research Database (Denmark)

    Mathieu, C; Moreau, S; Frendo, P

    1998-01-01

    Electron paramagnetic resonance spectroscopy has been employed to examine the nature of the metal ions and radicals present in intact root nodules of soybean plants grown in the absence of nitrate. The spectra obtained from nodules of different ages using this non-invasive technique show dramatic...... differences, suggesting that there are both qualitative and quantitative changes in the metal ion and radical species present. A major component of the spectra obtained from young nodules is assigned to a complex (Lb-NO) of nitric oxide (NO.) with the heme protein leghemoglobin (Lb). This Lb-NO species, which...... has not been previously detected in intact root nodules of plants grown in the absence of nitrate, is thought to be formed by reaction of nitric oxide with iron(II) leghemoglobin. The nitric oxide may be generated from arginine via a nitric oxide synthase-like activity present in the nodules...

  12. Meiotic behaviour and morpho-phenological variation in cut stock (Matthiola incana L. flower

    Directory of Open Access Journals (Sweden)

    Irani Sepideh Famil

    2017-06-01

    Full Text Available Morpho-phenological and meiotic studies were performed in twelve cultivars of Matthiola incana. All of the cultivars were diploid (2n = 2x = 14 with basic chromosome number x = 7. A number of aneuploid PMCs (n + 1 were observed in plants of two cultivars, named ‘Nobel’ (NB and ‘Goddess’ (GD, at the diakinesis stage. Trisomic individuals with the frequency of 20% and 5% and (2n + 1 = 15 somatic chromosomes were observed in seeds obtained from single-flowered plants of the cultivars NB and GD, respectively. An additional chromosome was mostly observed in the form of a chain trivalent or a rod univalent. Various meiotic abnormalities were found in all the cultivars to different degrees. In these cultivars, the percentage of cells with meiotic abnormalities was higher in anaphase I. Cytomixis was observed for the first time in Matthiola incana. ANOVA tests revealed significant differences in morpho-phenological characteristics. ‘Nobel’ differs from the others in all of the vegetative features investigated in this study. All the cultivars studied except ‘Nobel’ and ‘Pacific Crimson’ possessed high pollen fertility (> 90%. Five groups of the cultivars based on morpho-phenological features disagree with the clustering of cultivars based on meiotic traits. It is thought that the various morpho-phenological features observed among the cultivars could be due to their different genetic background and not only to meiotic anomalies.

  13. Improving germination of red elm (Ulmus rubra), gray alder (Alnus incana), and buffaloberry (Shepherdia canadensis) seeds with gibberellic acid

    Science.gov (United States)

    Brenda Morales; Charles Barden; Cheryl Boyer; Jason Griffin; Lillian Fisher; Joni Thompson

    2012-01-01

    Red elm (Ulmus rubra), gray alder (Alnus incana), and buffaloberry (Shepherdia canadensis) are considered important plants for many Native American tribes in the United States. Native Americans use these 3 species for a variety of traditional and medicinal purposes. For example, red elm is still the preferred firewood for the cultural ceremonies of several tribes....

  14. Management of Pulmonary Nodules

    OpenAIRE

    Arvin Aryan

    2010-01-01

    Pulmonary nodule characterization is currently being redefined as new clinical, radiological and pathological data are reported, necessitating a reevaluation of the clinical management."nIn approach to an incidentally detected pulmonary nodule, we should consider that there are different risk situations, different lesion morphologies, and different sizes with various management options."nIn this session we will review the different risk situations for patients with pulmonary nodules...

  15. Micromonospora is a normal occupant of actinorhizal nodules

    Indian Academy of Sciences (India)

    Supplementary table 1. Number of isolates per nodule. Nodule Colonies Average Nodule Colonies Average. AV1 Nodule 1 2 13 EEM Nodule 1 17 9.4. Nodule 2 O Nodule 2 13. Nodule 3 2 Nodule 3 9. AV2 Nodule 1 19 16.1 Nodule 4 7. Nodule 2 25 Nodule 5 18. Nodule 3 38 Nodule 6 4. AV4 Nodule 1 8 14.0 Nodule 7 12.

  16. Medicago LYK3, an entry receptor in rhizobial nodulation factor signaling

    NARCIS (Netherlands)

    Smit, P.; Limpens, E.H.M.; Geurts, R.; Fedorova, E.; Dolgikh, E.; Gough, C.; Bisseling, T.

    2007-01-01

    Rhizobia secrete nodulation (Nod) factors, which set in motion the formation of nitrogen-fixing root nodules on legume host plants. Nod factors induce several cellular responses in root hair cells within minutes, but also are essential for the formation of infection threads by which rhizobia enter

  17. The role of nodules in the tolerance of common bean to iron deficiency.

    Science.gov (United States)

    Slatni, Tarek; Ben Salah, Imen; Kouas, Saber; Abdelly, Chedly

    2014-05-01

    Iron is vital for the establishment and function of symbiotic root nodules of legumes. Although abundant in the environment, Fe is often a limiting nutrient for plant growth due to its low solubility and availability in some soils. We have studied the mechanism of iron uptake in the root nodules of common bean to evaluate the role of nodules in physiological responses to iron deficiency. Based on experiments using full or partial submergence of nodulated roots in the nutrient solution, our results show that the nodules were affected only slightly under iron deficiency, especially when the nodules were submerged in nutrient solution in the tolerant cultivar. In addition, fully submerged root nodules showed enhanced acidification of the nutrient solution and showed higher ferric chelate reductase activity than that of partially submerged roots in plants cultivated under Fe deficiency. The main results obtained in this work suggest that in addition to preferential Fe allocation from the root system to the nodules, this symbiotic organ probably develops some mechanisms to respond to iron deficiency. These mechanisms were implied especially in nodule Fe absorption efficiency and in the ability of this organ to take up Fe directly from the medium.

  18. Rapid Synthesis of Gold Nanoparticles from Quercus incana and Their Antimicrobial Potential against Human Pathogens

    Directory of Open Access Journals (Sweden)

    Rizwana Sarwar

    2017-01-01

    Full Text Available In current study, bioreduction of tetrachloroauric acid (HAuCl4·3H2O was carried out using leaves extract of Quercus incana for nanoparticle synthesis. The nanoparticles were characterized by ultraviolet visible spectrum (UV, Fourier-transform infrared (FT-IR, and transmission electron microscopy (TEM analysis. The gold nanoparticles (GNPs were generally clumpy agglomerates of polydispersed particles, with an average size in the range 5.5–10 nm. The Gas chromatography–mass spectrometry (GC–MS qualitative analysis and FT-IR data supported the presence of bioactive compounds, which are responsible for the metal reduction and nanoparticles stabilization. The biocompatibility of synthesized GNPs was evaluated via antibacterial activity by using human bacterial pathogens. The results showed that synthesized GNPs showed enhanced antibacterial activity against all bacterial pathogens.

  19. Precursors and genetic control of anthocyanin synthesis in Matthiola incana R. Br.

    Science.gov (United States)

    Forkmann, G

    1977-01-01

    After application of dihydroflavonols, naringenin, or suitable substituted chalcones, anthocyanins were synthesized in three genetically defined acyanic lines of Matthiola incana, indicating that the corresponding genetic block concerns the synthesis of the chalcone-flavanone intermediate. Independent of the precursors used, only cyanidin derivatives were produced. This supports the hypothesis that the oxygenation pattern of the B ring in anthocyanin formation is determined at a stage of a C15 intermediate. In addition to the gene responsible for the oxygenation of the 3' position, the genes responsible for the glycosylation in the 3 and 5 positions of the anthocyanin molecule, and those responsible for the acylation with various hydroxycinnamic acids can still exert their influence. Two further genetically defined lines containing flavonol glycosides were not able to synthesize anthocyanins with any of the precursors tested. Their genetic blocks are assumed to be localized after dihydroflavonol synthesis but before anthocyanin formation.

  20. Crowdsourcing the nodulation gene network discovery environment.

    Science.gov (United States)

    Li, Yupeng; Jackson, Scott A

    2016-05-26

    The Legumes (Fabaceae) are an economically and ecologically important group of plant species with the conspicuous capacity for symbiotic nitrogen fixation in root nodules, specialized plant organs containing symbiotic microbes. With the aim of understanding the underlying molecular mechanisms leading to nodulation, many efforts are underway to identify nodulation-related genes and determine how these genes interact with each other. In order to accurately and efficiently reconstruct nodulation gene network, a crowdsourcing platform, CrowdNodNet, was created. The platform implements the jQuery and vis.js JavaScript libraries, so that users are able to interactively visualize and edit the gene network, and easily access the information about the network, e.g. gene lists, gene interactions and gene functional annotations. In addition, all the gene information is written on MediaWiki pages, enabling users to edit and contribute to the network curation. Utilizing the continuously updated, collaboratively written, and community-reviewed Wikipedia model, the platform could, in a short time, become a comprehensive knowledge base of nodulation-related pathways. The platform could also be used for other biological processes, and thus has great potential for integrating and advancing our understanding of the functional genomics and systems biology of any process for any species. The platform is available at http://crowd.bioops.info/ , and the source code can be openly accessed at https://github.com/bioops/crowdnodnet under MIT License.

  1. Evaluación de la diversidad morfológica en Crotalaria incana L. (Fabaceae, Faboideae, una leguminosa silvestre de valor forrajero Evaluation of morphological diversity in Crotalaria incana L. (Fabaceae, Faboideae, a native forage legume

    Directory of Open Access Journals (Sweden)

    A. M. Planchuelo

    2011-06-01

    Full Text Available Crotalaria incana L. es una leguminosa subtropical de valor forrajero. Estudios morfológicos mostraron que las poblaciones cordobesas tienen similitud con C. megapotamica Burkart, endémica de Entre Ríos. Se estudiaron 58 materiales de herbario considerados unidades taxonómicas operacionales (OTUs. Se analizaron 58 caracteres exomorfológicos de los cuales 17 formaron parte de una matriz evaluada mediante análisis multivariado y componentes principales. El fenograma y los componentes principales separan las 58 OTUs en dos grupos diferenciados por la pubescencia, largo y ancho de los folíolos y largo de los pelos. Los caracteres atribuidos a C. megapotamica tienen valor discriminante positivo que no justifica su inclusión en la sinonimia de C. incana, pero a su vez, no tienen una gran significación taxonómica como para que C. megapotamica sea una especie independiente. Se establece que los materiales de Córdoba y de toda la Argentina sean tratados como un complejo taxonómico, denominado Crotalaria incana L. sensu lato. Se recomienda llamar a los grupos identificados como Grupo 1 y Grupo 2, hasta resolver los estatus nomenclaturales mediante estudios de tipos, revisión de nombres científicos y establecimiento de las correctas sinonimias. Se provee descripción morfológica e ilustración de C. incana L. s.l. y se listan los materiales estudiados.Crotalaria incana L. is subtropical forage legume. Morphological studies reveled that the population growing in Cordoba is similar to C. megaponamica Burkart, endemic of Entre Rios. Fifty eight herbarium specimens considered as operational taxonomic units (OTUs were studied. Fifty eight morphological characters were analyzed using statistical techniques and 17 characters were used for cluster and principal component analyses. The phenogram and the principal components separate the 58 OTUs in two groups, identified by characters related with pubescence of vegetative organs, length and width of

  2. Direct detection of radicals in intact soybean nodules

    DEFF Research Database (Denmark)

    Mathieu, C; Moreau, S; Frendo, P

    1998-01-01

    Electron paramagnetic resonance spectroscopy has been employed to examine the nature of the metal ions and radicals present in intact root nodules of soybean plants grown in the absence of nitrate. The spectra obtained from nodules of different ages using this non-invasive technique show dramatic...... differences, suggesting that there are both qualitative and quantitative changes in the metal ion and radical species present. A major component of the spectra obtained from young nodules is assigned to a complex (Lb-NO) of nitric oxide (NO.) with the heme protein leghemoglobin (Lb). This Lb-NO species, which......, results in changes in the EPR spectra, with the loss of the signals from the Lb-NO complex and appearance of absorptions similar to those from untreated senescent nodules. These results suggest that there are characteristic changes in both the metal ion complexes and radicals present in intact root...

  3. Microbial community analysis of field-grown soybeans with different nodulation phenotypes.

    Science.gov (United States)

    Ikeda, Seishi; Rallos, Lynn Esther E; Okubo, Takashi; Eda, Shima; Inaba, Shoko; Mitsui, Hisayuki; Minamisawa, Kiwamu

    2008-09-01

    Microorganisms associated with the stems and roots of nonnodulated (Nod(-)), wild-type nodulated (Nod(+)), and hypernodulated (Nod(++)) soybeans [Glycine max (L.) Merril] were analyzed by ribosomal intergenic transcribed spacer analysis (RISA) and automated RISA (ARISA). RISA of stem samples detected no bands specific to the nodulation phenotype, whereas RISA of root samples revealed differential bands for the nodulation phenotypes. Pseudomonas fluorescens was exclusively associated with Nod(+) soybean roots. Fusarium solani was stably associated with nodulated (Nod(+) and Nod(++)) roots and less abundant in Nod(-) soybeans, whereas the abundance of basidiomycetes was just the opposite. The phylogenetic analyses suggested that these basidiomycetous fungi might represent a root-associated group in the Auriculariales. Principal-component analysis of the ARISA results showed that there was no clear relationship between nodulation phenotype and bacterial community structure in the stem. In contrast, both the bacterial and fungal community structures in the roots were related to nodulation phenotype. The principal-component analysis further suggested that bacterial community structure in roots could be classified into three groups according to the nodulation phenotype (Nod(-), Nod(+), or Nod(++)). The analysis of root samples indicated that the microbial community in Nod(-) soybeans was more similar to that in Nod(++) soybeans than to that in Nod(+) soybeans.

  4. Activation of cell divisions in legume nodulation

    DEFF Research Database (Denmark)

    Nadzieja, Marcin

    Leguminous plants engage into symbiotic relationships with soil bacteria, rhizobia, and develop root nodules. This process initiates with recognition of bacteria derived signalling molecules called nod factors. The subsequent events lead to symbiotic infection and, occurring in parallel, de novo...... was shown to require auxin signalling. Cytokinin, in contrast, exert a negative regulation of bacterial entry into the root. During organogenesis, auxin and cytokinin maxima are known to accompany nodule primordia development and together regulate progression through the cell cycle. Moreover, application...... the two hormones require further investigation. In order to improve understanding in these areas we aimed to develop and characterise hormone and cell division markers in Lotus japonicus. Using the extensive genetic resources available in L. japonicus, these markers may then be used to develop a more...

  5. A salt stress-responsive cytokinin receptor homologue isolated from Medicago sativa nodules.

    Science.gov (United States)

    Coba de la Peña, Teodoro; Cárcamo, Claudia B; Almonacid, Luis; Zaballos, Angel; Lucas, M Mercedes; Balomenos, Dimitrios; Pueyo, José J

    2008-03-01

    A new cytokinin receptor homologue, MsHK1, was isolated from Medicago sativa root nodules. MsHK1 expression was induced in alfalfa seedlings by exogenous application of the cytokinin trans-zeatin. Transcript accumulation was detected in different plant organs. MsHK1 expression was induced by salt stress in alfalfa roots, leaves and nodules, and transcript accumulation in the vascular bundles pointed to a putative role in osmosensing for MsHK1 and/or other close cytokinin receptor homologues. Expression in the meristem and the invasion zone of the nodule suggest a role for cytokinin receptors in cytokinin sensing during nodule cell division and differentiation.

  6. Metabolite profiles of nodulated alfalfa plants indicate that distinct stages of nodule organogenesis are accompanied by global physiological adaptations.

    Science.gov (United States)

    Barsch, Aiko; Tellström, Verena; Patschkowski, Thomas; Küster, Helge; Niehaus, Karsten

    2006-09-01

    An effective symbiosis between Sinorhizobium meliloti and its host plant Medicago sativa is dependent on a balanced physiological interaction enabling the microsymbiont to fix atmospheric nitrogen. Maintenance of the symbiotic interaction is regulated by still poorly understood control mechanisms. A first step toward a better understanding of nodule metabolism was the determination of characteristic metabolites for alfalfa root nodules. Furthermore, nodules arrested at different developmental stages were analyzed in order to address metabolic changes induced during the progression of nodule formation. Metabolite profiles of bacteroid-free pseudonodule extracts indicated that early nodule developmental processes are accompanied by photosynthate translocation but no massive organic acid formation. To determine metabolic adaptations induced by the presence of nonfixing bacteroids, nodules induced by mutant S. meliloti strains lacking the nitrogenase protein were analyzed. The bacteroids are unable to provide ammonium to the host plant, which is metabolically reflected by reduced levels of characteristic amino acids involved in ammonium fixation. Elevated levels of starch and sugars in Fix(-) nodules provide strong evidence that plant sanctions preventing a transformation from a symbiotic to a potentially parasitic interaction are not strictly realized via photosynthate supply. Instead, metabolic and gene expression data indicate that alfalfa plants react to nitrogen-fixation-deficient bacteroids with a decreased organic acid synthesis and an early induction of senescence. Noneffective symbiotic interactions resulting from plants nodulated by mutant rhizobia also are reflected in characteristic metabolic changes in leaves. These are typical for nitrogen deficiency, but also highlight metabolites potentially involved in sensing the N status.

  7. The Lotus japonicus ndx gene family is involved in nodule function and maintenance

    DEFF Research Database (Denmark)

    Grønlund, Mette; Gustafsen, Camilla; Jensen, Dorthe Bødker

    2003-01-01

    To elucidate the function of the ndx homeobox genes during the Rhizobium-legume symbiosis, two Lotus japonicus ndr genes were expressed in the antisense orientation under the control of the nodule-expressed promoter Psenod12 in transgenic Lotus japonicus plants. Many of the transformants obtained...... segregated into plants that failed to sustain proper development and maintenance of root nodules concomitant with down-regulation of the two ndx genes. The root nodules were actively fixing nitrogen 3 weeks after inoculation, but the plants exhibited a stunted growth phenotype. The nodules on such antisense...... supplied to the plants in which the two ndx genes are down-regulated. The results presented here, indicate that the ndx genes play a role in the development of structural nodule features, required for proper gas diffusion into the nodule and/or transport of the assimilated nitrogen to the plant....

  8. Leucoanthocyanidins as intermediates in anthocyanidin biosynthesis in flowers of Matthiola incana R. Br.

    Science.gov (United States)

    Heller, W; Britsch, L; Forkmann, G; Grisebach, H

    1985-02-01

    (+)Leucopelargonidin [(2R,3S,4R)-3,4,5,7,4'-pentahydroxyflavan] and (+)leucocyanidin [(2R,3S,4R)-3,4,5,7,3',4'-hexahydroxyflavan] were synthesized from (+)dihydrokaempferol and (+)dihydroquercetin, respectively, by sodium-borohydride reduction. The chemical and optical purity of these compounds was established by ultraviolet, proton-nuclear-magnetic-resonance, and optical-rotatory-dispersion spectroscopy. Supplementation experiments with these leucoanthocyanidins were carried out with genetically defined acyanic flowers of Matthiola incana. Feeding of leucopelargonidin and leucocyanidin to line 17 (blocked between dihydroflavonols and anthocyanins) and line 18 (blocked in the chalcone-synthase gene) led to formation of the corresponding anthocyanidin 3-O-glucosides, whereas supplementation of line 19 (blocked in a locus other than line 17 between dihydroflavonols and anthocyanins) did not result in anthocyanin synthesis. The conversion of leucopelargonidin into pelargonidin 3-O-glucoside was further confirmed by incorporation of [4-(3)H]leucopelargonidin into pelargonidin derivatives. The results are strong indications for the role of leucoanthocyanidins (flavan-3,4-diols) as intermediates in anthocyanin biosynthesis.

  9. Spontaneous Crotalaria incana poisoning in cattle in the state of Paraná, BrazilIntoxicação espontânea por Crotalaria incana em bovinos no norte do estado do Paraná

    Directory of Open Access Journals (Sweden)

    Ana Paula Frederico Rodrigues Loureiro Bracarense

    2013-05-01

    Full Text Available Plants of genus Crotalaria have been reported as poisonous for many species of domestic animals. The aim of this work is to report, for the first time in Brazil, an outbreak of C. incana poisoning. The outbreak took place in Nova América da Colina County, Northern region of Paraná state, Brazil, causing death of 30 Nelore heifers in a herd of 223 animals, between 3 and 5 years old. The animals were grazing on pasture fully infested with C. incana. The main clinical signs were characteristic of hepatic encephalopathy and consisted of blindness, depression, aggressiveness, recumbency and death in 48 hours. Gama-glutamyltransferase, and alkaline phosphatase activities were increased. The main necropsy findings were liver congestion and evident lobular pattern, increased gall bladder volume and mesentery oedema near gall bladder. Histological exams showed hepatic hemorrhagic centrolobular necrosis, megalocitosis and spongiform degeneration in thalamus. Morbidity and lethality rates were, respectively, 13,45% and 100%. Epidemiological, clinical and pathological findings suggest that C. incana poisoning was the cause of illness. As plantas do gênero Crotalaria têm sido descritas como tóxicas para várias espécies de animais domésticos. O objetivo desse trabalho é relatar, pela primeira vez no Brasil, um surto de intoxicação natural por C. incana. O surto aconteceu no município de Nova América da Colina, mesorregião norte pioneiro do estado do Paraná, causando a morte de 30 animais de um lote de 223 novilhas para engorda, entre três e cinco anos de idade, que estavam em um piquete invadido por C. incana. Os bovinos apresentaram encefalopatia hepática caracterizada por cegueira, depressão e agressividade, evoluindo para a morte em 48 horas. A atividade sérica das enzimas gamaglutamiltransferase e fosfatase alcalina estava aumentada. Congestão hepática e padrão lobular evidente, vesícula biliar aumentada e edema no mesentério pr

  10. Nod factor receptors form heteromeric complexes and are essential for intracellular infection in Medicago nodules

    NARCIS (Netherlands)

    Moling, S.; Pietraszewska-Bogiel, A.; Postma, M.; Fedorova, E.E.; Hink, M.A.; Limpens, E.H.M.; Gadella, T.W.J.; Bisseling, T.

    2014-01-01

    Rhizobial Nod factors are the key signaling molecules in the legume-rhizobium nodule symbiosis. In this study, the role of the Nod factor receptors NOD FACTOR PERCEPTION (NFP) and LYSIN MOTIF RECEPTOR-LIKE KINASE3 (LYK3) in establishing the symbiotic interface in root nodules was investigated. It

  11. Nod factor receptors form heteromeric complexes and are essential for intracellular infection in medicago nodules

    NARCIS (Netherlands)

    Moling, S.; Pietraszewska-Bogiel, A.; Postma, M.; Fedorova, E.; Hink, M.A.; Limpens, E.; Gadella, T.W.J.; Bisseling, T.

    2014-01-01

    Rhizobial Nod factors are the key signaling molecules in the legume-rhizobium nodule symbiosis. In this study, the role of the Nod factor receptors NOD FACTOR PERCEPTION (NFP) and LYSIN MOTIF RECEPTOR-LIKE KINASE3 (LYK3) in establishing the symbiotic interface in root nodules was investigated. It

  12. NODUL TIROID SOLITER

    Directory of Open Access Journals (Sweden)

    I Gusti Ayu Prema Yani Sidemen

    2014-10-01

    Full Text Available Latar Belakang: Nodul tiroid adalah pembengkakan atau massa pada kelenjar tiroid.Pembedahan merupakan pilihan terapi utama, namun pembedahan yang tidak dilakukandengan baik berisiko tinggi mencederai 2 struktur penting, yakni kelenjar paratiroid dannervus rekuren laringeal. Risiko nodul tiroid akan meningkat seiring pertambahan usiadan kurangnya asupan sodium.Insiden terjadinya nodul tiroid lebih sering ditemukanpada laki-laki dan usia di atas 50 tahun, namun pada kasus ini nodul tiroid soliterditemukan pada seorang perempuan dewasa muda sehingga melatar belakangi penulisuntuk mendiskusikan kasus ini dalam laporan kasus.Kasus: Seorang pasien perempuan 32 tahun dengan keluhan tumbuh benjolan padaleher kiri sejak ± 1 tahun yang lalu. Benjolan tersebut dirasakan semakin membesar.Pasien tidak mengeluhkan rasa nyeri di daerah benjolan. Gangguan pada saat makanataupun minum, riwayat sesak, dada berdebar-debar, sering berkeringat, ataupunpenurunan berat badan disangkal. Pada pemeriksaan fisik didapatkan keadaan umumdalam batas normal.  Pada pemeriksaan status lokalis pada region colli anterior lateralsinistra ditemukan massa lunak yang mobile dengan batas tegas dan ukuran ± 3,2 cm x3,4 cm.Hasil: Hasil pemeriksaan patologi anatomi menunjukkan terdapat degenerasi kistikpada massa tiroid tersebut. Pasien kemudian menjalani tindakan pembedahan, yaknitiroidektomi dengan isthmolobectomy. Tiroidektomi dengan teknik diseksi kapsularpada pasien ini berhasil dibuktikan dengan tidak terdapatnya kerusakan pita suara ataukejang pasca operasi.Kesimpulan: Kondisi pasca tiroidektomi dengan teknik diseksi kapsular pada pasien inibaik, tidak terdapat komplikasi kerusakan pita suara dan nervus rekuren laringeal,pasien hidup, dan luka operasi terawat baik.

  13. Enzymatic reduction of (+)-dihydroflavonols to flavan-3,4-cis-diols with flower extracts from Matthiola incana and its role in anthocyanin biosynthesis.

    Science.gov (United States)

    Heller, W; Forkmann, G; Britsch, L; Grisebach, H

    1985-08-01

    A cell-free extract from flowers of Matthiola incana catalyzes a NADPH-dependent stereospecific reduction of (+)-dihydrokaempferol to 3,4-cis-leucopelargonidin (5,7,4'-trihydroxyflavan-3,4-cis-diol). The pH-optimum of this reaction is around 6. The rate of reaction with NADH was about 50% of that found with NADPH. (+)-Dihydroquercetin and (+)-dihydromyricetin were also reduced by the enzyme preparation to the corresponding flavan-3,4-cis-diols. Correlation between the genotype of M. incana and the presence of dihydroflavonol 4-reductase is strong evidence that this enzyme is involved in anthocyanin biosynthesis.

  14. Acropetal Auxin Transport Inhibition Is Involved in Indeterminate But Not Determinate Nodule Formation

    Directory of Open Access Journals (Sweden)

    Jason L. P. Ng

    2018-02-01

    Full Text Available Legumes enter into a symbiotic relationship with nitrogen-fixing rhizobia, leading to nodule development. Two main types of nodules have been widely studied, indeterminate and determinate, which differ in the location of the first cell division in the root cortex, and persistency of the nodule meristem. Here, we compared the control of auxin transport, content, and response during the early stages of indeterminate and determinate nodule development in the model legumes Medicago truncatula and Lotus japonicus, respectively, to investigate whether differences in auxin transport control could explain the differences in the location of cortical cell divisions. While auxin responses were activated in dividing cortical cells during nodulation of both nodule types, auxin (indole-3-acetic acid content at the nodule initiation site was transiently increased in M. truncatula, but transiently reduced in L. japonicus. Root acropetal auxin transport was reduced in M. truncatula at the very start of nodule initiation, in contrast to a prolonged increase in acropetal auxin transport in L. japonicus. The auxin transport inhibitors 2,3,5-triiodobenzoic acid and 1-N-naphthylphthalamic acid (NPA only induced pseudonodules in legume species forming indeterminate nodules, but failed to elicit such structures in a range of species forming determinate nodules. The development of these pseudonodules in M. truncatula exhibited increased auxin responses in a small primordium formed from the pericycle, endodermis, and inner cortex, similar to rhizobia-induced nodule primordia. In contrast, a diffuse cortical auxin response and no associated cortical cell divisions were found in L. japonicus. Collectively, we hypothesize that a step of acropetal auxin transport inhibition is unique to the process of indeterminate nodule development, leading to auxin responses in pericycle, endodermis, and inner cortex cells, while increased auxin responses in outer cortex cells likely

  15. Uridine 5'-diphosphate-xylose: anthocyanidin 3-O-glucose-xylosyltransferase from petals of Matthiola incana R.Br.

    Science.gov (United States)

    Teusch, M

    1986-12-01

    Petals of genetically defined lines of Matthiola incana R.Br. contain a glycosyltransferase which catalyzes the transfer of the xylosyl moiety of uridine 5'-diphosphate-xylose to the glucose of cyanidin 3-glucoside. The enzyme also uses 3-glucosides of pelargonidin and delphinidin, cyanidin 3-(p-coumaroyl)-glucoside and 3-(caffeoyl)-glucoside as substrates. The xylosyltransferase exhibits a pH optimum of 6.5. The enzyme activity depends on the stage of bud and flower development. Accumulation of cyanidin 3-glucoside during flower development is correlated with xylosyltransferase activity.

  16. Competitive nodulation blocking of cv. Afghanistan pea is related to high levels of nodulation factors made by some strains of Rhizobium leguminosarum bv. viciae.

    Science.gov (United States)

    Hogg, Bridget; Davies, Andrea E; Wilson, Karen E; Bisseling, Ton; Downie, J Allan

    2002-01-01

    Cultivar Afghanistan peas are resistant to nodulation by many strains of Rhizobium leguminosarum bv. viciae but are nodulated by strain TOM, which carries the host specificity gene nodX. Some strains that lack nodX can inhibit nodulation of cv. Afghanistan by strain TOM. We present evidence that this "competitive nodulation-blocking" (Cnb) phenotype may result from high levels of Nod factors inhibiting nodulation of cv. Afghanistan peas. The TOM nod gene region (including nodX) is cloned on pIJ1095, and strains (including TOM itself) carrying pIJ1095 nodulate cv. Afghanistan peas very poorly but can nodulate other varieties normally. The presence of pIJ1095, which causes increased levels of Nod factor production, correlates with Cnb. Nodulation of cv. Afghanistan by TOM is also inhibited by a cloned nodD gene that increases nod gene expression and Nod factor production. Nodulation of cv. Afghanistan can be stimulated if nodD on pIJ1095 is mutated, thus severely reducing the level of Nod factor produced. Repression of nod gene expression by nolR eliminates the Cnb phenotype and can stimulate nodulation of cv. Afghanistan. Addition of Nod factors to cv. Afghanistan roots strongly inhibits nodulation. The Cnb+ strains and added Nod factors inhibit infection thread initiation by strain TOM. The sym2A allele determines resistance of cv. Afghanistan to nodulation by strains of R. leguminosarum bv. viciae lacking nodX. We tested whether sym2A is involved in Cnb by using a pea line carrying the sym2A region introgressed from cv. Afghanistan; nodulation in the introgressed line was inhibited by Cnb+ strains. Therefore, the sym2A region has an effect on Cnb, although another locus (or loci) may contribute to the stronger Cnb seen in cv. Afghanistan.

  17. Magnesium-content of Rhizobium nodules in different plants: the importance of magnesium in nitrogen-fixation of nodules.

    Science.gov (United States)

    Kiss, Sandor A; Stefanovits-Bányai, Eva; Takács-Hájos, Maria

    2004-12-01

    Rhizobium bacteria induce nodules (tumors) in roots of leguminous crops that fix nitrogen (N2) from the atmosphere. Trials were carried on in sterile perlite where two species of peas were grown hydroponically, and in two different soil types (brown forest soil and meadow silt soil), in a field where different leguminous plants were chosen for test plants: lupin, soybean, broad-bean, lentil and bean inoculated by Rhizobium bacteria. The Mg-content of the nutrient solution was higher than that of the control, but in the soil tests 1% Mg leaf fertilization was applied after bacterial inoculation. Number, weight and Mg-content of nodules were evaluated using an AAS method compared with the thick and thin hair/roots of the given plant. Our results clearly show that the Mg nutrition treatment increased the number of Rhizobium nodules and their Mg-content, resulting in increased N2-fixation and yield.

  18. Nodulation pattern and biodiversity of rhizobia of some important ...

    African Journals Online (AJOL)

    A collection of 20 root nodule bacteria were isolated from the hitherto unexplored indigenous woody legumes from Ethiopia. Their diversity was evaluated using numerical analyses on different morphological and physiological characteristics. Most of the isolates were found to be slow-growing, sensitive to high concentration ...

  19. Fungi occurring on forests injured by air pollutants in the Upper Silesia and Cracow industrial regions. Pt. 10. Mycoflora of dying young trees of Alnus incana

    Energy Technology Data Exchange (ETDEWEB)

    Domanski, S.; Kowalski, T.

    1987-01-01

    The results of a 10-year study on the mortality of Alnus incana in the Upper Silesia industrial region (Poland) are presented in this paper. Fungi which infected the trees at different stages of the disease were identified. The most common were: Cryptosphora suffusa, Hypoxylon fuscum, Peniophora cinerea, P. erikssonii, Pezicula cinnamomea, Tymipanis alnea, and Valsa diatrypa.

  20. Nodulation and mycorrhization of transgenic soybean after glyphosate application

    Directory of Open Access Journals (Sweden)

    Aloisio Freitas Chagas Junior

    2013-12-01

    Full Text Available The sensitivity of nitrogen-fixing bacteria like Bradyrhizobium spp with in relation to glyphosate can be influenced by the concentration of the herbicide. This study aims to evaluate the effects of two formulations of glyphosate, in two application periods, on nodulation and mycorrhization in a soybean of variety RR P98Y11, using greenhouse, in pots with capacity of 4 L with savanna soils. Six treatments were utilized using Roundup Ultra and Roundup Original with one and two applications, witness without herbicide and witness only with mineral nitrogen, in a completely randomized design. Four evaluations were done, every 15 days, to determine the plant height, shoot and root dry weight, number of nodules, nodule dry weigh and mycorrhizae. It was observed an increase on the number of nodules, with the use of Roundup Ultra until 15 days after the first application. After this period, the witness only with inoculants showed a larger number of nodules. Roundup Ultra had positive influences on the dry weight of nodules, regardless the number of applications. There was no influence of glyphosate formulation considering the mycorrhizal colonization.

  1. Thyroid carcinoma and hot nodule

    Energy Technology Data Exchange (ETDEWEB)

    Fukata, Shuji; Tamai, Hajime; Matsubayashi, Sunao; Nagai, Keisuke; Hirota, Yoshihiko; Matsuzuka, Fumio; Katayama, Shoichi; Kuma, Kanji; Nagataki, Shigenobu

    1987-09-01

    A 70-year-old woman presented with a nodule in the thyroid gland. /sup 131/I scintigraphy of the gland showed a hot nodule. Histology of the resected thyroid revealed a papillary adenocarcinoma. Although a thyroid carcinoma with a hot nodule seen on the radioiodine isotope scan is a very rare occurrence, it is clinically very important because it may indicate a thyroid malignancy.

  2. Waterlogging tolerance, tissue nitrogen and oxygen transport in the forage legume Melilotus siculus: a comparison of nodulated and nitrate-fed plants.

    Science.gov (United States)

    Konnerup, Dennis; Toro, Guillermo; Pedersen, Ole; Colmer, Timothy David

    2018-01-17

    Soil waterlogging adversely impacts most plants. Melilotus siculus is a waterlogging-tolerant annual forage legume, but data were lacking for the effects of root-zone hypoxia on nodulated plants reliant on N2 fixation. The aim was to compare the waterlogging tolerance and physiology of M. siculus reliant on N2 fixation or with access to NO3-. A factorial experiment imposed treatments of water level (drained or waterlogged), rhizobia (nil or inoculated) and mineral N supply (nil or 11 mm NO3-) for 21 d on plants in pots of vermiculite in a glasshouse. Nodulation, shoot and root growth and tissue N were determined. Porosity (gas volume per unit tissue volume) and respiration rates of root tissues and nodules, and O2 microelectrode profiling across nodules, were measured in a second experiment. Plants inoculated with the appropriate rhizobia, Ensifer (syn. Sinorhizobium) medicae, formed nodules. Nodulated plants grew as well as plants fed NO3-, both in drained and waterlogged conditions. The growth and total N content of nodulated plants (without any NO3- supplied) indicated N2 fixation. Respiration rates (mass basis) were highest in nodules and root tips and lowest in basal root tissues. Secondary aerenchyma (phellem) formed along basal root parts and a thin layer of this porous tissue also covered nodules, which together enhanced gas-phase diffusion of O2 to the nodules; O2 was below detection within the infected zone of the nodule interior. Melilotus siculus reliant on N2 fixation grew well both in drained and waterlogged conditions, and had similar tissue N concentrations. In waterlogged conditions the relatively high respiration rates of nodules must rely on O2 movement via the aerenchymatous phellem in hypocotyl, roots and the outer tissue layers of nodules. © The Author(s) 2018. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Growth response of Casuarina equisetifolia Forst. rooted stem ...

    Indian Academy of Sciences (India)

    2013-10-01

    Oct 1, 2013 ... equisetifolia produce root nodules where the bacteria fix atmospheric nitrogen, which is an essential nutrient for all plant metabolic activities. ... decide the effect of Frankia on the efficiency of N uptake of C. equsetifolia rooted stem ... sterile water and 0.2 g of nodule was ground manually in sterile mortar and ...

  4. Characterization of Rhizobium strain isolated from the roots of ...

    African Journals Online (AJOL)

    Trigonella foenumgraecum (fenugreek) is known for its dietary protein source, medicinal properties and symbiotic nitrogen fixation by Rhizobium present in its root nodules. The present study describes the characterization of a Rhizobium strain isolated from root nodules of fenugreek. The Rhizobium isolates were rod ...

  5. PII Overexpression in Lotus japonicus Affects Nodule Activity in Permissive Low-Nitrogen Conditions and Increases Nodule Numbers in High Nitrogen Treated Plants.

    Science.gov (United States)

    D'Apuzzo, Enrica; Valkov, Vladimir Totev; Parlati, Aurora; Omrane, Selim; Barbulova, Ani; Sainz, Maria Martha; Lentini, Marco; Esposito, Sergio; Rogato, Alessandra; Chiurazzi, Maurizio

    2015-04-01

    We report here the first characterization of a GLNB1 gene coding for the PII protein in leguminous plants. The main purpose of this work was the investigation of the possible roles played by this multifunctional protein in nodulation pathways. The Lotus japonicus LjGLB1 gene shows a significant transcriptional regulation during the light-dark cycle and different nitrogen availability, conditions that strongly affect nodule formation, development, and functioning. We also report analysis of the spatial profile of expression of LjGLB1 in root and nodule tissues and of the protein's subcellular localization. Transgenic L. japonicus lines overexpressing the PII protein were obtained and tested for the analysis of the symbiotic responses in different conditions. The uncoupling of PII from its native regulation affects nitrogenase activity and nodule polyamine content. Furthermore, our results suggest the involvement of PII in the signaling of the nitrogen nutritional status affecting the legumes' predisposition for nodule formation.

  6. Lignin modification leads to increased nodule numbers in alfalfa.

    Science.gov (United States)

    Gallego-Giraldo, Lina; Bhattarai, Kishor; Pislariu, Catalina I; Nakashima, Jin; Jikumaru, Yusuke; Kamiya, Yuji; Udvardi, Michael K; Monteros, Maria J; Dixon, Richard A

    2014-03-01

    Reduction of lignin levels in the forage legume alfalfa (Medicago sativa) by down-regulation of the monolignol biosynthetic enzyme hydroxycinnamoyl coenzyme A:shikimate hydroxycinnamoyl transferase (HCT) results in strongly increased digestibility and processing ability of lignocellulose. However, these modifications are often also associated with dwarfing and other changes in plant growth. Given the importance of nitrogen fixation for legume growth, we evaluated the impact of constitutively targeted lignin modification on the belowground organs (roots and nodules) of alfalfa plants. HCT down-regulated alfalfa plants exhibit a striking reduction in root growth accompanied by an unexpected increase in nodule numbers when grown in the greenhouse or in the field. This phenotype is associated with increased levels of gibberellins and certain flavonoid compounds in roots. Although HCT down-regulation reduced biomass yields in both the greenhouse and field experiments, the impact on the allocation of nitrogen to shoots or roots was minimal. It is unlikely, therefore, that the altered growth phenotype of reduced-lignin alfalfa is a direct result of changes in nodulation or nitrogen fixation efficiency. Furthermore, HCT down-regulation has no measurable effect on carbon allocation to roots in either greenhouse or 3-year field trials.

  7. Cowpea and peanut in southern Africa are nodulated by diverse Bradyrhizobium strains harboring nodulation genes that belong to the large pantropical clade common in Africa.

    Science.gov (United States)

    Steenkamp, Emma T; Stepkowski, Tomasz; Przymusiak, Anna; Botha, Wilhelm J; Law, Ian J

    2008-09-01

    Cowpea (Vigna unguiculata) and peanut (Arachis hypogaea) in southern Africa are nodulated by a genetically diverse group of Bradyrhizobium strains. To determine the identity of these bacteria, a collection of 22 isolates originating from the root nodules of both hosts in Botswana and South Africa was investigated using the combined sequences for the core genome genes rrs, recA, and glnII. These data separated the majority of the isolates into one of three unique lineages that most likely represent novel Bradyrhizobium species. Some isolates were also conspecific with B. yuanmingense and with B. elkanii, although none grouped with B. japonicum, B. canariense or B. liaoningense. To study the evolution of nodulation genes in these bacteria, the common nodulation gene, nodA, and host-specific nodulation genes, nodZ, noeE, and noeI, were analyzed. The nodA phylogeny showed that the cowpea and peanut Bradyrhizobium isolates represent various locally adapted groups or ecotypes that form part of Clade III of the seven known BradyrhizobiumnodA clades. This large and highly diverse clade comprises all strains from sub-Saharan Africa, as well as some originating from the Americas, Australia, Indonesia, China and Japan. Some similar groupings were supported by the other nodulation genes, although the overall phylogenies for the nodulation genes were incongruent with that inferred from the core genome genes, suggesting that horizontal gene transfer significantly influences the evolution of cowpea and peanut root-nodule bacteria. Furthermore, identification of the nodZ, noeI, and noeE genes in the isolates tested indicates that African Bradyrhizobium species may produce highly decorated nodulation factors, which potentially represent an important adaptation enabling nodulation of a great variety of legumes inhabiting the African continent.

  8. Species Specific Responses to Age on Nodule Formation, Seedling Growth, and Biomass Production of Acacia auriculiformis at Nursery Stage

    Directory of Open Access Journals (Sweden)

    Md. Salim Azad

    2016-01-01

    Full Text Available Nodulation responses of leguminous trees are very important for intercropping to reduce reliance on artificial nitrogen input through nitrogen fixation in agroforestry system. This study was carried out to evaluate the status of nodulation (i.e., the number of nodules and their shape and size in root and biomass production of plant growth parameters (i.e., number of leaves, shoot height, root biomass, and shoot biomass of A. auriculiformis seedlings. The assessment was conducted 60 days after seed germination. The study revealed significant differences in nodule number per seedling, leaf number per seedling, shoot height, and biomass accumulation (both green and oven dry weight with seedling age (p<0.05. The study also revealed significant correlation among the variables of nodulation responses and biomass production. The results obtained using principal component analysis (PCA justified correlation matrix of nodulation responses and biomass production of this species. The PCA showed that root biomass per seedling, leaf number per seedling, nodule number per seedling, shoot height, age of seedling, and shoot biomass per seedling were clustered with PC1 (with an eigenvalue of 5.59 and root shoot ratios were clustered with PC2 (with an eigenvalue of 1.82. Our study justified that shoot height may be an important determinant of nodule formation of A. auriculiformis.

  9. Medicago truncatula ENOD40-1 and ENOD40-2 are both involved in nodule initiation and bacteroid development

    NARCIS (Netherlands)

    Wan, X.; Hontelez, J.; Lillo, A.; Guarnerio, C.; Peut, van de D.; Fedorova, E.; Bisseling, T.; Franssen, H.

    2007-01-01

    The establishment of a nitrogen-fixing root nodule on legumes requires the induction of mitotic activity of cortical cells leading to the formation of the nodule primordium and the infection process by which the bacteria enter this primordium. Several genes are up-regulated during these processes,

  10. Incorporation of T4 phage DNA into a specific DNA fraction from the higher plant Matthiola incana.

    Science.gov (United States)

    Gradmann-Rebel, W; Hemleben, V

    1976-01-01

    Isolated T4 phage DNA (sigma=1.694 g/ml) is applied to seedlings of the crucifer Matthiola incana (DNA density sigma=1.698 g/ml). The phage DNA can partly be reextracted from the plants in a specific DNA fraction, which is predominantly characterized by its unusual high density (high density complex=HDC; sigma=1.724 g/ml). DNA:DNA hybridization studies show that phage specific DNA sequences are preserved in the HDC. Results of BrdUrd labeling of the plant DNA before and during incubation with T4DNA suggest that the HDC is composed of T4DNA and a plant DNA component of high density. The analysis of ultrasonicated HDC confirms this suggestion. The ability of plant cells to recognize and handle T4 DNA specifically is discussed.

  11. In vitro evaluation of cytotoxic activity of flower, leaf, stem and root extracts of five Artemisia species.

    Science.gov (United States)

    Gordanian, B; Behbahani, M; Carapetian, J; Fazilati, M

    2014-01-01

    The present study was carried out to investigate cytotoxic activity of flower, leaf, stem and root extracts of five Artemisia species against breast cancer cell line (MCF7) and human embryonic kidney normal cell line (HEK293). The studied Artemisia species were A. absinthium, A. vulgaris, A. incana, A. fragrans and A. spicigera. The cytotoxic activity was measured by MTT assay at different concentrations (62.5, 125, 250, 500 μg/ml). Among these five species, methanol extracts of flower, leaf, stem and root of A. absinthium and A. vulgaris exhibited considerable cytotoxic activity. The flower extracts of these two species were found to have higher cytotoxic effect on MCF7 cell with an IC50 value of 221.5 and >500 μg/ml, respectively. Leaf methanol extract of A. incana also showed cytotoxic activity. Cytotoxic activity of different extracts of A. absinthium, A. vulgaris and A. incana against MCF7 was 10%-40% more than HEK293 cells. Not only the extracts of A. spicigera and A. fragrans did not show any cytotoxic effect against both cell lines, but also increased the number of cells. This study revealed that A. absinthium and A. vulgaris may have a great potential to explore new anticancer drugs.

  12. In vitro evaluation of cytotoxic activity of flower, leaf, stem and root extracts of five Artemisia species

    Science.gov (United States)

    Gordanian, B.; Behbahani, M.; Carapetian, J.; Fazilati, M.

    2014-01-01

    The present study was carried out to investigate cytotoxic activity of flower, leaf, stem and root extracts of five Artemisia species against breast cancer cell line (MCF7) and human embryonic kidney normal cell line (HEK293). The studied Artemisia species were A. absinthium, A. vulgaris, A. incana, A. fragrans and A. spicigera. The cytotoxic activity was measured by MTT assay at different concentrations (62.5, 125, 250, 500 μg/ml). Among these five species, methanol extracts of flower, leaf, stem and root of A. absinthium and A. vulgaris exhibited considerable cytotoxic activity. The flower extracts of these two species were found to have higher cytotoxic effect on MCF7 cell with an IC50 value of 221.5 and >500 μg/ml, respectively. Leaf methanol extract of A. incana also showed cytotoxic activity. Cytotoxic activity of different extracts of A. absinthium, A. vulgaris and A. incana against MCF7 was 10%-40% more than HEK293 cells. Not only the extracts of A. spicigera and A. fragrans did not show any cytotoxic effect against both cell lines, but also increased the number of cells. This study revealed that A. absinthium and A. vulgaris may have a great potential to explore new anticancer drugs. PMID:25657777

  13. Toxic effects of low concentrations of Cu on nodulation of cowpea (Vigna unguiculata)

    International Nuclear Information System (INIS)

    Kopittke, Peter M.; Dart, Peter J.; Menzies, Neal W.

    2007-01-01

    Although Cu is phytotoxic at Cu 2+ activities as low as 1-2 μM, the effect of Cu 2+ on the nodulation of legumes has received little attention. The effect of Cu 2+ on nodulation of cowpea (Vigna unguiculata (L.) Walp. cv. Caloona) was examined in a dilute solution culture system utilising a cation exchange resin to buffer solution Cu 2+ . The nodulation process was more sensitive to increasing Cu 2+ activities than both shoot and root growth; whilst a Cu 2+ activity of 1.0 μM corresponded to a 10% reduction in the relative yield of the shoots and roots, a Cu 2+ activity of 0.2 μM corresponded to a 10% reduction in nodulation. This reduction in nodulation with increasing Cu 2+ activity was associated with an inhibition of root hair formation in treatments containing ≥0.77 μM Cu 2+ , rather than to a reduction in the size of the Rhizobium population. - The nodulation process was more sensitive to increasing Cu 2+ activities than either shoot or root growth

  14. Toxic effects of low concentrations of Cu on nodulation of cowpea (Vigna unguiculata)

    Energy Technology Data Exchange (ETDEWEB)

    Kopittke, Peter M. [School of Land and Food Sciences, University of Queensland, St. Lucia, Qld 4072 (Australia)]. E-mail: p.kopittke@uq.edu.au; Dart, Peter J. [School of Land and Food Sciences, University of Queensland, St. Lucia, Qld 4072 (Australia); Menzies, Neal W. [School of Land and Food Sciences, University of Queensland, St. Lucia, Qld 4072 (Australia)

    2007-01-15

    Although Cu is phytotoxic at Cu{sup 2+} activities as low as 1-2 {mu}M, the effect of Cu{sup 2+} on the nodulation of legumes has received little attention. The effect of Cu{sup 2+} on nodulation of cowpea (Vigna unguiculata (L.) Walp. cv. Caloona) was examined in a dilute solution culture system utilising a cation exchange resin to buffer solution Cu{sup 2+}. The nodulation process was more sensitive to increasing Cu{sup 2+} activities than both shoot and root growth; whilst a Cu{sup 2+} activity of 1.0 {mu}M corresponded to a 10% reduction in the relative yield of the shoots and roots, a Cu{sup 2+} activity of 0.2 {mu}M corresponded to a 10% reduction in nodulation. This reduction in nodulation with increasing Cu{sup 2+} activity was associated with an inhibition of root hair formation in treatments containing {>=}0.77 {mu}M Cu{sup 2+}, rather than to a reduction in the size of the Rhizobium population. - The nodulation process was more sensitive to increasing Cu{sup 2+} activities than either shoot or root growth.

  15. Hijacking of leguminous nodulation signaling by the rhizobial type III secretion system.

    Science.gov (United States)

    Okazaki, Shin; Kaneko, Takakazu; Sato, Shusei; Saeki, Kazuhiko

    2013-10-15

    Root-nodule symbiosis between leguminous plants and nitrogen-fixing bacteria (rhizobia) involves molecular communication between the two partners. Key components for the establishment of symbiosis are rhizobium-derived lipochitooligosaccharides (Nod factors; NFs) and their leguminous receptors (NFRs) that initiate nodule development and bacterial entry. Here we demonstrate that the soybean microsymbiont Bradyrhizobium elkanii uses the type III secretion system (T3SS), which is known for its delivery of virulence factors by pathogenic bacteria, to promote symbiosis. Intriguingly, wild-type B. elkanii, but not the T3SS-deficient mutant, was able to form nitrogen-fixing nodules on soybean nfr mutant En1282. Furthermore, even the NF-deficient B. elkanii mutant induced nodules unless T3SS genes were mutated. Transcriptional analysis revealed that expression of the soybean nodulation-specific genes ENOD40 and NIN was increased in the roots of En1282 inoculated with B. elkanii but not with its T3SS mutant, suggesting that T3SS activates host nodulation signaling by bypassing NF recognition. Root-hair curling and infection threads were not observed in the roots of En1282 inoculated with B. elkanii, indicating that T3SS is involved in crack entry or intercellular infection. These findings suggest that B. elkanii has adopted a pathogenic system for activating host symbiosis signaling to promote its infection.

  16. Nodules size: An important factor in nodule mining?

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.

    . In order to minimize ecological and environmental problems, it is emphasized that the nodules should be screened on sea bottom during mining, which may be possible by future technological modification of mining devises...

  17. [Nodulation competitiveness of nodule bacteria: Genetic control and adaptive significance].

    Science.gov (United States)

    Onishchuk, O P; Vorobyov, N I; Provorov, N A

    2017-01-01

    The most recent data on the system of cmp (competitiveness) genes that determine the nodulation competitiveness of rhizobial strains, i.e., the ability to compete for nodule formation in leguminous plants, is analyzed. Three genetic approaches for the construction of economically valuable strains of rhizobia are proposed: the amplification of positive regulators of competitiveness, the inactivation of the negative regulators of this trait, and the introduction of efficient competitiveness factors into strains capable of active nitrogen fixation.

  18. Atividade de enzimas fermentativas em raízes e nódulos de soja sob condições de hipóxia e pós-hipóxia Fermentative enzymes activity in soybean roots and nodules under hypoxia and post-hypoxia conditions

    Directory of Open Access Journals (Sweden)

    Junior Borella

    2013-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a atividade de enzimas fermentativas em raízes e nódulos de soja (Glycine max sob condições de hipóxia e pós-hipóxia. Os genótipos Fundacep 53 RR e BRS Macota foram cultivados em vasos de 3L contendo vermiculita como substrato em associação com Bradyrhizobium elkanii em casa de vegetação. No estádio R2, o sistema radicular das plantas foi submetido à hipóxia pelo encaixe de um segundo vaso sem perfurações e inundado com solução nutritiva diluída a 1/3 da concentração original, por 8 dias. Posteriormente, foram retirados os vasos sem perfurações para avaliação da recuperação. O material vegetal foi coletado no 2º, 4º, 6º e 8º dias após a inundação ou recuperação, juntamente com os controles para a dosagem da atividade das enzimas álcool desidrogenase (ADH, piruvato descarboxilase (PDC e lactato desidrogenase (LDH em raízes e nódulos. Os dados foram submetidos à ANOVA e comparados pelo teste de Tukey a 5% de probabilidade. As atividades da ADH, PDC e LDH foram fortemente estimuladas com a inundação, especialmente em nódulos, e diminuíram com a recuperação, em ambos os genótipos. Fundacep 53 RR respondeu de forma mais efetiva aos efeitos dos tratamentos.This study aimed to evaluate the activity of fermentative enzymes in soybean (Glycine max roots and nodules under hypoxia and post-hypoxia conditions. The soybean genotypes Fundacep 53 RR and BRS Macota associated with Bradyrhizobium elkanii were grown in 3L pots containing vermiculite as substrate under greenhouse conditions. Root system of plants at the R2 stage was subjected to hypoxia by blocking drainage of the pot, by fitting a second one without holes and flooded with nutrient solution diluted one-third of the original. The flooding of the plants was carried out for eight days and after, the pot without drilling was removed for recovery assessment. Non-waterlogged plants were kept as control. Activities of

  19. EFFECT OF PHOSPHATE ON NODULE PRIMORDIA OF SOYBEAN (Glycine max Merrill IN ACID SOILS IN RHIZOTRON EXPERIMENTS

    Directory of Open Access Journals (Sweden)

    Setiyo Hadi Waluyo

    2016-10-01

    Full Text Available To clarify whether P had a direct or indirect effect on the nodulation  process of soybean grown in acid soils from Sitiung, West Sumatra, Indonesia, a series of rhizotron experiments, with special attention given to formation of nodule primordia, was conducted at Laboratory of  Microbiology, Wageningen University in 1998-2000. It was shown that Ca and P were essential nutrients for root growth, nodule formation, and growth of soybean in the acid soils (Oxisols. Ca increased root growth, number of nodule primordia, nodules, and growth of the soybean plant. This positive effect of Ca was increased considerably by the application of P. Ca and P have a synergistic effect on biological nitrogen fixation (BNF of soybean in acid soils. Ca is important for the establishment of nodules, whilst P is essential for the development and function of the formed nodules. P increased number of nodule primordia, thus it also has an important role in the initiation of nodule formation. From this study, it can be concluded that Ca and P are the most limiting nutrients for BNF of soybean in the acid soils of Sitiung, West Sumatra, Indonesia.

  20. Chemical composition and general toxicity of essential oils extracted from the aerial parts of Artemisia armeniaca Lam. and A. incana (L.) Druce growing in Iran.

    Science.gov (United States)

    Mojarrab, M; Delazar, A; Esnaashari, S; Afshar, F Heshmati

    2013-01-01

    The essential oils of the aerial parts of A. armeniaca and A. incana, collected from Arasbaran area (East Azarbaijan province, Iran) were extracted by hydrodistillation and analyzed by GC-MS. In total, 16 and 40 constituents were identified and quantified in the oils of A. armeniaca and A. incana representing 80.5% and 84.6% of the oils, respectively. The essential oil of A. armeniaca was mainly composed of non-terpene hydrocarbons (24.8%). The major components of the oil were α-pinene (10.7%), nonadecane (10.0%), 6,10,14-trimethyl-2-pentadecanone (9.4%), spathulenol (7.8%) and Z-verbenol (5.8%). The essential oil of A. incana was dominated by oxygenated monoterpenes (41.6%), with camphor (20.4%), 1,8-cineol (10.3%), Z-verbenol (8.7%), β-thujone (8.3%) and α-thujone (5.6%), as major components. The essential oils were also subjected to general toxicity assay using brine shrimp lethality method. The toxicity profile of both oils indicated some degree of toxicity in comparison with podophyllotoxin.

  1. The Class II trehalose 6-phosphate synthase gene PvTPS9 modulates trehalose metabolism in Phaseolus vulgaris nodules.

    Directory of Open Access Journals (Sweden)

    Aarón Barraza

    2016-11-01

    Full Text Available Legumes form symbioses with rhizobia, producing nitrogen-fixing nodules on the roots of the plant host. The network of plant signaling pathways affecting carbon metabolism may determine the final number of nodules. The trehalose biosynthetic pathway regulates carbon metabolism and plays a fundamental role in plant growth and development, as well as in plant-microbe interactions. The expression of genes for trehalose synthesis during nodule development suggests that this metabolite may play a role in legume-rhizobia symbiosis. In this work, PvTPS9, which encodes a Class II trehalose-6-phosphate synthase (TPS of common bean (Phaseolus vulgaris, was silenced by RNA interference in transgenic nodules. The silencing of PvTPS9 in root nodules resulted in a reduction of 85% (± 1% of its transcript, which correlated with a 30% decrease in trehalose contents of transgenic nodules and in untransformed leaves. Composite transgenic plants with PvTPS9 silenced in the roots showed no changes in nodule number and nitrogen fixation, but a severe reduction in plant biomass and altered transcript profiles of all Class II TPS genes. Our data suggest that PvTPS9 plays a key role in modulating trehalose metabolism in the symbiotic nodule and, therefore, in the whole plant.

  2. Correlation of arbuscular mycorrhizal colonization with plant growth, nodulation, and shoot npk in legumes

    International Nuclear Information System (INIS)

    Javaid, A.; Anjum, T.; Shah, M.H.M.

    2007-01-01

    Correlation of arbuscular mycorrhizal colonization with different root and shoot growth, nodulation and shoot NPK parameters was studied in three legumes viz. Trifolium alexandrianum, Medicago polymorpha and Melilotus parviflora. The three test legume species showed different patterns of root and shoot growth, nodulation, mycorrhizal colonization and shoot N, P and K content. Different mycorrhizal structures viz. mycelium, arbuscules and vesicles showed different patters of correlation with different studied parameters. Mycelial infection showed an insignificantly positive correlation with root and shoot dry biomass and total root length. Maximum root length was however, negatively associated with mycelial infection. Both arbuscular and vesicular infections were negatively correlated with shoot dry biomass and different parameters of root growth. The association between arbuscular infection and maximum root length was significant. All the three mycorrhizal structures showed a positive correlation with number and biomass of nodules. The association between arbuscular infection and nodule number was significant. Mycelial infection was positively correlated with percentage and total shoot N and P. Similarly percentage N was also positively correlated with arbuscular and vesicular infections. By contrast, total shoot N showed a negative association with arbuscular as well as vesicular infections. Similarly both percentage and total shoot P were negatively correlated with arbuscular and vesicular infections. All the associations between mycorrhizal parameters and shoot K were negative except between vesicular infection and shoot %K. (author)

  3. Hydrogen Reactions of Nodulated Leguminous Plants

    Science.gov (United States)

    Schubert, Karel R.; Engelke, Jean A.; Russell, Sterling A.; Evans, Harold J.

    1977-01-01

    The ATP-dependent evolution of H2 catalyzed by nitrogenase and the hydrogenase-catalyzed oxidation of H2 have been implicated as factors influencing the efficiency of energy utilization in the N2 fixation process. The effects of rhizobial strain and plant age on the H2-evolving and H2-utilizing activity of leguminous root nodules are described in this manuscript. Two classes of legume-Rhizobium combinations were observed in studies with soybeans (Glycine max L. Merr.) and cowpeas (Vigna unguiculata L. Walp.). One group evolved H2 in air; the other group did not exhibit net evolution of H2. The latter group metabolized H2 formed within the nodule through the action of a hydrogenase. The capacity to oxidize H2 was strongly linked to the strain of Rhizobium used to inoculate cowpeas and soybeans. Although the magnitude of H2 evolution in air changed during vegetative growth of a given symbiont, the ratio of H2 evolved in air to total nitrogenase activity was not appreciably altered during this period. No consistent difference in nitrogenase activity as measured by the C2H2 reduction assay was observed between symbionts with an active hydrogenase and those that apparently lack the enzyme and evolve H2. The effects of the two reactions of H2 on total N2 fixation and yield must now be established. PMID:16660157

  4. A Sinorhizobium meliloti-specific N-acyl homoserine lactone quorum-sensing signal increases nodule numbers in Medicago truncatula independent of autoregulation

    Directory of Open Access Journals (Sweden)

    Debora Fabiola Veliz Vallejos

    2014-10-01

    Full Text Available N-acyl homoserine lactones (AHLs act as quorum sensing signals that regulate cell-density dependent behaviors in many gram-negative bacteria, in particular those important for plant-microbe interactions. AHLs can also be recognized by plants, and this may influence their interactions with bacteria. Here we tested whether the exposure to AHLs affects the nodule-forming symbiosis between legume hosts and rhizobia. We treated roots of the model legume, Medicago truncatula, with a range of AHLs either from its specific symbiont, Sinorhizobium meliloti, or from the potential pathogens, Pseudomonas aeruginosa and Agrobacterium vitis. We found increased numbers of nodules formed on root systems treated with the S. meliloti-specific AHL, 3-oxo-C14-homoserine lactone, at a concentration of 1 μM, while the other AHLs did not result in significant changes to nodule numbers. We did not find any evidence for altered nodule invasion by the rhizobia. Quantification of flavonoids that could act as nod gene inducers in S. meliloti did not show any correlation with increased nodule numbers. The effects of AHLs were specific for an increase in nodule numbers, but not lateral root numbers or root length. Increased nodule numbers following 3-oxo-C14-homoserine lactone treatment were under control of autoregulation of nodulation and were still observed in the autoregulation mutant, sunn4 (super numeric nodules4. However, increases in nodule numbers by 3-oxo-C14-homoserine lactone were not found in the ethylene-insensitive sickle mutant. A comparison between M. truncatula with M. sativa (alfalfa and Trifolium repens (white clover showed that the observed effects of AHLs on nodule numbers were specific to M. truncatula, despite M. sativa nodulating with the same symbiont. We conclude that plant perception of the S. meliloti-specific 3-oxo-C14-homoserine lactone influences nodule numbers in M. truncatula via an ethylene-dependent, but autoregulation

  5. Metabolic changes of iron uptake in N(2)-fixing common bean nodules during iron deficiency.

    Science.gov (United States)

    Slatni, Tarek; Vigani, Gianpiero; Salah, Imen Ben; Kouas, Saber; Dell'Orto, Marta; Gouia, Houda; Zocchi, Graziano; Abdelly, Chedly

    2011-08-01

    Iron is an important nutrient in N(2)-fixing legume nodules. The demand for this micronutrient increases during the symbiosis establishment, where the metal is utilized for the synthesis of various iron-containing proteins in both the plant and the bacteroid. Unfortunately, in spite of its importance, iron is poorly available to plant uptake since its solubility is very low when in its oxidized form Fe(III). In the present study, the effect of iron deficiency on the activity of some proteins involved in Strategy I response, such as Fe-chelate reductase (FC-R), H(+)-ATPase, and phosphoenolpyruvate carboxylase (PEPC) and the protein level of iron regulated transporter (IRT1) and H(+)-ATPase proteins has been investigated in both roots and nodules of a tolerant (Flamingo) and a susceptible (Coco blanc) cultivar of common bean plants. The main results of this study show that the symbiotic tolerance of Flamingo can be ascribed to a greater increase in the FC-R and H(+)-ATPase activities in both roots and nodules, leading to a more efficient Fe supply to nodulating tissues. The strong increase in PEPC activity and organic acid content, in the Flamingo root nodules, suggests that under iron deficiency nodules can modify their metabolism in order to sustain those activities necessary to acquire Fe directly from the soil solution. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  6. The nodule conductance to O₂ diffusion increases with phytase activity in N₂-fixing Phaseolus vulgaris L.

    Science.gov (United States)

    Lazali, Mohamed; Drevon, Jean Jacques

    2014-07-01

    To understand the relationship between phosphorus use efficiency (PUE) and respiration for symbiotic nitrogen fixation (SNF) in legume nodules, six recombinant inbred lines of common bean (RIL Phaseolus vulgaris L.), contrasting in PUE for SNF, were inoculated with Rhizobium tropici CIAT899, and grown under hydroaeroponic culture with sufficient versus deficient P supply (250 versus 75 μmol P plant(-1) week(-1)). At the flowering stage, the biomass of plants and phytase activity in nodules were analyzed after measuring O2 uptake by nodulated roots. Our results show that the P-deficiency significantly increased the phytase activity in nodules of all RILs though with highest extent for RILs 147, 29 and 83 (ca 45%). This increase in phytase activity was associated with an increase in nodule respiration (ca 22%) and in use of the rhizobial symbiosis (ca 21%). A significant correlation was found under P-deficiency between nodule O2 permeability and phytase activity in nodules for RILs 104, 34 and 115. This observation is to our knowledge the first description of a correlation between O2 permeability and phytase activity of a legume nodule. It is concluded that the variation of phytase activity in nodules can increase the internal utilization of P and might be involved in the regulation of nodule permeability for the respiration linked with SNF and the adaptation to P-deficiency. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  7. Epidermal and cortical roles of NFP and DMI3 in coordinating early steps of nodulation in Medicago truncatula.

    Science.gov (United States)

    Rival, Pauline; de Billy, Françoise; Bono, Jean-Jacques; Gough, Clare; Rosenberg, Charles; Bensmihen, Sandra

    2012-09-01

    Legumes have evolved the capacity to form a root nodule symbiosis with soil bacteria called rhizobia. The establishment of this symbiosis involves specific developmental events occurring both in the root epidermis (notably bacterial entry) and at a distance in the underlying root cortical cells (notably cell divisions leading to nodule organogenesis). The processes of bacterial entry and nodule organogenesis are tightly linked and both depend on rhizobial production of lipo-chitooligosaccharide molecules called Nod factors. However, how these events are coordinated remains poorly understood. Here, we have addressed the roles of two key symbiotic genes of Medicago truncatula, the lysin motif (LysM) domain-receptor like kinase gene NFP and the calcium- and calmodulin-dependent protein kinase gene DMI3, in the control of both nodule organogenesis and bacterial entry. By complementing mutant plants with corresponding genes expressed either in the epidermis or in the cortex, we have shown that epidermal DMI3, but not NFP, is sufficient for infection thread formation in root hairs. Epidermal NFP is sufficient to induce cortical cell divisions leading to nodule primordia formation, whereas DMI3 is required in both cell layers for these processes. Our results therefore suggest that a signal, produced in the epidermis under the control of NFP and DMI3, is responsible for activating DMI3 in the cortex to trigger nodule organogenesis. We integrate these data to propose a new model for epidermal/cortical crosstalk during early steps of nodulation.

  8. Antisense repression of the Medicago truncatula nodule-enhanced sucrose synthase leads to a handicapped nitrogen fixation mirrored by specific alterations in the symbiotic transcriptome and metabolome.

    Science.gov (United States)

    Baier, Markus C; Barsch, Aiko; Küster, Helge; Hohnjec, Natalija

    2007-12-01

    We analyzed the role of the sucrose (Suc) synthase MtSucS1 during nodulation of the model legume Medicago truncatula, integrating data for the developmental, transcriptional, and metabolic processes affected downstream of an impaired Suc cleavage in root nodules. To reduce carbohydrate supply to nodule tissues, transgenic plants expressing a p35S-driven MtSucS1-antisense fusion were constructed. These plants displayed an up to 90% reduction of MtSucS1 proteins in roots and nodules. Phenotypic studies of two independent MtSucS1-reduced lines demonstrated that only under conditions depending on nodulation, these plants appeared to be impaired in above-ground growth. Specifically plant height, shoot weight, leaf development, flowering, as well as seed maturation were reduced, and the efficiency of photosynthesis was affected. Concomitantly, a significantly enhanced root to shoot ratio with a marked increase in root tip numbers was observed. Root nodule formation was found retarded and the impaired nodulation was accompanied by a less efficient nitrogen (N) acquisition. The decreased total N content of MtSucS1-antisense lines and an enhanced carbon to N ratio in roots, nodules, and shoots correlated with the extent of MtSucS1 knockdown. On the level of transcription, effects of an MtSucS1 reduction were evident for genes representing important nodes of the nodule carbon and N metabolism, while metabolite profiling revealed significantly lower levels of amino acids and their derivatives particularly in strongly MtSucS1-reduced nodules. Our results support the model that nodule-enhanced Suc synthase 1 of the model legume M. truncatula is required for the establishment and maintenance of an efficient N-fixing symbiosis.

  9. Nodule development on the tropical legume Sesbania virgata under flooded and non-flooded conditions.

    Science.gov (United States)

    Bomfeti, C A; Ferreira, P A A; Carvalho, T S; De Rycke, R; Moreira, F M S; Goormachtig, S; Holsters, M

    2013-01-01

    The interaction between the Brazilian pioneer legume Sesbania virgata and its microsymbiont Azorhizobium doebereinerae leads to the formation of nitrogen-fixing nodules on roots that grow either in well-aerated soils or in wetlands. We studied the initiation and development of nodules under these alternative conditions. To this end, light and fluorescence microscopy were used to follow the bacterial colonisation and invasion into the host and, by means of transmission electron microscopy, we could observe the intracellular entry. Under hydroponic conditions, intercellular invasion took place at lateral root bases and mature nodules were round and determinate. However, on roots grown in vermiculite that allows aerated growth, bacteria also entered via root hair invasion and nodules were both of the determinate and indeterminate type. Such versatility in entry and developmental plasticity, as previously described in Sesbania rostrata, enables efficient nodulation in both dry and wet environments and are an important adaptive feature of this group of semi-tropical plants that grow in temporarily flooded habitats. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  10. Red nodule on the breast

    Directory of Open Access Journals (Sweden)

    Roberta Colucci

    2012-01-01

    Full Text Available A 63-year-old woman living in the countryside referred to our department with a 2-month history of a red nodule localized on the right breast. Histological examination, immunohistochemical analyses and serologic evaluation conducted with ELISA and Western blot were performed. Clinical diagnosis of borrelial lymphocytoma was not possible solely on the clinical presentation of a classical nodular form without lymphoadenopathy. An absence of a referred prior tick bite and a previous or concomitant erythema migrans at clinical presentation rendered a more challenging diagnosis. The fact that the patient lived in the countryside, the appearance of the breast nodule in September, and serologic, histologic, and immunohistochemical analysis facilitated the diagnosis of borrelial lymphocytoma. We report this case to highlight the importance of an investigation of Lyme borreliosis when a patient living in the countryside presents with a red nodule of the nipple and areola.

  11. Genetic control of UDP-glucose: anthocyanin 5-O-glucosyltransferase from flowers of Matthiola incana R.Br.

    Science.gov (United States)

    Teusch, M; Forkmann, G; Seyffert, W

    1986-09-01

    In flower extracts of defined genotypes of Matthiola incana, an enzyme was demonstrated which catalyzes the transfer of the glucosyl moiety of uridine 5'-diphosphoglucose (UDPGlc) to the 5-hydroxyl group of pelargonidin and cyanidin 3-glycosides and acylated derivatives. The best substrate for 5-glucosylation is the 3-xylosylglucoside acylated with p-coumarate, followed by the 3-xylosylglucoside and by the acylated (p-coumarate) 3-glucoside. The 3-glucoside itself is a very poor substrate. Besides UDPGlc, thymine 5'-diphosphoglucose is a suitable glucosyl-donor, but with a reduced reaction rate (42%). The anthocyanin 5-O-glucosyltransferase exhibits a pH optimum at 7.5 and is generally inhibited by divalent ions and by ethylenediaminetetraacetic acid and p-chloromercuribenzoate. Investigations on different genotypes showed that the 5-O-glucosyltransferase activity is clearly controlled by the gene l. In confirmation of earlier chemogenetic work, enzyme activity is only present in lines with the wild-type allele l(+). The anthocyanin 5-O-glucosyltransferase activity is strictly correlated with the formation of 5-glucosylated anthocyanins during bud development.

  12. Symbioses with nitrogen-fixing bacteria: nodulation and phylogenetic data across legume genera.

    Science.gov (United States)

    Afkhami, Michelle E; Luke Mahler, D; Burns, Jean H; Weber, Marjorie G; Wojciechowski, Martin F; Sprent, Janet; Strauss, Sharon Y

    2018-02-01

    How species interactions shape global biodiversity and influence diversification is a central - but also data-hungry - question in evolutionary ecology. Microbially based mutualisms are widespread and could cause diversification by ameliorating stress and thus allowing organisms to colonize and adapt to otherwise unsuitable habitats. Yet the role of these interactions in generating species diversity has received limited attention, especially across large taxonomic groups. In the massive angiosperm family Leguminosae, plants often associate with root-nodulating bacteria that ameliorate nutrient stress by fixing atmospheric nitrogen. These symbioses are ecologically-important interactions, influencing community assembly, diversity, and succession, contributing ~100-290 million tons of N annually to natural ecosystems, and enhancing growth of agronomically-important forage and crop plants worldwide. In recent work attempting to determine whether mutualism with N-fixing bacteria led to increased diversification across legumes, we were unable to definitively resolve the relationship between diversification and nodulation. We did, however, succeed in compiling a very large searchable, analysis-ready database of nodulation data for 749 legume genera (98% of Leguminosae genera; LPWG 2017), which, along with associated phylogenetic information, will provide a valuable resource for future work addressing this question and others. For each legume genus, we provide information about the species richness, frequency of nodulation, subfamily association, and topological correspondence with an additional data set of 100 phylogenetic trees curated for database compatibility. We found 386 legume genera were confirmed nodulators (i.e., all species examined for nodulation nodulated), 116 were non-nodulating, four were variable (i.e., containing both confirmed nodulators and confirmed non-nodulators), and 243 had not been examined for nodulation in published studies. Interestingly

  13. A Medicago truncatula mutant hyper-responsive to mycorrhiza and defective for nodulation.

    Science.gov (United States)

    Morandi, Dominique; le Signor, Christine; Gianinazzi-Pearson, Vivienne; Duc, Gérard

    2009-08-01

    One key strategy for the identification of plant genes required for mycorrhizal development is the use of plant mutants affected in mycorrhizal colonisation. In this paper, we report a new Medicago truncatula mutant defective for nodulation but hypermycorrhizal for symbiosis development and response. This mutant, called B9, presents a poor shoot and, especially, root development with short laterals. Inoculation with Glomus intraradices results in significantly higher root colonisation of the mutant than the wild-type genotype A17 (+20% for total root length, +16% for arbuscule frequency in the colonised part of the root, +39% for arbuscule frequency in the total root system). Mycorrhizal effects on shoot and root biomass of B9 plants are about twofold greater than in the wild-type genotype. The B9 mutant of M. truncatula is characterised by considerably higher root concentrations of the phytoestrogen coumestrol and by the novel synthesis of the coumestrol conjugate malonyl glycoside, absent from roots of wild-type plants. In conclusion, this is the first time that a hypermycorrhizal plant mutant affected negatively for nodulation (Myc(++), Nod (-/+) phenotype) is reported. This mutant represents a new tool for the study of plant genes differentially regulating mycorrhiza and nodulation symbioses, in particular, those related to autoregulation mechanisms.

  14. Rhizobium anhuiense sp. nov., isolated from effective nodules of Vicia faba and Pisum sativum.

    Science.gov (United States)

    Zhang, Yu Jing; Zheng, Wen Tao; Everall, Isobel; Young, J Peter W; Zhang, Xiao Xia; Tian, Chang Fu; Sui, Xin Hua; Wang, En Tao; Chen, Wen Xin

    2015-09-01

    Four rhizobia-like strains, isolated from root nodules of Pisum sativum and Vicia faba grown in Anhui and Jiangxi Provinces of China, were grouped into the genus Rhizobium but were distinct from all recognized species of the genus Rhizobium by phylogenetic analysis of 16S rRNA and housekeeping genes. The combined sequences of the housekeeping genes atpD, recA and glnII for strain CCBAU 23252(T) showed 86.9 to 95% similarity to those of known species of the genus Rhizobium. All four strains had nodC and nifH genes and could form effective nodules with Pisum sativum and Vicia faba, and ineffective nodules with Phaseolus vulgaris, but did not nodulate Glycine max, Arachis hypogaea, Medicago sativa, Trifolium repens or Lablab purpureus in cross-nodulation tests. Fatty acid composition, DNA-DNA relatedness and a series of phenotypic tests also separated these strains from members of closely related species. Based on all the evidence, we propose a novel species, Rhizobium anhuiense sp. nov., and designate CCBAU 23252(T) ( = CGMCC 1.12621(T) = LMG 27729(T)) as the type strain. This strain was isolated from a root nodule of Vicia faba and has a DNA G+C content of 61.1 mol% (Tm).

  15. Micromonospora from nitrogen fixing nodules of alfalfa (Medicago sativa L.). A new promising Plant Probiotic Bacteria.

    Science.gov (United States)

    Martínez-Hidalgo, Pilar; Galindo-Villardón, Purificación; Trujillo, Martha E; Igual, José M; Martínez-Molina, Eustoquio

    2014-09-17

    Biotic interactions can improve agricultural productivity without costly and environmentally challenging inputs. Micromonospora strains have recently been reported as natural endophytes of legume nodules but their significance for plant development and productivity has not yet been established. The aim of this study was to determine the diversity and function of Micromonospora isolated from Medicago sativa root nodules. Micromonospora-like strains from field alfalfa nodules were characterized by BOX-PCR fingerprinting and 16S rRNA gene sequencing. The ecological role of the interaction of the 15 selected representative Micromonospora strains was tested in M. sativa. Nodulation, plant growth and nutrition parameters were analyzed. Alfalfa nodules naturally contain abundant and highly diverse populations of Micromonospora, both at the intra- and at interspecific level. Selected Micromonospora isolates significantly increase the nodulation of alfalfa by Ensifer meliloti 1021 and also the efficiency of the plant for nitrogen nutrition. Moreover, they promote aerial growth, the shoot-to-root ratio, and raise the level of essential nutrients. Our results indicate that Micromonospora acts as a Rhizobia Helper Bacteria (RHB) agent and has probiotic effects, promoting plant growth and increasing nutrition efficiency. Its ecological role, biotechnological potential and advantages as a plant probiotic bacterium (PPB) are also discussed.

  16. Studies on Nodulation, Biochemical Analysis and Protein Profiles of Rhizobium Isolated From Indigofera species

    Directory of Open Access Journals (Sweden)

    Kumari, B. S.

    2010-01-01

    Full Text Available Nodulation characteristics in five species of Indigofera viz., I .trita, I. linnaei, I. astragalina, I. parviflora and I. viscosa was studied at regular intervals on the plants raised in garden soil. Among the species studied, highest average number of nodules per plant of 23 with maximum sized nodules of 8.0 mm diameter was observed in I. astragalina. Biochemical analysis of root nodules of I. astragalina revealed that the leghaemoglobin content of nodules and nitrogen content of root, shoot, leaves and nodules were gradually increased up to 60 DAS, and then decreased with increase in age. Rhizobium isolates of five species of Indigofera were isolated and screened for enzymatic activities and total cellular protein profiles. All the five isolates showed nitrate reductase, citrase, tryptophanase and catalase activity while much variation was observed for enzymes like gelatinase, urease, caseinase, lipase, amylase, lysine decarboxylase and protease activities. Among the isolates studied, only the isolate from I. viscosa has the ability to solubilize the insoluble tricalcium phosphate. All the Rhizobium isolates exhibit similarity in protein content, except the isolate from I. viscosa which showed one additional protein band.

  17. Identification and Expression Analysis of Medicago truncatula Isopentenyl Transferase Genes (IPTs Involved in Local and Systemic Control of Nodulation

    Directory of Open Access Journals (Sweden)

    Mahboobeh Azarakhsh

    2018-03-01

    Full Text Available Cytokinins are essential for legume plants to establish a nitrogen-fixing symbiosis with rhizobia. Recently, the expression level of cytokinin biosynthesis IPTs (ISOPENTENYLTRANSFERASES genes was shown to be increased in response to rhizobial inoculation in Lotus japonicus, Medicago truncatula and Pisum sativum. In addition to its well-established positive role in nodule primordium initiation in root cortex, cytokinin negatively regulates infection processes in the epidermis. Moreover, it was reported that shoot-derived cytokinin inhibits the subsequent nodule formation through AON (autoregulation of nodulation pathway. In L. japonicus, LjIPT3 gene was shown to be activated in the shoot phloem via the components of AON system, negatively affecting nodulation. However, in M. truncatula, the detailed analysis of MtIPTs expression, both in roots and shoots, in response to nodulation has not been performed yet, and the link between IPTs and AON has not been studied so far. In this study, we performed an extensive analysis of MtIPTs expression levels in different organs, focusing on the possible role of MtIPTs in nodule development. MtIPTs expression dynamics in inoculated roots suggest that besides its early established role in the nodule primordia development, cytokinin may be also important for later stages of nodulation. According to expression analysis, MtIPT3, MtIPT4, and MtIPT5 are activated in the shoots in response to inoculation. Among these genes, MtIPT3 is the only one the induction of which was not observed in leaves of the sunn-3 mutant defective in CLV1-like kinase, the key component of AON, suggesting that MtIPT3 is activated in the shoots in an AON-dependent manner. Taken together, our findings suggest that MtIPTs are involved in the nodule development at different stages, both locally in inoculated roots and systemically in shoots, where their expression can be activated in an AON-dependent manner.

  18. Host range, symbiotic effectiveness and nodulation competitiveness ...

    African Journals Online (AJOL)

    ERIC-PCR DNA fingerprinting patterns were used to identify the isolates occupying nodules. All the isolates nodulated cowpea, groundnut (Arachis hypogeae) and mungbean (Vigna radiata), but only AII-2-1, AII-3-4 and BIII-2-2 nodulated soybean (Glycine max). Apart from cowpea where all the isolates were effective, there ...

  19. Interaction of a nodule specific, trans-acting factor with distinct DNA elements in the soybean leghaemoglobin Ibc(3) 5' upstream region

    DEFF Research Database (Denmark)

    Jensen, Erik Østergaard; Marcker, Kjeld A; Schell, J

    1988-01-01

    Nuclear extracts from soybean nodules, leaves and roots were used to investigate protein-DNA interactions in the 5' upstream (promoter) region of the soybean leghaemoglobin lbc(3) gene. Two distinct regions were identified which strongly bind a nodule specific factor. A Bal31 deletion analysis...

  20. A Legume TOR Protein Kinase Regulates Rhizobium Symbiosis and Is Essential for Infection and Nodule Development1[OPEN

    Science.gov (United States)

    Blanco, Lourdes; Quinto, Carmen

    2016-01-01

    The target of rapamycin (TOR) protein kinase regulates metabolism, growth, and life span in yeast, animals, and plants in coordination with nutrient status and environmental conditions. The nutrient-dependent nature of TOR functionality makes this kinase a putative regulator of symbiotic associations involving nutrient acquisition. However, TOR’s role in these processes remains to be understood. Here, we uncovered the role of TOR during the bean (Phaseolus vulgaris)-Rhizobium tropici (Rhizobium) symbiotic interaction. TOR was expressed in all tested bean tissues, with higher transcript levels in the root meristems and senesced nodules. We showed TOR promoter expression along the progressing infection thread and in the infected cells of mature nodules. Posttranscriptional gene silencing of TOR using RNA interference (RNAi) showed that this gene is involved in lateral root elongation and root cell organization and also alters the density, size, and number of root hairs. The suppression of TOR transcripts also affected infection thread progression and associated cortical cell divisions, resulting in a drastic reduction of nodule numbers. TOR-RNAi resulted in reduced reactive oxygen species accumulation and altered CyclinD1 and CyclinD3 expression, which are crucial factors for infection thread progression and nodule organogenesis. Enhanced expression of TOR-regulated ATG genes in TOR-RNAi roots suggested that TOR plays a role in the recognition of Rhizobium as a symbiont. Together, these data suggest that TOR plays a vital role in the establishment of root nodule symbiosis in the common bean. PMID:27698253

  1. Molecular Signals Controlling the Inhibition of Nodulation by Nitrate in Medicago truncatula

    Directory of Open Access Journals (Sweden)

    Giel E. van Noorden

    2016-07-01

    Full Text Available The presence of nitrogen inhibits legume nodule formation, but the mechanism of this inhibition is poorly understood. We found that 2.5 mM nitrate and above significantly inhibited nodule initiation but not root hair curling in Medicago trunatula. We analyzed protein abundance in M. truncatula roots after treatment with either 0 or 2.5 mM nitrate in the presence or absence of its symbiont Sinorhizobium meliloti after 1, 2 and 5 days following inoculation. Two-dimensional gel electrophoresis combined with mass spectrometry was used to identify 106 differentially accumulated proteins responding to nitrate addition, inoculation or time point. While flavonoid-related proteins were less abundant in the presence of nitrate, addition of Nod gene-inducing flavonoids to the Sinorhizobium culture did not rescue nodulation. Accumulation of auxin in response to rhizobia, which is also controlled by flavonoids, still occurred in the presence of nitrate, but did not localize to a nodule initiation site. Several of the changes included defense- and redox-related proteins, and visualization of reactive oxygen species indicated that their induction in root hairs following Sinorhizobium inoculation was inhibited by nitrate. In summary, the presence of nitrate appears to inhibit nodulation via multiple pathways, including changes to flavonoid metabolism, defense responses and redox changes.

  2. Allene oxide synthase, allene oxide cyclase and jasmonic acid levels in Lotus japonicus nodules.

    Directory of Open Access Journals (Sweden)

    Anna Zdyb

    Full Text Available Jasmonic acid (JA, its derivatives and its precursor cis-12-oxo phytodienoic acid (OPDA form a group of phytohormones, the jasmonates, representing signal molecules involved in plant stress responses, in the defense against pathogens as well as in development. Elevated levels of JA have been shown to play a role in arbuscular mycorrhiza and in the induction of nitrogen-fixing root nodules. In this study, the gene families of two committed enzymes of the JA biosynthetic pathway, allene oxide synthase (AOS and allene oxide cyclase (AOC, were characterized in the determinate nodule-forming model legume Lotus japonicus JA levels were to be analysed in the course of nodulation. Since in all L. japonicus organs examined, JA levels increased upon mechanical disturbance and wounding, an aeroponic culture system was established to allow for a quick harvest, followed by the analysis of JA levels in whole root and shoot systems. Nodulated plants were compared with non-nodulated plants grown on nitrate or ammonium as N source, respectively, over a five week-period. JA levels turned out to be more or less stable independently of the growth conditions. However, L. japonicus nodules formed on aeroponically grown plants often showed patches of cells with reduced bacteroid density, presumably a stress symptom. Immunolocalization using a heterologous antibody showed that the vascular systems of these nodules also seemed to contain less AOC protein than those of nodules of plants grown in perlite/vermiculite. Hence, aeroponically grown L. japonicus plants are likely to be habituated to stress which could have affected JA levels.

  3. Bacterial-induced calcium oscillations are common to nitrogen-fixing associations of nodulating legumes and non-legumes

    NARCIS (Netherlands)

    Granqvist, E.; Sun, J.; Camp, Op den R.; Pujic, P.; Hill, L.; Normand, P.; Morris, R.J.; Downie, J.A.; Geurts, R.; Oldroyd, G.E.D.

    2015-01-01

    •Plants that form root-nodule symbioses are within a monophyletic ‘nitrogen-fixing’ clade and associated signalling processes are shared with the arbuscular mycorrhizal symbiosis. Central to symbiotic signalling are nuclear-associated oscillations in calcium ions (Ca2+), occurring in the root hairs

  4. A Legume TOR Protein Kinase Regulates Rhizobium Symbiosis and Is Essential for Infection and Nodule Development.

    Science.gov (United States)

    Nanjareddy, Kalpana; Blanco, Lourdes; Arthikala, Manoj-Kumar; Alvarado-Affantranger, Xóchitl; Quinto, Carmen; Sánchez, Federico; Lara, Miguel

    2016-11-01

    The target of rapamycin (TOR) protein kinase regulates metabolism, growth, and life span in yeast, animals, and plants in coordination with nutrient status and environmental conditions. The nutrient-dependent nature of TOR functionality makes this kinase a putative regulator of symbiotic associations involving nutrient acquisition. However, TOR's role in these processes remains to be understood. Here, we uncovered the role of TOR during the bean (Phaseolus vulgaris)-Rhizobium tropici (Rhizobium) symbiotic interaction. TOR was expressed in all tested bean tissues, with higher transcript levels in the root meristems and senesced nodules. We showed TOR promoter expression along the progressing infection thread and in the infected cells of mature nodules. Posttranscriptional gene silencing of TOR using RNA interference (RNAi) showed that this gene is involved in lateral root elongation and root cell organization and also alters the density, size, and number of root hairs. The suppression of TOR transcripts also affected infection thread progression and associated cortical cell divisions, resulting in a drastic reduction of nodule numbers. TOR-RNAi resulted in reduced reactive oxygen species accumulation and altered CyclinD1 and CyclinD3 expression, which are crucial factors for infection thread progression and nodule organogenesis. Enhanced expression of TOR-regulated ATG genes in TOR-RNAi roots suggested that TOR plays a role in the recognition of Rhizobium as a symbiont. Together, these data suggest that TOR plays a vital role in the establishment of root nodule symbiosis in the common bean. © 2016 American Society of Plant Biologists. All Rights Reserved.

  5. Response of hoary alyssum (Berteroa incana L. to UV-B radiation

    Directory of Open Access Journals (Sweden)

    Agnieszka Stokłosa

    2012-12-01

    Full Text Available This greenhouse experiment evaluated the response of hoary alyssum plants, up to the rosette phase, to different levels of UV-B radiation. The experiment was carried out in the chambers, equipped with UV-B lamps, emitting biologically effective UV-B radiation of 0 (control, 4, 6 or 8 kJ. As a result, specific traits of the plants such as: leaf number, lamina length, leaf area, specific leaf weight, relative chlorophyll content and shoot biomass were unaffected by any of the UV-B treatments. Significant reductions in the share of large leaves, leaf stalk length and root biomass were noted for plants growing under 8 kJ UV-BBE.

  6. Automated lung nodule classification following automated nodule detection on CT: A serial approach

    International Nuclear Information System (INIS)

    Armato, Samuel G. III; Altman, Michael B.; Wilkie, Joel; Sone, Shusuke; Li, Feng; Doi, Kunio; Roy, Arunabha S.

    2003-01-01

    We have evaluated the performance of an automated classifier applied to the task of differentiating malignant and benign lung nodules in low-dose helical computed tomography (CT) scans acquired as part of a lung cancer screening program. The nodules classified in this manner were initially identified by our automated lung nodule detection method, so that the output of automated lung nodule detection was used as input to automated lung nodule classification. This study begins to narrow the distinction between the 'detection task' and the 'classification task'. Automated lung nodule detection is based on two- and three-dimensional analyses of the CT image data. Gray-level-thresholding techniques are used to identify initial lung nodule candidates, for which morphological and gray-level features are computed. A rule-based approach is applied to reduce the number of nodule candidates that correspond to non-nodules, and the features of remaining candidates are merged through linear discriminant analysis to obtain final detection results. Automated lung nodule classification merges the features of the lung nodule candidates identified by the detection algorithm that correspond to actual nodules through another linear discriminant classifier to distinguish between malignant and benign nodules. The automated classification method was applied to the computerized detection results obtained from a database of 393 low-dose thoracic CT scans containing 470 confirmed lung nodules (69 malignant and 401 benign nodules). Receiver operating characteristic (ROC) analysis was used to evaluate the ability of the classifier to differentiate between nodule candidates that correspond to malignant nodules and nodule candidates that correspond to benign lesions. The area under the ROC curve for this classification task attained a value of 0.79 during a leave-one-out evaluation

  7. Nodulation of Sesbania Species by Rhizobium (Agrobacterium) Strain IRBG74 and Other Rhizobia

    Science.gov (United States)

    Concatenated sequence analysis with 16S rRNA, rpoB and fusA genes identified a strain (IRBG74) isolated from root nodules of the aquatic legume Sesbania cannabina as a close relative of the plant pathogen Rhizobium radiobacter (syn. Agrobacterium tumefaciens). However, DNA:DNA hybridisation with R. ...

  8. A thaumatin-like protein, Rj4, controls nodule symbiotic specificity in soybean.

    Science.gov (United States)

    Hayashi, Masaki; Shiro, Sokichi; Kanamori, Hiroyuki; Mori-Hosokawa, Satomi; Sasaki-Yamagata, Harumi; Sayama, Takashi; Nishioka, Miki; Takahashi, Masakazu; Ishimoto, Masao; Katayose, Yuichi; Kaga, Akito; Harada, Kyuya; Kouchi, Hiroshi; Saeki, Yuichi; Umehara, Yosuke

    2014-09-01

    Soybeans exhibit a nitrogen-fixing symbiosis with soil bacteria of the genera Bradyrhizobium and Ensifer/Sinorhizobium in a unique organ, the root nodule. It is well known that nodulation of soybean is controlled by several host genes referred to as Rj (rj) genes. Among these genes, a dominant allele, Rj4, restricts nodulation with specific bacterial strains such as B. elkanii USDA61 and B. japonicum Is-34. These incompatible strains fail to invade the host epidermal cells as revealed by observations using DsRed-labeled bacteria. Here, we describe the molecular identification of the Rj4 gene by using map-based cloning with several mapping populations. The Rj4 gene encoded a thaumatin-like protein (TLP) that belongs to pathogenesis-related (PR) protein family 5. In rj4/rj4 genotype soybeans and wild soybeans, we found six missense mutations and two consecutive amino acid deletions in the rj4 gene as compared with the Rj4 allele. We also found, using hairy root transformation, that the rj4/rj4 genotype soybeans were fully complemented by the expression of the Rj4 gene. Whereas the expression of many TLPs and other PR proteins is induced by biotic/abiotic stress, Rj4 gene expression appears to be constitutive in roots including root nodules. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  9. Distinct patterns of symbiosis-related gene expression in actinorhizal nodules from different plant families

    NARCIS (Netherlands)

    Pawlowski, K.; Swensen, S.; Guan, C.; Hadri, A.E.; Berry, A.M.; Bisseling, T.

    2003-01-01

    Phylogenetic analyses suggest that, among the members of the Eurosid I clade, nitrogen-fixing root nodule symbioses developed multiple times independently, four times with rhizobia and four times with the genus Frankia. In order to understand the degree of similarity between symbiotic systems of

  10. Nodulation studies with induced mutants of black gram (Vigna mungo L.)

    International Nuclear Information System (INIS)

    Mahna, S.K.; Garg, Rekha; Parvateesam, M.

    1990-01-01

    Mutation breeding has been widely used to generate genetic variability in plants, but reports of mutations affecting the root system are less common. In the present work, black gram (Vigna mungo L. var T9), has been used for studies on the effect of induced mutations on nodulation patterns

  11. A nodule-specific protein secretory pathway required for nitrogen-fixing symbiosis

    NARCIS (Netherlands)

    Wang, D.; Griffitts, J.; Starker, C.; Fedorova, E.; Limpens, E.H.M.; Ivanov, S.E.; Bisseling, T.; Long, S.

    2010-01-01

    The nitrogen-fixing symbiosis between Sinorhizobium meliloti and its leguminous host plant Medicago truncatula occurs in a specialized root organ called the nodule. Bacteria that are released into plant cells are surrounded by a unique plant membrane compartment termed a symbiosome. We found that in

  12. 10Be in manganese nodules

    International Nuclear Information System (INIS)

    Thomas, J.; Parker, P.; Mangini, A.; Cochran, K.; Turekian, K.; Krishnaswami, S.; Sharma, P.

    1981-01-01

    10 Be (t/sub 1/2) = 1.5 MY) is(formed in the upper atmosphere by cosmic ray spallation on nitrogen and oxygen. It is transported to the earth's surface via precipitation. In the oceans it is eventually associated with solid phases depositing on the ocean floor such as manganese nodules and deep-sea sediments. One of the assumptions that is normally made in analysis of such processes is that 10 Be has been produced at a relatively uniform rate over the pat several million years. If we assume, in addition, that the initial specific concentration of 10 Be as it precipitates with a solid phase is invariant with time, then we would expect that the decrease of the 10 Be concentration as a function of depth in a deep-sea core or in a manganese nodule would provide a record of sediment accumulation rate in the former and of growth rate in the latter. The possibility of using cosmic-ray produced 10 Be for the dating of marine deposits had been proposed 25 years ago by Arnold and Goel et al. The method of analysis used by these investigators, and those subsequently pursuing the problem, was low-level β counting. Though the potential of using 10 Be for dating manganese nodules was explored more than a decade ago, only a few measurements of 10 Be in nodules exist in date. This is largely because of the 10 Be measurements in environmental samples have gained considerable momentum during the past 3 to 4 years, after the development of accelerator mass spectrometry for its determination

  13. Mating-induced sexual inhibition in the jumping spider Servaea incana (Araneae: Salticidae: A fast-acting and long-lasting effect.

    Directory of Open Access Journals (Sweden)

    Vivian Mendez

    Full Text Available Mating-induced sexual inhibition has been studied extensively as an important facet of many insect mating systems but remains little understood in spiders. Once mated, females of many spider species become unreceptive and aggressive toward males, but the speed of onset and persistence of this effect are not known. Addressing this gap, the present study considers (1 mating tendency of virgins, latency to remating, and lifetime mating frequency and (2 how quickly sexual inhibition is expressed after the first mating in female Servaea incana jumping spiders. Encounters between males and females took place in two contexts that simulated locations where mating occurs in nature: in the light away from nests ('in the open' and in low light within the shelter of silken retreats ('at a retreat'. Virgin females exhibited high receptivity levels in both contexts but sexual inhibition was induced immediately after their first copulation. The most common tendency was for just one mating in a lifetime, and few females mated more than twice. Context also had an effect on female mating tendency, as virgin females in the open rejected more males before accepting their first mate than did virgin females in retreats. Considering only those females that did remate, females in the open tended to reject fewer males before remating. Given low levels of female remating, virgin females appear to be at a premium for male reproductive fitness in S. incana jumping spiders and this is a likely explanation for protandry found in nature.

  14. The B-ring hydroxylation pattern of intermediates of anthocyanin synthesis in pelargonidin-and cyanidin-producing lines of Matthiola incana.

    Science.gov (United States)

    Forkmann, G

    1980-03-01

    In flowers of Matthiola incana, the B-ring hydroxylation pattern of anthocyanins is controlled by the locus b. Recessive genotypes produce pelargonidin and genotypes with wild-type alleles cyanidin as the aglycone. Supplementation experiments on acyanic flowers using extracts of pelargonidin-and cyanidin-producing flowers, respectively, showed not only the presence of compounds with a precursor function for anthocyanin synthesis in the cyanic flowers but also differences in the B-ring hydroxylation pattern of these compounds. Chromatographic investigations proved that flavanones and dihydroflavonols occur in extracts of cyanic flowers. Naringenin, dihydrokaempferol, and their 7-glucosides could be demonstrated in all flower extracts, but in extracts of cyanidin-producing flowers, dihydroquercetin and a further 3', 4'-hydroxylated dihydroflavonol, tentatively identified as dihydroquercetin 3-glycoside, were additionally found. In no case, however, could eriodictyol be detected. From these results and from the ready hydroxylation of dihydrokaempferol to dihydroquercetin in a white mutant line of Matthiola incana, it can be concluded that introduction of the 3'-hydroxyl group of anthocyanins is not achieved by specific incorporation of caffeic acid during synthesis of the flavonoid skeleton, but by hydroxylation at the dihydroflavonol stage.

  15. Characterization and structural features of a chalcone synthase mutation in a white-flowering line of Matthiola incana R. Br. (Brassicaceae).

    Science.gov (United States)

    Hemleben, Vera; Dressel, Angela; Epping, Bernhard; Lukacin, Richard; Martens, Stefan; Austin, Michael

    2004-05-01

    For Matthiola incana (Brassicaceae), used as a model system to study biochemical and genetical aspects of anthocyanin biosynthesis, several nearly isogenic colored wild type lines and white-flowering mutant lines are available, each with a specific defect in the genes responsible for anthocyanin production (genes e, f, and g). For gene f supposed to code for chalcone synthase (CHS; EC 2.3.1.74), the key enzyme of the flavonoid/anthocyanin biosynthesis pathway belonging to the group of type III polyketide synthases (PKS), the wild type genomic sequence of M. incana line 04 was determined in comparison to the white-flowering CHS mutant line 18. The type of mutation in the chs gene was characterized as a single nucleotide substitution in a triplet AGG coding for an evolutionary conserved arginine into AGT coding for serine (R72S). Northern blots and RT-PCR demonstrated that the mutated gene is expressed in flower petals. Heterologous expression of the wild type and mutated CHS cDNA in E. Scherichia coli, verified by Western blotting and enzyme assays with various starter molecules, revealed that the mutant protein had no detectable activity, indicating that the strictly conserved arginine residue is essential for the enzymatic reaction. This mutation, which previously was not detected by mutagenic screening, is discussed in the light of structural and functional information on alfalfa CHS and related type III PKS enzymes.

  16. Flavonoids and Auxin Transport Inhibitors Rescue Symbiotic Nodulation in the Medicago truncatula Cytokinin Perception Mutant cre1

    Science.gov (United States)

    Ng, Jason Liang Pin; Hassan, Samira; Truong, Thy T.; Hocart, Charles H.; Laffont, Carole; Frugier, Florian; Mathesius, Ulrike

    2015-01-01

    Initiation of symbiotic nodules in legumes requires cytokinin signaling, but its mechanism of action is largely unknown. Here, we tested whether the failure to initiate nodules in the Medicago truncatula cytokinin perception mutant cre1 (cytokinin response1) is due to its altered ability to regulate auxin transport, auxin accumulation, and induction of flavonoids. We found that in the cre1 mutant, symbiotic rhizobia cannot locally alter acro- and basipetal auxin transport during nodule initiation and that these mutants show reduced auxin (indole-3-acetic acid) accumulation and auxin responses compared with the wild type. Quantification of flavonoids, which can act as endogenous auxin transport inhibitors, showed a deficiency in the induction of free naringenin, isoliquiritigenin, quercetin, and hesperetin in cre1 roots compared with wild-type roots 24 h after inoculation with rhizobia. Coinoculation of roots with rhizobia and the flavonoids naringenin, isoliquiritigenin, and kaempferol, or with the synthetic auxin transport inhibitor 2,3,5,-triiodobenzoic acid, rescued nodulation efficiency in cre1 mutants and allowed auxin transport control in response to rhizobia. Our results suggest that CRE1-dependent cytokinin signaling leads to nodule initiation through the regulation of flavonoid accumulation required for local alteration of polar auxin transport and subsequent auxin accumulation in cortical cells during the early stages of nodulation. PMID:26253705

  17. Short-Term Molecular Acclimation Processes of Legume Nodules to Increased External Oxygen Concentration

    Science.gov (United States)

    Avenhaus, Ulrike; Cabeza, Ricardo A.; Liese, Rebecca; Lingner, Annika; Dittert, Klaus; Salinas-Riester, Gabriela; Pommerenke, Claudia; Schulze, Joachim

    2016-01-01

    Nitrogenase is an oxygen labile enzyme. Microaerobic conditions within the infected zone of nodules are maintained primarily by an oxygen diffusion barrier (ODB) located in the nodule cortex. Flexibility of the ODB is important for the acclimation processes of nodules in response to changes in external oxygen concentration. The hypothesis of the present study was that there are additional molecular mechanisms involved. Nodule activity of Medicago truncatula plants were continuously monitored during a change from 21 to 25 or 30% oxygen around root nodules by measuring nodule H2 evolution. Within about 2 min of the increase in oxygen concentration, a steep decline in nitrogenase activity occurred. A quick recovery commenced about 8 min later. A qPCR-based analysis of the expression of genes for nitrogenase components showed a tendency toward upregulation during the recovery. The recovery resulted in a new constant activity after about 30 min, corresponding to approximately 90% of the pre-treatment level. An RNAseq-based comparative transcriptome profiling of nodules at that point in time revealed that genes for nodule-specific cysteine-rich (NCR) peptides, defensins, leghaemoglobin and chalcone and stilbene synthase were significantly upregulated when considered as a gene family. A gene for a nicotianamine synthase-like protein (Medtr1g084050) showed a strong increase in count number. The gene appears to be of importance for nodule functioning, as evidenced by its consistently high expression in nodules and a strong reaction to various environmental cues that influence nodule activity. A Tnt1-mutant that carries an insert in the coding sequence (cds) of that gene showed reduced nitrogen fixation and less efficient acclimation to an increased external oxygen concentration. It was concluded that sudden increases in oxygen concentration around nodules destroy nitrogenase, which is quickly counteracted by an increased neoformation of the enzyme. This reaction might be

  18. Short-term molecular acclimation processes of legume nodules to increased external oxygen concentration

    Directory of Open Access Journals (Sweden)

    Ulrike eAvenhaus

    2016-01-01

    Full Text Available Nitrogenase is an oxygen labile enzyme. Microaerobic conditions within the infected zone of nodules are maintained primarily by an oxygen diffusion barrier located in the nodule cortex. Flexibility of the oxygen diffusion barrier is important for the acclimation processes of nodules in response to changes in external oxygen concentration. The hypothesis of the present study was that there are additional molecular mechanisms involved. Nodule activity of Medicago truncatula plants were continuously monitored during a change from 21 to 25 or 30 % oxygen around root nodules by measuring nodule H2 evolution. Within about two minutes of the increase in oxygen concentration, a steep decline in nitrogenase activity occurred. A quick recovery commenced about eight minutes later. A qPCR-based analysis of the expression of genes for nitrogenase components showed a tendency towards upregulation during the recovery. The recovery resulted in a new constant activity after about 30 minutes, corresponding to approximately 90 % of the pre-treatment level. An RNAseq-based comparative transcriptome profiling of nodules at that point in time revealed that genes for nodule-specific cysteine-rich (NCR peptides, defensins, leghaemoglobin and chalcone and stilbene synthase were significantly upregulated when considered as a gene family. A gene for a nicotianamine synthase-like protein (Medtr1g084050 showed a strong increase in count number. The gene appears to be of importance for nodule functioning, as evidenced by its consistently high expression in nodules and a strong reaction to various environmental cues that influence nodule activity. A Tnt1-mutant that carries an insert in the coding sequence (cds of that gene showed reduced nitrogen fixation and less efficient acclimation to an increased external oxygen concentration. It was concluded that sudden increases in oxygen concentration around nodules destroy nitrogenase, which is quickly counteracted by an increased

  19. Morphological and genetic characterisation of some lima bean (phaseolus lunatus l.) cultivars and their nodulating rhizobia

    International Nuclear Information System (INIS)

    Kole, E.T.M.

    2014-07-01

    Three major investigations were carried out to assess the morphological traits and nodulation potential of thirteen lima bean cultivars as well as the genetic diversity of rhizobia nodulating these lima bean cultivars. Thirteen lima bean cultivars obtained from the CSIR-PGGRI and various market centres in Ghana were used. The experiment was conducted in pots filled with natural topsoil and arranged in a randomised complete block design (RCBD) with three replicates at the Biotechnology and Nuclear Agriculture Research Institute (BNARI) of the Ghana Atomic Energy Commission (GAEC). The study aimed at obtaining some relevant information on the morphological traits of the lima bean to be improved upon, to evaluate their nodulation tendencies and determine similarities and differences of their nodulating rhizobia. Significant differences were obtained in quantitative characters (leaflet length, leaflet width, pod length, pod width, seed length, seed width, seed weight per 10 seeds and days to 50% emergence), contributing to divergence among the lima bean cultivars. Qualitative traits, however, were mostly similar, with few exceptions such as the flower wing colour, growth habit, leaf shape, main stem pigmentation, pod beak shape, seed secondary colour and seed pattern colour showing divergence among the lima bean cultivars. Two major clusters were joined at the similarity distance of 0.69. Majority of the lima bean cultivars were identified to be of the same morphotype with exception in cultivars M4 and A2. There were no significant differences in mean nodule number, mean effective and non-effective nodule counts. The lima bean cultivar GH 17I4 showed superior performance with respect to nodule number counts, effective nodules, fresh shoot weight and fresh root weight. Additionally lima bean cultivars, M5 and A2 indicated superior radiation use efficiency with total shoot dry matter of 731kg/ha and 704kg/ha respectively. A positive and high correlation existed between

  20. Rhizobial strains exert a major effect on the amino acid composition of alfalfa nodules under NaCl stress.

    Science.gov (United States)

    Bertrand, Annick; Bipfubusa, Marie; Dhont, Catherine; Chalifour, François-P; Drouin, Pascal; Beauchamp, Chantal J

    2016-11-01

    Specific amino acids have protective functions in plants under stress conditions. This study assessed the effects of rhizobial strains on the amino acid composition in alfalfa under salt stress. Two alfalfa cultivars (Medicago sativa L. cv Apica and salt-tolerant cv Halo) in association with two Sinorhizobium meliloti strains with contrasting growth under salt stress (strain A2 and salt-tolerant strain Rm1521) were exposed to different levels of NaCl (0, 20, 40, 80 or 160 mM NaCl) under controlled conditions. We compared root and shoot biomasses, as well as root:shoot ratio for each association under these conditions as indicators of the salt tolerance of the symbiosis. Amino acid concentrations were analyzed in nodules, leaves and roots. The total concentration of free amino acids in nodules was mostly rhizobial-strain dependent while in leaves and roots it was mostly responsive to salt stress. For both cultivars, total and individual concentrations of amino acids including asparagine, proline, glutamine, aspartate, glutamate, γ-aminobutyric acid (GABA), histidine and ornithine were higher in Rm1521 nodules than in A2 nodules. Conversely, lysine and methionine were more abundant in A2 nodules than in Rm1521 nodules. Proline, glutamine, arginine, GABA and histidine substantially accumulated in salt-stressed nodules, suggesting an enhanced production of amino acids associated with osmoregulation, N storage or energy metabolism to counteract salt stress. Combining the salt-tolerant strain Rm1521 and the salt-tolerant cultivar Halo enhanced the root:shoot ratios and amino acid concentrations involved in plant protection which could be in part responsible for the enhancement of salt tolerance in alfalfa. Crown Copyright © 2016. Published by Elsevier Masson SAS. All rights reserved.

  1. NAD1 Controls Defense-Like Responses in Medicago truncatula Symbiotic Nitrogen Fixing Nodules Following Rhizobial Colonization in a BacA-Independent Manner.

    Science.gov (United States)

    Domonkos, Ágota; Kovács, Szilárd; Gombár, Anikó; Kiss, Ernő; Horváth, Beatrix; Kováts, Gyöngyi Z; Farkas, Attila; Tóth, Mónika T; Ayaydin, Ferhan; Bóka, Károly; Fodor, Lili; Ratet, Pascal; Kereszt, Attila; Endre, Gabriella; Kaló, Péter

    2017-12-14

    Legumes form endosymbiotic interaction with host compatible rhizobia, resulting in the development of nitrogen-fixing root nodules. Within symbiotic nodules, rhizobia are intracellularly accommodated in plant-derived membrane compartments, termed symbiosomes. In mature nodule, the massively colonized cells tolerate the existence of rhizobia without manifestation of visible defense responses, indicating the suppression of plant immunity in the nodule in the favur of the symbiotic partner. Medicago truncatula DNF2 (defective in nitrogen fixation 2) and NAD1 (nodules with activated defense 1) genes are essential for the control of plant defense during the colonization of the nitrogen-fixing nodule and are required for bacteroid persistence. The previously identified nodule-specific NAD1 gene encodes a protein of unknown function. Herein, we present the analysis of novel NAD1 mutant alleles to better understand the function of NAD1 in the repression of immune responses in symbiotic nodules. By exploiting the advantage of plant double and rhizobial mutants defective in establishing nitrogen-fixing symbiotic interaction, we show that NAD1 functions following the release of rhizobia from the infection threads and colonization of nodule cells. The suppression of plant defense is self-dependent of the differentiation status of the rhizobia. The corresponding phenotype of nad1 and dnf2 mutants and the similarity in the induction of defense-associated genes in both mutants suggest that NAD1 and DNF2 operate close together in the same pathway controlling defense responses in symbiotic nodules.

  2. Symbiont shift towards Rhizobium nodulation in a group of phylogenetically related Phaseolus species.

    Science.gov (United States)

    Servín-Garcidueñas, Luis E; Zayas-Del Moral, Alejandra; Ormeño-Orrillo, Ernesto; Rogel, Marco A; Delgado-Salinas, Alfonso; Sánchez, Federico; Martínez-Romero, Esperanza

    2014-10-01

    Bean plants from the Phaseolus genus are widely consumed and represent a nitrogen source for human nutrition. They provide biological fertilization by establishing root nodule symbiosis with nitrogen-fixing bacteria. To establish a successful interaction, bean plants and their symbiotic bacteria need to synchronize a proper molecular crosstalk. Within the Phaseolus genus, P. vulgaris has been the prominent species to study nodulation with Rhizobium symbionts. However the Phaseolus genus comprises diverse species whose symbionts have not been analyzed. Here we identified and studied nodule bacteria from representative Phaseolus species not previously analyzed and from all the described wild species related to P. vulgaris. We found Bradyrhizobium in nodules from most species representing all Phaseolus clades except in five phylogenetically related species from the P. vulgaris clade. Therefore we propose that Bradyrhizobium nodulation is common in Phaseolus and that there was a symbiont preference shift to Rhizobium nodulation in few related species. This work sets the basis to further study the genetic basis of this symbiont substitution. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Studies on legume root hair development : correlations with the infection process by Rhizobium bacteria

    NARCIS (Netherlands)

    Mylona, P.

    1996-01-01


    Rhizobia-legume interaction leading to the formation of specific organs, namely root nodules, starts at the epidermis of the root. Bacteria interfere with the develomental programme of the epidermal cells by inducing a number of responses, as new root hair growth, root hair deformation

  4. Antisense Repression of the Medicago truncatula Nodule-Enhanced Sucrose Synthase Leads to a Handicapped Nitrogen Fixation Mirrored by Specific Alterations in the Symbiotic Transcriptome and Metabolome1[W

    Science.gov (United States)

    Baier, Markus C.; Barsch, Aiko; Küster, Helge; Hohnjec, Natalija

    2007-01-01

    We analyzed the role of the sucrose (Suc) synthase MtSucS1 during nodulation of the model legume Medicago truncatula, integrating data for the developmental, transcriptional, and metabolic processes affected downstream of an impaired Suc cleavage in root nodules. To reduce carbohydrate supply to nodule tissues, transgenic plants expressing a p35S-driven MtSucS1-antisense fusion were constructed. These plants displayed an up to 90% reduction of MtSucS1 proteins in roots and nodules. Phenotypic studies of two independent MtSucS1-reduced lines demonstrated that only under conditions depending on nodulation, these plants appeared to be impaired in above-ground growth. Specifically plant height, shoot weight, leaf development, flowering, as well as seed maturation were reduced, and the efficiency of photosynthesis was affected. Concomitantly, a significantly enhanced root to shoot ratio with a marked increase in root tip numbers was observed. Root nodule formation was found retarded and the impaired nodulation was accompanied by a less efficient nitrogen (N) acquisition. The decreased total N content of MtSucS1-antisense lines and an enhanced carbon to N ratio in roots, nodules, and shoots correlated with the extent of MtSucS1 knockdown. On the level of transcription, effects of an MtSucS1 reduction were evident for genes representing important nodes of the nodule carbon and N metabolism, while metabolite profiling revealed significantly lower levels of amino acids and their derivatives particularly in strongly MtSucS1-reduced nodules. Our results support the model that nodule-enhanced Suc synthase 1 of the model legume M. truncatula is required for the establishment and maintenance of an efficient N-fixing symbiosis. PMID:17951459

  5. Pulmonary nodules: detection, assessment, and CAD.

    Science.gov (United States)

    Girvin, Francis; Ko, Jane P

    2008-10-01

    The imaging of pulmonary nodules is an evolving and dynamic field. In this review, we discuss the detection and multitechnique characterization of pulmonary nodules, emphasizing the impact of technological advances on both noninvasive and invasive evaluation and surveillance. The potential contribution of MRI, evolving imaging-guided techniques, and computer applications are also discussed. Advances in MDCT and PET and the potential contribution of fast-imaging MRI sequences and computer applications should continue to improve our evaluation of the solitary pulmonary nodule.

  6. Cytological diagnosis of microfilariae in subcutaneous nodule

    Directory of Open Access Journals (Sweden)

    Narayanan K Panicker

    2012-01-01

    Full Text Available Microfilariaemia presenting with subcutaneous nodule is rare. We report a case of a 22-year-old female patient who presented with a subcutaneous nodule on right forearm. Fine-needle aspiration cytology from the nodule showed many sheathed motile microfilaria on wet mount preparation during day time. Wuchereria loa loa is known to be associated with soft tissue swellings as reported earlier. Nocturnal motility and cytomorphological features differentiate Wuchereria bancrofti from Wuchereria loa loa.

  7. Characterization and expression of chalcone synthase in different genotypes of Matthiola incana R.Br. during flower development.

    Science.gov (United States)

    Rall, S; Hemleben, V

    1984-05-01

    The expression of the key enzyme of flavonoid biosynthesis, chalcone synthase (CHS), has been followed in different genotypes of Matthiola incana R.Br. (Brassicaceae) which are genetically defined with respect to anthocyanin production. Enzyme activity was determined by a radioactive assay in crude flower extracts. The amount of enzyme protein in the developing flower was determined by use of SDS-PAGE, protein blotting, reaction with an antiserum against CHS of parsley (Petroselinum hortense), and PAP staining. The molecular weight of about 41 500 of the CHS subunits corresponds with that obtained from other higher plants. Steps of flower development were subdivided into stages-1,0, I-IV. During flower development of a Matthiola line with coloured petals (line 07) a defined pattern of CHS enzyme production can be observed: At the stage of bud opening (stage 0-I) a dramatic increase of the amount of CHS enzyme prodein in the petals occurs. This is quite different from results obtained with petals of the white flowering mutant line 18 bearing a genetic defect in the gene f coding for CHS. Here a reduced and nearly constant level of CHS enzyme protein can be observed during flower development. This line is most attractive for our studies of the regulation of enzyme synthesis because under stress conditions a slight colouring of the flower petals occurs, which is uniformly distributed and line-specific. This suggests that we are dealing with a CHS mutant producing a rather inactive enzyme protein at a low level. This protein may regain enzyme activity under certain environmental conditions. Preliminary investigations suggest a rather high level of CHS mRNA transcription at the bud opening stage of the flowers. Other white flowering mutant lines, line 17 (genotype ee) and line 19 (gg) with a late block in the flavonoid biosynthesis pathway, exhibit a concomitant reduction of CHS enzyme activity and protein content in comparison to anthocyanin-producing lines with the f(+)f(+)e(+)e(+)g(+)g(+)-genotype.

  8. Cytokinin signaling during root development.

    Science.gov (United States)

    Bishopp, Anthony; Help, Hanna; Helariutta, Ykä

    2009-01-01

    The cytokinin class of phytohormones regulates division and differentiation of plant cells. They are perceived and signaled by a phosphorelay mechanism similar to those observed in prokaryotes. Research into the components of phosphorelay had previously been marred by genetic redundancy. However, recent studies have addressed this with the creation of high-order mutants. In addition, several new elements regulating cytokinin signaling have been identified. This has uncovered many roles in diverse developmental and physiological processes. In this review, we look at these processes specifically in the context of root development. We focus on the formation and maintenance of the root apical meristem, primary and secondary vascular development, lateral root emergence and development, and root nodulation. We believe that the root is an ideal organ with which to investigate cytokinin signaling in a wider context.

  9. Root-nodule bacteria isolated from native Amphithalea ericifolia and ...

    African Journals Online (AJOL)

    Yomi

    2012-01-26

    Jan 26, 2012 ... and Graham, 1991; Foster, 1993; Del Papa et al., 2003;. Kiss et al., 2004; Draghi et al., 2010). In the Cape flats and Cederberg mountains of South. Africa, the soils are extremely high in acidity, ranging from. pH 2.9 to 5.0 (Muofhe and Dakora, 1998); yet they support growth of many native legumes as well ...

  10. effect of exogenous application of rhizopine on lucerne root nodulation

    African Journals Online (AJOL)

    BSN

    Meade, H. M., Long, S. R., Ruvkun, G. B., Brown, S. E., and Ausubel, F. M. (1982). Physical and genetic characterisation of symbiotic and auxotrophic mutants of Rhizobium meliloti induced by transposon Tn5 mutagenesis. Jou ma I of Bacteriology. 149: 114-122. Murphy, P.J., Heycke, N., Banfialvi, Z., Tate, M.E., de Bruijn, ...

  11. De Novo Assembly of the Pea (Pisum sativum L. Nodule Transcriptome

    Directory of Open Access Journals (Sweden)

    Vladimir A. Zhukov

    2015-01-01

    Full Text Available The large size and complexity of the garden pea (Pisum sativum L. genome hamper its sequencing and the discovery of pea gene resources. Although transcriptome sequencing provides extensive information about expressed genes, some tissue-specific transcripts can only be identified from particular organs under appropriate conditions. In this study, we performed RNA sequencing of polyadenylated transcripts from young pea nodules and root tips on an Illumina GAIIx system, followed by de novo transcriptome assembly using the Trinity program. We obtained more than 58,000 and 37,000 contigs from “Nodules” and “Root Tips” assemblies, respectively. The quality of the assemblies was assessed by comparison with pea expressed sequence tags and transcriptome sequencing project data available from NCBI website. The “Nodules” assembly was compared with the “Root Tips” assembly and with pea transcriptome sequencing data from projects indicating tissue specificity. As a result, approximately 13,000 nodule-specific contigs were found and annotated by alignment to known plant protein-coding sequences and by Gene Ontology searching. Of these, 581 sequences were found to possess full CDSs and could thus be considered as novel nodule-specific transcripts of pea. The information about pea nodule-specific gene sequences can be applied for gene-based markers creation, polymorphism studies, and real-time PCR.

  12. Root rots

    Science.gov (United States)

    Kathryn Robbins; Philip M. Wargo

    1989-01-01

    Root rots of central hardwoods are diseases caused by fungi that infect and decay woody roots and sometimes also invade the butt portion of the tree. By killing and decaying roots, root rotting fungi reduce growth, decrease tree vigor, and cause windthrow and death. The most common root diseases of central hardwoods are Armillaria root rot, lnonotus root rot, and...

  13. Strategy for polymetallic nodule mining

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, R.

    'Jrlii, SinL:C tbe economic viahility of deep sCnodules and sulfides are being looked upon as an alternative tu the existing but fast dwindling land rcsourccs. Land reseNcs of... and dcscrib\\:s the approach for delineation of a mine !>itc and collection of baseline dala. 42 tn\\ertUlllQIUII ChaUenaa- VoL 10 N.... 3 • 1990 Criteria for delineation of mine site The term 'minesilc' is defined as an ocean bottom area where underspccifie...

  14. Management of solid pulmonary nodules

    International Nuclear Information System (INIS)

    Poschenrieder, F.; Beyer, L.; Stroszczynski, C.; Hamer, O.W.; Rehbock, B.; Diederich, S.; Wormanns, D.

    2014-01-01

    The increasing availability of computed tomography has meant that the number of incidentally detected solitary pulmonary nodules (SPN) has greatly increased in recent years. A reasonable management of these SPN is necessary in order to firstly be able to detect malignant lesions early on and secondly to avoid upsetting the patient unnecessarily or carrying out further stressful diagnostic procedures. This review article shows how the dignity of SPNs can be estimated and based on this how the management can be accomplished taking established guidelines into consideration. (orig.) [de

  15. Lignin Modification Leads to Increased Nodule Numbers in Alfalfa1[C][W][OPEN

    Science.gov (United States)

    Gallego-Giraldo, Lina; Bhattarai, Kishor; Pislariu, Catalina I.; Nakashima, Jin; Jikumaru, Yusuke; Kamiya, Yuji; Udvardi, Michael K.; Monteros, Maria J.; Dixon, Richard A.

    2014-01-01

    Reduction of lignin levels in the forage legume alfalfa (Medicago sativa) by down-regulation of the monolignol biosynthetic enzyme hydroxycinnamoyl coenzyme A:shikimate hydroxycinnamoyl transferase (HCT) results in strongly increased digestibility and processing ability of lignocellulose. However, these modifications are often also associated with dwarfing and other changes in plant growth. Given the importance of nitrogen fixation for legume growth, we evaluated the impact of constitutively targeted lignin modification on the belowground organs (roots and nodules) of alfalfa plants. HCT down-regulated alfalfa plants exhibit a striking reduction in root growth accompanied by an unexpected increase in nodule numbers when grown in the greenhouse or in the field. This phenotype is associated with increased levels of gibberellins and certain flavonoid compounds in roots. Although HCT down-regulation reduced biomass yields in both the greenhouse and field experiments, the impact on the allocation of nitrogen to shoots or roots was minimal. It is unlikely, therefore, that the altered growth phenotype of reduced-lignin alfalfa is a direct result of changes in nodulation or nitrogen fixation efficiency. Furthermore, HCT down-regulation has no measurable effect on carbon allocation to roots in either greenhouse or 3-year field trials. PMID:24406794

  16. Field Phenotyping of Soybean Roots for Drought Stress Tolerance

    Directory of Open Access Journals (Sweden)

    Berhanu A. Fenta

    2014-08-01

    Full Text Available Root architecture was determined together with shoot parameters under well watered and drought conditions in the field in three soybean cultivars (A5409RG, Jackson and Prima 2000. Morphology parameters were used to classify the cultivars into different root phenotypes that could be important in conferring drought tolerance traits. A5409RG is a drought-sensitive cultivar with a shallow root phenotype and a root angle of <40°. In contrast, Jackson is a drought-escaping cultivar. It has a deep rooting phenotype with a root angle of >60°. Prima 2000 is an intermediate drought-tolerant cultivar with a root angle of 40°–60°. It has an intermediate root phenotype. Prima 2000 was the best performing cultivar under drought stress, having the greatest shoot biomass and grain yield under limited water availability. It had abundant root nodules even under drought conditions. A positive correlation was observed between nodule size, above-ground biomass and seed yield under well-watered and drought conditions. These findings demonstrate that root system phenotyping using markers that are easy-to-apply under field conditions can be used to determine genotypic differences in drought tolerance in soybean. The strong association between root and nodule parameters and whole plant productivity demonstrates the potential application of simple root phenotypic markers in screening for drought tolerance in soybean.

  17. Indeterminate Pulmonary Nodules at Colorectal Cancer Staging

    DEFF Research Database (Denmark)

    Nordholm-Carstensen, Andreas; Wille-Jørgensen, Peer A; Jorgensen, Lars N

    2013-01-01

    This study aimed to estimate the prevalence of indeterminate pulmonary nodules and specific radiological and clinical characteristics that predict malignancy of these at initial staging chest computed tomography (CT) in patients with colorectal cancer. A considerable number of indeterminate...... pulmonary nodules, which cannot readily be classified as either benign or malignant, are detected at initial staging chest CT in colorectal cancer patients....

  18. Position of solitary thyroid nodules by gammagraphy

    International Nuclear Information System (INIS)

    Basteris M, J.; Gomez D, R.

    2007-01-01

    In this work it is presented which it is the position more frequent of the solitary thyroid nodules. It was used the method of retrospective longitudinal observational investigation in 125 patients that went to the laboratory for realization of detection of thyroid nodules in the years 2004 and 2005 through gammagraphy. (Author)

  19. Benign solitary solid cold thyroid nodules

    DEFF Research Database (Denmark)

    Døssing, Helle; Bennedbaek, Finn Noe; Karstrup, Steen

    2002-01-01

    PURPOSE: To evaluate the effects of ultrasonography (US)-guided interstitial laser photocoagulation (ILP) on the volume of benign solitary solid cold thyroid nodules and any nodule-related symptoms. MATERIALS AND METHODS: ILP was performed in 16 patients with normal thyroid function and a solid...... benign thyroid nodule. None of the patients had uptake on a radionuclide scan. Patients underwent one ILP session. A needle was positioned in the thyroid nodule with US guidance, and the laser fiber was placed in the lumen of the needle. Patients were treated for 287-1,200 seconds with an output power...... of 1-3 W. ILP was performed with continuous US guidance and terminated when the echogenic changes were stationary. Thyroid nodule volume and thyroid function were evaluated before and 1, 3, and 6 months after treatment. During the same period, 15 untreated patients (control group) were followed up...

  20. Rhizobium NodB protein involved in nodulation signal synthesis is a chitooligosaccharide deacetylase.

    Science.gov (United States)

    John, M; Röhrig, H; Schmidt, J; Wieneke, U; Schell, J

    1993-01-15

    The common nodulation genes nodABC are conserved in all rhizobia and are involved in synthesis of a lipooligosaccharide signal molecule. This bacterial signal consists of a chitooligosaccharide backbone, which carries at the nonreducing end a fatty acyl chain. The modified chitooligosaccharide molecule triggers development of nodules on the roots of the leguminous host plant. To elucidate the specific role of the NodB protein in nodulation factor synthesis, we have purified recombinant NodB and determined its biochemical role by direct assays. Our data show that the NodB protein of Rhizobium meliloti deacetylates the nonreducing N-acetylglucosamine residue of chitooligosaccharides. The monosaccharide N-acetylglucosamine is not deacetylated by NodB. In the pathway of Nod factor synthesis, deacetylation at the nonreducing end of the oligosaccharide backbone may be a necessary requirement for attachment of the fatty acyl chain.

  1. A nodule-specific protein secretory pathway required for nitrogen-fixing symbiosis.

    Science.gov (United States)

    Wang, Dong; Griffitts, Joel; Starker, Colby; Fedorova, Elena; Limpens, Erik; Ivanov, Sergey; Bisseling, Ton; Long, Sharon

    2010-02-26

    The nitrogen-fixing symbiosis between Sinorhizobium meliloti and its leguminous host plant Medicago truncatula occurs in a specialized root organ called the nodule. Bacteria that are released into plant cells are surrounded by a unique plant membrane compartment termed a symbiosome. We found that in the symbiosis-defective dnf1 mutant of M. truncatula, bacteroid and symbiosome development are blocked. We identified the DNF1 gene as encoding a subunit of a signal peptidase complex that is highly expressed in nodules. By analyzing data from whole-genome expression analysis, we propose that correct symbiosome development in M. truncatula requires the orderly secretion of protein constituents through coordinated up-regulation of a nodule-specific pathway exemplified by DNF1.

  2. Sequence organization and putative regulatory elements in the 5S rRNA genes of two higher plants (Vigna radiata and Matthiola incana).

    Science.gov (United States)

    Hemleben, V; Werts, D

    1988-01-01

    The tandemly arranged and clustered highly repeated 5S rRNA genes are investigated for two plants belonging to different higher plant families: Matthiola incana (Brassicaceae, Dilleniidae, Rosidae; 3600 5S rRNA genes/n) shows a homogeneous repeat size of 510 bp, whereas Vigna radiata (mung bean, former Phaseolus aureus, Fabaceae, Rosidae; approx. 4300 5S rRNA genes) has a repeat size of 215 bp. The mung-bean 5S rRNA coding region starts 5' with AGG and ends with CCT; Matthiola starts with GGG and ends with CCC. Striking is the strict occurrence of a 'TATA' box starting at nucleotide-28 similar to Neurospora crassa 5S rRNA genes. The 3' end is followed by CTTTT or GTTT stretches present in different numbers in the non-transcribed spacer suggesting a function in termination.

  3. Transparent Testa Glabra 1 (TTG1) and TTG1-like genes in Matthiola incana R. Br. and related Brassicaceae and mutation in the WD-40 motif.

    Science.gov (United States)

    Dressel, A; Hemleben, V

    2009-03-01

    TTG1 (Transparent Testa Glabra 1), a WD-40 repeat protein, is involved in regulation of flavonoid/anthocyanin biosynthesis, seed coat (mucilage) development/pigmentation and trichome formation in leaves. Here, we characterized the TTG1 gene of Matthiola incana wild type (e locus), showing 85.3% similarity to TTG1 of A. thaliana on the nucleotide level and 96.2% on the protein level. A white-flowered and glabrous mutant, line 17, of M. incana exhibits one nucleotide change, leading to an amino acid substitution directly in the WD motif (W158R). Correspondingly, the DFR (dihydroflavonol 4-reductase) gene, in which the expression is known to be dependent on TTG1, is not expressed in Matthiola mutant lines 17 (and 19). Comparison of the GC content of the Matthiola TTG1 (54.1%) and Arabidopsis TTG1 (46.1%) genes revealed a strong difference, mostly obtained by neutral substitutions (C to T transitions). To examine whether this is an ecologically influenced trend, a fragment of TTG1 was characterized from another Matthiola species (M. tricuspidata) and from Malcolmia flexuosa subsp. naxensis from the eastern Mediterranean, near a beach with sandy and salty soils. Both Matthiola species have a higher GC content in the TTG1 gene than Arabidopsis and the closer-related Malcolmia, indicating that the GC content is rather an evolutionary than an ecological signal. A similar WD-40 repeat protein gene (containing no intron in the 3' untranslated region) with high similarity to the Arabidopsis TTG1-like (AtAN11) gene was found in Matthiola.

  4. Simulation of quantitative characters by genes with biochemically definable action. III. The components of genetic effects in the inheritance of anthocyanins in Matthiola incana R. Br.

    Science.gov (United States)

    Jana, S; Seyffert, W

    1971-01-01

    In a self-pollinated plant species, Matthiola incana R. Br., six groups of isogenic lines were developed which were ideally suited for investigating the properties of individual genes controlling a quantitative character. Each group consisted of four homozygous parents for two alleles at each of the two loci in a common genetic background. A complete 4 × 4 diallel cross was obtained in each group. Because of the identical genetic background each diallel set could be considered as a genetic system of two loci. The biochemical functions of the alleles at each locus modifying the structure of the anthocyanin molecule were known. The phenotypes of the nine possible genotypes were qualitatively distinguishable by their flower colour differences. A quantitative measure of the phenotypic value associated with a genotype is the concentration of anthocyanins in flower tissues. In these simplified genetic systems, the nine phenotypic values could be expressed in terms of nine biometrical quantities, eight of which are attributable to the genetic effects of the alleles at the two loci under consideration. An unique solution of the set of nine equations in nine unknowns provided direct estimates of the parameters specifying additive, dominance and epistatic effects. Thus the effects of individual genes in a well-defined genetic background could be estimated by the use of a simple additive genetic model. An extension of the model provided estimates of the genetic parameters in different years and genetic backgrounds.Dominance was found to be the most important type of gene action in the inheritance of anthocyanin content in the flower tissues of M. incana. There was considerable epistasis, but the effect was very unstable over years and genetic backgrounds. The relative magnitude of additive effect was most stable. Heterosis was observed and was found to be largely due to dominance and additive × dominance interactions.

  5. Nodulation in Dimorphandra wilsonii Rizz. (Caesalpinioideae), a Threatened Species Native to the Brazilian Cerrado

    Science.gov (United States)

    Fonseca, Márcia Bacelar; Peix, Alvaro; de Faria, Sergio Miana; Mateos, Pedro F.; Rivera, Lina P.; Simões-Araujo, Jean L.; França, Marcel Giovanni Costa; dos Santos Isaias, Rosy Mary; Cruz, Cristina; Velázquez, Encarna; Scotti, Maria Rita; Sprent, Janet I.; James, Euan K.

    2012-01-01

    The threatened caesalpinioid legume Dimorphandra wilsonii, which is native to the Cerrado biome in Brazil, was examined for its nodulation and N2-fixing ability, and was compared with another, less-threatened species, D. jorgei. Nodulation and potential N2 fixation was shown on seedlings that had been inoculated singly with five bradyrhizobial isolates from mature D. wilsonii nodules. The infection of D. wilsonii by two of these strains (Dw10.1, Dw12.5) was followed in detail using light and transmission electron microscopy, and was compared with that of D. jorgei by Bradyrhizobium strain SEMIA6099. The roots of D. wilsonii were infected via small transient root hairs at 42 d after inoculation (dai), and nodules were sufficiently mature at 63 dai to express nitrogenase protein. Similar infection and nodule developmental processes were observed in D. jorgei. The bacteroids in mature Dimorphandra nodules were enclosed in plant cell wall material containing a homogalacturonan (pectic) epitope that was recognized by the monoclonal antibody JIM5. Analysis of sequences of their rrs (16S rRNA) genes and their ITS regions showed that the five D. wilsonii strains, although related to SEMIA6099, may constitute five undescribed species of genus Bradyrhizobium, whilst their nodD and nifH gene sequences showed that they formed clearly separated branches from other rhizobial strains. This is the first study to describe in full the N2-fixing symbiotic interaction between defined rhizobial strains and legumes in the sub-family Caesalpinioideae. This information will hopefully assist in the conservation of the threatened species D. wilsonii. PMID:23185349

  6. Early responses to Nod factors and mycorrhizal colonization in a non-nodulating Phaseolus vulgaris mutant.

    Science.gov (United States)

    Cárdenas, Luis; Alemán, Emilia; Nava, Noreide; Santana, Olivia; Sánchez, Federico; Quinto, Carmen

    2006-03-01

    Legumes can acquire nitrogen through a symbiotic interaction with rhizobial bacteria. The initiation of this process is determined by a molecular dialogue between the two partners. Legume roots exude flavonoids that induce the expression of the bacterial nodulation genes, which encode proteins involved in the synthesis and secretion of signals called Nod factors (NFs). NFs signal back to the plant root and trigger several responses, leading to bacterial invasion and nodule formation. Here, we describe the molecular and cellular characterization of a Phaseolus vulgaris non-nodulating mutant (NN-mutant). Root hair cells of the NN-mutant plant respond with swelling and branching when inoculated with Rhizobium etli, albeit without curling induction. Furthermore, neither initiation of cell division in the outer cortex, nor entrapment of bacteria nor infection thread formation was observed. Both the bean wild-type and the NN-mutant responded with elevated intracellular calcium changes in the root hairs. Although the NN-mutant is deficient in early nodulin gene expression when inoculated with R. etli, it can be effectively colonized by arbuscular mycorrhizal fungi (Glomus intraradices). Our data indicate that the P. vulgaris NN-mutant is not blocked at the NFs early perception stage, but at later downstream stages between Ca(2+) signaling and early nodulin induction. This supports the idea that both microsymbionts are perceived and trigger different downstream pathways in the host plant.

  7. The Carbon-Nitrogen Balance of the Nodule and Its Regulation under Elevated Carbon Dioxide Concentration

    Directory of Open Access Journals (Sweden)

    Marc Libault

    2014-01-01

    Full Text Available Legumes have developed a unique way to interact with bacteria: in addition to preventing infection from pathogenic bacteria like any other plant, legumes also developed a mutualistic symbiotic relationship with one gender of soil bacteria: rhizobium. This interaction leads to the development of a new root organ, the nodule, where the differentiated bacteria fix for the plant the atmospheric dinitrogen (atmN2. In exchange, the symbiont will benefit from a permanent source of carbon compounds, products of the photosynthesis. The substantial amounts of fixed carbon dioxide dedicated to the symbiont imposed to the plant a tight regulation of the nodulation process to balance carbon and nitrogen incomes and outcomes. Climate change including the increase of the concentration of the atmospheric carbon dioxide is going to modify the rates of plant photosynthesis, the balance between nitrogen and carbon, and, as a consequence, the regulatory mechanisms of the nodulation process. This review focuses on the regulatory mechanisms controlling carbon/nitrogen balances in the context of legume nodulation and discusses how the change in atmospheric carbon dioxide concentration could affect nodulation efficiency.

  8. [Analysis of Symbiotic Genes of Leguminous Plants Nodule Bacteria Grown in the Southern Urals].

    Science.gov (United States)

    Baymiev, An Kh; Ivanova, E S; Gumenko, R S; Chubukova, O V; Baymiev, Al Kh

    2015-12-01

    Bacterial strains isolated from the nodules, tissues, and root surface of wild legumes growing in the Southern Urals related to the tribes Galegeae, Hedysareae, Genisteae, Trifolieae, and Loteae were examined for the presence in their genomes of symbiotic (sym) genes. It was found that the sym-genes are present in microorganisms isolated only from the nodules of the analyzed plants (sym+ -strains). Phylogenetic analysis of sym+ -strains on the basis of a comparative analysis of 16S rRNA gene sequences showed that sym+ -strains belong to five families of nodule bacteria: Mesorhizobium, Bradyrhizobium, Sinorhizobium, Rhizobium, and Phyllobacterium. A study the phylogeny of the sym-genes showed that the nodule bacteria of leguminous plants of the Southern Urals at the genus level are mainly characterized by a parallel evolution of symbiotic genes and the 16S rRNA gene. Thus, cases of horizontal transfer of sym genes, which sometimes leads to the formation of certain types of atypical rhizobial strains ofleguminous plants, are detected in nodule bacteria populations.

  9. Molecular diversity of rhizobia nodulating the invasive legume Cytisus scoparius in Australia.

    Science.gov (United States)

    Lafay, B; Burdon, J J

    2006-06-01

    To contribute to the understanding of Cytisus scoparius success at invading and establishing itself in Australia. Root-nodule bacteria isolated from C. scoparius, growing on five different sites and originally introduced to Australia, were compared with isolates from indigenous plants growing in France and isolates from native legumes growing on the same Australian sites as C. scoparius. Small-subunit rDNA from 251 isolates were analysed by PCR-RFLP and representatives from different genospecies were selected for sequencing. Phylogenetic analyses revealed a great diversity of lineages belonging to Bradyrhizobium, with one genospecies being specific for Cytisus both in Australia and in France, Rhizobium and Mesorhizobium and one falling outside the described genera of legume-nodulating bacteria. Principal component analysis showed that the Cytisus Australian rhizobial communities are more similar to each other than to their co-occurring native partners. Early established rhizobial symbionts may have an increased probability to contribute inoculum for the development of further nodules. This is a first report comparing rhizobia nodulating C. scoparius in its native and exotic environments. Cytisus scoparius symbionts were identified outside the Bradyrhizobium genus and a new lineage of legume-nodulating bacteria was identified.

  10. Nitrogen assimilation in soybean nodules, 1

    International Nuclear Information System (INIS)

    Ohyama, Takuji; Kumazawa, Kikuo

    1980-01-01

    In order to elucidate the pathways to assimilate the ammonia produced by N 2 -fixation in soybean nodules, 15 N-labeled compounds were administered to intact nodules or nodule slices pretreated with various inhibitors of nitrogen assimilation. After exposure to 15 N 2 , 15 N-incorporation into various nitrogenous compounds was investigated in attached nodules injected with methionine sulfoximine (MSX) or azaserine (AS). MSX treatment increased the 15 N content of ammonia more than 6 times, however, depressed 15 N content of most of amides and amino acids. AS treatment enhanced 15 N content of amido-N of glutamine as well as ammonia, but decreased amino-N of glutamine and most of amino acids. Experiments with nodule slices pretreated with MSX or AS solution and then fed with 15 N-labeled ammonia or amido- 15 N of glutamine showed the same trends. Aminooxyacetate inhibited nitrogen flow from glutamic acid to other amino acids. These results strongly indicate that the ammonia produced by N 2 -fixation is assimilated by GS/GOGAT system to glutamic acid and then transaminated to various amino acids in situ. 15 N-incorporation patterns in nodule slices fed with 15 N-labeled ammonia, hydroxylamine, nitrite were similar, but nitrate seemed to be reduced in a definite compartment and assimilated similarly as in intact nodules fed with 15 N 2 (author)

  11. Management of a solitary thyroid nodule

    International Nuclear Information System (INIS)

    Rao, R.S.

    1999-01-01

    Solitary nodule in the thyroid is a common clinical entity. A careful clinical assessment is the crucial first step in deciding the modality of treatment. The only worthwhile investigation is FNAC. Other investigations are done merely for the sake of a complete academic work up and can usually be dispensed with in most of the cases. Not every solitary nodule requires surgery. The optimum surgery for a solitary nodule is a total lobectomy. The specimen should be subjected to histological examination before recommending further treatment

  12. [Nodules on localized scleroderma or morphea].

    Science.gov (United States)

    Bayle, P; Bazex, J; Marguery, M-C; Lamant, L

    2005-02-01

    Localized scleroderma or morphea usually appears as flat or depressed lesions. We report 3 cases of morphea with atypical appearance, alternating pigmented and depigmented patches with nodules or sclerous bands, occurring in adult men. The occurrence of nodular elements on generalized or localized scleroderma, although rare, was first reported in the literature by Addisson in 1884. These nodules usually appear during evolution. These scleroderma are then described as being keloidal or nodular. We report 3 cases of nodules on localized scleroderma which appeared at the beginning of the dermatosis and where the scleroderma had a similar unusual irregularly pigmented appearance.

  13. The trehalose utilization gene thuA ortholog in Mesorhizobium loti does not influence competitiveness for nodulation on Lotus spp.

    Science.gov (United States)

    Ampomah, Osei Yaw; Jensen, John Beck

    2014-03-01

    Competitiveness for nodulation is a desirable trait in rhizobia strains used as inoculant. In Sinorhizobium meliloti 1021 mutation in either of the trehalose utilization genes thuA or thuB influences its competitiveness for root colonization and nodule occupancy depending on the interacting host. We have therefore investigated whether mutation in the thuA ortholog in Mesorhizobium loti MAFF303099 also leads to a similar competitive phenotype on its hosts. The results show that M. loti thuA mutant Ml7023 was symbiotically effective and was as competitive as the wild type in colonization and nodule occupancy on Lotus corniculatus and Lotus japonicus. The thuA gene in M. loti was not induced during root colonization or in the infection threads unlike in S. meliloti, despite its induction by trehalose and high osmolarity in in vitro assays.

  14. Contribution à l’étude bioécologique de la faune des Invertébrés dans les trois stations à Santolina incana (Astéracées) dans le parc de Tlemcen

    OpenAIRE

    Djami, Yamina

    2016-01-01

    La région de Tlemcen est située dans le nord-ouest de l’Algérie. Elle se caractérise par le climat méditerranéen. Le Parc National de Tlemcen s’étend sur la partie nord des monts de Tlemcen. Santolina incana est une plante médicinale appartenant à la famille des Astéracées. Le but de cette étude est de faire un inventaire faunistique dans les stations à Santolina incana. Trois stations faisant partie du jardin du parc de Tlemcen sont décrites. Les échantillonnages sont effectué...

  15. Identifying abnormalities in symbiotic development between Trifolium spp. and Rhizobium leguminosarum bv. trifolii leading to sub-optimal and ineffective nodule phenotypes

    Science.gov (United States)

    Melino, V. J.; Drew, E. A.; Ballard, R. A.; Reeve, W. G.; Thomson, G.; White, R. G.; O'Hara, G. W.

    2012-01-01

    Background and Aims Legumes overcome nitrogen limitations by entering into a mutualistic symbiosis with N2-fixing bacteria (rhizobia). Fully compatible associations (effective) between Trifolium spp. and Rhizobium leguminosarum bv. trifolii result from successful recognition of symbiotic partners in the rhizosphere, root hair infection and the formation of nodules where N2-fixing bacteroids reside. Poorly compatible associations can result in root nodule formation with minimal (sub-optimal) or no (ineffective) N2-fixation. Despite the abundance and persistence of strains in agricultural soils which are poorly compatible with the commercially grown clover species, little is known of how and why they fail symbiotically. The aims of this research were to determine the morphological aberrations occurring in sub-optimal and ineffective clover nodules and to determine whether reduced bacteroid numbers or reduced N2-fixing activity is the main cause for the Sub-optimal phenotype. Methods Symbiotic effectiveness of four Trifolium hosts with each of four R. leguminosarum bv. trifolii strains was assessed by analysis of plant yields and nitrogen content; nodule yields, abundance, morphology and internal structure; and bacteroid cytology, quantity and activity. Key Results Effective nodules (Nodule Function 83–100 %) contained four developmental zones and N2-fixing bacteroids. In contrast, Sub-optimal nodules of the same age (Nodule Function 24–57 %) carried prematurely senescing bacteroids and a small bacteroid pool resulting in reduced shoot N. Ineffective-differentiated nodules carried bacteroids aborted at stage 2 or 3 in differentiation. In contrast, bacteroids were not observed in Ineffective-vegetative nodules despite the presence of bacteria within infection threads. Conclusions Three major responses to N2-fixation incompatibility between Trifolium spp. and R. l. trifolii strains were found: failed bacterial endocytosis from infection threads into plant cortical

  16. Genetic diversity of nodulating and non-nodulating rhizobia associated with wild soybean (Glycine soja Sieb. & Zucc.) in different ecoregions of China.

    Science.gov (United States)

    Wu, Li Juan; Wang, Hai Qing; Wang, En Tao; Chen, Wen Xin; Tian, Chang Fu

    2011-06-01

    A total of 99 bacterial isolates that originated from root nodules of Glycine soja were characterized with restriction analyses of amplified 16S ribosomal DNA and 16S-23S rDNA intergenic spacers (ITS), and sequence analyses of 16S rRNA, rpoB, atpD, recA and nodC genes. When tested for nodulation of G. soja, 72 of the isolates were effective symbionts, and these belonged to five species: Bradyrhizobium japonicum, Bradyrhizobium elkanii, Bradyrhizobium yuanmingense, Bradyrhizobium liaoningense and Sinorhizobium fredii. All of these, except some B. yuanmingense strains, also formed effective nodules on the domesticated soybean Glycine max. The remaining 27 isolates did not nodulate either host, but were identified as Rhizobium. Phylogeny nodC in the G. soja symbionts suggested that this symbiosis gene was mainly maintained by vertical gene transfer. Different nodC sublineages and rrs-ITS clusters reflected the geographic origins of isolates in this study. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  17. Limited Utility of Pulmonary Nodule Risk Calculators for Managing Large Nodules.

    Science.gov (United States)

    Hammer, Mark M; Nachiappan, Arun C; Barbosa, Eduardo J Mortani

    The optimal management of large pulmonary nodules, at higher risk for lung cancer, has not been determined, and it remains unclear as to which patients should undergo follow-up imaging vs invasive tissue diagnosis via biopsy or surgical resection. Through search of radiology reports, 86 nodules from our institution were identified using the inclusion criterion of solid nodules measuring greater than 8mm. We evaluated these nodules with a number of risk prediction calculators, including the Brock University model, and compared these against the proven diagnosis. Of 86 nodules, 59 (69%) nodules were malignant. The most accurate predictive model, the Brock University calculator, underestimated the risk for this group at 33%. At its optimal threshold, this model had a positive predictive value of 81% and negative predictive value of 53%. Notwithstanding the low negative predictive value, the positive predictive value was no better than patients clinically selected for biopsy (86% of biopsies were malignant). Existing nodule risk prediction calculators are of limited usage in guiding the management of large pulmonary nodules. At present, the accuracy of these models in this setting is inferior to expert clinical judgment, and future work is needed to develop management algorithms for higher-risk nodules. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Pulmonary nodules secondary to total parenteral alimentation

    International Nuclear Information System (INIS)

    Landry, B.A.; Melhem, R.E.

    1989-01-01

    A seven-year-old male, who had a retroperitoneal alveolar rhabdomyosarcoma and was on total parenteral alimentation (TPN) developed muliple pulmonary nodules, indistinguishable from metastases. These proved to be multiple lipid emboli on open biopsy. (orig.)

  19. Nodule bottom backscattering study using multibeam echosounder

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, B.; Raju, Y.S.N.; Nair, R.R.

    A study is carried out to observe the angular dependence of backscattering strength at nodule area where grab sample and photographic data is available. Theoretical study along with the experimentally observed data shows that the backscattering...

  20. Actinorhizal nitrogen fixing nodules: infection process, molecular ...

    African Journals Online (AJOL)

    Actinorhizal nitrogen fixing nodules: infection process, molecular biology and genomics. Mariana Obertello, Mame Oureye SY, Laurent Laplaze, Carole Santi, Sergio Svistoonoff, Florence Auguy, Didier Bogusz, Claudine Franche ...

  1. Pulmonary nodules secondary to total parenteral alimentation

    Energy Technology Data Exchange (ETDEWEB)

    Landry, B.A.; Melhem, R.E.

    1989-07-01

    A seven-year-old male, who had a retroperitoneal alveolar rhabdomyosarcoma and was on total parenteral alimentation (TPN) developed muliple pulmonary nodules, indistinguishable from metastases. These proved to be multiple lipid emboli on open biopsy. (orig.).

  2. Atypical Localized Rheumatoid Nodule: Case Report

    Directory of Open Access Journals (Sweden)

    KORHAN BARIS BAYRAM

    2015-01-01

    Full Text Available Rheumatoid nodules can be seen in about 30% of patiens with rheumatoid arthritis. They are occasionally localized subcutaneous, but they can rarely seen in visceral organs. Their appearance can be confused with many clinical conditions when they have atypical localizations. To exclude the presence of a malignancy, these lesions should always be investigated. We aimed to discuss a patient with rheumatoid nodule localized in close neighborhood of hyoid bone, presumed as malignancy.

  3. Lotus japonicus nodulation requires two GRAS-domain regulators, NSP1 and NSP2

    DEFF Research Database (Denmark)

    Heckmann, Anne Birgitte Lau; Lombardo, Fabien; Miwa, Hiroki

    A nodulation-defective mutant of Lotus japonicus does not initiate nodule cortical cell division in response to Mesorhizobium loti, but induces root hair deformation, Nod factor-induced calcium spiking, and mycorrhization. We have shown that this mutant has a premature stop in the NSP1 (Nodulation...... Signalling Pathway 1) gene (Ljnsp1-1) resulting in loss of the C-terminal 23 amino acids (aa) and we recently identified another mutant in NSP1 (Ljnsp1-2) with a truncated protein of 341 aa. Additionally, we have sequenced and isolated a mutant in LjNSP2 (Ljnsp2-3) that has a premature stop codon showing...

  4. Bradyrhizobium neotropicale sp. nov., isolated from effective nodules of Centrolobium paraense

    OpenAIRE

    Zilli, Jerri E; Baraúna, Alexandre C; da Silva, Krisle; De Meyer, Sofie; Farias, Eliane NC; Kaminski, Paulo E; da Costa, Ismaele B; Ardley, Julie K; Willems, Anne; Camacho, Natalia N; Dourado, Fernanda dos S; O'Hara, Graham

    2014-01-01

    Root nodule bacteria were isolated from Centrolobium paraense Tul. grown in soils from the Amazon region, State of Roraima (Brazil). 16S rRNA gene sequence analysis of seven strains (BR 10247(T), BR 10296, BR 10297, BR 10298, BR 10299, BR 10300 and BR 10301) placed them in the genus Bradyrhizobium with the closest neighbours being the type strains of Bradyrhizobium paxllaeri (98.8 % similarity), Bradyrhizobium icense (98.8 %), Bradyrhizobium lablabi (98.7 %), Bradyrhizobium jicamae (98.6 %), ...

  5. Pulmonary nodule classification with deep residual networks.

    Science.gov (United States)

    Nibali, Aiden; He, Zhen; Wollersheim, Dennis

    2017-10-01

    PURPOSE  : Lung cancer has the highest death rate among all cancers in the USA. In this work we focus on improving the ability of computer-aided diagnosis (CAD) systems to predict the malignancy of nodules from cropped CT images of lung nodules. We evaluate the effectiveness of very deep convolutional neural networks at the task of expert-level lung nodule malignancy classification. Using the state-of-the-art ResNet architecture as our basis, we explore the effect of curriculum learning, transfer learning, and varying network depth on the accuracy of malignancy classification. Due to a lack of public datasets with standardized problem definitions and train/test splits, studies in this area tend to not compare directly against other existing work. This makes it hard to know the relative improvement in the new solution. In contrast, we directly compare our system against two state-of-the-art deep learning systems for nodule classification on the LIDC/IDRI dataset using the same experimental setup and data set. The results show that our system achieves the highest performance in terms of all metrics measured including sensitivity, specificity, precision, AUROC, and accuracy. The proposed method of combining deep residual learning, curriculum learning, and transfer learning translates to high nodule classification accuracy. This reveals a promising new direction for effective pulmonary nodule CAD systems that mirrors the success of recent deep learning advances in other image-based application domains.

  6. Nodule-enhanced expression of a sucrose phosphate synthase gene member (MsSPSA) has a role in carbon and nitrogen metabolism in the nodules of alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Aleman, Lorenzo; Ortega, Jose Luis; Martinez-Grimes, Martha; Seger, Mark; Holguin, Francisco Omar; Uribe, Diana J; Garcia-Ibilcieta, David; Sengupta-Gopalan, Champa

    2010-01-01

    Sucrose phosphate synthase (SPS) catalyzes the first step in the synthesis of sucrose in photosynthetic tissues. We characterized the expression of three different isoforms of SPS belonging to two different SPS gene families in alfalfa (Medicago sativa L.), a previously identified SPS (MsSPSA) and two novel isoforms belonging to class B (MsSPSB and MsSPSB3). While MsSPSA showed nodule-enhanced expression, both MsSPSB genes exhibited leaf-enhanced expression. Alfalfa leaf and nodule SPS enzymes showed differences in chromatographic and electrophoretic migration and differences in V (max) and allosteric regulation. The root nodules in legume plants are a strong sink for photosynthates with its need for ATP, reducing power and carbon skeletons for dinitrogen fixation and ammonia assimilation. The expression of genes encoding SPS and other key enzymes in sucrose metabolism, sucrose phosphate phosphatase and sucrose synthase, was analyzed in the leaves and nodules of plants inoculated with Sinorhizobium meliloti. Based on the expression pattern of these genes, the properties of the SPS isoforms and the concentration of starch and soluble sugars in nodules induced by a wild type and a nitrogen fixation deficient strain, we propose that SPS has an important role in the control of carbon flux into different metabolic pathways in the symbiotic nodules.

  7. RbohB, a Phaseolus vulgaris NADPH oxidase gene, enhances symbiosome number, bacteroid size, and nitrogen fixation in nodules and impairs mycorrhizal colonization.

    Science.gov (United States)

    Arthikala, Manoj-Kumar; Sánchez-López, Rosana; Nava, Noreide; Santana, Olivia; Cárdenas, Luis; Quinto, Carmen

    2014-05-01

    The reactive oxygen species (ROS) generated by respiratory burst oxidative homologs (Rbohs) are involved in numerous plant cell signaling processes, and have critical roles in the symbiosis between legumes and nitrogen-fixing bacteria. Previously, down-regulation of RbohB in Phaseolus vulgaris was shown to suppress ROS production and abolish Rhizobium infection thread (IT) progression, but also to enhance arbuscular mycorrhizal fungal (AMF) colonization. Thus, Rbohs function both as positive and negative regulators. Here, we assessed the effect of enhancing ROS concentrations, by overexpressing PvRbohB, on the P. vulgaris--rhizobia and P. vulgaris--AMF symbioses. We estimated superoxide concentrations in hairy roots overexpressing PvRbohB, determined the status of early and late events of both Rhizobium and AMF interactions in symbiont-inoculated roots, and analyzed the nodule ultrastructure of transgenic plants overexpressing PvRbohB. Overexpression of PvRbohB significantly enhanced ROS production, the formation of ITs, nodule biomass, and nitrogen-fixing activity, and increased the density of symbiosomes in nodules, and the density and size of bacteroides in symbiosomes. Furthermore, PvCAT, early nodulin, PvSS1, and PvGOGAT transcript abundances were elevated in these nodules. By contrast, mycorrhizal colonization was reduced in roots that overexpressed RbohB. Overexpression of PvRbohB augmented nodule efficiency by enhancing nitrogen fixation and delaying nodule senescence, but impaired AMF colonization. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  8. "Nodule in Nodule" on Thyroid Ultrasonography: Possibility of Follicular Carcinoma Transformed from Benign Thyroid Tumor.

    Science.gov (United States)

    Kobayashi, Kaoru; Ota, Hisashi; Hirokawa, Mitsuyoshi; Yabuta, Tomonori; Fukushima, Mitsuhiro; Masuoka, Hiroo; Higashiyama, Takuya; Kihara, Minoru; Ito, Yasuhiro; Miya, Akihiro; Miyauchi, Akira

    2017-04-01

    It is generally considered impossible to differentiate follicular carcinomas from follicular adenomas by means of ultrasonography or cytology before surgery. Therefore, follicular carcinoma is histopathologically diagnosed by verifying capsular and/or vascular invasion after surgery. However, ultrasonography may play an important role in diagnosing follicular carcinoma preoperatively in a small number of cases. Four cases of follicular carcinoma or follicular neoplasm that transformed from a benign thyroid tumor and demonstrated a "nodule in nodule" appearance on ultrasonography are presented in this report. Characteristic ultrasound features of such patients are: (1) a "nodule in nodule" appearance, (2) a well-defined boundary line between the nodules, and (3) separate distribution of blood signals within each nodule. A small number of patients with follicular carcinomas or follicular neoplasms may present with a "nodule in nodule" appearance on ultrasonography. It was suggested a long time ago that follicular carcinomas may develop from benign thyroid tumors. The fact that follicular carcinomas appear within benign tumors may be evidence of thyroid tumorigenesis.

  9. Cromatografía de gases–espectrometría de masas de compuestos fitobioactivos del aceite esencial de Satureja incana

    Directory of Open Access Journals (Sweden)

    Joseph Ricaldi Sarapura

    2014-12-01

    Full Text Available Objetivos: Analizar la composición de fitobioactivos del aceite esencial de Satureja incana por cromatografía de gases acoplada a espectrometría de masas (GC-MS, por sus siglas en inglés; y determinar rendimiento extractivo y características físico-químicas del aceite esencial de Satureja incana. Métodos: Se colectó ramas tiernas en estado de floración, con cortes de 20-35 cm, ubicación de recolecta a una altitud 2 682 msnm; distrito de Palca, provincia Tarma, región Junín. Extracción: equipo extractor de acero inoxidable, tiempo 1 hora. Caracterización físico-química: Norma Técnica Peruana. Análisis GC-SM: gas helio flujo 20 ml.min-1, inyección de 0,2 μl de aceite esencial, configuración térmica en gradiente. Resultados: El rendimiento de extracción fue 0,49 base seca con densidad relativa 0,9816; índice de refracción 1,4879 e índice de acidez 1,9860; y la composición fitoquímica: predomina concentración sesquiterpenica 66,37 % y monoterpenos 30,07 %; siendo los compuestos mayoritarios: germacreno D 25,91 %, β cariofileno 22,10 %, α-ocimeno 12,62 %, 4(8-p-mentona 6,73 %, humuleno 3,95 %, cariofileno óxido 3,08 %, limoneno 2,44 %; y minoritarios: β-bourbeneno 1,95 %, β-ocimeno 1,78 %, espatulenol 1,66 %, β-linalol 1,64 %, dlisopulegol 1,66 %, α-cubebeno 1,51 %, δ-Cadineno 0,89 %, α-pineno 0,45 %, β-pineno 0,52 %. Conclusiones: La presencia de algunos compuestos químicos respalda su uso etnofitofarmacobotánico. Presenta potencial característica para utilizarlo en formulaciones para plaguicidas debido a la presencia de germacreno D en alta concentración.

  10. Isolation and Characterization of Alfalfa-Nodulating Rhizobia Present in Acidic Soils of Central Argentina and Uruguay

    Science.gov (United States)

    del Papa, María F.; Balagué, Laura J.; Sowinski, Susana Castro; Wegener, Caren; Segundo, Eduardo; Abarca, Francisco Martínez; Toro, Nicolás; Niehaus, Karsten; Pühler, Alfred; Aguilar, O. Mario; Martínez-Drets, Gloria; Lagares, Antonio

    1999-01-01

    We describe the isolation and characterization of alfalfa-nodulating rhizobia from acid soils of different locations in Central Argentina and Uruguay. A collection of 465 isolates was assembled, and the rhizobia were characterized for acid tolerance. Growth tests revealed the existence of 15 acid-tolerant (AT) isolates which were able to grow at pH 5.0 and formed nodules in alfalfa with a low rate of nitrogen fixation. Analysis of those isolates, including partial sequencing of the genes encoding 16S rRNA and genomic PCR-fingerprinting with MBOREP1 and BOXC1 primers, demonstrated that the new isolates share a genetic background closely related to that of the previously reported Rhizobium sp. Or191 recovered from an acid soil in Oregon (B. D. Eardly, J. P. Young, and R. K. Selander, Appl. Environ. Microbiol. 58:1809–1815, 1992). Growth curves, melanin production, temperature tolerance, and megaplasmid profiles of the AT isolates were all coincident with these characteristics in strain Or191. In addition to the ability of all of these strains to nodulate alfalfa (Medicago sativa) inefficiently, the AT isolates also nodulated the common bean and Leucaena leucocephala, showing an extended host range for nodulation of legumes. In alfalfa, the time course of nodule formation by the AT isolate LPU 83 showed a continued nodulation restricted to the emerging secondary roots, which was probably related to the low rate of nitrogen fixation by the largely ineffective nodules. Results demonstrate the complexity of the rhizobial populations present in the acidic soils represented by a main group of N2-fixing rhizobia and a second group of ineffective and less-predominant isolates related to the AT strain Or191. PMID:10103231

  11. Sonographic scoring of solid thyroid nodules: effects of nodule size and suspicious cervical lymph node

    Directory of Open Access Journals (Sweden)

    Ozlem Unsal

    Full Text Available Abstract Introduction Ultrasound is the most frequently used imaging method to evaluate thyroid nodules. Sonographic characteristics of thyroid nodules which are concerning for malignancy are important to define the need for fine needle aspiration biopsy or open surgery. Objective To evaluate malignancy risk of solid thyroid nodules through sonographic scoring. The effects of nodule size ≥2 cm and associated pathologic cervical lymph node in scoring were examined in addition to generally excepted suspicious features. Methods Medical data of 123 patients underwent thyroid surgery were reviewed, and 89 patients (58 females, 31 males were included in the study. The presence and absence of each suspicious sonographic feature of thyroid nodules were scored as 1 and 0, respectively. Total ultrasound score was obtained by adding the positive ultrasound findings. Differently from the literature, nodule size ≥2 cm and associated pathologic cervical node were added in scoring criteria. The diagnostic performance of nodule characteristics for malignancy and the effect of total US score to discriminate malignant and benign disease were calculated. Results A significant relationship was found between malignancy and hypoechogenity, border irregularity, intranodular vascularity, and microcalcification (p < 0.05. Pathologic cervical node was observed predominantly in association with malignant nodules. Positive predictive value of suspicious cervical node for malignancy was 67%, similar to microcalcification. Nodule size ≥2 cm was not distinctive for diagnosis of malignancy. The number of suspicious sonographic features obtained with receiver operating characteristic analysis to discriminate between malignant and benign disease was three. Conclusion Sonographic scoring of thyroid nodules is an effective method for predicting malignancy. The authors suggest including associated pathologic node in the scoring criteria. Further studies with larger cohorts

  12. HMG I-like proteins from leaf and nodule nuclei interact with different AT motifs in soybean nodulin promoters

    DEFF Research Database (Denmark)

    Jacobsen, K; Laursen, N B; Jensen, Erik Østergaard

    1990-01-01

    Three different nuclear factors recognizing short AT-rich DNA sequences were identified in different organs of soybean. One factor (NAT2) was found to be present in mature nodules, another factor (NAT1) was detected in roots and nodules, and a third one (LAT1) was only observed in leaves. All three...... factors recognized several DNA sequences in the promoter region of the soybean nodulin N23 gene. Footprinting, deletion, and point mutation analyses revealed different binding properties for all three factors and further showed that even single base pair substitutions had a dramatic effect on binding...

  13. Influence of pCO2 on carbon allocation in nodulated Medicago sativa L.

    Science.gov (United States)

    Pereyra, Gabriela; Hartmann, Henrik; Ziegler, Waldemar; Michalzik, Beate; Gonzalez-Meler, Miquel; Trumbore, Susan

    2016-04-01

    Atmospheric CO2 concentrations (pCO_2) have been related to changes in plant carbon (C) availability and photosynthetic capacity, yet there is no clear consensus as to the effect of pCO2 on the plant C balance and on nitrogen fixation in symbiotic systems. We investigated how different pCO2 (Pleistocene: 170 ppm, ambient: 400 ppm and projected future: 700 ppm) influence C allocation in nodulated Medicago sativa L. We labeled 17 week old plants with depleted 13C (-34.7±1.2‰) and traced the label over a 9-day period, to assess the redistribution of newly assimilated C across different sinks, including nodules. We analyzed N concentrations in plant tissues and found no significant differences in leaves and roots across treatments. However, growth and C fixation rates increased with pCO_2, and differences were greatest between 170 ppm and 700 ppm. Across pCO2 treatments we observed a 13C-enrichment in roots compared to leaves. We further observed the highest 13C depletion of non-structural carbohydrates (NSCs) and respired CO2 in tissues of plants grown at 700 ppm, especially in leaves and nodules. Our preliminary results suggest that sink organs like roots and nodules are fed with newly-assimilated NSCs from leaves to support respiration, and especially in 170 ppm plants represented a major respiratory loss of newly assimilated C (≈ 35{%} of the total plant respiration). Our results suggest that although plant metabolic processes like photosynthesis and respiration are affected by changes in pCO_2, nitrogen acquisition in such a symbiotic system is not.

  14. Effect of different growing media on the growth and flowering of stock (matthiola incana) under the agro-climatic condition of dera ismail khan

    International Nuclear Information System (INIS)

    Waseem, K.; Hameed, A.; Jilani, M.S.; Kiran, M.; Ghazanfarullah, R.; Javeria, S.; Jilani, T.A

    2013-01-01

    A pot experiment was conducted to investigate the effect of different growing media on the growth and development of stock (Matthiola incana). Seven different growing media including soil (100%), leaf mold (100%), coconut husk (100%), soil + leaf mold (50:50), soil + coconut husk (50:50), leaf mold + coconut husk (50:50) and soil + leaf mold + coconut husk (33:33:33) were used to check the growth of Stock plants in pots. Data was recorded for different parameters including days to flower initiation, days to flowering, plant height (cm), leaves per plant, branches per plant, flowering clusters per plant, flowers per cluster, flowers per plant and flower persistence life (days), during this course of study. The overall performance of Stock was better in media having leaf mold as it took least days to flower initiation (75.83), maximum plant height (21.43 cm), flowering clusters per plant (4.11), number of flowers per cluster (8.45 days), flowers per plant (34.66). For better growth and flowering of Stock plant, leaf mold can be used as growing media in pots. (author)

  15. Two basic-helix-loop-helix genes (MYC-146 and GL3) from Arabidopsis can activate anthocyanin biosynthesis in a white-flowered Matthiola incana mutant.

    Science.gov (United States)

    Ramsay, Nicola A; Walker, Amanda R; Mooney, Mark; Gray, John C

    2003-06-01

    Basic helix-loop-helix (bHLH) proteins, similar to mammalian Myc transcription factors, regulate the anthocyanin biosynthetic pathway in both monocots and dicots. Two Arabidopsis bHLH genes, GLABRA3 (GL3) and MYC-146, encode proteins that are similar throughout the predicted amino acid sequence to R and DELILA, which regulate anthocyanin production in maize and snapdragon, respectively. Northern blot analysis indicates that MYC-146 is most highly expressed in flower buds and flowers. Expression of a MYC-146 cDNA from the CaMV 35S promoter was unable to complement the anthocyanin deficiency in a ttg1 mutant of Arabidopsis and resulted in no obvious phenotypic change in Columbia plants. However, transient expression of GL3 and MYC-146 upon microprojectile bombardment of petals of a white-flowered mutant of Matthiola incana was able to complement anthocyanin deficiency. The lack of anthocyanin-deficient Arabidopsis mutants mapping to the locations of GL3 and MYC-146 suggests that the two bHLH proteins may be partially redundant and overlap in function.

  16. [Cytogenic chorionic nodule of the uterus].

    Science.gov (United States)

    Frappart, L; Lin, H C; Gauthier, A M; Griot, A; Palayer, C; Vernevaut, Y; Bremond, A; Rochet, Y; Lesbros, F

    1985-01-01

    The authors report five observations of endometrial stromal nodules. These nodules are composed of cells identical to those of the endometrial stroma. They constitute the benign form of endometrial stromal tumors. From the macroscopic point of view, they present as nodular formations, most often single, well defined, non-fasciculated, whitish or yellowish sometimes cystisized. From the microscopic point of view, these nodules contain areas of plexiform or glandular arrangement with, occasionally, pseudo-rosettes. Small collagenous zones can often be observed. E.S.N. should be distinguished on the one hand from endolymphatic stromal myosis, and on the other hand from sarcoma of the endometrial stroma. Histogenesis of the lesion is also discussed.

  17. Deep-ocean ferromanganese crusts and nodules

    Science.gov (United States)

    Hein, James R.; Koschinsky, Andrea

    2014-01-01

    Ferromanganese crusts and nodules may provide a future resource for a large variety of metals, including many that are essential for emerging high- and green-technology applications. A brief review of nodules and crusts provides a setting for a discussion on the latest (past 10 years) research related to the geochemistry of sequestration of metals from seawater. Special attention is given to cobalt, nickel, titanium, rare earth elements and yttrium, bismuth, platinum, tungsten, tantalum, hafnium, tellurium, molybdenum, niobium, zirconium, and lithium. Sequestration from seawater by sorption, surface oxidation, substitution, and precipitation of discrete phases is discussed. Mechanisms of metal enrichment reflect modes of formation of the crusts and nodules, such as hydrogenetic (from seawater), diagenetic (from porewaters), and mixed diagenetic–hydrogenetic processes.

  18. Seabed topography and distribution of manganese nodules in the Central Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Kodagali, V.N.

    The relationship between seabed topography and distribution of nodules, recovery of free fall grab samplers, nodule size and chemical composition of manganese nodules in the Central Indian Ocean have been studied. Nodule abundance was greater (4...

  19. Lung Nodule Detection via Deep Reinforcement Learning

    Directory of Open Access Journals (Sweden)

    Issa Ali

    2018-04-01

    Full Text Available Lung cancer is the most common cause of cancer-related death globally. As a preventive measure, the United States Preventive Services Task Force (USPSTF recommends annual screening of high risk individuals with low-dose computed tomography (CT. The resulting volume of CT scans from millions of people will pose a significant challenge for radiologists to interpret. To fill this gap, computer-aided detection (CAD algorithms may prove to be the most promising solution. A crucial first step in the analysis of lung cancer screening results using CAD is the detection of pulmonary nodules, which may represent early-stage lung cancer. The objective of this work is to develop and validate a reinforcement learning model based on deep artificial neural networks for early detection of lung nodules in thoracic CT images. Inspired by the AlphaGo system, our deep learning algorithm takes a raw CT image as input and views it as a collection of states, and output a classification of whether a nodule is present or not. The dataset used to train our model is the LIDC/IDRI database hosted by the lung nodule analysis (LUNA challenge. In total, there are 888 CT scans with annotations based on agreement from at least three out of four radiologists. As a result, there are 590 individuals having one or more nodules, and 298 having none. Our training results yielded an overall accuracy of 99.1% [sensitivity 99.2%, specificity 99.1%, positive predictive value (PPV 99.1%, negative predictive value (NPV 99.2%]. In our test, the results yielded an overall accuracy of 64.4% (sensitivity 58.9%, specificity 55.3%, PPV 54.2%, and NPV 60.0%. These early results show promise in solving the major issue of false positives in CT screening of lung nodules, and may help to save unnecessary follow-up tests and expenditures.

  20. Large philipsite crystal as ferromanganese nodule nucleus

    Digital Repository Service at National Institute of Oceanography (India)

    Ghosh, A.K.; Mukhopadhyay, R.

    absorption spectophotometry. Samples for AAS analysis were prepared using standard HF, HNO3, HC103, and HCI treatment and analyzed with 0.1 N HCI solution, along with a USGS A1 manganese nodule standard. The precision of the analyses was better than ~ 5~o... of ferroxyhydroxides in siliceous sediments (profle N3, Fig. 2), thus leaving free Mn to form todorokite-rich nodules (Nath and Rao 1988). Todorokite effectively incorporates Cu and Ni in their crystal struc- ture, and an increase in the concentration...

  1. Grade distributions in manganese nodules of Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Sudhakar, M.

    Data concerning to geological setting physical characteristics and bulk chemical composition of the nodules sampled from CIOB were stored in the Computer Data Bank of this Institute. Bulk chemical composition of nodules, in which grade is expressed...

  2. Solitary necrotic nodule of the liver: parasitic origin?

    OpenAIRE

    Tsui, W. M.; Yuen, R. W.; Chow, L. T.; Tse, C. C.

    1992-01-01

    AIMS: To report further cases of solitary necrotic nodule of the liver and to study its nature. METHODS: Seven nodules were retrieved from 4000 necropsy and surgical liver specimens coming to light over the past five years. All of them satisfied the diagnostic criteria of solitary necrotic nodule: a solid lesion with a central necrotic core and a hyalinised fibrotic capsule containing elastic fibres. Their clinicopathological features were reviewed. RESULTS: The nodules were incidental findin...

  3. Genome sequence of the clover-nodulating Rhizobium leguminosarum bv. trifolii strain SRDI565.

    Science.gov (United States)

    Reeve, Wayne; Drew, Elizabeth; Ballard, Ross; Melino, Vanessa; Tian, Rui; De Meyer, Sofie; Brau, Lambert; Ninawi, Mohamed; Teshima, Hazuki; Goodwin, Lynne; Chain, Patrick; Liolios, Konstantinos; Pati, Amrita; Mavromatis, Konstantinos; Ivanova, Natalia; Markowitz, Victor; Woyke, Tanja; Kyrpides, Nikos

    2013-01-01

    Rhizobium leguminosarum bv. trifolii SRDI565 (syn. N8-J) is an aerobic, motile, Gram-negative, non-spore-forming rod. SRDI565 was isolated from a nodule recovered from the roots of the annual clover Trifolium subterraneum subsp. subterraneum grown in the greenhouse and inoculated with soil collected from New South Wales, Australia. SRDI565 has a broad host range for nodulation within the clover genus, however N2-fixation is sub-optimal with some Trifolium species and ineffective with others. Here we describe the features of R. leguminosarum bv. trifolii strain SRDI565, together with genome sequence information and annotation. The 6,905,599 bp high-quality-draft genome is arranged into 7 scaffolds of 7 contigs, contains 6,750 protein-coding genes and 86 RNA-only encoding genes, and is one of 100 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project. PMID:24976879

  4. Short Communication Synergistic effect of rhizobia and plant growth promoting rhizobacteria on the growth and nodulation of lentil seedlings under axenic conditions

    Directory of Open Access Journals (Sweden)

    Muhammad Zafar-ul-Hye

    2013-05-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR containing ACC-deaminase in combination with rhizobia can improve the growth and nodulation in plants by suppressing the endogenous level of ethylene. In the present study, ten strains, each of PGPR and rhizobia from the previously screened cultures were tested for their effect as co-inoculants on growth and nodulation of lentil in growth pouches under axenic conditions. Results showed that most of the combinations improved the lentil growth as compared to the un-inoculated control. Maximum increase in shoot length (1.87 fold, root length (1.97 fold and total biomass (1.98 fold over the un-inoculated control was observed in the treatment where the lentil seedlings were inoculated with the combination Z24P10. Co-inoculation also improved the nodulation in lentil and the maximum number of nodules plant-1 (24 nodules were observed in the combination Z22P10. However, there was no nodulation in few combinations. It is concluded that the co-inoculation with rhizobia and PGPR containing ACC-deaminase has improved the growth and nodulation in lentil under axenic conditions and the selected combinations may be evaluated in pot and field trials

  5. DROUGHT-INDUCED EFFECTS AND RECOVERY OF NITRATE ASSIMILATION AND NODULE ACTIVITY IN COWPEA PLANTS INOCULATED WITH BRADYRHIZOBIUM SPP. UNDER MODERATE NITRATE LEVEL

    Directory of Open Access Journals (Sweden)

    Silveira Joaquim Albenísio Gomes da

    2001-01-01

    Full Text Available This study was carried out to establish comparative effects of drought and recovery on the nitrate assimilation and nodule activity related to N2 fixation in cowpea plants [Vigna unguiculata L. (Walp.] previously inoculated with Bradyrhizobium spp. BR-3256 (CB-756 strain in the presence of 5 mol m-3 NO-3. Twenty-eight-day-old nodulated plants were submitted to water deprivation during 4 consecutive days and afterwards resupplied with nutrient solution during 2 days. The water deprivation caused a rapid increase in the nitrate content in root and a marked reduction in leaf nitrate reductase (NR activity. In contrast nodule NR activity was slightly increased by water deprivation. Concomitantly, in nodules of water stressed plants, leghemoglobin and glutamine synthetase (GS activity declined and a progressive reduction in ureide-N concentration in xylem sap was observed. Leaf-NR activity increased rapidly after rehydration while leaf nitrate content declined. In contrast both GS activity and soluble protein content in the nodule continued to decline in rewatered plants. In addition the concentration of leghemoglobin recovered well, while the xylem ureide-N content experienced a slight increase after rehydration. Despite the nitrate assimilation in leaves and the nodule activity had been both severely affected by water stress, the rapid recovery of nitrate reductase activity suggests that the nitrate assimilation process is less sensitive to drought/rehydration cycle when cowpea plants are nodulated in presence of moderate nitrate level.

  6. Phosphatidylinositol 3-kinase function at very early symbiont perception: a local nodulation control under stress conditions?

    Science.gov (United States)

    Robert, Germán; Muñoz, Nacira; Alvarado-Affantranger, Xochitl; Saavedra, Laura; Davidenco, Vanina; Rodríguez-Kessler, Margarita; Estrada-Navarrete, Georgina; Sánchez, Federico; Lascano, Ramiro

    2018-04-09

    Root hair curling is an early and essential morphological change required for the success of the symbiotic interaction between legumes and rhizobia. At this stage rhizobia grow as an infection thread within root hairs and are internalized into the plant cells by endocytosis, where the PI3K enzyme plays important roles. Previous observations show that stress conditions affect early stages of the symbiotic interaction, from 2 to 30 min post-inoculation, which we term as very early host responses, and affect symbiosis establishment. Herein, we demonstrated the relevance of the very early host responses for the symbiotic interaction. PI3K and the NADPH oxidase complex are found to have key roles in the microsymbiont recognition response, modulating the apoplastic and intracellular/endosomal ROS induction in root hairs. Interestingly, compared with soybean mutant plants that do not perceive the symbiont, we demonstrated that the very early symbiont perception under sublethal saline stress conditions induced root hair death. Together, these results highlight not only the importance of the very early host-responses on later stages of the symbiont interaction, but also suggest that they act as a mechanism for local control of nodulation capacity, prior to the abortion of the infection thread, preventing the allocation of resources/energy for nodule formation under unfavorable environmental conditions.

  7. Buried nodules from the central Indian Ocean basin

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Parthiban, G.

    m. Maximum of 15 buried nodules were recovered in one core (AAS-22/ GC-07) and maximum depth where buried nodule recovered is at 5.35 m depth below seafloor. In the present study a total of twenty buried nodules from four sediment cores were utilized...

  8. Compact-Morphology-based poly-metallic Nodule Delineation.

    Science.gov (United States)

    Schoening, Timm; Jones, Daniel O B; Greinert, Jens

    2017-10-17

    Poly-metallic nodules are a marine resource considered for deep sea mining. Assessing nodule abundance is of interest for mining companies and to monitor potential environmental impact. Optical seafloor imaging allows quantifying poly-metallic nodule abundance at spatial scales from centimetres to square kilometres. Towed cameras and diving robots acquire high-resolution imagery that allow detecting individual nodules and measure their sizes. Spatial abundance statistics can be computed from these size measurements, providing e.g. seafloor coverage in percent and the nodule size distribution. Detecting nodules requires segmentation of nodule pixels from pixels showing sediment background. Semi-supervised pattern recognition has been proposed to automate this task. Existing nodule segmentation algorithms employ machine learning that trains a classifier to segment the nodules in a high-dimensional feature space. Here, a rapid nodule segmentation algorithm is presented. It omits computation-intense feature-based classification and employs image processing only. It exploits a nodule compactness heuristic to delineate individual nodules. Complex machine learning methods are avoided to keep the algorithm simple and fast. The algorithm has successfully been applied to different image datasets. These data sets were acquired by different cameras, camera platforms and in varying illumination conditions. Their successful analysis shows the broad applicability of the proposed method.

  9. Geochemistry of polymetallic nodules from the Central Indian Ocean basin

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A; Khadge, N.H.; Desa, J.A

    the thirteen different types of nodules present, only spherical and ellipsoidal nodules ranging in size from 2 cm to 2-4 cm with a rough, granular texture are abundant in the siliceous sediments. Different-sized nodules from the CIOB suggest formation...

  10. Root fractures

    DEFF Research Database (Denmark)

    Andreasen, Jens Ove; Christensen, Søren Steno Ahrensburg; Tsilingaridis, Georgios

    2012-01-01

    The purpose of this study was to analyze tooth loss after root fractures and to assess the influence of the type of healing and the location of the root fracture. Furthermore, the actual cause of tooth loss was analyzed.......The purpose of this study was to analyze tooth loss after root fractures and to assess the influence of the type of healing and the location of the root fracture. Furthermore, the actual cause of tooth loss was analyzed....

  11. Ectopic expression of miR156 represses nodulation and causes morphological and developmental changes in Lotus japonicus.

    Science.gov (United States)

    Wang, Ying; Wang, Zhishuo; Amyot, Lisa; Tian, Lining; Xu, Ziqin; Gruber, Margaret Y; Hannoufa, Abdelali

    2015-04-01

    The effects of microRNA156 overexpression on general plant architecture, branching, flowering time and nodulation were investigated in the model legume, Lotus japonicus. We cloned an miR156 homolog, LjmiR156a, from L. japonicus, and investigated its SQUAMOSA PROMOTER BINDING PROTEIN LIKE (SPL) genes and its biological function at enhancing vegetative biomass yield, extending flowering time, and its impact on nodulation. Thirteen potential targets for LjmiR156 were identified in vitro and their expression profiles were determined in aerial and underground parts of mature plants, including genes coding for eight SPLs, one WD-40, one RNA-directed DNA polymerase, two transport proteins, and one histidine-phosphotransfer protein. Two SPL and one WD-40 cleavage targets for LjmiR156-TC70253, AU089191, and TC57859-were identified. Transgenic plants with ectopic expression of LjmiR156a showed enhanced branching, dramatically delayed flowering, underdeveloped roots, and reduced nodulation. We also examined the transcript levels of key genes involved in nodule organogenesis and infection thread formation to determine the role of miR156 in regulating symbiosis. Overexpression of LjmiR156a led to repression of several nodulation genes during the early stages of root development such as three ENOD genes, SymPK, POLLUX, CYCLOPS, Cerberus, and Nsp1, and the stimulation of NFR1. Our results show that miR156 regulates vegetative biomass yield, flowering time and nodulation by silencing downstream target SPLs and other genes, suggesting that the miR156 regulatory network could be modified in forage legumes (such as alfalfa and trefoils) and in leafy vegetables (like lettuce and spinach) to positively impact economically valuable crop species.

  12. Host range, symbiotic effectiveness and nodulation competitiveness ...

    African Journals Online (AJOL)

    SERVER

    2008-04-17

    Apr 17, 2008 ... This symbiotic interaction is of agronomic and ecological importance because of its significant amount of nitrogen to the total nitrogen budget in terrestrial ecosystems (Postgate,. 1998). An important characteristic of this symbiotic interaction is host specificity, where defined species of rhizobia forms nodules ...

  13. Vocal fold nodules: morphological and immunohistochemical investigations.

    Science.gov (United States)

    Martins, Regina Helena Garcia; Defaveri, Julio; Custódio Domingues, Maria Aparecida; de Albuquerque E Silva, Rafael; Fabro, Alexandre

    2010-09-01

    The objective of this study was to investigate the morphological and immunohistochemical characteristics of vocal fold nodules. The study design was prospective and retrospective. For the histological study, we reviewed 15 slides from the surgical cases of vocal fold nodules, in which we analyzed epithelium, basal membrane (bm), and lamina propria. For the transmission and scanning electron microscopy (TEM, SEM) studies, five new cases on vocal fold nodules were included. Immunohistochemistry study was carried out in the 15 specimens, using antifibronectin, antilaminin, and anticollagen IV antibodies. The main histological alterations were epithelial hyperplasia (73.33%), basement membrane thickening (86.66%), edema, and fibrosis (93.33%). SEM--reduction in mucous lacing and increase in the desquamating cells, without epithelial erosion. TEM--hyperplasia of the epithelium, enlargement of the intercellular junctions, which was filled by fluid, subepithelial thickening of the lamina reticularis, and break points in the basal membrane. Immunohistochemistry--we identified greater immunoexpression of fibronectin on the basal membrane, on the lamina propria, and around the vessels. Antilaminin and anticollagen IV antibodies showed higher pigmentation on the endothelium of the vessels than that on the basal membrane. In vocal fold nodules, combined assessment using light microscopy, electron microscopy, and immunohistochemistry can reveal important morphological details useful in characterizing these lesions. 2010 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  14. Les nodules thyroidiens: Aspects epidemiologiques, cliniques et ...

    African Journals Online (AJOL)

    Thyroidectomy practised in all the patients has been dominated by a unilateral lobo-isthmectomia (55.96%). Immediate post-operative effect have been simples in 94.05% of cases and complicated in 5.95% of cases. Thyroid nodules are frequent in TOGO and affect in 90.46% of cases women. It is an ailment of the young ...

  15. The hyperfunctioning nodules of the thyroid

    International Nuclear Information System (INIS)

    Rosenthal, D.

    1975-01-01

    Iodine kinetic studies, using a double label ( 131 I - and T 4 -125 I), were performed on 8 patients with hot thyroid nodules, 3 diffuse toxic goiters and one normal control. This investigation was complemented by partial kinetic studies done on 62 other subjetcs, including normal controls and euthyroid or hyperthyroid patients with diffuse or nodular goiter [pt

  16. Histoplasmosis presenting with solitary pulmonary nodule: Two ...

    African Journals Online (AJOL)

    Pulmonary histoplasmosis is a granulomatous disease, whose diagnosis is not always easy, as it may simulate metastatic lesions due to similar radiographic findings. We herein report two cases of histoplasmosis with solitary pulmonary nodule in asymptomatic patients with histories of cancer surgeries, whose diagnoses ...

  17. Histoplasmosis presenting with solitary pulmonary nodule: Two ...

    African Journals Online (AJOL)

    2014-08-04

    Aug 4, 2014 ... hospital because of a right pulmonary nodule, discovered on a follow‑up chest radiogram. He had a history of abdominoperineal resection for rectal ... Given the patient's history of tumor resection, the ... Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China.

  18. A novel symbiovar (aegeanense) of the genus Ensifer nodulates Vigna unguiculata.

    Science.gov (United States)

    Tampakaki, Anastasia P; Fotiadis, Christos T; Ntatsi, Georgia; Savvas, Dimitrios

    2017-10-01

    Cowpea (Vigna unguiculata) forms nitrogen-fixing root nodules with diverse symbiotic bacteria, mainly slow-growing rhizobial species belonging to the genus Bradyrhizobium, although a few studies have reported the isolation of fast-growing rhizobia under laboratory and field conditions. Although much research has been done on cowpea-nodulating bacteria in various countries around the world, very limited information is available on cowpea rhizobia in European soils. The aim of this study was to study the genetic and phenotypic diversity of indigenous cowpea-nodulating rhizobia in Greece. The genetic diversity of indigenous rhizobia associated with cowpea was investigated through a polyphasic approach. ERIC-PCR based fingerprinting analysis grouped the isolates into three groups. Based on the analysis of the 16S rRNA genes, IGS and on the concatenation of six housekeeping genes (recA, glnII, gyrB, truA, thrA and SMc00019), rhizobial isolates were classified within the species Ensifer fredii. However, symbiotic gene phylogenies, based on nodC, nifH and rhcRST genes, showed that the Ensifer isolates are markedly diverged from type and reference strains of E. fredii and formed one clearly separate cluster. The E. fredii strains were able to nodulate and fix nitrogen in cowpea but not in soybean and common bean. The present study showed that cowpea is nodulated under field conditions by fast-growing rhizobia belonging to the species E. fredii. Based on the phylogenies, similarity levels of symbiotic genes and the host range, the Ensifer isolates may constitute a new symbiovar for which the name 'aegeanense' is proposed. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. US Diagnosis for Thyroid Nodules with an Indeterminate Cytology

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Jong Geun; Kim, Dong Wook [Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of); Kang, Tae Woo [Saegyaero Hospital, Busan (Korea, Republic of)

    2011-09-15

    We wanted to assess the diagnostic efficacy of thyroid ultrasound (US) for evaluating thyroid nodules with indeterminate cytology. Among 1865 nodules in 1278 patients who received a prospective US diagnosis of their thyroid nodule(s) and who subsequently underwent US-guided fine-needle aspiration, 130 nodules with indeterminate cytology were enrolled in the study. Each thyroid nodule was prospectively classified by a single radiologist into 1 of 5 diagnostic categories: 'benign', 'probably benign', 'indeterminate', 'suspicious for malignancy' and 'malignant.' The solid nodules were classified using all 5 categories and the partially cystic nodules classified using 4 categories ('indeterminate' was omitted). We calculated the diagnostic efficacy of thyroid US by comparing the US diagnoses with the pathology results. Of 130 nodules with indeterminate cytology (130/1865, 7.0%), 62 nodules were surgically removed. Nineteen nodules were assigned to the indeterminate category on US. The malignantly rate of the US-indeterminate category was 56.5% (35/62). The sensitivity, specificity and positive and negative predictive values were 81.0%, 81.8%, 81.0%, 81.8% and 81.4%, respectively, when US-indeterminate nodules were excluded. There was no significant difference of diagnostic efficacy when these nodules were reclassified as malignant, but there was a significant difference of diagnostic efficacy when these nodules were reclassified as benign. Our US classification may be a feasible method for managing thyroid nodules with indeterminate cytology

  20. Giant hepatic regenerative nodules in Alagille syndrome

    International Nuclear Information System (INIS)

    Rapp, Jordan B.; Bellah, Richard D.; Anupindi, Sudha A.; Maya, Carolina; Pawel, Bruce R.

    2017-01-01

    Children with Alagille syndrome undergo surveillance radiologic examinations as they are at risk for developing cirrhosis and hepatocellular carcinoma. There is limited literature on the imaging of liver masses in Alagille syndrome. We report the ultrasound (US) and magnetic resonance imaging (MRI) appearances of incidental benign giant hepatic regenerative nodules in this population. To describe the imaging findings of giant regenerative nodules in patients with Alagille syndrome. A retrospective search of the hospital database was performed to find all cases of hepatic masses in patients with Alagille syndrome during a 10-year period. Imaging, clinical charts, laboratory data and available pathology were reviewed and analyzed and summarized for each patient. Twenty of 45 patients with confirmed Alagille syndrome had imaging studies. Of those, we identified six with giant focal liver masses. All six patients had large central hepatic masses that were remarkably similar on US and MRI, in addition to having features of cirrhosis. In each case, the mass was located in hepatic segment VIII and imaging showed the mass splaying the main portal venous branches at the hepatic hilum, as well as smaller portal and hepatic venous branches coursing through them. On MRI, signal intensity of the mass was isointense to liver on T1-weighted sequences in four of six patients, but hyperintense on T1 in two of six patients. In all six cases, the mass was hypointense on T2- weighted sequences. The mass post-contrast was isointense to adjacent liver in all phases in five the cases. Five out of six patients had pathological correlation demonstrating preserved ductal architecture confirming the final diagnosis of a regenerative nodule. Giant hepatic regenerative nodules with characteristic US and MR features can occur in patients with Alagille syndrome with underlying cirrhosis. Recognizing these lesions as benign giant hepatic regenerative nodules should, thereby, mitigate any need for

  1. Giant hepatic regenerative nodules in Alagille syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, Jordan B. [Lewis Katz School of Medicine at Temple University, Department of Radiology, Temple University Hospital, Philadelphia, PA (United States); Bellah, Richard D.; Anupindi, Sudha A. [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA (United States); Maya, Carolina [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Pawel, Bruce R. [University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA (United States); The Children' s Hospital of Philadelphia, Department of Pathology and Laboratory Medicine, Philadelphia, PA (United States)

    2017-02-15

    Children with Alagille syndrome undergo surveillance radiologic examinations as they are at risk for developing cirrhosis and hepatocellular carcinoma. There is limited literature on the imaging of liver masses in Alagille syndrome. We report the ultrasound (US) and magnetic resonance imaging (MRI) appearances of incidental benign giant hepatic regenerative nodules in this population. To describe the imaging findings of giant regenerative nodules in patients with Alagille syndrome. A retrospective search of the hospital database was performed to find all cases of hepatic masses in patients with Alagille syndrome during a 10-year period. Imaging, clinical charts, laboratory data and available pathology were reviewed and analyzed and summarized for each patient. Twenty of 45 patients with confirmed Alagille syndrome had imaging studies. Of those, we identified six with giant focal liver masses. All six patients had large central hepatic masses that were remarkably similar on US and MRI, in addition to having features of cirrhosis. In each case, the mass was located in hepatic segment VIII and imaging showed the mass splaying the main portal venous branches at the hepatic hilum, as well as smaller portal and hepatic venous branches coursing through them. On MRI, signal intensity of the mass was isointense to liver on T1-weighted sequences in four of six patients, but hyperintense on T1 in two of six patients. In all six cases, the mass was hypointense on T2- weighted sequences. The mass post-contrast was isointense to adjacent liver in all phases in five the cases. Five out of six patients had pathological correlation demonstrating preserved ductal architecture confirming the final diagnosis of a regenerative nodule. Giant hepatic regenerative nodules with characteristic US and MR features can occur in patients with Alagille syndrome with underlying cirrhosis. Recognizing these lesions as benign giant hepatic regenerative nodules should, thereby, mitigate any need for

  2. OxyR-regulated catalase activity is critical for oxidative stress resistance, nodulation and nitrogen fixation in Azorhizobium caulinodans.

    Science.gov (United States)

    Zhao, Yue; Nickels, Logan M; Wang, Hui; Ling, Jun; Zhong, Zengtao; Zhu, Jun

    2016-07-01

    The legume-rhizobial interaction results in the formation of symbiotic nodules in which rhizobia fix nitrogen. During the process of symbiosis, reactive oxygen species (ROS) are generated. Thus, the response of rhizobia to ROS is important for successful nodulation and nitrogen fixation. In this study, we investigated how Azorhizobium caulinodans, a rhizobium that forms both root and stem nodules on its host plant, regulates ROS resistance. We found that in-frame deletions of a gene encoding the putative catalase-peroxidase katG or a gene encoding a LysR-family regulatory protein, oxyR, exhibited increased sensitivity to H2O2 We then showed that OxyR positively regulated katG expression in an H2O2-independent fashion. Furthermore, we found that deletion of katG or oxyR led to significant reduction in the number of stem nodules and decrease of nitrogen fixation capacities in symbiosis. Our results revealed that KatG and OxyR are not only critical for antioxidant defense in vitro, but also important for nodule formation and nitrogen fixation during interaction with plant hosts. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Root Hairs

    Science.gov (United States)

    Grierson, Claire; Nielsen, Erik; Ketelaarc, Tijs; Schiefelbein, John

    2014-01-01

    Roots hairs are cylindrical extensions of root epidermal cells that are important for acquisition of nutrients, microbe interactions, and plant anchorage. The molecular mechanisms involved in the specification, differentiation, and physiology of root hairs in Arabidopsis are reviewed here. Root hair specification in Arabidopsis is determined by position-dependent signaling and molecular feedback loops causing differential accumulation of a WD-bHLH-Myb transcriptional complex. The initiation of root hairs is dependent on the RHD6 bHLH gene family and auxin to define the site of outgrowth. Root hair elongation relies on polarized cell expansion at the growing tip, which involves multiple integrated processes including cell secretion, endomembrane trafficking, cytoskeletal organization, and cell wall modifications. The study of root hair biology in Arabidopsis has provided a model cell type for insights into many aspects of plant development and cell biology. PMID:24982600

  4. Uranium in Pacific deep-sea sediments and manganese nodules

    International Nuclear Information System (INIS)

    Kunzendorf, H.; Plueger, W.L.; Friedrich, G.H.

    1983-01-01

    A total of 1344 manganese nodules and 187 pelagic sediments from 9 areas in the North and the South Pacific were analyzed for U by the delayed-neutron counting technique. A strong positive correlation between U and Fe in nodules and sediments suggests a co-precipitative removal from sea water into the Fe-rich (ferromanganese mineral phase MnO 2 . Enrichment of U and Fe in nodules from the northwestern slopes of two submarine hills (U between 6 and 9 ppm) in the equatorial nodule belt is thought to be caused by directional bottom water flow creating elevated oxygenized conditions in areas opposed to the flow. Economically important nodule deposits from the nodule belt and the Peru Basin have generally low U contents, between 3 and 5 ppm. Insignificant resources of U of about 4 x 10 5 in the Pacific manganese nodules are estimated. (orig.)

  5. Infection of Lotus japonicus Roots by Mesorhizobium loti

    DEFF Research Database (Denmark)

    Markmann, Katharina; Radutoiu, Elena Simona; Stougaard, Jens

    2012-01-01

    Like the two important crop legumes soybean and common bean, the model legume Lotus japonicus develops determinate root nodules. L. japonicus is normally infected through root hair infection threads in a process closely synchronised with the progressing primordial cell divisions and organ...

  6. A Proteomic Approach of Bradyrhizobium/Aeschynomene Root and Stem Symbioses Reveals the Importance of the fixA Locus for Symbiosis

    Directory of Open Access Journals (Sweden)

    Nathanael Delmotte

    2014-02-01

    Full Text Available Rhizobia are soil bacteria that are able to form symbiosis with plant hosts of the legume family. These associations result in the formation of organs, called nodules in which bacteria fix atmospheric nitrogen to the benefit of the plant. Most of our knowledge on the metabolism and the physiology of the bacteria during symbiosis derives from studying roots nodules of terrestrial plants. Here we used a proteomics approach to investigate the bacterial physiology of photosynthetic Bradyrhizobium sp. ORS278 during the symbiotic process with the semi aquatical plant Aeschynomene indica that forms root and stem nodules. We analyzed the proteomes of bacteria extracted from each type of nodule. First, we analyzed the bacteroid proteome at two different time points and found only minor variation between the bacterial proteomes of 2-week- and 3-week-old nodules. High conservation of the bacteroid proteome was also found when comparing stem nodules and root nodules. Among the stem nodule specific proteins were those related to the phototrophic ability of Bradyrhizobium sp. ORS278. Furthermore, we compared our data with those obtained during an extensive genetic screen previously published. The symbiotic role of four candidate genes which corresponding proteins were found massively produced in the nodules but not identified during this screening was examined. Mutant analysis suggested that in addition to the EtfAB system, the fixA locus is required for symbiotic efficiency.

  7. Dual energy computed tomography of lung nodules: Differentiation of iodine and calcium in artificial pulmonary nodules in vitro

    International Nuclear Information System (INIS)

    Knöß, Naomi; Hoffmann, Beata; Krauss, Bernhard; Heller, Martin; Biederer, Jürgen

    2011-01-01

    Background: Iodine enhancement is a marker for malignancy in pulmonary nodules. The purpose of this in vitro study was to assess whether dual energy computed tomography (DECT) can be used to detect iodine and to distinguish iodine from disperse calcifications in artificial pulmonary nodules. Materials and methods: Small, medium, and large artificial nodules (n = 54), with increasing concentrations of iodine or calcium corresponding to an increase in Hounsfield Units (HU) of 15, 30, 45, and 90 at 120 kV, were scanned in a chest phantom with DECT at 80 and 140 kV. Attenuation values of each nodule were measured using semi-automated volumetric analysis. The mean DE ratio with 95% confidence intervals (CI) was calculated for each nodule. Results: The mean maximum diameter of the 18 small nodules was 12 mm (standard deviation: 0.4), 16 mm (0.4) for the 18 medium nodules, and 30 mm (1.1) for the 18 large nodules. There was no overlap of 95% CI of DE ratios of iodine and calcium in nodules ≥16 mm. In nodules <16 mm, there was an overlap of DE ratios in low contrast lesions. Conclusion: DECT can distinguish iodine from calcium in artificial nodules ≥16 mm in vitro. In smaller lesions, a clear differentiation is not possible.

  8. New development of MR imaging lung nodule simulator for detecting peripheral pulmonary nodules: Experimental and clinical studies

    International Nuclear Information System (INIS)

    Kono, M.; Yamasaki, K.; Adachi, S.; Kameda, K.; Tanaka, K.

    1987-01-01

    There are no appropriate phantoms for MR imaging because the parameters (rho, T1, T2) are not equivalent to those in human tissues. To evaluate the detectability of peripheral lung nodules with MR imaging, the authors devised lung nodule phantoms made of polyvinyl alcohol for evaluating spatial and contrast resolution. To evaluate the environmental effect around the phantoms, a thoracic phantom was made of polyvinyl alcohol, solid oils and artificial bone. Based on experimental results, T1, T2 values of the lung nodule phantom varied as a function of position. To determine tissue characterization of peripheral lung nodules with MR imaging, lung nodule phantoms with T1 and T2 values similar to those of lung cancer were compared with actual T1 and T2 values of lung nodules. It was strongly suggested that these phantoms would be useful for differentiation of malignant nodules from inflammatory lesion

  9. A 200 bp region of the pea ENOD12 promoter is sufficient for nodule-specific and nod factor induced expression

    DEFF Research Database (Denmark)

    Vijn, I; Christiansen, H; Lauridsen, P

    1995-01-01

    previously described. The isolation and characterization of a PsENOD12A genomic clone is presented in this paper. By using a Vicia hirsuta-Agrobacterium rhizogenes transformation system it is shown that both genes have a similar expression pattern in transgenic V. hirsuta root nodules. Promoter analyses...

  10. Soybean SAT1 (Symbiotic Ammonium Transporter 1) encodes a bHLH transcription factor involved in nodule growth and NH4+ transport

    NARCIS (Netherlands)

    Chiasson, D.M.; Loughlin, P.C.; Mazurkiewicz, D.; Mohammadidehcheshmeh, M.; Fedorova, E.E.; Okamoto, M.; McLean, E.; Glass, A.D.M.; Smith, S.E.; Bisseling, T.; Tyerman, S.D.; Day, D.A.; Kaiser, B.N.

    2014-01-01

    Glycine max symbiotic ammonium transporter 1 was first documented as a putative ammonium (NH4+) channel localized to the symbiosome membrane of soybean root nodules. We show that Glycine max symbiotic ammonium transporter 1 is actually a membrane-localized basic helix–loop–helix (bHLH) DNA-binding

  11. [Regulatory genes of garden pea (Pisum sativum L.) controlling the development of nitrogen-fixing nodules and arbuscular mycorrhiza: a review of basic and applied aspects

    DEFF Research Database (Denmark)

    Borisov, A Iu; Vasil'chikov, A G; Voroshilova, V A

    2007-01-01

    . Progress in identifying and cloning symbiotic genes is adequately reflected. The feasibility of using double inoculation as a means of increasing the plant productivity is demonstrated, in which the potential of a tripartite symbiotic system (pea plants-root nodule bacteria-arbuscular mycorrhiza...

  12. Pulmonary nodule registration in serial CT scans based on rib anatomy and nodule template matching

    International Nuclear Information System (INIS)

    Shi Jiazheng; Sahiner, Berkman; Chan, H.-P.; Hadjiiski, Lubomir; Zhou, C.; Cascade, Philip N.; Bogot, Naama; Kazerooni, Ella A.; Wu, Y.-T.; Wei, J.

    2007-01-01

    An automated method is being developed in order to identify corresponding nodules in serial thoracic CT scans for interval change analysis. The method uses the rib centerlines as the reference for initial nodule registration. A spatially adaptive rib segmentation method first locates the regions where the ribs join the spine, which define the starting locations for rib tracking. Each rib is tracked and locally segmented by expectation-maximization. The ribs are automatically labeled, and the centerlines are estimated using skeletonization. For a given nodule in the source scan, the closest three ribs are identified. A three-dimensional (3D) rigid affine transformation guided by simplex optimization aligns the centerlines of each of the three rib pairs in the source and target CT volumes. Automatically defined control points along the centerlines of the three ribs in the source scan and the registered ribs in the target scan are used to guide an initial registration using a second 3D rigid affine transformation. A search volume of interest (VOI) is then located in the target scan. Nodule candidate locations within the search VOI are identified as regions with high Hessian responses. The initial registration is refined by searching for the maximum cross-correlation between the nodule template from the source scan and the candidate locations. The method was evaluated on 48 CT scans from 20 patients. Experienced radiologists identified 101 pairs of corresponding nodules. Three metrics were used for performance evaluation. The first metric was the Euclidean distance between the nodule centers identified by the radiologist and the computer registration, the second metric was a volume overlap measure between the nodule VOIs identified by the radiologist and the computer registration, and the third metric was the hit rate, which measures the fraction of nodules whose centroid computed by the computer registration in the target scan falls within the VOI identified by the

  13. Interstitial laser photocoagulation for benign thyroid nodules: time to treat large nodules.

    Science.gov (United States)

    Amabile, Gerardo; Rotondi, Mario; Pirali, Barbara; Dionisio, Rosa; Agozzino, Lucio; Lanza, Michele; Buonanno, Luciano; Di Filippo, Bruno; Fonte, Rodolfo; Chiovato, Luca

    2011-09-01

    Interstitial laser photocoagulation (ILP) is a new therapeutic option for the ablation of non-functioning and hyper-functioning benign thyroid nodules. Amelioration of the ablation procedure currently allows treating large nodules. Aim of this study was to evaluate the therapeutic efficacy of ILP, performed according to a modified protocol of ablation, in patients with large functioning and non-functioning thyroid nodules and to identify the best parameters for predicting successful outcome in hyperthyroid patients. Fifty-one patients with non-functioning thyroid nodules (group 1) and 26 patients with hyperfunctioning thyroid nodules (group 2) were enrolled. All patients had a nodular volume ≥40 ml. Patients were addressed to 1-3 cycles of ILP. A cycle consisted of three ILP sessions, each lasting 5-10 minutes repeated at an interval of 1 month. After each cycle of ILP patients underwent thyroid evaluation. A nodule volume reduction, expressed as percentage of the basal volume, significantly occurred in both groups (F = 190.4; P < 0.0001 for group 1 and F = 100.2; P < 0.0001 for group 2). Receiver-operator-characteristic (ROC) curves were constructed for: (i) percentage of volume reduction; (ii) difference in nodule volume; (iii) total amount of energy delivered expressed in Joule. ROC curves identified the percentage of volume reduction as the best parameter predicting a normalized serum TSH (area under the curve 0.962; P < 0.0001). Intraoperative complications consisted in: (i) mild pain occurring in five (6.5%) patients, (ii) vasovagal reaction in two (2.6%) patients, (iii) fever within 24 hours from ILP in five (6.5%) patients. No major complications including persistent pain, laringeal nerve dysfunction, hypoparathyroidism, pseudocystic transformation, and/or neck fascitis were observed. ILP represents a valid alternative to surgery also for large benign thyroid nodules, both in terms of nodule size reduction and cure of

  14. Soybean nodulation and symbiotic nitrogen fixation in response to soil compaction and mulching

    Science.gov (United States)

    Siczek, A.; Lipiec, J.

    2009-04-01

    compared: low, medium and heavy (0, 3 or 5 passes, respectively). This resulted in a wide range of soil bulk density (1.2 to 1.65 Mg m-3) that can occur in the arable fields. To obtain uniform conditions for seed germination and initial seedling growth the entire plot area was tilled with a cultivator-harrow to a depth of 5 cm after soil compaction. Soybean "Aldana" seeds inoculated with B. japonicum were sown in rows with spacing of 0.3 m. After sowing half of each micro-plot was mulched with wheat straw (0.5 kg m-2) and another one - not. Nodulation was evaluated by using the parameters of nodule number and nodule weight and acetylene reduction assay was used for the measurement of nitrogenase activity. Number of nodules on root system under mulched and not mulched soil was the highest in not compacted and medium compacted soil, respectively and the lowest - in most compacted soil with mulch. Nitrogenase activity ( mol C2H4 h-1 plant-1) decreased as soil compaction increased but the more pronounced tendency and higher values were obtained in mulched plots. The results indicate that mulching in some range of soil compaction can improve soybean nodulation and nitrogen fixation. This work was funded in part by the Polish Ministry of Science and Higher Education (Grant No N N310 149635).

  15. Nitrogen use efficiency and life cycle of nodules in alfalfa after different mineral fertilization and soil cultivation

    Directory of Open Access Journals (Sweden)

    V. Vasileva

    2015-09-01

    Full Text Available Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertilization and soil cultivation practices were studied. Field trial was conducted in the Institute of Forage Crops, Pleven, Bulgaria on leached chernozem subsoil type and no irrigation. The next treatments were tested: i for fertilization as follows: N0P0K0 (control; N60P100K80 (an accepted technology; N23P100K35 (nitrogen was applied 1/2 in first year of growing and 1/2 in third year; N23P100K35 (nitrogen was supplied pre-sowing; N35P80K50, and Аmophose - 250 kg/ha, calculated at fertilizing rates N27P120K0; ii for soil cultivation as follows: soil loosing 10-12 cm, plough at depth 12-15 cm, 22-24 cm (an accepted technology, 18-22 cm and 30-35 cm. It was found that soil cultivation and mineral fertilization had effect on nitrogen use efficiency and life cycle of root nodules in Alfalfa. Nitrogen use efficiency was found to be highest at N23P100K35 and plough at the depth of 22-24 cm. Life cycle of root nodules was the longest at N35P80K50 and plough at the depth of 18-22 cm. The better root mass to nodule number ratio was found at N23P100K35 and plough at the depth of 22-24 cm.

  16. Segmentation of nodules on chest computed tomography for growth assessment

    International Nuclear Information System (INIS)

    Mullally, William; Betke, Margrit; Wang Jingbin; Ko, Jane P.

    2004-01-01

    Several segmentation methods to evaluate growth of small isolated pulmonary nodules on chest computed tomography (CT) are presented. The segmentation methods are based on adaptively thresholding attenuation levels and use measures of nodule shape. The segmentation methods were first tested on a realistic chest phantom to evaluate their performance with respect to specific nodule characteristics. The segmentation methods were also tested on sequential CT scans of patients. The methods' estimation of nodule growth were compared to the volume change calculated by a chest radiologist. The best method segmented nodules on average 43% smaller or larger than the actual nodule when errors were computed across all nodule variations on the phantom. Some methods achieved smaller errors when examined with respect to certain nodule properties. In particular, on the phantom individual methods segmented solid nodules to within 23% of their actual size and nodules with 60.7 mm3 volumes to within 14%. On the clinical data, none of the methods examined showed a statistically significant difference in growth estimation from the radiologist

  17. Altered susceptibility to infection by Sinorhizobium meliloti and Nectria haematococca in alfalfa roots with altered cell cycle.

    Science.gov (United States)

    Woo, H-H; Hirsch, A M; Hawes, M C

    2004-07-01

    Most infections of plant roots are initiated in the region of elongation; the mechanism for this tissue-specific localization pattern is unknown. In alfalfa expressing PsUGT1 antisense mRNA under the control of the cauliflower mosaic virus (CaMV) 35S promoter, the cell cycle in roots is completed in 48 h instead of 24 h, and border cell number is decreased by more than 99%. These plants were found to exhibit increased root-tip infection by a fungal pathogen and reduced nodule formation by a bacterial symbiont. Thus, the frequency of infection in the region of elongation by Nectria haematocca was unaffected, but infection of the root tip was increased by more than 90%; early stages of Sinorhizobium meliloti infection and nodule morphology were normal, but the frequency of nodulation was fourfold lower than in wild-type roots.

  18. Pemphigus Vulgaris with Solitary Toxic Thyroid Nodule

    Directory of Open Access Journals (Sweden)

    Mostafa Alfishawy

    2014-01-01

    Full Text Available Background. Pemphigus vulgaris is an autoimmune vesiculobullous disease, affecting the skin and mucous membranes. It is reported to be associated with other autoimmune diseases including autoimmune thyroid diseases. However we report herein a case of pemphigus vulgaris associated with autonomous toxic nodule. Case Presentation. A 51-year-old woman was evaluated for blisters and erosions that develop on her trunk, face, and extremities, with a five-year history of progressively enlarging neck mass, and a past medical history of pemphigus vulgaris seven years ago. The condition was associated with palpitation, dyspnea, and heat intolerance. Thyroid function tests and thyroid scan were compatible with the diagnosis of thyrotoxicosis due to autonomous toxic nodule. Exacerbation of pemphigus vulgaris was proved by skin biopsy from the patient which revealed histologic picture of pemphigus vulgaris. Conclusion. Autoimmune thyroid diseases are reported to associate pemphigus vulgaris. To our knowledge, this case is the first in the English literature to report association between pemphigus vulgaris and autonomous toxic nodule and highlights the possibility of occurrence of pemphigus vulgaris with a nonautoimmune thyroid disease raising the question: is it just a coincidence or is there an explanation for the occurrence of both conditions together?

  19. Nitrogen assimilation in soybean nodules, 2

    International Nuclear Information System (INIS)

    Ohyama, Takuji; Kumazawa, Kikuo

    1980-01-01

    15 N assimilation was studied in bacteroid and cytosol fractions of soybean nodules. In the first experiment, after exposing the intact nodules to 15 N 2 for 5 min and 10 min, most of the fixed 15 N was detected in cytosol fraction. In cytosol fraction, 15 N content of glutamine was the highest and followed by glutamic acid, alanine, and allantoin in this sequence, whereas, in bacteroid fraction, glutamic acid showed the highest 15 N content and alanine and glutamine followed. In the second experiment, 15 N assimilation of various 15 N-labeled compounds in the separated bacteroid and cytosol fractions was investigated. In the separated bacteroid fraction which was fed with 15 NH 4 , 15 N was incorporated very rapidly into glutamic acid, alanine, and aspartic acid, but very slowly into glutamine. From these results, it was suggested that most of the fixed ammonia was exported to cytosol and assimilated via glutamine synthetase to glutamine, then via glutamate synthase to glutamic acid, and from these compounds various nitrogenous compounds were formed, but in bacteroids glutamate dehydrogenase and alanine dehydrogenase played an important role in the assimilation of fixed ammonia though quantitatively the contribution to ammonia assimilation in nodules was much less compared with cytosol. (author)

  20. Co-existence of Rhizobia and Diverse Non-rhizobial Bacteria in the Rhizosphere and Nodules of Dalbergia odorifera Seedlings Inoculated with Bradyrhizobium elkanii, Rhizobium multihospitium–Like and Burkholderia pyrrocinia–Like Strains

    Directory of Open Access Journals (Sweden)

    Junkun Lu

    2017-11-01

    Full Text Available Rhizobia induce root nodules and fix atmospheric N2 for most legume species in exchange for carbon. However, the diverse endophytic non-rhizobial bacteria in legume nodules that co-exist with rhizobia are often ignored because they are difficult to cultivate using routine cultivation approaches. To enhance our understanding of the incidence and diversity of legume–bacteria associations, a high-throughput sequencing analysis of bacterial 16S rRNA genes was used to examine the bacterial community in the rhizospheres and root nodules of Dalbergia odorifera seedlings that were uninoculated or inoculated with Bradyrhizobium elkanii H255, Rhizobium multihospitium–like HT221, or Burkholderia pyrrocinia–like H022238, in two growth media (nitrogen [N]-supplied soil or N-omitted potting mix. Seedlings inoculated with Bradyrhizobium had significantly more nodules than seedlings in the other inoculation conditions, regardless of growth media. Using the 15N natural abundance method, it was shown that the inoculated plants had significantly higher N2 fixation efficiency (48–57% and specific nodule activity [269–313 μg N mg−1 of dry weight (dwt nodule] compared to the uninoculated plants (203 μg N mg−1 dwt nodule. The 16S rRNA gene analysis showed that there was generally a higher bacterial diversity in the rhizosphere than in the nodules in the corresponding condition. Both rhizobial inoculation and media status significantly altered the bacterial communities in the rhizospheres and nodules (P < 0.05, with the exception of the inoculated soil rhizospheres. Regarding non-rhizobial bacteria, three genera, i.e., Lactococcus, Bacillus, and Pseudomonas, were consistently enriched in the rhizosphere and Bradyrhizobium, Chloroplast norank (which belongs to Cyanobacteria, and Lactococcus were commonly found in the nodules. In contrast, common rhizobial genera (including Rhizobium, Mesorhizobium, and Burkholderia were only present in the nodules at low

  1. Defects in rhizobial cyclic glucan and lipopolysaccharide synthesis alter legume gene expression during nodule development

    DEFF Research Database (Denmark)

    D'Antuono, Alejandra L; Ott, Thomas; Krusell, Lene

    2008-01-01

    higher expression of phenylalanine ammonia lyase than wild-type nodules. Differences in expression pattern of genes involved in early recognition and signaling were observed in plants inoculated with the M. loti mutant strain affected in the synthesis of cyclic glucan. Udgivelsesdato: 2008-Jan......cDNA array technology was used to compare transcriptome profiles of Lotus japonicus roots inoculated with a Mesorhizobium loti wild-type and two mutant strains affected in cyclic beta(1-2) glucan synthesis (cgs) and in lipopolysaccharide synthesis (lpsbeta2). Expression of genes associated...

  2. Root patterning

    NARCIS (Netherlands)

    Scheres, Ben; Laskowski, Marta

    2016-01-01

    The mechanisms that pattern lateral root primordial are essential for the elaboration of root system architecture, a trait of key importance for future crop breeding. But which are most important: periodic or local cues? In this issue of Journal of Experimental Botany (pages 1411-1420), Kircher

  3. CT SCAN EVALUATION OF PULMONARY NODULE

    Directory of Open Access Journals (Sweden)

    A. Ravi Kumar

    2016-06-01

    Full Text Available BACKGROUND Lung carcinomas are quite commonly diagnosed. Thanks to the ever increasing smokers’ population. Majority of the city dwellers are at a higher risk of having this disease when compared to the village counterparts. The stigma through which the person and the family have to undergo before confirming the diagnosis is enormous. So the radiographic methods of diagnosing the malignancies have to improve. Before confirming the diagnosis, the radiologists, the treating physicians should be somewhat confident about the diagnosis so as to prepare the patients and their relatives for the most probable diagnosis before the confirmatory report. The confirmatory procedures include the PET scan and the Histopathology. Both are time consuming procedures and in an economy like ours, finding a PET scanning centre is rather difficult. So the most probable diagnosis has to be thought of using minimal resource. This study puts in a sincere effort to understand and evaluate the pulmonary nodule when identified by a CT scan. This paper is intended to help the practicing radiologists and also make life easy for a practicing physician to identify correctly the lesions and also help the patients to prevent further progression of the disease. METHODS The study was a cross-sectional study. The sample size of the study consisted of thirty patients. CT scan was done in thirty patients who were identified to have lung nodules either by other mode of radiological studies or first time identified in a CT scan itself. The study was conducted in Fathima Institute of Medical Sciences, Kadapa. The study was conducted from 2014 to 2015. RESULT Non-solid nodules were more in number when compared to the solid nodules. All the non-solid nodules were confirmed to be adenomas. Eighty percent of the nodules which were more than 8 mm in size were confirmed to be malignant. One hundred percent of the spiculated border on CT was confirmed to be malignant. In the present study

  4. Fixating on metals: new insights into the role of metals in nodulation and symbiotic nitrogen fixation.

    Science.gov (United States)

    González-Guerrero, Manuel; Matthiadis, Anna; Sáez, Ángela; Long, Terri A

    2014-01-01

    Symbiotic nitrogen fixation is one of the most promising and immediate alternatives to the overuse of polluting nitrogen fertilizers for improving plant nutrition. At the core of this process are a number of metalloproteins that catalyze and provide energy for the conversion of atmospheric nitrogen to ammonia, eliminate free radicals produced by this process, and create the microaerobic conditions required by these reactions. In legumes, metal cofactors are provided to endosymbiotic rhizobia within root nodule cortical cells. However, low metal bioavailability is prevalent in most soils types, resulting in widespread plant metal deficiency and decreased nitrogen fixation capabilities. As a result, renewed efforts have been undertaken to identify the mechanisms governing metal delivery from soil to the rhizobia, and to determine how metals are used in the nodule and how they are recycled once the nodule is no longer functional. This effort is being aided by improved legume molecular biology tools (genome projects, mutant collections, and transformation methods), in addition to state-of-the-art metal visualization systems.

  5. A thyroid nodule classification method based on TI-RADS

    Science.gov (United States)

    Wang, Hao; Yang, Yang; Peng, Bo; Chen, Qin

    2017-07-01

    Thyroid Imaging Reporting and Data System(TI-RADS) is a valuable tool for differentiating the benign and the malignant thyroid nodules. In clinic, doctors can determine the extent of being benign or malignant in terms of different classes by using TI-RADS. Classification represents the degree of malignancy of thyroid nodules. TI-RADS as a classification standard can be used to guide the ultrasonic doctor to examine thyroid nodules more accurately and reliably. In this paper, we aim to classify the thyroid nodules with the help of TI-RADS. To this end, four ultrasound signs, i.e., cystic and solid, echo pattern, boundary feature and calcification of thyroid nodules are extracted and converted into feature vectors. Then semi-supervised fuzzy C-means ensemble (SS-FCME) model is applied to obtain the classification results. The experimental results demonstrate that the proposed method can help doctors diagnose the thyroid nodules effectively.

  6. Small Nodules Localization on CT Images of Lungs

    Science.gov (United States)

    Snezhko, E. V.; Kharuzhyk, S. A.; Tuzikov, A. V.; Kovalev, V. A.

    2017-05-01

    According to the World Health Organization (WHO) lung cancer remains the leading cause of death of men among all malignant tumors [1, 2]. One of the reasons of such a statistics is the fact that the lung cancer is hardly diagnosed on the yearly stages when it is almost asymptomatic. The purpose of this paper is to present a Computer-Aided Diagnosis (CAD) software developed for assistance of early detection of nodules in CT lung images including solitary pulmonary nodules (SPN) as well as multiple nodules. The efficiency of nodule localization was intended to be as high as the level of the best practice. The software developed supports several functions including lungs segmentation, selection of nodule candidates and nodule candidates filtering.

  7. The Relation between Occupational Exposure and Thyroid Nodules, Isfahan 2008

    OpenAIRE

    Afshin Rezazadeh; Atoosa Adibi

    2010-01-01

    Background/Objective: Considering that thyroid nodules and thyroid cancer occur more frequently in people exposed chronically to radiation, the aim of this study was to evaluate the prevalence of thyroid nodules in a population occupationally exposed to radiation, in hospitals of Isfahan city."nPatients and Methods: In this case-control study, the prevalence of thyroid nodules in radiation exposed workers was determined by ultrasonography. The control group was selected from a community ...

  8. Evaluation of diffuse thyroid diseases and thyroid nodules by CT

    International Nuclear Information System (INIS)

    Okamoto, Kyoko; Imanishi, Yoshimasa; Nakaji, Shunsuke; Shinagawa, Toshihito

    2007-01-01

    Imanishi et al. have previously reported that the changes in CT values reveal not only the change in iodine concentration in thyroid follicles, but also represent secondary changes in follicular content and follicular cells and/or interstitial structures. Thus, we performed thyroid CT without contrast material in 138 controls, 417 cases with diffuse thyroid diseases, and 279 cases with thyroid nodules, and evaluated the CT images based on the relation between the change in CT values and pathological changes. In 89% of the controls and 43% of patients with diffuse thyroid diseases, the thyroid CT revealed diffuse high density. In contrast, the 94% of thyroids that demonstrated diffuse low density were from patients with diffuse thyroid diseases. Eighty-four percent of malignant nodules and 64% of benign nodules had inhomogeneous densities, and only 26% of benign thyroid nodules had homogeneous density. However, 71% of nodules that showed high and low densities with regular and clear borders, and 82% of nodules that showed papillary proliferation in a cyst pattern were benign. Although only 58% of nodules with calcification were malignant, 66% of nodules with calcification in the central portion, and 86% of nodules with calcification of a disseminated and convergent pattern in distribution were malignant. Sixty-two percent of thyroids that surrounded nodules had chronic thyroiditis, hypoplasia and/or adenomatous goiter. Thus, unclear borders between a nodule and the surrounding thyroid tissue did not increase the possibility of malignancy. However, the unclear and/or lobulated border between a nodule and extra thyroid tissue increased the possibility of malignancy. We concluded that thyroid CT without contrast material is useful for the diagnosis of thyroid diseases. (author)

  9. THE STUDY OF CLINICAL PRESENTATION OF SOLITARY NODULE THYROID

    Directory of Open Access Journals (Sweden)

    Lakshmikanthan Premalatha

    2017-07-01

    Full Text Available BACKGROUND Thyroid disorders are the most common endocrine disorder seen in clinical practice and solitary thyroid nodule is one of the common presentations of thyroid disease. A discrete swelling in an otherwise impalpable gland is termed isolated or solitary nodule of thyroid.1 The prevalence of thyroid nodule increases from near zero at 15 years to 50% by about 60 to 65 years on sonography. At most 10% of these nodules are palpable even by experienced clinicians. This study is about the clinical presentation, histopathology and management of solitary nodule thyroid in MGM GH Tiruchirappalli. AIMS AND OBJECTIVES- To determine the age and sex incidence among the cases of solitary nodule thyroid. To study the percentage of euthyroid, hypothyroid or hyperthyroid state in patients presenting with solitary nodule thyroid. To study the proportion of malignant and benign cases among the solitary nodule thyroid at M.G.M. Govt. Hospital, Tiruchirappalli. MATERIALS AND METHODS This study includes 58 cases of solitary nodule of thyroid noted during the period Jan 2016-Dec 2016. Factors were tabulated and analysed statistically. RESULTS From the present study, the mean age at presentation found to be 42.5 years with preponderance to females. Because of periods of fluctuations in the demands of the hormonal requirement in female in their life cycle (puberty, menstrual cycles, pregnancy, menopause, the chances of thyroid nodule formation are very high as compared with male counterparts. From the study, distribution of malignancy is about 10.34. The incidence of malignancy found to be 12%, sensitivity is 87.5%, specificity is 100% for FNAC and HPE. CONCLUSION Majority of the patients are between 30-49 years of age. Incidence of solitary thyroid nodule is more common in female. Female: male ratio is almost about 15:1 Commonest symptom is swelling over anterior or lateral aspect of neck Among the benign lesion dominant nodule is most common and papillary and

  10. Indian exploration for polymetallic nodules in the central Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    ShyamPrasad, M.

    depths between 4000 – 6000 metres, low rates of sedimentation, source supply of metals. Fig. 1. Various ocean basins in the Indian Ocean which show presence of manganese nodules. Of these, the Central Indian Ocean Basin has proved... demand and supply equations. One important parameter that one needs to consider is that there is no known nodule exploitation system developed on a commercial scale at the moment and also that all large nodule deposits are 57 beyond the EEZ...

  11. Multimodal imaging of choroidal nodules in neurofibromatosis type-1

    Directory of Open Access Journals (Sweden)

    Vinod Kumar

    2018-01-01

    Full Text Available Choroidal nodules in neurofibromatosis type-1 are common and are best imaged with near-infrared reflectance (NIR imaging. The authors describe swept-source optical coherence tomography angiography (SSOCTA of choroidal nodules. These nodules are seen as hyperflow areas on SSOCTA and correlate well to bright patches on NIR imaging. The utility of multicolor scanning laser imaging in detecting these abnormalities is also described.

  12. WATER STRESS RESPONSE ON THE ENZYMATIC ACTIVITY IN COWPEA NODULES

    Directory of Open Access Journals (Sweden)

    Figueiredo Márcia do Vale B.

    2001-01-01

    Full Text Available A greenhouse experiment was carried out aiming to study the effect of water stress on metabolic activity of cowpea nodules at different plant development stages. Cowpea plants were grown in pots with yellow latosol soil under three different matric potentials treatments: -7.0 (control-S1, -70.0 (S2 and <-85.0 KPa (S3. The experimental design was randomized blocks with sub-divided plots, each plot containing a different degree of water stress, divided in sub-plots for the four different developmental stages: E1 (0-15, E2 (15-30, E3 (20-35 and E4 (30-45 days after emmergence. Water stress treatments were applied by monitoring soil water potential using a set of porous cups. The effect of water stress was most harmful to cowpea when it was applied at E2 than at other symbiotic process stages. Shoot/root ratio decreased from 2.61 to 2.14 when matric potential treatment was <-85.0 and -70.0 KPa respectively. There was a reduction in the glutamine synthetase activity and phosphoenolpyruvate carboxilase activity with increased stress, while glutamine synthase activity was the enzyme most sensitive to water stress. Glutamate dehydrogenase activity increased in more negative matric potential, indicating that this enzyme is sufficiently activitye under water stress.

  13. Subsolid pulmonary nodules: imaging evaluation and strategic management.

    Science.gov (United States)

    Godoy, Myrna C B; Sabloff, Bradley; Naidich, David P

    2012-07-01

    Given the higher rate of malignancy of subsolid pulmonary nodules and the considerably lower growth rate of ground-glass nodules (GGNs), dedicated standardized guidelines for management of these nodules have been proposed, including long-term low-dose computed tomography (CT) follow-up (≥3 years). Physicians must be familiar with the strategic management of subsolid pulmonary nodules, and should be able to identify imaging features that suggest invasive adenocarcinoma requiring a more aggressive management. Low-dose CT screening studies for early detection of lung cancer have increased our knowledge of pulmonary nodules, and in particular our understanding of the strong although imperfect correlation of the subsolid pulmonary nodules, including pure GGNs and part-solid nodules, with the spectrum of preinvasive to invasive lung adenocarcinoma. Serial CT imaging has shown stepwise progression in a subset of these nodules, characterized by increase in size and density of pure GGNs and development of a solid component, the latter usually indicating invasive adenocarcinoma. There is close correlation between the CT features of subsolid nodules (SSNs) and the spectrum of lung adenocarcinoma. Standardized guidelines are suggested for management of SSNs.

  14. Asymptomatic Papulo-nodules Localized to One Finger

    Science.gov (United States)

    Rambhia, Kinjal D; Khopkar, Uday S

    2015-01-01

    Subcutaneous or deep granuloma annulare is a benign asymptomatic condition characterized by firm asymptomatic nodules in deep subcutaneous tissues that may be associated with intradermal lesions. A 53-year-old female presented with asymptomatic skin-colored, firm nodules over the right ring finger. Histopathology revealed a palisading granuloma with central degenerated collagen and mucin deposition in the dermis suggestive of granuloma annulare. Isolated and unilateral involvement of a single digit with clusters of nodules of subcutaneous granuloma annulare (GA) in an adult is rare and differentiation from its simulator rheumatoid nodule is essential. PMID:26538728

  15. Hyper-functioning Thyroid Nodule with Scintigraphic Owl's Eye Appearance

    International Nuclear Information System (INIS)

    Al-Kordi, R.S.; Elgazzar, A.H.

    2006-01-01

    Hyper-functioning thyroid nodules may produce various scintigraphic appearances on thyroid scans. Autonomously hyper functioning thyroid nodules invariably demonstrate degenerative changes. These changes may give rise to central or less commonly peripheral photopenic areas on a thyroid scan within otherwise a hot nodule. In this report we present a case of hyper functioning autonomous nodule with peripheral degeneration and residual central functioning tissue giving the appearance of an owl's eye. Although rare, this pattern can be seen in a variety of benign and malignant thyroid conditions. (author)

  16. Automatic Solitary Lung Nodule Detection in Computed Tomography Images Slices

    Science.gov (United States)

    Sentana, I. W. B.; Jawas, N.; Asri, S. A.

    2018-01-01

    Lung nodule is an early indicator of some lung diseases, including lung cancer. In Computed Tomography (CT) based image, nodule is known as a shape that appears brighter than lung surrounding. This research aim to develop an application that automatically detect lung nodule in CT images. There are some steps in algorithm such as image acquisition and conversion, image binarization, lung segmentation, blob detection, and classification. Data acquisition is a step to taking image slice by slice from the original *.dicom format and then each image slices is converted into *.tif image format. Binarization that tailoring Otsu algorithm, than separated the background and foreground part of each image slices. After removing the background part, the next step is to segment part of the lung only so the nodule can localized easier. Once again Otsu algorithm is use to detect nodule blob in localized lung area. The final step is tailoring Support Vector Machine (SVM) to classify the nodule. The application has succeed detecting near round nodule with a certain threshold of size. Those detecting result shows drawback in part of thresholding size and shape of nodule that need to enhance in the next part of the research. The algorithm also cannot detect nodule that attached to wall and Lung Chanel, since it depend the searching only on colour differences.

  17. Lotus japonicus nodulation requires two GRAS domain regulators, one of which is functionally conserved in a non-legume

    DEFF Research Database (Denmark)

    Heckmann, Anne Birgitte Lau; Lombardo, Fabien; Miwa, Hiroki

    2006-01-01

    A new nodulation-defective mutant of Lotus japonicus does not initiate nodule cortical cell division in response to Mesorhizobium loti, but induces root hair deformation, Nod factor-induced calcium spiking, and mycorrhization. This phenotype, together with mapping data, suggested that the mutation...... could be in the ortholog of the Medicago truncatula NSP1 gene (MtNSP1). The sequence of the orthologous gene (LjNSP1) in the L. japonicus mutant (Ljnsp1-1) revealed a mutation causing a premature stop resulting in loss of the C-terminal 23 amino acids. We also sequenced the NSP2 gene from L. japonicus...

  18. Root resorption

    DEFF Research Database (Denmark)

    Kjaer, Inger

    2014-01-01

    Introduction: This paper summarizes the different conditions, which have a well-known influence on the resorption of tooth roots, exemplified by trauma and orthodontic treatment. The concept of the paper is to summarize and explain symptoms and signs of importance for avoiding resorption during...... orthodontic treatment. The Hypothesis: The hypothesis in this paper is that three different tissue layers covering the root in the so-called periroot sheet can explain signs and symptoms of importance for avoiding root resorption during orthodontic treatment. These different tissue layers are; outermost......-an ectodermal tissue layer (Malassez′s epithelium), a middle layer-composed by the collagen-mesodermal tissue layer, and an innermost root-close innervation layer. Abnormalities in one of these tissue layers are thought to cause inflammatory processes in the periodontal membrane comparable to inflammatory...

  19. Licorice Root

    Science.gov (United States)

    ... T U V W X Y Z Licorice Root Share: On This Page Background How Much Do ... This fact sheet provides basic information about licorice root—common names, usefulness and safety, and resources for ...

  20. Comparison of muscle-to-nodule and parenchyma-to-nodule strain ratios in the differentiation of benign and malignant thyroid nodules: Which one should we use?

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, Ramazan, E-mail: raydin1984@hotmail.com [Department of Radiology, Samsun Education and Research Hospital, Samsun (Turkey); Elmali, Muzaffer, E-mail: muzafel@yahoo.com.tr [Department of Radiology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Polat, Ahmet Veysel, E-mail: veyselp@hotmail.com [Department of Radiology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Danaci, Murat, E-mail: danacim55@yahoo.com [Department of Radiology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey); Akpolat, Ilkser, E-mail: ilkserakpolat@yahoo.com [Department of Pathology, Ondokuz Mayis University, Faculty of Medicine, Samsun (Turkey)

    2014-03-15

    Objective: The aim of this study is to investigate the diagnostic accuracy of muscle-to-nodule strain ratio (MNSR) in the differentiation of benign and malignant thyroid nodules and to see if there was a difference between MNSR and parenchyma-to-nodule strain ratios (PNSR) in diagnosis. Methods: A total of 106 consecutive patients (88 women and 18 men; age range 19–79 years) with thyroid nodules were prospectively examined using ultrasound and sonoelastography before the fine-needle aspiration biopsy. The mean MNSR and PNSR were calculated for each nodule and the elasticity score was determined according to four-point scoring system. Results: According to the four-point scoring system, 44 of the 83 benign nodules had a score of one or two while 22 of the 23 malignant nodules had a score of three or four (p < 0.001). Using ROC analysis, the best cutoff point for MNSR 1.85 and for PNSR 3.14 was calculated. The sensitivity and specificity for the MNSR were 95.6%, 92.8%, respectively; for the PNSR were 95.6%, 93.4%, respectively, when the best cutoff points were used (p < 0.001). The κ value for the PNSR and MNSR methods was 0.87, which indicated an almost perfect agreement (p < 0.001). Conclusions: Sonoelastography has a high diagnostic accuracy in the differentiation of benign and malignant thyroid nodules. There was no significant difference between MNSR and PNSR in the differentiation of benign and malignant thyroid nodules. Therefore, we think that MNSR could safely be used in situations where PNSR could not be used.

  1. Vasculature surrounding a nodule: A novel lung cancer biomarker.

    Science.gov (United States)

    Wang, Xiaohua; Leader, Joseph K; Wang, Renwei; Wilson, David; Herman, James; Yuan, Jian-Min; Pu, Jiantao

    2017-12-01

    To investigate whether the vessels surrounding a nodule depicted on non-contrast, low-dose computed tomography (LDCT) can discriminate benign and malignant screen detected nodules. We collected a dataset consisting of LDCT scans acquired on 100 subjects from the Pittsburgh Lung Screening study (PLuSS). Fifty subjects were diagnosed with lung cancer and 50 subjects had suspicious nodules later proven benign. For the lung cancer cases, the location of the malignant nodule in the LDCT scans was known; while for the benign cases, the largest nodule in the LDCT scan was used in the analysis. A computer algorithm was developed to identify surrounding vessels and quantify the number and volume of vessels that were connected or near the nodule. A nonparametric receiver operating characteristic (ROC) analysis was performed based on a single nodule per subject to assess the discriminability of the surrounding vessels to provide a lung cancer diagnosis. Odds ratio (OR) were computed to determine the probability of a nodule being lung cancer based on the vessel features. The areas under the ROC curves (AUCs) for vessel count and vessel volume were 0.722 (95% CI=0.616-0.811, plung cancer group 9.7 (±9.6) compared to the non-lung cancer group 4.0 (±4.3) CONCLUSION: Our preliminary results showed that malignant nodules are often surrounded by more vessels compared to benign nodules, suggesting that the surrounding vessel characteristics could serve as lung cancer biomarker for indeterminate nodules detected during LDCT lung cancer screening using only the information collected during the initial visit. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. VATS intraoperative tattooing to facilitate solitary pulmonary nodule resection

    Directory of Open Access Journals (Sweden)

    Boutros Cherif

    2008-03-01

    Full Text Available Abstract Introduction Video-assisted thoracic surgery (VATS has become routine and widely accepted for the removal of solitary pulmonary nodules of unknown etiology. Thoracosopic techniques continue to evolve with better instruments, robotic applications, and increased patient acceptance and awareness. Several techniques have been described to localize peripheral pulmonary nodules, including pre-operative CT-guided tattooing with methylene blue, CT scan guided spiral/hook wire placement, and transthoracic ultrasound. As pulmonary surgeons well know, the lung and visceral pleura may appear featureless on top of a pulmonary nodule. Case description This paper presents a rapid, direct and inexpensive approach to peripheral lung lesion resection by marking the lung parenchyma on top of the nodule using direct methylene blue injection. Methods In two patients with peripherally located lung nodules (n = 3 scheduled for VATS, we used direct methylene blue injection for intraoperative localization of the pulmonary nodule. Our technique was the following: After finger palpation of the lung, a spinal 25 gauge needle was inserted through an existing port and 0.1 ml of methylene blue was used to tattoo the pleura perpendicular to the localized nodule. The methylene blue tattoo immediately marks the lung surface over the nodule. The surgeon avoids repeated finger palpation, while lining up stapler, graspers and camera, because of the visible tattoo. Our technique eliminates regrasping and repalpating the lung once again to identify a non marked lesion. Results Three lung nodules were resected in two patients. Once each lesion was palpated it was marked, and the area was resected with security of accurate localization. All lung nodules were resected in totality with normal lung parenchymal margins. Our technique added about one minute to the operative time. The two patients were discharged home on the second postoperative day, with no morbidity. Conclusion

  3. Acoustic radiation force impulse imaging for differentiation of thyroid nodules.

    Directory of Open Access Journals (Sweden)

    Joerg Bojunga

    Full Text Available BACKGROUND: Acoustic Radiation Force Impulse (ARFI-Imaging is an ultrasound-based elastography method enabling quantitative measurement of tissue stiffness. The aim of the present study was to evaluate sensitivity and specificity of ARFI-imaging for differentiation of thyroid nodules and to compare it to the well evaluated qualitative real-time elastography (RTE. METHODS: ARFI-imaging involves the mechanical excitation of tissue using acoustic pulses to generate localized displacements resulting in shear-wave propagation which is tracked using correlation-based methods and recorded in m/s. Inclusion criteria were: nodules ≥5 mm, and cytological/histological assessment. All patients received conventional ultrasound, real-time elastography (RTE and ARFI-imaging. RESULTS: One-hundred-fifty-eight nodules in 138 patients were available for analysis. One-hundred-thirty-seven nodules were benign on cytology/histology, and twenty-one nodules were malignant. The median velocity of ARFI-imaging in the healthy thyroid tissue, as well as in benign and malignant thyroid nodules was 1.76 m/s, 1.90 m/s, and 2.69 m/s, respectively. While no significant difference in median velocity was found between healthy thyroid tissue and benign thyroid nodules, a significant difference was found between malignant thyroid nodules on the one hand and healthy thyroid tissue (p = 0.0019 or benign thyroid nodules (p = 0.0039 on the other hand. No significant difference of diagnostic accuracy for the diagnosis of malignant thyroid nodules was found between RTE and ARFI-imaging (0.74 vs. 0.69, p = 0.54. The combination of RTE with ARFI did not improve diagnostic accuracy. CONCLUSIONS: ARFI can be used as an additional tool in the diagnostic work up of thyroid nodules with high negative predictive value and comparable results to RTE.

  4. Genome sequence of the Trifolium rueppellianum -nodulating Rhizobium leguminosarum bv. trifolii strain WSM2012.

    Science.gov (United States)

    Reeve, Wayne; Melino, Vanessa; Ardley, Julie; Tian, Rui; De Meyer, Sofie; Terpolilli, Jason; Tiwari, Ravi; Yates, Ronald; O’Hara, Graham; Howieson, John; Ninawi, Mohamed; Held, Brittany; Bruce, David; Detter, Chris; Tapia, Roxanne; Han, Cliff; Wei, Chia-Lin; Huntemann, Marcel; Han, James; Chen, I-Min; Mavromatis, Konstantinos; Markowitz, Victor; Szeto, Ernest; Ivanova, Natalia; Mikhailova, Natalia; Pagani, Ioanna; Pati, Amrita; Goodwin, Lynne; Woyke, Tanja; Kyrpides, Nikos

    2013-01-01

    Rhizobium leguminosarum bv. trifolii WSM2012 (syn. MAR1468) is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from an ineffective root nodule recovered from the roots of the annual clover Trifolium rueppellianum Fresen growing in Ethiopia. WSM2012 has a narrow, specialized host range for N2-fixation. Here we describe the features of R. leguminosarum bv. trifolii strain WSM2012, together with genome sequence information and annotation. The 7,180,565 bp high-quality-draft genome is arranged into 6 scaffolds of 68 contigs, contains 7,080 protein-coding genes and 86 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program. PMID:24976885

  5. Autonomous nodule of the thyroid: correlation of patient age, nodule size, and functional status

    International Nuclear Information System (INIS)

    Blum, M.; Shenkman, L.; Hollander, C.S.

    1975-01-01

    In light of new techniques for measuring circulating thyroid hormones and for studying the thyroid gland, we present our experience with 35 patients with solitary autonomous nodules of the thyroid to define more precisely the clinical course of patients with this disorder. The patients ranged in age from 19 to 80 years and 31 of the 35 were female. Younger patients were generally euthyroid and sought attention because of a thyroid mass; virtually all older patients were hyperthyroid. Eighteen had obvious clinical features of hyperthyroidism and 5 over age 70 had apathetic hyperthyroidism; all 5 of the elderly and 13 of the 18 under age 70 had elevated thyroxine (T 4 ) and triiodothyronine (T 3 ) levels. Isolated elevation of T 3 and elevated basal metabolic rate were observed in 5 previously untreated clinically hyperthyroid young patients. In each of these, thyroid uptake of 131 I was not suppressible with exogenous T 3 and BMR was elevated in those tested. Two elderly patients, who had previously been treated for conventional hyperthyroidism with radioactive iodine, had T 3 toxicosis when hyperthyroidism recurred. There was a strong positive correlation between the age of the patient, the size of the nodule and the thyroid functional state. The mean area of the nodules projected on 131 I rectilinear scan for euthyroid patients was 5.1 cm 2 . The mean area of the nodules in hyperthyroid subjects was significantly higher, 13.4 cm 2 in patients with T 3 toxicosis and 19.3 cm 2 in subjects with conventional hyperthyroidism. Progression from a euthyroid state to hyperthyroidism was observed in four patients. One of these became thyrotoxic within days after an injection of iodinated contrast medium. Spontaneous resolution of nodules occurred in two patients

  6. Genome sequence of the clover-nodulating Rhizobium leguminosarum bv. trifolii strain SRDI943.

    Science.gov (United States)

    Reeve, Wayne; Drew, Elizabeth; Ballard, Ross; Melino, Vanessa; Tian, Rui; De Meyer, Sofie; Brau, Lambert; Ninawi, Mohamed; Daligault, Hajnalka; Davenport, Karen; Erkkila, Tracy; Goodwin, Lynne; Gu, Wei; Munk, Christine; Teshima, Hazuki; Xu, Yan; Chain, Patrick; Kyrpides, Nikos

    2013-01-01

    Rhizobium leguminosarum bv. trifolii SRDI943 (strain syn. V2-2) is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Trifolium michelianum Savi cv. Paradana that had been grown in soil collected from a mixed pasture in Victoria, Australia. This isolate was found to have a broad clover host range but was sub-optimal for nitrogen fixation with T. subterraneum (fixing 20-54% of reference inoculant strain WSM1325) and was found to be totally ineffective with the clover species T. polymorphum and T. pratense. Here we describe the features of R. leguminosarum bv. trifolii strain SRDI943, together with genome sequence information and annotation. The 7,412,387 bp high-quality-draft genome is arranged into 5 scaffolds of 5 contigs, contains 7,317 protein-coding genes and 89 RNA-only encoding genes, and is one of 100 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project. PMID:24976880

  7. api, A novel Medicago truncatula symbiotic mutant impaired in nodule primordium invasion.

    Science.gov (United States)

    Teillet, Alice; Garcia, Joseph; de Billy, Françoise; Gherardi, Michèle; Huguet, Thierry; Barker, David G; de Carvalho-Niebel, Fernanda; Journet, Etienne-Pascal

    2008-05-01

    Genetic approaches have proved to be extremely useful in dissecting the complex nitrogen-fixing Rhizobium-legume endosymbiotic association. Here we describe a novel Medicago truncatula mutant called api, whose primary phenotype is the blockage of rhizobial infection just prior to nodule primordium invasion, leading to the formation of large infection pockets within the cortex of noninvaded root outgrowths. The mutant api originally was identified as a double symbiotic mutant associated with a new allele (nip-3) of the NIP/LATD gene, following the screening of an ethylmethane sulphonate-mutagenized population. Detailed characterization of the segregating single api mutant showed that rhizobial infection is also defective at the earlier stage of infection thread (IT) initiation in root hairs, as well as later during IT growth in the small percentage of nodules which overcome the primordium invasion block. Neither modulating ethylene biosynthesis (with L-alpha-(2-aminoethoxyvinylglycine or 1-aminocyclopropane-1-carboxylic acid) nor reducing ethylene sensitivity in a skl genetic background alters the basic api phenotype, suggesting that API function is not closely linked to ethylene metabolism or signaling. Genetic mapping places the API gene on the upper arm of the M. truncatula linkage group 4, and epistasis analyses show that API functions downstream of BIT1/ERN1 and LIN and upstream of NIP/LATD and the DNF genes.

  8. Guideline on management of solitary pulmonary nodule.

    Science.gov (United States)

    Álvarez Martínez, Carlos J; Bastarrika Alemañ, Gorka; Disdier Vicente, Carlos; Fernández Villar, Alberto; Hernández Hernández, Jesús R; Maldonado Suárez, Antonio; Moreno Mata, Nicolás; Rosell Gratacós, Antoni

    2014-07-01

    The aim of the proposed recommendations is be a tool to facilitate decision-making in patients with a solitary pulmonary nodule (SPN). For an optimal decision, accessibility to the different diagnostics techniques and patient preferences need to be incorporated. The first assessment, which includes a chest computed tomography scan, separates a group of patients with extrapulmonary neoplasm or a high surgical risk who require individualized management. Another two groups of patients are patients with SPN up to 8mm and those who have a subsolid SPN, for which specific recommendations are established. SPN larger than 8mm are classified according to their probability of malignancy into low (less than 5%), where observation is recommended, high (higher than 65%), which are managed with a presumptive diagnosis of localized stage carcinoma, and intermediate, where positron emission tomography-computed tomography has high yield for reclassifying them into high or low probability. In cases of intermediate or high probability of malignancy, transbronchial needle aspiration or biopsy of the nodule may be an option. Radiologic observation with low radiation computed tomography without contrast is recommended in SPN with low probability of malignancy, and resection with videothoracoscopy in undiagnosed cases with intermediate or high probability of malignancy. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.

  9. Computerized detection of lung nodules in digital chest radiographs

    International Nuclear Information System (INIS)

    Giger, M.L.; Doi, K.; MacMahon, H.

    1987-01-01

    Detection of cancerous lung nodules in chest radiographs is one of the more important tasks performed by a radiologist. In addition, the ''miss rate'' associated with the radiographic detection of lung nodules is approximately 30%. A computerized scheme that alerts the radiologist to possible locations of lung nodules should allow this number of false-negative diagnoses to be reduced. The authors are developing a computer-aided nodule detection scheme based on a difference image approach. They attempt to eliminate the camouflaging background structure of the normal lung anatomy by creating, from a single-projection chest image, two images: one in which the signal-to-noise ratio (SNR) of the nodule is maximized and another in which that SNR is suppressed while the processed background remains essentially the same. Thus, the difference between these two processed images should consist of the nodule superimposed on a relatively uniform background in which the detection task may be simplified. This difference image approach is fundamentally different from conventional subtraction techniques (e.g., temporal or dual-energy subtraction) in that the two images which are subtracted arise from the same single-projection chest radiograph. Once the difference image is obtained, thresholding is performed along with tests for circularity, size and growth in order to extract the nodules. It should be noted that once an original chest image is input to the computer the nodule detection process is totally automated

  10. The relationship between occupational radiation exposure and thyroid nodules

    Directory of Open Access Journals (Sweden)

    Atoosa Adibi

    2012-01-01

    Full Text Available Background: Considering that thyroid nodules and thyroid cancer occur more frequently in people chronically exposed to radiation, the aim of this study was to evaluate the prevalence of thyroid nodules in a population occupationally exposed to radiation in hospitals of Isfahan, Iran. Materials and Methods: In this case-control study, the prevalence of thyroid nodules in staff members occupationally exposed to radiation was determined by ultrasonography. The results were compared with the results of another study among the adult population of Isfahan which selected by cluster random sampling method. The 2 studied groups were matched according to sex and age. Results: The case and control groups included 124 and 471 persons, respectively. The prevalence of thyroid nodules in the case and control groups was 22.6% and 24.6%, respectively (p > 0.05. Although thyroid nodules were significantly more prevalent in females in the control group, no such difference was observed between females and males of the case group (p > 0.05. The number of thyroid nodules (single or multiple and calcification were not different between the two groups (p > 0.05. In addition, hypoechogenicity of thyroid nodules was not different between the two groups for (p > 0.05. Conclusion: In our study, there was not any correlation between chronic occupational exposure to low dose of radiation and the risk of developing thyroid nodules. Further studies with larger sample sizes, at different doses of radiation, and considering iodine status and thyroid function are thus required.

  11. The relationship between occupational radiation exposure and thyroid nodules

    Science.gov (United States)

    Adibi, Atoosa; Rezazade, Afshin; Hovsepian, Silva; Koohi, Razie; Hosseini, Mohsen

    2012-01-01

    Background: Considering that thyroid nodules and thyroid cancer occur more frequently in people chronically exposed to radiation, the aim of this study was to evaluate the prevalence of thyroid nodules in a population occupationally exposed to radiation in hospitals of Isfahan, Iran. Materials and Methods: In this case-control study, the prevalence of thyroid nodules in staff members occupationally exposed to radiation was determined by ultrasonography. The results were compared with the results of another study among the adult population of Isfahan which selected by cluster random sampling method. The 2 studied groups were matched according to sex and age. Results: The case and control groups included 124 and 471 persons, respectively. The prevalence of thyroid nodules in the case and control groups was 22.6% and 24.6%, respectively (p > 0.05). Although thyroid nodules were significantly more prevalent in females in the control group, no such difference was observed between females and males of the case group (p > 0.05). The number of thyroid nodules (single or multiple) and calcification were not different between the two groups (p > 0.05). In addition, hypoechogenicity of thyroid nodules was not different between the two groups for (p > 0.05). Conclusion: In our study, there was not any correlation between chronic occupational exposure to low dose of radiation and the risk of developing thyroid nodules. Further studies with larger sample sizes, at different doses of radiation, and considering iodine status and thyroid function are thus required. PMID:23626606

  12. A case of cyclist's nodule in a female patient

    African Journals Online (AJOL)

    ere are few reported cases of cyclist's nodule in females. e condition has thus lent itself to synonyms such as third, supernumerary or ... We report the imaging ndings of a perineal nodule in a 29-year-old female patient who is a known cyclist, and discuss ... from vibration and friction between the ischial tuberosities and the.

  13. Is genetic selection for skin nodule traits of ostriches feasible ...

    African Journals Online (AJOL)

    Preliminary genetic parameters for nodule traits of ostrich skins were estimated to examine whether genetic improvement of skin quality is feasible. Average nodule size and density per dmยฒ were determined on five localities on each of 439 ostrich skins. An animal model with random animal and skin permanent ...

  14. Uranium in Pacific Deep-Sea Sediments and Manganese Nodules

    DEFF Research Database (Denmark)

    Kunzendorf, Helmar; Pluger, W. L.; Friedrich, G. H.

    1983-01-01

    A total of 1344 manganese nodules and 187 pelagic sediments from 9 areas in the North and the South Pacific were analyzed for U by the delayed-neutron counting technique. A strong positive correlation between U and Fe in nodules and sediments suggests a co-precipitative removal from sea water int...

  15. Variation in nodulation and growth of groundnut ( Arachis hypogaea ...

    African Journals Online (AJOL)

    Improving biological nitrogen fixation through legume nodulating bacteria (LNB) inoculation requires knowledge on the abundance and effectiveness of indigenous population in the ferralsols. Nodulation of groundnut was examined under pots experiment in four location sites of the Humid-forest zone: Bertoua in the East; ...

  16. Occurrence of Nodulation in Leguminous Trees in Kenya | Anyango ...

    African Journals Online (AJOL)

    Exploitation of the potential for nitrogen fixing trees, soil improvement and multipurpose use, requires a good knowledge of their nodulation capabilities and agrosilvicultural manipulation. Nitrogen Fixation in some nodulated species can be maximized by inoculation with effective Rhizobium strains. This study reports the ...

  17. Bean nodulation patterns in soils of different texture at Morogoro ...

    African Journals Online (AJOL)

    This study was designed to examine the, relationship between nodulation in a bean-Rhizobium system in three soils of varying texture and % recovery of rhizobia I cells immediately after inoculation into such soils. Effects of inoculation methods (seed pelleting versus soil inoculation) on nodulation and plant growth were ...

  18. Bean Nodulation Patterns in Soils of Different Texture at Morogoro ...

    African Journals Online (AJOL)

    Abstract. This study was designed to examine the, relationship between nodulation in a bean-Rhizobium system in three soils of varying texture and % recovery of rhizobia I cells immediately after in- oculation into such soils. Effects of inoculation methods (seed pelleting versus soil inocula- tion) on nodulation and plant ...

  19. 3D pulmonary nodules detection using fast marching segmentation ...

    African Journals Online (AJOL)

    This paper proposes an automated computer aided diagnosis system for detection of pulmonary nodules based on three dimensional (3D) structures. Lung ... The proposed detection methodology can give the accuracy of 92%. Keywords: lung cancer; pulmonary nodule; fast marching; 3D features; random forest classifier.

  20. Nodulin gene expression during soybean (Glycine max) nodule development.

    NARCIS (Netherlands)

    Gloudemans, T.; Vries, de S.; Bussink, H.J.; Malik, N.S.A.; Franssen, H.; Louwerse, J.; Bisseling, T.

    1987-01-01

    In vitro translation products of total RNA isolated from soybean nodules at successive stages of nodule development were analyzed by two-dimensional gel electrophoresis. In that way the occurrence of over 20 mRNAs specifically transcribed from nodulin genes was detected. The nodulin genes could be

  1. System for automatic detection of lung nodules exhibiting growth

    Science.gov (United States)

    Novak, Carol L.; Shen, Hong; Odry, Benjamin L.; Ko, Jane P.; Naidich, David P.

    2004-05-01

    Lung nodules that exhibit growth over time are considered highly suspicious for malignancy. We present a completely automated system for detection of growing lung nodules, using initial and follow-up multi-slice CT studies. The system begins with automatic detection of lung nodules in the later CT study, generating a preliminary list of candidate nodules. Next an automatic system for registering locations in two studies matches each candidate in the later study to its corresponding position in the earlier study. Then a method for automatic segmentation of lung nodules is applied to each candidate and its matching location, and the computed volumes are compared. The output of the system is a list of nodule candidates that are new or have exhibited volumetric growth since the previous scan. In a preliminary test of 10 patients examined by two radiologists, the automatic system identified 18 candidates as growing nodules. 7 (39%) of these corresponded to validated nodules or other focal abnormalities that exhibited growth. 4 of the 7 true detections had not been identified by either of the radiologists during their initial examinations of the studies. This technique represents a powerful method of surveillance that may reduce the probability of missing subtle or early malignant disease.

  2. Solitary pulmonary nodule: radiologic features and diagnostic approach

    International Nuclear Information System (INIS)

    Rodriguez Cambronero, Luis Enrique

    2012-01-01

    A literature review is conducted on the solitary pulmonary nodule, to determine the diagnostic methods and specific characteristics. The diagnostic methods used have been: chest radiography, computed tomography, positron emission tomography and magnetic resonance imaging. The radiological features are defined: location, size, definition of contours or edges (margins), densitometric and attenuation characteristics, cavitation, air bronchogram, growth, doubling time, satellite nodules, nutrient vessels [es

  3. Vocal nodules in a colombian teachers group with dysphonia

    Directory of Open Access Journals (Sweden)

    Andrés Felipe Alvarado Díaz

    2013-12-01

    Full Text Available Objectives: This study determined the prevalence of vocal nodules associated with dysphonia in teachers aged from 35 to 65 years, taking into consideration both individual and occupational variables. Methodology: Descriptive study that included the information contained in 262 medical records of teachers diagnosed with dysphonia in occupational health consultations at the institutions that provide health services in Bogotá, Colombia from March 2009 to March 2012. The presence of laryngeal nodules was based on the findings of a nasofibrolaryngoscopy procedure. Results: Nodules were found in 67 teachers, which corresponded to a rate of 25.5%, being apparently (highest observed rates associated primarily with the following variables: females, ages from 45 to 54 years, bilateral nodules, and teaching position (preschool and physical education. Of the teachers with nodules, 76.1% had fewer than five doctor's appointments, and 75% had more than 90 days of sick leave. Conclusion: A high percentage of teachers have vocal nodules associated with dysphonia. This may be apparently related to different variables such as sex, type of nodule, area and teaching position. Was observed only a statistically significant association among presence of nodules and age (p=0.018. In addition this disorder generates a large number of incapacities and employee absenteeism.

  4. Management of subsolid pulmonary nodules in CT lung cancer screening

    NARCIS (Netherlands)

    Heuvelmans, Marjolein A.; Oudkerk, Matthijs

    The distinct appearance and behavior of subsolid pulmonary nodules (SSNs) has resulted in separate recommendations for the management of solitary SSNs, both for incidentally detected as well as for screen detected nodules. However, these guidelines have been based primarily on expert opinion.

  5. Internal microfeatures of manganese nodules from the Central Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.

    whereas nodules from the abyssal plains show prominent, well-developed columnar structures. Features such as botryoids and fractures filled with Fe and Mn oxides are more common in the nodules of abyssal plains whereas the clay content and clastic grains...

  6. Danish Rhizobium leguminosarum strains nodulating ‘Afghanistan’ pea (Pisum sativum)

    DEFF Research Database (Denmark)

    Jensen, Erik Steen; Sørensen, Lasse Holst; Engvild, Kjeld Christensen

    1986-01-01

    A wild pea (Pisum sativum L.) native to Afghanistan normally known to be resisant to nodulation with European strains of Rhizobium leguminosarum was nodulated early and effectively in field soil in Denmark. Isolates from nodules formed effective nodules abundantly on 'Afghanistan' on reinfection ...... pattern with Rhizobium leguminosarum strains isolated from a modern pea variety cultivated in the same field.......A wild pea (Pisum sativum L.) native to Afghanistan normally known to be resisant to nodulation with European strains of Rhizobium leguminosarum was nodulated early and effectively in field soil in Denmark. Isolates from nodules formed effective nodules abundantly on 'Afghanistan' on reinfection...

  7. Quantitative image measurements for outcome analysis of lung nodule treatment

    Science.gov (United States)

    Zhu, Xiaoming; Lee, Ki-Nam; Wong, Stephen T. C.; Huang, H. K.

    1996-04-01

    In this study, we designed and implemented a temporal image database for outcome analysis of lung nodules based on spiral CT images. The software package is composed of three parts. They are, respectively, a database management system which stores patient image data and nodule information; a user-friendly graphical user interface which allows a user to interface with the image database; and image processing tools that are designed to segment out lung nodules in the CT image with a simple mouse click anywhere inside a nodule. The image database uses the relational Sybase database system. Patient images and nodule information are stored in separate tables. Software interface has been designed to allow a user to retrieve any patient study from the picture archiving and communication system into the image database.

  8. Effect of Rhizobium sp. BARIRGm901 inoculation on nodulation, nitrogen fixation and yield of soybean (Glycine max) genotypes in gray terrace soil.

    Science.gov (United States)

    Alam, Faridul; Bhuiyan, M A H; Alam, Sadia Sabrina; Waghmode, Tatoba R; Kim, Pil Joo; Lee, Yong Bok

    2015-01-01

    Soybean plants require high amounts of nitrogen, which are mainly obtained from biological nitrogen fixation. A field experiment was conducted by soybean (Glycine max) genotypes, growing two varieties (Shohag and BARI Soybean6) and two advanced lines (MTD10 and BGM02026) of soybean with or without Rhizobium sp. BARIRGm901 inoculation. Soybean plants of all genotypes inoculated with Rhizobium sp. BARIRGm901 produced greater nodule numbers, nodule weight, shoot and root biomass, and plant height than non-inoculated plants. Similarly, inoculated plants showed enhanced activity of nitrogenase (NA) enzyme, contributing to higher nitrogen fixation and assimilation, compared to non-inoculated soybean plants in both years. Plants inoculated with Rhizobium sp. BARIRGm901 also showed higher pod, stover, and seed yield than non-inoculated plants. Therefore, Rhizobium sp. BARIRGm901 established an effective symbiotic relationship with a range of soybean genotypes and thus increased the nodulation, growth, and yield of soybean grown in gray terrace soils in Bangladesh.

  9. Volumetric measurements of pulmonary nodules: variability in automated analysis tools

    Science.gov (United States)

    Juluru, Krishna; Kim, Woojin; Boonn, William; King, Tara; Siddiqui, Khan; Siegel, Eliot

    2007-03-01

    Over the past decade, several computerized tools have been developed for detection of lung nodules and for providing volumetric analysis. Incidentally detected lung nodules have traditionally been followed over time by measurements of their axial dimensions on CT scans to ensure stability or document progression. A recently published article by the Fleischner Society offers guidelines on the management of incidentally detected nodules based on size criteria. For this reason, differences in measurements obtained by automated tools from various vendors may have significant implications on management, yet the degree of variability in these measurements is not well understood. The goal of this study is to quantify the differences in nodule maximum diameter and volume among different automated analysis software. Using a dataset of lung scans obtained with both "ultra-low" and conventional doses, we identified a subset of nodules in each of five size-based categories. Using automated analysis tools provided by three different vendors, we obtained size and volumetric measurements on these nodules, and compared these data using descriptive as well as ANOVA and t-test analysis. Results showed significant differences in nodule maximum diameter measurements among the various automated lung nodule analysis tools but no significant differences in nodule volume measurements. These data suggest that when using automated commercial software, volume measurements may be a more reliable marker of tumor progression than maximum diameter. The data also suggest that volumetric nodule measurements may be relatively reproducible among various commercial workstations, in contrast to the variability documented when performing human mark-ups, as is seen in the LIDC (lung imaging database consortium) study.

  10. Impact of overexpression of cytosolic isoform of O-acetylserine sulfhydrylase on soybean nodulation and nodule metabolome

    Science.gov (United States)

    Nitrogen-fixing nodules, which are also major sites of sulfur assimilation, contribute significantly to the sulfur needs of the whole soybean plants. Nodules are the predominant sites for cysteine accumulation and the activity of O-acetylserine sulfhydrylase (OASS; also known as O-acetylserine(thio...

  11. Thirteen nodule-specific or nodule-enhanced genes encoding products homologous to cysteine cluster proteins or plant lipid transfer proteins are identified in Astragalus sinicus L. by suppressive subtractive hybridization.

    Science.gov (United States)

    Chou, Min-Xia; Wei, Xin-Yuan; Chen, Da-Song; Zhou, Jun-Chu

    2006-01-01

    Thirteen nodule-specific or nodule-enhanced genes have been revealed by suppressive subtractive hybridization (SSH) with two mRNA populations of infected and uninfected control roots of Astragalus sinicus. Eleven of them encode small polypeptides showing homology to cysteine cluster proteins (CCPs) that contain a putative signal peptide and conserved cysteine residues. Among these CCP-like genes, AsG257 codes for a homologue of the defensin 2 family and AsD255 contains a scorpion toxin-like domain at the C-terminus. Sequence analysis of a genomic AsD255 fragment which was isolated revealed that one intron separates the first exon encoding the signal peptide from the second exon encoding the cysteine cluster domain of this nodulin. Another two genes, AsE246 and AsIB259, encode two different products similar to lipid transfer proteins (LTPs). Virtual northern blot and reverse transcription-polymerase chain reaction (RT-PCR) analysis indicated that the other genes except AsIB259 and AsC2411 were expressed exclusively in inoculated roots and that their expression was 2-4 d later than that of the leghaemoglobin (Lb) gene during nodule development. Transcription of AsIB259 was also detected in uninfected control roots but with a significant decline in expression and a temporal expression similar to Lb. AsC2411 had a basal expression in control roots identified by RT-PCR. Sequence alignment showed that the putative proteins AsE246 and AsIB259 show lower homology with LTPs from legumes than with those from other plants.

  12. Predictive factors for malignancy in incidental pulmonary nodules detected in breast cancer patients at baseline CT

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, Mark M.; Mortani Barbosa, Eduardo J. [University of Pennsylvania, Division of Cardiothoracic Imaging, Department of Radiology, Perelman School of Medicine, Philadelphia, PA (United States)

    2017-07-15

    Pulmonary nodules are commonly encountered at staging CTs in patients with extrathoracic malignancies, but their significance on a per-patient basis remains uncertain. We undertook a retrospective analysis of pulmonary nodules identified in patients with a diagnosis of breast cancer from 2010 - 2015, evaluating nodules present at a baseline CT (i.e. prevalent nodules). We reviewed 211 patients with 248 individual nodules. The rate of malignancy in prevalent nodules is low, approximately 13 %. Variables associated with metastasis include pleural studding, hilar lymphadenopathy and the presence of extrapulmonary metastasis, as well as number of nodules, nodule size and nodule shape. Using a combination of these factors, we have developed an evidence-based multivariate decision tree to predict which nodules are malignant in these patients, which is 91 % accurate and 100 % sensitive for metastasis. We propose a simplified clinical prediction algorithm to guide radiologists and oncologists in managing patients with breast cancer and incidental pulmonary nodules. (orig.)

  13. Graphite nodule count and size distribution in thin-walled ductile cast iron

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2008-01-01

    Graphite nodule count and size distribution have been analysed in thin walled ductile cast iron. The 2D nodule counts have been converted into 3D nodule count by using Finite Difference Method (FDM). Particles having a diameter smaller than 5 µm should be neglected in the nodule count...... as these are inclusions and micro porosities that do not influence the solidification morphology. If there are many small graphite nodules as in thin walled castings only 3D nodule count calculated by FDM will give reliable results. 2D nodule count and 3D nodule count calculated by simple equations will give too low...... results. The 3D size distribution showed presence of primary graphite nodules in hypereutectic castings. In thin plates the nodule count is similar in eutectic and hypereutectic plates. In thicker plates the hypereutectic casting has the highest nodule count....

  14. Development of a clinical decision model for thyroid nodules

    Directory of Open Access Journals (Sweden)

    Eberhardt John

    2009-08-01

    Full Text Available Abstract Background Thyroid nodules represent a common problem brought to medical attention. Four to seven percent of the United States adult population (10–18 million people has a palpable thyroid nodule, however the majority (>95% of thyroid nodules are benign. While, fine needle aspiration remains the most cost effective and accurate diagnostic tool for thyroid nodules in current practice, over 20% of patients undergoing FNA of a thyroid nodule have indeterminate cytology (follicular neoplasm with associated malignancy risk prevalence of 20–30%. These patients require thyroid lobectomy/isthmusectomy purely for the purpose of attaining a definitive diagnosis. Given that the majority (70–80% of these patients have benign surgical pathology, thyroidectomy in these patients is conducted principally with diagnostic intent. Clinical models predictive of malignancy risk are needed to support treatment decisions in patients with thyroid nodules in order to reduce morbidity associated with unnecessary diagnostic surgery. Methods Data were analyzed from a completed prospective cohort trial conducted over a 4-year period involving 216 patients with thyroid nodules undergoing ultrasound (US, electrical impedance scanning (EIS and fine needle aspiration cytology (FNA prior to thyroidectomy. A Bayesian model was designed to predict malignancy in thyroid nodules based on multivariate dependence relationships between independent covariates. Ten-fold cross-validation was performed to estimate classifier error wherein the data set was randomized into ten separate and unique train and test sets consisting of a training set (90% of records and a test set (10% of records. A receiver-operating-characteristics (ROC curve of these predictions and area under the curve (AUC were calculated to determine model robustness for predicting malignancy in thyroid nodules. Results Thyroid nodule size, FNA cytology, US and EIS characteristics were highly predictive of

  15. Pulmonary nodules and metastases in colorectal cancer

    DEFF Research Database (Denmark)

    Nordholm-Carstensen, Andreas

    2016-01-01

    Patients with newly diagnosed colorectal cancer (CRC) are subjected to a preoperative thoraco-abdominal CT scan to determine the cancer stage. This staging is of relevance with regard to treatment and prognosis. About 20% of the patients have distant metastatic spread at the time of diagnosis, i...... is minimal. Furthermore, the current staging practice is complicated by a high number of incidental findings on the thoracic CT, so-called indeterminate pulmonary nodules (IPN). IPN can potentially represent SPCM. The purpose of this thesis was to estimate the prevalence, characteristics and clinical...... detected in 7.5% of the patients and in 37% of these cases the metastatic spread was confined to the lungs. The prevalence of SPCM increased with the implementation of thoracic CT in CRC staging. SPCM impaired survival significantly and was associated with increasing age and rectal cancer. Resection...

  16. Indeterminate Pulmonary Nodules in Colorectal-Cancer

    DEFF Research Database (Denmark)

    Nordholm-Carstensen, Andreas; Jorgensen, Lars N; Wille-Jørgensen, Peer A

    2015-01-01

    BACKGROUND: The clinical significance of indeterminate pulmonary nodules (IPN) at staging computed tomography (CT) for colorectal cancer (CRC), and the optimal diagnostic approach, are debated. This study aimed to analyse variability in radiologists' detection of IPN at staging CT for CRC. METHODS......: All patients with CRC referred to our center between 2006 and 2011 were included. Primary staging CT scans were re-evaluated by an experienced thoracic radiologist whose findings were entered into a dedicated database and merged with data from the Danish Colorectal Cancer Group database, the National...... investigated radiological characteristics or clinicopathological factors were significantly associated with malignancy of IPN. CONCLUSION: The characterization of pulmonary findings on staging CT for CRC varied greatly between the radiologists, and double-reading of scans with IPN is recommended prior...

  17. Thyroid nodule and the value of tumormarkers

    International Nuclear Information System (INIS)

    Goerges, R.; Bockisch, A.

    2008-01-01

    According to common scientific opinion thyroglobulin (hTg) is not recommended as a tumor marker for clarifying the dignity of thyroid nodules, due to a strong overlap between values of differentiated thyroid carcinoma (DTC) and benign thyroid nodules. Moreover, other benign thyroid diseases with cellular lesion, i.e. nodules and overt inflammation, lead to significantly increased thyroglobulin values (values in a four-digit range and even more in very rare cases). The determination of hTg before thyroid ablation can be a useful ''screening marker'' for patients with CUP-syndrome and suspicious thyroid lesions to identify subjects suffering under DTC. Furthermore, in the case of DTC preoperatively measured hTg will help to validate and evaluate hTg values in the follow-up of these patients. hTg determination can be disturbed by methodological artefacts, in particular by interfering anti-hTg auto-antibodies. For the authentication of hTg values anti-hTg auto-antibody measurement and/or recovery testing is therefore essential although both methods have advantages and disadvantages in that respect. Calcitonin (hCt) is a relatively reliable and specific marker for medullary thyroid carcinoma (MTC) or neoplastic C-cell hyperplasia provided that optimal techniques and appropriate interpretation of test results are applied. The use of two-site assays with a high specificity for the monomer molecule is advised, but false-positive values can still occur, i.e. in renal insufficiency, during therapy with proton pump inhibitors, in goiters with ''physiological'' C-cell hyperplasia and in autoimmune thyroiditis. The Thyroid Section of the German Society of Endocrinology recommends hCt-screening for patients with nodular goiter although some questions regarding epidemiology, health economy and methodology are not resolved yet. Basal hCT values exceeding 100 pg/ml are highly predictive for MTC after exclusion of the reasons mentioned above which can cause artificially increased

  18. Subcutaneous nodule: A case of Dirofilaria

    Science.gov (United States)

    D’Souza, Reshmina; Jakribettu, Ramakrishna Pai; Sudharsana, Sunil H; Aithala, Sathyamoorthy P

    2013-01-01

    Human subcutaneous dirofilariasis is a rare helminthic infection. It is caused by filarial worms of the Genus Dirofilaria, which is the natural parasites of dogs, cats, foxes, and wild mammals. Zoonotic filariasis caused by Dirofilaria species is rarely seen in the region of Dakshina Kannada. Most of them are seen in patients who are along the border of the district which shares its boundary with the state of Kerala, where dirofilariasis is constantly reported to occur. Here, we report a case of subcutaneous dirofilariasis, presenting as a subcutaneous nodule on the left cheek of a 28-year-old male from Cochin (Ernakulam), Kerala, South India. Two live worms were recovered from the subcutaneous nodular swelling. PMID:23776842

  19. Pulmonary nodules and metastases in colorectal cancer.

    Science.gov (United States)

    Nordholm-Carstensen, Andreas

    2016-01-01

    Patients with newly diagnosed colorectal cancer (CRC) are subjected to a preoperative thoraco-abdominal CT scan to determine the cancer stage. This staging is of relevance with regard to treatment and prognosis. About 20% of the patients have distant metastatic spread at the time of diagnosis, i.e. synchronous metastases. Most common are hepatic metastases followed by pulmonary involvement. The optimal staging modality for detecting synchronous pulmonary metastases is debated. It has been argued, that synchronous pulmonary metastases (SPCM) are rare in CRC and that the consequence of detecting SPCM is minimal. Furthermore, the current staging practice is complicated by a high number of incidental findings on the thoracic CT, so-called indeterminate pulmonary nodules (IPN). IPN can potentially represent SPCM. The purpose of this thesis was to estimate the prevalence, characteristics and clinical significance of IPN and SPCM detected at the primary staging in CRC. Study I was a systematic review of published studies on IPN in CRC focusing on the prevalence and radiological characteristics of IPN proving to be malignant. This knowledge would be of value in management strategies for IPN. On average 9% of all patients staged with a thoracic CT had IPN, however, the prevalence varied significantly between patients series. This was mainly attributed to varying/lacking definitions on IPN and variable radiological expertise in the assessment of the scans. Data were too inconsistently reported in the case series for a robust statement to be made on potential radiological characteristics suggestive of malignancy in IPN. Lymph node metastasis was the most common clinicopathological finding associated with malignancy of IPN. In conclusion, one patient of every 100 scanned patients had an IPN proving to a SPCM at follow-up, but we found no evidence that IPN should result in intensified diagnostic work-up besides routine follow-up for CRC. Study II was an analysis of the

  20. Pulmonary nodules: a quantitative method of diagnosis by evaluating nodule perimeter difference to approximate oval using three-dimensional CT images.

    Science.gov (United States)

    Kamiya, Hisashi; Murayama, Sadayuki; Kakinohana, Yasumasa; Miyara, Tetsuhiro

    2011-01-01

    The purpose of this study was to investigate whether maximum nodule perimeter to the approximate oval could discriminate benign nodules from malignancy. Measurement of maximum nodule perimeter difference to the approximate oval was performed using volume-rendering images of three directions of each pulmonary nodule. The margin was then traced manually and our custom software delineated the approximate oval automatically. The maximum nodule perimeter difference was 26.5±23.3 mm for malignant and 16.6±16.9 mm for benign nodules, showing an almost statistically significant difference (P=.07). This study suggests that the maximum nodule perimeter difference to the approximate oval of the malignant nodules has a tendency to be longer than benign nodules. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Root (Botany)

    Science.gov (United States)

    Robert R. Ziemer

    1981-01-01

    Plant roots can contribute significantly to the stability of steep slopes. They can anchor through the soil mass into fractures in bedrock, can cross zones of weakness to more stable soil, and can provide interlocking long fibrous binders within a weak soil mass. In deep soil, anchoring to bedrock becomes negligible, and lateral reinforcement predominates

  2. Co-inoculation of a Pea Core-Collection with Diverse Rhizobial Strains Shows Competitiveness for Nodulation and Efficiency of Nitrogen Fixation Are Distinct traits in the Interaction.

    Science.gov (United States)

    Bourion, Virginie; Heulin-Gotty, Karine; Aubert, Véronique; Tisseyre, Pierre; Chabert-Martinello, Marianne; Pervent, Marjorie; Delaitre, Catherine; Vile, Denis; Siol, Mathieu; Duc, Gérard; Brunel, Brigitte; Burstin, Judith; Lepetit, Marc

    2017-01-01

    Pea forms symbiotic nodules with Rhizobium leguminosarum sv. viciae (Rlv). In the field, pea roots can be exposed to multiple compatible Rlv strains. Little is known about the mechanisms underlying the competitiveness for nodulation of Rlv strains and the ability of pea to choose between diverse compatible Rlv strains. The variability of pea-Rlv partner choice was investigated by co-inoculation with a mixture of five diverse Rlv strains of a 104-pea collection representative of the variability encountered in the genus Pisum . The nitrogen fixation efficiency conferred by each strain was determined in additional mono-inoculation experiments on a subset of 18 pea lines displaying contrasted Rlv choice. Differences in Rlv choice were observed within the pea collection according to their genetic or geographical diversities. The competitiveness for nodulation of a given pea-Rlv association evaluated in the multi-inoculated experiment was poorly correlated with its nitrogen fixation efficiency determined in mono-inoculation. Both plant and bacterial genetic determinants contribute to pea-Rlv partner choice. No evidence was found for co-selection of competitiveness for nodulation and nitrogen fixation efficiency. Plant and inoculant for an improved symbiotic association in the field must be selected not only on nitrogen fixation efficiency but also for competitiveness for nodulation.

  3. Automated Root Tracking with "Root System Analyzer"

    Science.gov (United States)

    Schnepf, Andrea; Jin, Meina; Ockert, Charlotte; Bol, Roland; Leitner, Daniel

    2015-04-01

    Crucial factors for plant development are water and nutrient availability in soils. Thus, root architecture is a main aspect of plant productivity and needs to be accurately considered when describing root processes. Images of root architecture contain a huge amount of information, and image analysis helps to recover parameters describing certain root architectural and morphological traits. The majority of imaging systems for root systems are designed for two-dimensional images, such as RootReader2, GiA Roots, SmartRoot, EZ-Rhizo, and Growscreen, but most of them are semi-automated and involve mouse-clicks in each root by the user. "Root System Analyzer" is a new, fully automated approach for recovering root architectural parameters from two-dimensional images of root systems. Individual roots can still be corrected manually in a user interface if required. The algorithm starts with a sequence of segmented two-dimensional images showing the dynamic development of a root system. For each image, morphological operators are used for skeletonization. Based on this, a graph representation of the root system is created. A dynamic root architecture model helps to determine which edges of the graph belong to an individual root. The algorithm elongates each root at the root tip and simulates growth confined within the already existing graph representation. The increment of root elongation is calculated assuming constant growth. For each root, the algorithm finds all possible paths and elongates the root in the direction of the optimal path. In this way, each edge of the graph is assigned to one or more coherent roots. Image sequences of root systems are handled in such a way that the previous image is used as a starting point for the current image. The algorithm is implemented in a set of Matlab m-files. Output of Root System Analyzer is a data structure that includes for each root an identification number, the branching order, the time of emergence, the parent

  4. Pulmonary nodule characterization, including computer analysis and quantitative features.

    Science.gov (United States)

    Bartholmai, Brian J; Koo, Chi Wan; Johnson, Geoffrey B; White, Darin B; Raghunath, Sushravya M; Rajagopalan, Srinivasan; Moynagh, Michael R; Lindell, Rebecca M; Hartman, Thomas E

    2015-03-01

    Pulmonary nodules are commonly detected in computed tomography (CT) chest screening of a high-risk population. The specific visual or quantitative features on CT or other modalities can be used to characterize the likelihood that a nodule is benign or malignant. Visual features on CT such as size, attenuation, location, morphology, edge characteristics, and other distinctive "signs" can be highly suggestive of a specific diagnosis and, in general, be used to determine the probability that a specific nodule is benign or malignant. Change in size, attenuation, and morphology on serial follow-up CT, or features on other modalities such as nuclear medicine studies or MRI, can also contribute to the characterization of lung nodules. Imaging analytics can objectively and reproducibly quantify nodule features on CT, nuclear medicine, and magnetic resonance imaging. Some quantitative techniques show great promise in helping to differentiate benign from malignant lesions or to stratify the risk of aggressive versus indolent neoplasm. In this article, we (1) summarize the visual characteristics, descriptors, and signs that may be helpful in management of nodules identified on screening CT, (2) discuss current quantitative and multimodality techniques that aid in the differentiation of nodules, and (3) highlight the power, pitfalls, and limitations of these various techniques.

  5. Frequency of Thyroid Nodules among Patients with Colonic Polyps

    Directory of Open Access Journals (Sweden)

    Cevdet Duran

    2012-01-01

    Full Text Available Aim. Colonic polyps and thyroid nodules are common diseases and their frequency increases with age. In the literature, there is no study investigating the coexistence of colonic polyps and thyroid nodules. Therefore, this study was designed to investigate thyroid nodule prevalence in patients with colonic polyps. Material and Methods. Sixty-six patients with colonic polyps and 146 patients without colonic polyps enrolled into the study. Age and sex matched control group was composed from patients without colonic polyps. Colonoscopic examinations, thyroid ultrasonographies were performed in all patients, and TSH were measured. Results. Male/female ratio in polyp and control groups were 40/26 versus 68/78, respectively (P=0.058. Mean ages were similar in both groups (53.3±11.4 versus, 51.8±11.4, P=0.373. Thyroid nodule was detected in 44 (66.7% patients with polyps and in 61 (41.8% controls (P=0.001. Patients with adenomatous polyps had 5 or more thyroid nodules compared to patients with hyperplastic polyps (P=0.03. Thyroid nodules were more prevalent among patients aged 50 or older compared to 50 years or less (P=0.023. Conclusion. Thyroid nodules were detected more common in patients with colonic polyps. Further studies are needed to clarify this coexistence.

  6. Metabolomic Analysis of Alfalfa (Medicago sativa L. Root-Symbiotic Rhizobia Responses under Alkali Stress

    Directory of Open Access Journals (Sweden)

    Tingting Song

    2017-07-01

    Full Text Available Alkaline salts (e.g., NaHCO3 and Na2CO3 causes more severe morphological and physiological damage to plants than neutral salts (e.g., NaCl and Na2SO4 due to differences in pH. The mechanism by which plants respond to alkali stress is not fully understood, especially in plants having symbotic relationships such as alfalfa (Medicago sativa L.. Therefore, a study was designed to evaluate the metabolic response of the root-nodule symbiosis in alfalfa under alkali stress using comparative metabolomics. Rhizobium-nodulized (RI group and non-nodulized (NI group alfalfa roots were treated with 200 mmol/L NaHCO3 and, roots samples were analyzed for malondialdehydyde (MDA, proline, glutathione (GSH, superoxide dismutase (SOD, and peroxidase (POD content. Additionally, metabolite profiling was conducted using gas chromatography combined with time-of-flight mass spectrometry (GC/TOF-MS. Phenotypically, the RI alfalfa exhibited a greater resistance to alkali stress than the NI plants examined. Physiological analysis and metabolic profiling revealed that RI plants accumulated more antioxidants (SOD, POD, GSH, osmolytes (sugar, glycols, proline, organic acids (succinic acid, fumaric acid, and alpha-ketoglutaric acid, and metabolites that are involved in nitrogen fixation. Our pairwise metabolomics comparisons revealed that RI alfalfa plants exhibited a distinct metabolic profile associated with alkali putative tolerance relative to NI alfalfa plants. Data provide new information about the relationship between non-nodulized, rhizobium-nodulized alfalfa and alkali resistance.

  7. Metabolomic Analysis of Alfalfa (Medicago sativa L.) Root-Symbiotic Rhizobia Responses under Alkali Stress.

    Science.gov (United States)

    Song, Tingting; Xu, Huihui; Sun, Na; Jiang, Liu; Tian, Pu; Yong, Yueyuan; Yang, Weiwei; Cai, Hua; Cui, Guowen

    2017-01-01

    Alkaline salts (e.g., NaHCO 3 and Na 2 CO 3 ) causes more severe morphological and physiological damage to plants than neutral salts (e.g., NaCl and Na 2 SO 4 ) due to differences in pH. The mechanism by which plants respond to alkali stress is not fully understood, especially in plants having symbotic relationships such as alfalfa ( Medicago sativa L.). Therefore, a study was designed to evaluate the metabolic response of the root-nodule symbiosis in alfalfa under alkali stress using comparative metabolomics. Rhizobium-nodulized (RI group) and non-nodulized (NI group) alfalfa roots were treated with 200 mmol/L NaHCO 3 and, roots samples were analyzed for malondialdehydyde (MDA), proline, glutathione (GSH), superoxide dismutase (SOD), and peroxidase (POD) content. Additionally, metabolite profiling was conducted using gas chromatography combined with time-of-flight mass spectrometry (GC/TOF-MS). Phenotypically, the RI alfalfa exhibited a greater resistance to alkali stress than the NI plants examined. Physiological analysis and metabolic profiling revealed that RI plants accumulated more antioxidants (SOD, POD, GSH), osmolytes (sugar, glycols, proline), organic acids (succinic acid, fumaric acid, and alpha-ketoglutaric acid), and metabolites that are involved in nitrogen fixation. Our pairwise metabolomics comparisons revealed that RI alfalfa plants exhibited a distinct metabolic profile associated with alkali putative tolerance relative to NI alfalfa plants. Data provide new information about the relationship between non-nodulized, rhizobium-nodulized alfalfa and alkali resistance.

  8. Danish Rhizobium leguminosarum strains nodulating ‘Afghanistan’ pea (Pisum sativum)

    DEFF Research Database (Denmark)

    Jensen, Erik Steen; Sørensen, Lasse Holst; Engvild, Kjeld Christensen

    1986-01-01

    A wild pea (Pisum sativum L.) native to Afghanistan normally known to be resisant to nodulation with European strains of Rhizobium leguminosarum was nodulated early and effectively in field soil in Denmark. Isolates from nodules formed effective nodules abundantly on 'Afghanistan' on reinfection...... pattern with Rhizobium leguminosarum strains isolated from a modern pea variety cultivated in the same field....

  9. Genetic variation in nodule size at different sites on the skins of ...

    African Journals Online (AJOL)

    Apart from the limitations evident from these results, the objective measurement of nodules on ostrich skins is tedious when done manually, with little prospect for automation. The number of nodules per dm² (nodule density) was considered within skin sites as an indirect criterion for the improvement of nodule size. However ...

  10. Root disease management guidebook

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    Forest tree root pathogens are widespread throughout all forested ecosystems in British Columbia. This guidebook provides a background to forest root disease management (including why, where, and how to manage root disease) and describes the necessary tools for managing root disease. It includes a review of the distribution of major root diseases in the province, host susceptibility and symptomology, and root disease and stand dynamics. The tools described include disease hazard and risk assessment, stratification surveys, and treatment methods. The major root diseases covered in the guide are Armillaria root disease, laminated root rot, Tomentosus root rot, blackstain root disease, and Annosus root disease.

  11. Persistent pulmonary subsolid nodules: model-based iterative reconstruction for nodule classification and measurement variability on low-dose CT.

    Science.gov (United States)

    Kim, Hyungjin; Park, Chang Min; Kim, Seong Ho; Lee, Sang Min; Park, Sang Joon; Lee, Kyung Hee; Goo, Jin Mo

    2014-11-01

    To compare the pulmonary subsolid nodule (SSN) classification agreement and measurement variability between filtered back projection (FBP) and model-based iterative reconstruction (MBIR). Low-dose CTs were reconstructed using FBP and MBIR for 47 patients with 47 SSNs. Two readers independently classified SSNs into pure or part-solid ground-glass nodules, and measured the size of the whole nodule and solid portion twice on both reconstruction algorithms. Nodule classification agreement was analyzed using Cohen's kappa and compared between reconstruction algorithms using McNemar's test. Measurement variability was investigated using Bland-Altman analysis and compared with the paired t-test. Cohen's kappa for inter-reader SSN classification agreement was 0.541-0.662 on FBP and 0.778-0.866 on MBIR. Between the two readers, nodule classification was consistent in 79.8 % (75/94) with FBP and 91.5 % (86/94) with MBIR (p = 0.027). Inter-reader measurement variability range was -5.0-2.1 mm on FBP and -3.3-1.8 mm on MBIR for whole nodule size, and was -6.5-0.9 mm on FBP and -5.5-1.5 mm on MBIR for solid portion size. Inter-reader measurement differences were significantly smaller on MBIR (p = 0.027, whole nodule; p = 0.011, solid portion). MBIR significantly improved SSN classification agreement and reduced measurement variability of both whole nodules and solid portions between readers. • Low-dose CT using MBIR algorithm improves reproducibility in the classification of SSNs. • MBIR would enable more confident clinical planning according to the SSN type. • Reduced measurement variability on MBIR allows earlier detection of potentially malignant nodules.

  12. India's manganese nodule mine site in the Central Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Banakar, V.K.

    This commentary highlights the activities of massive exploration programme for manganese nodule deposits in the Central Indian Basin located 5 km below the ocean surface and India's claim for mine site development and registration with UNCLOS...

  13. Ferromanganese nodules from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Jauhari, P.; Pattan, J.N.

    In order to delineate a mine site for ferromanganese nodules, extensive surveys were conducted in Central Indian Ocean Basin. Mapping of the basin by multibeam swath bathymetry (Hydrosweep) has revealed many new bottom relief features...

  14. Buried nodules and associated sediments from the central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Banerjee, R; Iyer, S.D.; Dutta, P.

    Buried nodules from siliceous sediments in the central Indian Basin are morphologically variable and mineralogically consist of d-MnO2 incipient todorokite. Compositionally they are weakly diagenetic. The sediment coarse fractions ( 63 mu m...

  15. The Indian Ocean nodule field: Geology and resource potential

    Digital Repository Service at National Institute of Oceanography (India)

    Mukhopadhyay, R.; Ghosh, A.K.; Iyer, S.D.

    This book briefly accounts for the physiography, geology, biology, physics and chemistry of the nodule field, and discusses in detail the aspects of structure, tectonic and volcanism in the field. The role of the ocean floor sediment that hosts...

  16. Manganese nodules in the Exclusive Economic Zone of Mauritius

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.; ShyamPrasad, M.

    The distribution of manganese nodules in the Exclusive Economic Zone of the island nation Mauritius was delineated during cruise SK-35 of ORV Sagar Kanya in 1987. The areas surveyed included Saya de Malha and Nazareth Banks, the Cargados Carajos...

  17. Manganese nodules as a possible source of precious metals

    Digital Repository Service at National Institute of Oceanography (India)

    Banerjee, R.

    100 times more Pt. Thus the manganese nodules resources at Central Indian Basin, could be a potential source for precious metals including Pt, Palladium (Pd) and Silver (Ag). In this article the possible precious metal resources present in the Central...

  18. Radiographic test phantom for computed tomographic lung nodule analysis

    International Nuclear Information System (INIS)

    Zerhouni, E.A.

    1987-01-01

    This patent describes a method for evaluating a computed tomograph scan of a nodule in a lung of a human or non-human animal. The method comprises generating a computer tomograph of a transverse section of the animal containing lung and nodule tissue, and generating a second computer tomograph of a test phantom comprising a device which simulates the transverse section of the animal. The tissue simulating portions of the device are constructed of materials having radiographic densities substantially identical to those of the corresponding tissue in the simulated transverse section of the animal and have voids therein which simulate, in size and shape, the lung cavities in the transverse section and which contain a test reference nodule constructed of a material of predetermined radiographic density which simulates in size, shape and position within a lung cavity void of the test phantom the nodule in the transverse section of the animal and comparing the respective tomographs

  19. Scripps Institution of Oceanography Ferromanganese Nodule Analysis File - IDOE Portion

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Scripps Institution of Oceanography (SIO) compiled data on the geochemistry of marine ferromanganese nodules, funded by the U.S. National Science Foundation...

  20. Pulmonary Nodules with Cutaneous Manifestations: A Case Report and Discussion

    Directory of Open Access Journals (Sweden)

    Ardiles T

    2012-04-01

    Full Text Available The differential diagnosis of multiple pulmonary nodules is large and includes congenital and inherited disorders, malignancy, infectious etiologies, noninfectious granulomatous and inflammatory conditions,among many others. Diagnostic evaluation is aided by attention to extrapulmonary symptoms and features. We herein describe an unusual case of multiple pulmonary nodules attributed to cysticercosis and present a discussion of pathophysiologic changes related to medications and highlight the diagnostic value of extrapulmonary cutaneous features.

  1. Pulmonary necrobiotic nodules: a rare extraintestinal manifestation of Crohn's disease

    Directory of Open Access Journals (Sweden)

    G. Warwick

    2009-03-01

    Full Text Available The present article reports the case of a 22-yr-old female with new onset Crohn's colitis, anterior uveitis and multiple pulmonary nodules which, on histological examination, were necrobiotic nodules. This is a rare but recognised pulmonary extraintestinal manifestation of Crohn's disease and only the fourth reported case. The present case report is followed by a brief review of the relevant literature.

  2. Rhizobium sp. IRBG74 Alters Arabidopsis Root Development by Affecting Auxin Signaling

    Science.gov (United States)

    Zhao, Catherine Z.; Huang, Jian; Gyaneshwar, Prasad; Zhao, Dazhong

    2018-01-01

    Rhizobium sp. IRBG74 not only nodulates Sesbania cannabina but also can enhance rice growth; however, the underlying molecular mechanisms are not clear. Here, we show that Rhizobium sp. IRBG74 colonizes the roots of Arabidopsis thaliana, which leads to inhibition in the growth of main root but enhancement in the formation of lateral roots. The promotion of lateral root formation by Rhizobium sp. IRBG74 in the fls2-1 mutant, which is insensitive to flagellin, is similar to the wild-type plant, while the auxin response deficient mutant tir1-1 is significantly less sensitive to Rhizobium sp. IRBG74 than the wild type in terms of the inhibition of main root elongation and the promotion of lateral root formation. Further transcriptome analysis of Arabidopsis roots inoculated with Rhizobium sp. IRBG74 revealed differential expression of 50 and 211 genes at 24 and 48 h, respectively, and a majority of these genes are involved in auxin signaling. Consistent with the transcriptome analysis results, Rhizobium sp. IRBG74 treatment induces expression of the auxin responsive reporter DR5:GUS in roots. Our results suggest that in Arabidopsis Rhizobium sp. IRBG74 colonizes roots and promotes the lateral root formation likely through modulating auxin signaling. Our work provides insight into the molecular mechanisms of interactions between legume-nodulating rhizobia and non-legume plants. PMID:29354099

  3. Relationship between size and geochemistry of polymetallic nodules from the Central Indian Ocean Basin: Significance in selection of high grade nodules

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.; Ambre, N.V.

    Morphological, mineralogical and geochemical studies on nodules of different sizes collected from the Central Indian Ocean Basin (CIOB) show two suits of nodule formation by oxic diagenetic and hydrogenous process resulting into distinct properties...

  4. Locally Finite Root Supersystems

    OpenAIRE

    Yousofzadeh, Malihe

    2013-01-01

    We introduce the notion of locally finite root supersystems as a generalization of both locally finite root systems and generalized root systems. We classify irreducible locally finite root supersystems.

  5. Auto Diagnostics of Lung Nodules Using Minimal Characteristics Extraction Technique

    Directory of Open Access Journals (Sweden)

    Diego M. Peña

    2016-03-01

    Full Text Available Computer-aided detection (CAD systems provide useful tools and an advantageous process to physicians aiming to detect lung nodules. This paper develops a method composed of four processes for lung nodule detection. The first step employs image acquisition and pre-processing techniques to isolate the lungs from the rest of the body. The second stage involves the segmentation process using a 2D algorithm to affect every layer of a scan eliminating non-informative structures inside the lungs, and a 3D blob algorithm associated with a connectivity algorithm to select possible nodule shape candidates. The combinations of these algorithms efficiently eliminate the high rates of false positives. The third process extracts eight minimal representative characteristics of the possible candidates. The final step utilizes a support vector machine for classifying the possible candidates into nodules and non-nodules depending on their features. As the objective is to find nodules bigger than 4mm, the proposed approach demonstrated quite encouraging results. Among 65 computer tomography (CT scans, 94.23% of sensitivity and 84.75% in specificity were obtained. The accuracy of these two results was 89.19% taking into consideration that 45 scans were used for testing and 20 for training. The rate of false positives was 0.2 per scan.

  6. Usefulness of semiquantitative elastography in predicting malignancy in thyroid nodules.

    Science.gov (United States)

    Franco Uliaque, C; Pardo Berdún, F J; Laborda Herrero, R; Pérez Lórenz, C

    2016-01-01

    To retrospectively review the diagnostic capacity of semiquantitative elastography in differentiating between benign and malignant thyroid nodules. We analyzed 314 thyroid nodules in 295 consecutive patients referred to the endocrinology department for cytological study, studying all by conventional ultrasonography, elastography, and fine-needle aspiration cytology (FNAC). Using a semiquantitative elastography system that portrays tissue stiffness through a color map, we designed our own classification system for thyroid nodules based on their characteristics on elastography. We classified nodules into three groups: predominantly soft, predominantly stiff, and mosaic patterned. We used logistic regression analysis to investigate the relation between elastography and thyroid cancer. We obtained a definite diagnosis of malignancy after surgery in 19 nodules, of which on elastography 8 had the mosaic pattern, 6 were predominantly stiff, and 5 were predominantly soft. We found no significant association between the pattern on elastography and the probability of malignancy in any of the models. According to our study, la probability of malignancy in a thyroid nodule is not related to the findings at elastography. Therefore, semiquantitative elastography as used in this study cannot obviate FNAC. Copyright © 2016 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Overview and strategic management of subsolid pulmonary nodules.

    Science.gov (United States)

    Godoy, Myrna C B; Naidich, David P

    2012-07-01

    A new classification of lung adenocarcinoma has been proposed recently-the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification. Abundant information from recent lung cancer computed tomography (CT) screening programs has increased our understanding of the strong, although imperfect, correlation between histologic findings of lung adenocarcinoma and subsolid pulmonary nodules on CT, including both "pure" ground-glass nodules (GGNs) and "part-solid" GGNs. Moreover, serial CT imaging has demonstrated stepwise progression of these nodules in a subset of patients, characterized by increase in size and density of GGNs and development of a solid component. Given the higher incidence of malignancy and the considerably lower growth rate of subsolid nodules, dedicated standardized guidelines for management of these nodules have been proposed, including long-term (≥3 y) CT follow-up using a low-dose technique. Radiologists should be familiar with the new terminology of lung adenocarcinomas and strategic management of subsolid pulmonary nodules.

  8. On the computed tomographic diagnosis of pulmonary nodules

    International Nuclear Information System (INIS)

    Higashi, Yuuichirou

    1988-01-01

    Computed tomography (CT) was used to examine 53 pulmonary nodules which were considered not definitely calcified on plain radiographs or conventional tomograms. An average CT number was calculate for each lesion. For the primary lung cancers, the average CT number was 36 HU with a standard deviation of 6.6 HU, while the benign lesions had the mean CT number of 69 HU, with a standard deviation of 42.8 HU. The mean CT number separating lung malignancies from benign lesions was 78.8 HU. To evaluate the attenuation values within each nodule, iso-CT value map was obtained by using Siemens therapy planning system, MEVAPLAN. Nodules were classified into five categories, Type I to V. All of three nodules classified as Type IV were benign. Iso-CT value map was effective in establishing the benignancy of nodules. The quantitative computed tomographic analysis of pulmonary nodules was evaluated by dual-energy CT. Dual-energy CT has the potential to eliminate the effect of spectral hardening by use of monoenergic images derived from dual-kV data and to separate high CT numbers due to calcium from those due to high density organic material. (author)

  9. Nodulation and N2 fixation effectiveness of Bradyrhizobium strains in symbiosis with Adzuki Bean, Vigna angularis

    Directory of Open Access Journals (Sweden)

    Dušica Delić

    2010-04-01

    Full Text Available In pot experiment, one isolate Knj from a Serbian soil, four strains of Bradyrhizobium japonicum and three strains of Bradyrhizobium spp. were examined for the effect on adzuki bean nodulation and effectiveness in symbiotic N2 fixation. All the tested strains produced root nodules in adzuki bean. Strains of B. japonicum showed high potential of N2 fixation, particularly 525 and 542. B. japonicum strains resulted 65-71% shoot dry weight and 99-138% total N content of uninoculated control with full N content (100%. No significant difference was found between the plants inoculated with Bradyrhizobium spp. strains and uninoculated control plants without N (40-42 and 42% shoot dry weight, respectively, which indicated symbiotic N2 fixation inactivity of the Bradyrhizobium spp. strains. Knj strain had the middle position (56% shoot dry weight. These data showed that B. japonicum 525 and 542 strains could be used in further investigations in order to apply them as inoculants in microbiological N fertilizers.

  10. Rhizobium helanshanense sp. nov., a bacterium that nodulates Sphaerophysa salsula (Pall.) DC. in China.

    Science.gov (United States)

    Qin, Wei; Deng, Zhen Shan; Xu, Lin; Wang, Na Na; Wei, Ge Hong

    2012-05-01

    Studying rhizobia in the root nodules of Sphaerophysa salsula (Pall.) DC in the northwest of China, we obtained five strains classified as genus Rhizobium on the basis of their 16S rRNA gene sequences. The sequence similarity of strain CCNWQTX14(T) with the most related species was 99.0%. Further phylogenetic analysis of housekeeping genes (recA and atpD) suggested the five strains comprised a novel lineage within Rhizobium. The nifH and nodD gene sequences of CCNWQTX14(T) were phylogenetically closely related with those of Sinorhizobium kummerowiae and R. sphaerophysae, respectively. The five strains isolated from different places were also distinct from related Rhizobium species using ERIC fingerprint profiles. The DNA-DNA hybridization value was 41.8% between CCNWQTX14(T) and Rhizobium sphaerophysae CCNWGS0238(T). Our novel strains were only able to form effective nodules on its original host Sphaerophysa salsula. Our data showed that the five Rhizobium strains formed a unique genomic species, for which a novel species Rhizobium helanshanense sp. nov. is proposed. The type strain is CCNWQTX14(T) (=ACCC 16237(T) =HAMBI 3083(T)).

  11. Rhizobium vallis sp. nov., isolated from nodules of three leguminous species.

    Science.gov (United States)

    Wang, Fang; Wang, En Tao; Wu, Li Juan; Sui, Xin Hua; Li, Ying; Chen, Wen Xin

    2011-11-01

    Four bacterial strains isolated from root nodules of Phaseolus vulgaris, Mimosa pudica and Indigofera spicata plants grown in the Yunnan province of China were identified as a lineage within the genus Rhizobium according to the analysis of 16S rRNA gene sequences, sharing most similarity with Rhizobium lusitanum P1-7(T) (99.1 % sequence similarity) and Rhizobium rhizogenes IAM 13570(T) (99.0 %). These strains also formed a distinctive group from the reference strains for defined species of the genus Rhizobium in a polyphasic approach, including the phylogenetic analyses of the 16S rRNA gene and housekeeping genes (recA, atpD, glnII), DNA-DNA hybridization, BOX-PCR fingerprinting, phenotypic characterization, SDS-PAGE of whole-cell proteins, and cellular fatty acid profiles. All the data obtained in this study suggested that these strains represent a novel species of the genus Rhizobium, for which the name Rhizobium vallis sp. nov. is proposed. The DNA G+C content (mol%) of this species varied between 60.9 and 61.2 (T(m)). The type strain of R. vallis sp. nov. is CCBAU 65647(T) ( = LMG 25295(T) =HAMBI 3073(T)), which has a DNA G+C content of 60.9 mol% and forms effective nodules on Phaseolus vulgaris.

  12. [Factor analysis of interactions between alfalfa nodule bacteria (Sinorhizobium meliloti) genes that regulate symbiotic nitrogen fixation].

    Science.gov (United States)

    Provorov, N A; Chuklina, E; Vorob'ev, N I; Onishchuk, O P; Simarov, B V

    2013-04-01

    Factor analysis has been conducted for the data on the interaction between the genes of the root nodule bacteria (rhizobia), which influence the efficiency of symbiosis with leguminous plants, including dctA (encoding succinate permease), dctBD (activating the dctA gene due to binding its enhancer in the presence of succinate), rpoN (activating the promoters of dctA and nitrogenase genes nifHDK), and nifA (activating the nitrogenase genes due to binding their enhancers). The analysis of the alfalfa rhizobia (Sinorhizobium meliloti) recombinants that contain additional copies ofthese genes suggested the antagonistic (epistatic) interaction between nifA and rpoN. It may be associated either with the competition for C compounds imported into the nodules between the energy production and nitrogen assimilation processes or with the competition for redox potentials between the oxidative phosphorylation and nitrogen fixation processes. Since the phenotypic effects of the studied genes depend on the activity of nitrogen export into the aerial parts of plants, we suppose that its accumulation in bacteroids impairs the activation of the nifHDK genes by the NifA protein due to its interaction with the GlnB protein (the nitrogen metabolism regulator) or with the FixLJ and ActSR proteins (the redox potential regulators).

  13. Persistent pulmonary subsolid nodules: model-based iterative reconstruction for nodule classification and measurement variability on low-dose CT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyungjin; Kim, Seong Ho; Lee, Sang Min; Lee, Kyung Hee [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Park, Chang Min; Park, Sang Joon; Goo, Jin Mo [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University, Cancer Research Institute, Seoul (Korea, Republic of)

    2014-11-15

    To compare the pulmonary subsolid nodule (SSN) classification agreement and measurement variability between filtered back projection (FBP) and model-based iterative reconstruction (MBIR). Low-dose CTs were reconstructed using FBP and MBIR for 47 patients with 47 SSNs. Two readers independently classified SSNs into pure or part-solid ground-glass nodules, and measured the size of the whole nodule and solid portion twice on both reconstruction algorithms. Nodule classification agreement was analyzed using Cohen's kappa and compared between reconstruction algorithms using McNemar's test. Measurement variability was investigated using Bland-Altman analysis and compared with the paired t-test. Cohen's kappa for inter-reader SSN classification agreement was 0.541-0.662 on FBP and 0.778-0.866 on MBIR. Between the two readers, nodule classification was consistent in 79.8 % (75/94) with FBP and 91.5 % (86/94) with MBIR (p = 0.027). Inter-reader measurement variability range was -5.0-2.1 mm on FBP and -3.3-1.8 mm on MBIR for whole nodule size, and was -6.5-0.9 mm on FBP and -5.5-1.5 mm on MBIR for solid portion size. Inter-reader measurement differences were significantly smaller on MBIR (p = 0.027, whole nodule; p = 0.011, solid portion). MBIR significantly improved SSN classification agreement and reduced measurement variability of both whole nodules and solid portions between readers. (orig.)

  14. Nodulation control of crack fertilization technique reduced the growth inhibition of soybean caused by short-term waterlogging at early vegetative stage

    Directory of Open Access Journals (Sweden)

    Koji Yamane

    2016-07-01

    Full Text Available Waterlogging is the constraint for soybean growth and yield, because soybean is often cultivated in upland fields converted from paddy in Japan. However, efficient cultivation techniques for alleviating the adverse effects have not been developed. We have proposed the new soybean cultivation technique named crack fertilization which enables yield increase due to enhancing new root growth and N acquisition by increasing nodulation. Waterlogging induces N deficiency due to the suppression of nutrient uptake by the inhibition of root growth and nodule activity. Thus, it is hypothesized that crack fertilization would be effective to alleviate the inhibition of soybean growth and yield. The soybean cultivar of Sachiyutaka was planted in 1/5000 a Wagner pots and root boxes. Two separate waterlogging treatments were imposed to soybean plants at different growth stages, V1 and R4, and crack fertilization was done at V3. After these treatments, soybean plants were sampled at R5 in 2012 and 2013 experiments, respectively. Waterlogging at V1 and R4 inhibited the growth and yield of soybean and nodule growth, and the decreases in physiological parameters of soybean such as photosynthesis, chlorophyll content, and xylem sap exudation rate were observed. The adverse effects of waterlogging at V1 were alleviated by crack fertilization at V3, whereas crack fertilization could not alleviate the adverse effects of waterlogging at R4. Thus, crack fertilization after waterlogging at early vegetative stage would be the cultivation technique that enables to alleviate the adverse effects.

  15. Competitive nodulation blocking of cv. Afghanistan pea is related to high levels of nodulation factors made by some strains of Rhizobium leguminosarum bv. viciae

    NARCIS (Netherlands)

    Hogg, B.; Davies, A.E.; Wilson, K.E.; Bisseling, T.; Downie, J.A.

    2002-01-01

    Cultivar Afghanistan peas are resistant to nodulation by many strains of Rhizobium leguminosarum bv. viciae but are nodulated by strain TOM, which carries the host specificity gene nodX. Some strains that lack nodX can inhibit nodulation of cv. Afghanistan by strain TOM. We present evidence that

  16. Genome sequence of the South American clover-nodulating Rhizobium leguminosarum bv. trifolii strain WSM597

    Science.gov (United States)

    Reeve, Wayne; Terpolilli, Jason; Melino, Vanessa; Ardley, Julie; Tian, Rui; De Meyer, Sofie; Tiwari, Ravi; Yates, Ronald; O’Hara, Graham; Howieson, John; Ninawi, Mohamed; Held, Brittany; Bruce, David; Detter, Chris; Tapia, Roxanne; Han, Cliff; Wei, Chia-Lin; Huntemann, Marcel; Han, James; Chen, I-Min; Mavromatis, Konstantinos; Markowitz, Victor; Ivanova, Natalia; Ovchinnikova, Galina; Pagani, Ioanna; Pati, Amrita; Goodwin, Lynne; Woyke, Tanja; Kyrpides, Nikos

    2013-01-01

    Rhizobium leguminosarum bv. trifolii strain WSM597 is an aerobic, motile, Gram-negative, non-spore-forming rod isolated from a root nodule of the annual clover Trifolium pallidum L. growing at Glencoe Research Station near Tacuarembó, Uruguay. This strain is generally ineffective for nitrogen (N2) fixation with clovers of Mediterranean, North American and African origin, but is effective on the South American perennial clover T. polymorphum Poir. Here we describe the features of R. leguminosarum bv. trifolii strain WSM597, together with genome sequence information and annotation. The 7,634,384 bp high-quality-draft genome is arranged in 2 scaffolds of 53 contigs, contains 7,394 protein-coding genes and 87 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program. PMID:24976883

  17. Bradyrhizobium manausense sp. nov., isolated from effective nodules of Vigna unguiculata grown in Brazilian Amazonian rainforest soils.

    Science.gov (United States)

    Silva, Flavia V; De Meyer, Sofie E; Simões-Araújo, Jean L; Barbé, Tatiane da Costa; Xavier, Gustavo R; O'Hara, Graham; Ardley, Julie K; Rumjanek, Norma G; Willems, Anne; Zilli, Jerri E

    2014-07-01

    Root nodule bacteria were trapped within cowpea (Vigna unguiculata) in soils with different cultivation histories collected from the Amazonian rainforest in northern Brazil. Analysis of the 16S rRNA gene sequences of six strains (BR 3351(T), BR 3307, BR 3310, BR 3315, BR 3323 BR and BR 3361) isolated from cowpea nodules showed that they formed a distinct group within the genus Bradyrhizobium, which was separate from previously identified type strains. Phylogenetic analyses of three housekeeping genes (glnII, recA and rpoB) revealed that Bradyrhizobium huanghuaihaiense CCBAU 23303(T) was the most closely related type strain (96% sequence similarity or lower). Chemotaxonomic data, including fatty acid profiles (predominant fatty acids being C16 : 0 and summed feature 8), the slow growth rate and carbon compound utilization patterns supported the assignment of the strains to the genus Bradyrhizobium. The results of DNA-DNA hybridizations, antibiotic resistance and physiological tests differentiated these novel strains from the most closely related species of the genus Bradyrhizobium with validly published names. Symbiosis-related genes for nodulation (nodC) and nitrogen fixation (nifH) grouped the novel strains of the genus Bradyrhizobium together with Bradyrhizobium iriomotense strain EK05(T), with 94% and 96% sequence similarity, respectively. Based on these data, these six strains represent a novel species for which the name Brabyrhizobium manausense sp. nov. (BR 3351(T) = HAMBI 3596(T)), is proposed. © 2014 IUMS.

  18. Leguminous plants nodulated by selected strains of Cupriavidus necator grow in heavy metal contaminated soils amended with calcium silicate.

    Science.gov (United States)

    Avelar Ferreira, Paulo Ademar; Lopes, Guilherme; Bomfeti, Cleide Aparecida; de Oliveira Longatti, Silvia Maria; de Sousa Soares, Cláudio Roberto Fonseca; Guimarães Guilherme, Luiz Roberto; de Souza Moreira, Fatima Maria

    2013-11-01

    Increasing concern regarding mining area environmental contamination with heavy metals has resulted in an emphasis of current research on phytoremediation. The aim of the present study was to assess the efficiency of symbiotic Cupriavidus necator strains on different leguminous plants in soil contaminated with heavy metals following the application of inorganic materials. The application of limestone and calcium silicate induced a significant increase in soil pH, with reductions in zinc and cadmium availability of 99 and 94 %, respectively. In addition, improved nodulation of Mimosa caesalpiniaefolia, Leucaena leucocephala and Mimosa pudica in soil with different levels of contamination was observed. Significant increases in the nitrogen content of the aerial parts of the plant were observed upon nodulation of the root system of Leucaena leucocephala and Mimosa pudica by strain UFLA01-659 (36 and 40 g kg(-1)) and by strain UFLA02-71 in Mimosa caesalpiniaefolia (39 g kg(-1)). The alleviating effect of calcium silicate resulted in higher production of dry matter from the aerial part of the plant, an increase in nodule number and an increase in the nitrogen fixation rate. The results of the present study demonstrate that the combination of rhizobia, leguminous plants and calcium silicate may represent a key factor in the remediation of areas contaminated by heavy metals.

  19. Autoregulation of nodulation interferes with impacts of nitrogen fertilization levels on the leaf-associated bacterial community in soybeans.

    Science.gov (United States)

    Ikeda, Seishi; Anda, Mizue; Inaba, Shoko; Eda, Shima; Sato, Shusei; Sasaki, Kazuhiro; Tabata, Satoshi; Mitsui, Hisayuki; Sato, Tadashi; Shinano, Takuro; Minamisawa, Kiwamu

    2011-03-01

    The diversities leaf-associated bacteria on nonnodulated (Nod(-)), wild-type nodulated (Nod(+)), and hypernodulated (Nod(++)) soybeans were evaluated by clone library analyses of the 16S rRNA gene. To analyze the impact of nitrogen fertilization on the bacterial leaf community, soybeans were treated with standard nitrogen (SN) (15 kg N ha(-1)) or heavy nitrogen (HN) (615 kg N ha(-1)) fertilization. Under SN fertilization, the relative abundance of Alphaproteobacteria was significantly higher in Nod(-) and Nod(++) soybeans (82% to 96%) than in Nod(+) soybeans (54%). The community structure of leaf-associated bacteria in Nod(+) soybeans was almost unaffected by the levels of nitrogen fertilization. However, differences were visible in Nod(-) and Nod(++) soybeans. HN fertilization drastically decreased the relative abundance of Alphaproteobacteria in Nod(-) and Nod(++) soybeans (46% to 76%) and, conversely, increased those of Gammaproteobacteria and Firmicutes in these mutant soybeans. In the Alphaproteobacteria, cluster analyses identified two operational taxonomic units (OTUs) (Aurantimonas sp. and Methylobacterium sp.) that were especially sensitive to nodulation phenotypes under SN fertilization and to nitrogen fertilization levels. Arbuscular mycorrhizal infection was not observed on the root tissues examined, presumably due to the rotation of paddy and upland fields. These results suggest that a subpopulation of leaf-associated bacteria in wild-type Nod(+) soybeans is controlled in similar ways through the systemic regulation of autoregulation of nodulation, which interferes with the impacts of N levels on the bacterial community of soybean leaves.

  20. The Medicago truncatula lysin [corrected] motif-receptor-like kinase gene family includes NFP and new nodule-expressed genes.

    Science.gov (United States)

    Arrighi, Jean-François; Barre, Annick; Ben Amor, Besma; Bersoult, Anne; Soriano, Lidia Campos; Mirabella, Rossana; de Carvalho-Niebel, Fernanda; Journet, Etienne-Pascal; Ghérardi, Michèle; Huguet, Thierry; Geurts, René; Dénarié, Jean; Rougé, Pierre; Gough, Clare

    2006-09-01

    Rhizobial Nod factors are key symbiotic signals responsible for starting the nodulation process in host legume plants. Of the six Medicago truncatula genes controlling a Nod factor signaling pathway, Nod Factor Perception (NFP) was reported as a candidate Nod factor receptor gene. Here, we provide further evidence for this by showing that NFP is a lysin [corrected] motif (LysM)-receptor-like kinase (RLK). NFP was shown both to be expressed in association with infection thread development and to be involved in the infection process. Consistent with deviations from conserved kinase domain sequences, NFP did not show autophosphorylation activity, suggesting that NFP needs to associate with an active kinase or has unusual functional characteristics different from classical kinases. Identification of nine new M. truncatula LysM-RLK genes revealed a larger family than in the nonlegumes Arabidopsis (Arabidopsis thaliana) or rice (Oryza sativa) of at least 17 members that can be divided into three subfamilies. Three LysM domains could be structurally predicted for all M. truncatula LysM-RLK proteins, whereas one subfamily, which includes NFP, was characterized by deviations from conserved kinase sequences. Most of the newly identified genes were found to be expressed in roots and nodules, suggesting this class of receptors may be more extensively involved in nodulation than was previously known.

  1. Formation of calcareous nodules in loess-paleosol sequences: Reviews of existing models with a proposed new "per evapotranspiration model"

    Science.gov (United States)

    Li, Yanrong; Zhang, Weiwei; Aydin, Adnan; Deng, Xiaohong

    2018-04-01

    Loess is a product of aeolian deposition during Quaternary glaciation cycles. Loess-paleosol sequences are rich in calcareous nodules (CNs). In the literature, two models are widely cited for the formation of CNs, namely "per descendum" and "per ascendum". However, there has been no direct testing or monitoring to support either of these contradictory models. This paper reviews a large number of multidisciplinary literature to evaluate the consistency, reliability and rationality of these two models. Three main conclusions are drawn: (1) the causative factors (variation of pH value along loess-paleosol sequence, decrease of CO2 partial pressure, and reduction of solvent water) that are used to support the per descendum model do not completely explain the supersaturation of infiltration solution with CaCO3, thereby making this model questionable; (2) the per ascendum model explains the formation of CNs along narrow horizons through upward evaporation; however, it fails to produce sporadic distributions and irregular shapes of nodules on loess slope faces and the frequent appearance of nodules around plant roots. In order to reconcile these deficiencies, we conducted an extensive field survey in various parts of Shanxi province. Based on this new set of observations, it was concluded that the "per ascendum" model can be extended to explain all occurrences of CNs. This extended model is called "per evapotranspiration".

  2. Detection, Characterization, and Biological Effect of Quorum-Sensing Signaling Molecules in Peanut-Nodulating Bradyrhizobia

    Directory of Open Access Journals (Sweden)

    Walter Giordano

    2012-03-01

    Full Text Available Bacteria of the genus Bradyrhizobium are able to establish a symbiotic relationship with peanut (Arachis hypogaea root cells and to fix atmospheric nitrogen by converting it to nitrogenous compounds. Quorum sensing (QS is a cell-cell communication mechanism employed by a variety of bacterial species to coordinate behavior at a community level through regulation of gene expression. The QS process depends on bacterial production of various signaling molecules, among which the N-acylhomoserine lactones (AHLs are most commonly used by Gram-negative bacteria. Some previous reports have shown the production of QS signaling molecules by various rhizobia, but little is known regarding mechanisms of communication among peanut-nodulating strains. The aims of this study were to identify and characterize QS signals produced by peanut-nodulating bradyrhizobial strains and to evaluate their effects on processes related to cell interaction. Detection of AHLs in 53 rhizobial strains was performed using the biosensor strains Agrobacterium tumefaciens NTL4 (pZLR4 and Chromobacterium violaceum CV026 for AHLs with long and short acyl chains, respectively. None of the strains screened were found to produce AHLs with short acyl chains, but 14 strains produced AHLs with long acyl chains. These 14 AHL-producing strains were further studied by quantification of β-galactosidase activity levels (AHL-like inducer activity in NTL4 (pZLR4. Strains displaying moderate to high levels of AHL-like inducer activity were subjected to chemical identification of signaling molecules by high-performance liquid chromatography coupled to mass spectrometry (LC-MS/MS. For each AHL-producing strain, we found at least four different AHLs, corresponding to N-hexanoyl-DL-homoserine lactone (C6, N-(3-oxodecanoyl-L-homoserine lactone (3OC10, N-(3-oxododecanoyl-L-homoserine lactone (3OC12, and N-(3-oxotetradecanoyl-L-homoserine lactone (3OC14. Biological roles of 3OC10, 3OC12, and 3OC14 AHLs

  3. Cooled microwave ablation of thyroid nodules: Initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Korkusuz, Yücel [Department of Nuclear Medicine, University Hospital Frankfurt (Germany); Mader, Oscar Maximilian, E-mail: info@dzta.de [Department of Nuclear Medicine, University Hospital Frankfurt (Germany); Kromen, Wolfgang [Department of Neuro Radiology University Hospital (Germany); Happel, Christian [Department of Nuclear Medicine, University Hospital Frankfurt (Germany); German Centre for Thermoablation of Thyroid Nodules, University Hospital, Frankfurt (Germany); Ahmad, Shadi [Department of General and Visceral Surgery, Agaplesion Elisabethenstift, Darmstadt (Germany); Gröner, Daniel; Koca, Mithat; Mader, Alexander [Department of Nuclear Medicine, University Hospital Frankfurt (Germany); Grünwald, Frank; Korkusuz, Hüdayi [Department of Nuclear Medicine, University Hospital Frankfurt (Germany); German Centre for Thermoablation of Thyroid Nodules, University Hospital, Frankfurt (Germany)

    2016-11-15

    Highlights: • cMWA is a safe and effective treatment for thyroid nodules. • Ultrasound imaging allows guidance during microwave ablation. • Pain level during cMWA treatment is reduced in comparison to RFA. - Abstract: Objective: To evaluate if internally cooled microwave ablation (cMWA) is a safe and effective method for treatment of benign and malign thyroid nodules. Methods: 9 patients with 11 symptomatic cold benign thyroid nodules and 1 recurrent thyroid carcinoma ranging in volume from 9.1 to 197 ml (mean size 52 ±  57 ml) were treated with cMWA. The mean age of the patients was 59 years. Pain during the treatment was measured on a 10-point scale. Side effects revealed by ultrasound or patients’ complaints were documented. Periablative efficacy was measured 24 h after cMWA as change (Δ) in serum thyreoglobulin (Tg). Nodule elasticity was measured on a 4-point scale, blood circulation and echogenicity on a 3-point scale. Results: All patients tolerated cMWA well. Median pain intensity averaged 2.1 ± 0.8 (range: 1–3). Postablative hematoma was observed in all cases. In no cases ablation led to hoarseness, superficial burns, nodule ruptures, vagal reactions or dysphagia. cMWA lead to a significant decrease of blood circulation, nodule echogenicity and a significant increase of elasticity (Δ  =  1.1  ±  0.33; 0.8  ±  0.4 and 1.1  ±  0.6 points)(p < 0.05). An average increase of 4495 ng/ml Tg was measured (p < 0.05). Conclusions: cMWA is an effective and secure method for treatment of thyroid nodules.

  4. Nódulo de tiroides Thyroid nodule

    Directory of Open Access Journals (Sweden)

    Silvia Elena Turcios Tristá

    2012-12-01

    Full Text Available En los últimos años se ha incrementado la frecuencia diagnóstica del nódulo de tiroides. Un adecuado método clínico y algunos exámenes complementarios, serán los factores a tener en cuenta para definir la naturaleza de la lesión y su funcionalidad. En la actualidad se adicionan nuevos elementos en los estudios por imagen que ayudan a predecir, en alguna medida, el riesgo de malignidad de estas lesiones, y se trata de que el resultado citológico sea más uniforme y orientador. Las conductas se adecuan al tipo de enfermedad tiroidea y a sus riesgos, pero es imprescindible la unión de las especialidades que tienen que ver con la enfermedad nodular tiroidea, para unificar criterios que favorezcan un adecuado y eficiente proceso diagnóstico-terapéutico, que reduzcan los riesgos y los costos que implica la adopción de conductas inadecuadas e innecesarias.In the last few years, the frequency of diagnosis of the thyroid nodule has increased. A correct clinical method and some supplementary tests are the factors to be taken into account to define the nature of lesion and functionality. At present, new elements are added to the imaging studies, which help to predict somehow the risk of malignancy of these lesions, and it is intended to reach a more uniform and guiding cytological result. The behaviors should adapt to the type of thyroid disease and to the risks, but the combination of those specialties that have to do with the nodular thyroid disease is indispensable in order to uniform criteria favoring adequate and efficient diagnostic and therapeutic processes, and reducing the risks and costs of the adoption of inadequate and unnecessary behaviors.

  5. Rhizobium altiplani sp. nov., isolated from effective nodules on Mimosa pudica growing in untypically alkaline soil in central Brazil.

    Science.gov (United States)

    Baraúna, Alexandre C; Rouws, Luc F M; Simoes-Araujo, Jean L; Dos Reis Junior, Fábio B; Iannetta, Pietro P M; Maluk, Marta; Goi, Silvia R; Reis, Veronica M; James, Euan K; Zilli, Jerri E

    2016-10-01

    Root nodule bacteria were isolated from nodules on Mimosa pudica L. growing in neutral-alkaline soils from the Distrito Federal in central Brazil. The 16S rRNA gene sequence analysis of 10 strains placed them into the genus Rhizobium with the closest neighbouring species (each with 99 % similarity) being Rhizobium grahamii, Rhizobium cauense, Rhizobium mesoamericanum and Rhizobium tibeticum. This high similarity, however, was not confirmed by multi-locus sequence analysis (MLSA) using three housekeeping genes (recA, glnII and rpoB), which revealed R. mesoamericanum CCGE 501T to be the closest type strain (92 % sequence similarity or less). Chemotaxonomic data, including fatty acid profiles [with majority being C19 : 0 cyclo ω8c and summed feature 8 (C18 : 1ω7c/C18 : 1ω6c)], DNA G+C content (57.6 mol%), and carbon compound utilization patterns supported the placement of the novel strains in the genus Rhizobium. Results of average nucleotide identity (ANI) differentiated the novel strains from the closest species of the genus Rhizobium, R. mesoamericanum, R. grahamii and R. tibeticum with 89.0, 88.1 and 87.8 % similarity, respectively. The symbiotic genes essential for nodulation (nodC) and nitrogen fixation (nifH) were most similar (99-100 %) to those of R. mesoamericanum, another Mimosa-nodulating species. Based on the current data, these 10 strains represent a novel species of the genus Rhizobium for which the name Rhizobium altiplani sp. nov. is proposed. The type strain is BR 10423T (=HAMBI 3664T).

  6. Thyroid nodule recognition in computed tomography using first order statistics.

    Science.gov (United States)

    Peng, Wenxian; Liu, Chenbin; Xia, Shunren; Shao, Dangdang; Chen, Yihong; Liu, Rui; Zhang, Zhiping

    2017-06-02

    Computed tomography (CT) is one of the popular tools for early detection of thyroid nodule. The pixel intensity of thyroid in CT image is very important information to distinguish nodule from normal thyroid tissue. The pixel intensity in normal thyroid tissues is homogeneous and smooth. In the benign or malignant nodules, the pixel intensity is heterogeneous. Several studies have shown that the first order features in ultrasound image can be used as imaging biomarkers in nodule recognition. In this paper, we investigate the feasibility of utilizing the first order texture features to identify nodule from normal thyroid tissue in CT image. A total of 284 thyroid CT images from 113 patients were collected in this study. We used 150 healthy controlled thyroid CT images from 55 patients and 134 nodule images (50 malignant and 84 benign nodules) from 58 patients who have undergone thyroid surgery. The final diagnosis was confirmed by histopathological examinations. In the presented method, first, regions of interest (ROIs) from axial non-enhancement CT images were delineated manually by a radiologist. Second, average, median, and wiener filter were applied to reduce photon noise before feature extraction. The first-order texture features, including entropy, uniformity, average intensity, standard deviation, kurtosis and skewness were calculated from each ROI. Third, support vector machine analysis was applied for classification. Several statistical values were calculated to evaluate the performance of the presented method, which includes accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area of under receiver operating characteristic curve (AUC). The entropy, uniformity, mean intensity, standard deviation, skewness (P < 0.05), except kurtosis (P = 0.104) of thyroid tissue with nodules have a significant difference from those of normal thyroid tissue. The optimal classification was obtained from the presented

  7. Thyroid Nodules Individual Pathologic Assessment in Imam Reza Hospital Tabriz

    Directory of Open Access Journals (Sweden)

    Saeed Judi

    2017-02-01

    Full Text Available Background and Objectives: Single thyroid nodule is a common clinical finding in patients with thyroid gland enlargment or with palpable mass in anterior neck. Because of various pathologic kinds and wide spectrum of nodules from inflammatory disease to benign and malignan tumors, pathologically diagnosis of disease is very important because treatment, prognosiss and approach will differ with respect to diagnosis. Because of importance and high incidence of disease, we decided to investigate records of patients in pathology department of Imam Reza hospital of Tabriz between 2011-14. Our goals were determination of pathologic incidence of single thyroid nodules and investigation of them by sex and age. After extracting results from records, we presented them in the form of tables and figure. Material and Methods: In total, 17349 patients referred to pathology department of Imam Reza hospital between 2011-14. In 191 cases the first clinical diagnosiss was single thyroid nodule. Thyroids specimes were sent to pathology department. Results: The most common pathologic report was multinodular goiter in 90 patients (47%. Other kinds were follicular adenoma 28%, papillary carcinoma 15%, follicular carcinoma and diffuse goiter 3%, lymphocytic thyroiditis, medulary carcinoma 1%, granuloma, lymphoma and abscess each one 0.5%, respectively. Conclusion: Most cases of thyroid nodules are nodular goiter and it is prevalent among females.

  8. Multicellular contractility contributes to the emergence of mesothelioma nodules

    Science.gov (United States)

    Czirok, Andras

    Malignant pleural mesothelioma (MPM) nodules arise from the mesothelial lining of the pleural cavity by a poorly understood mechanism. We demonstrate that macroscopic multicellular aggregates, reminiscent of the MPM nodules found in patients, develop when MPM cell lines are cultured at high cell densities for several weeks. Surprisingly, the nodule-like aggregates do not arise by excessive local cell proliferation, but by myosin II-driven cell contractility. Contractile nodules contain prominent actin cables that can span several cells. Several features of the in vitro MPM nodule development can be explained by a computational model that assumes uniform and steady intercellular contractile forces within a monolayer of cells, and a mechanical load-dependent lifetime of cell-cell contacts. The model behaves as a self-tensioned Maxwell fluid and exhibits an instability that leads to pattern formation. Altogether, our findings suggest that inhibition of the actomyosin system may provide a hitherto not utilized therapeutic approach to affect MPM growth. NIH R01-GM102801.

  9. Thyroid nodules with nondiagnostic results on repeat fine-needle aspiration biopsy: which nodules should be considered for repeat biopsy or surgery rather than follow-up?

    Energy Technology Data Exchange (ETDEWEB)

    Eun, Na Lae; Chang, Hang Seok; Gweon, Hye Mi; Kim, Jeong Ah; Youk, Ji Hyun; Son, Eun Jun [Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Yoo, Mi Ri [Dept. of Radiology, Dongjak Kyunghee Hospital, Seoul (Korea, Republic of); Park, Ah Young [Dept. of Radiology, Korea University Ansan Hospital, Korea University College of Medicine, Ansan (Korea, Republic of); Moon, Hee Jung [Dept. of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2016-07-15

    The goal of this study was to assess the clinicopathologic and ultrasonographic features of thyroid nodules with nondiagnostic results on repeat ultrasonography (US)-guided fineneedle aspiration biopsy (FNAB) according to size and the number of suspicious findings and to determine the proper management of nodules with consecutive nondiagnostic results. This retrospective study included 297 nodules with nondiagnostic results on repeat FNAB that were evaluated by US over the course of at least 12 months of follow-up, a follow-up biopsy, or an operation. We compared clinical and US variables between benign and malignant nodules in thyroid nodules with repeat nondiagnostic results. The comparison of benign and malignant nodules with repeat nondiagnostic results revealed that age, marked hypoechogenicity, irregular or microlobulated margins, microcalcifications, and nonparallel shape were significantly associated with malignancy. Multivariate logistic regression analysis in malignant nodules revealed that microcalcifications and irregular or microlobulated margins were independently associated with malignancy. Among them, only irregular or microlobulated margins were independently significant as a predictor of malignancy in repeatedly nondiagnostic nodules measuring >10 mm. Using receiver operating characteristic analysis, the best cutoff value for the “number of suspicious findings” between benign and malignant nodules was three in nodules of all sizes, three in nodules measuring ≤10 mm, and two in nodules measuring >10 mm. Irregular or microlobulated margins may be the most frequent US features in repeatedly nondiagnostic nodules >10 mm. The presence of “two or more suspicious findings” can be used as the cutoff for distinguishing benign and malignant nodules.

  10. Variability of Mn, Fe, Ni, Cu and Co in manganese nodules from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Jauhari, P.

    The trace element variations in manganese nodules from the Central Indian Basin have been related to the underlying sediment type. Percentages of Mn, Cu and Ni are high in nodules occurring in siliceous sediments compared with nodules from the red...

  11. Seedling root targets

    Science.gov (United States)

    Diane L. Haase

    2011-01-01

    Roots are critical to seedling performance after outplanting. Although root quality is not as quick and simple to measure as shoot quality, target root characteristics should be included in any seedling quality assessment program. This paper provides a brief review of root characteristics most commonly targeted for operational seedling production. These are: root mass...

  12. Usefulness of the CAD System for Detecting Pulmonary Nodule in Real Clinical Practice

    International Nuclear Information System (INIS)

    Song, Kyoung Doo; Chung, Myung Jin; Kim, Hee Cheol; Lee, Kyung Soo; Jeong, Sun Young

    2011-01-01

    We wanted to evaluate the usefulness of the computer-aided detection (CAD) system for detecting pulmonary nodules in real clinical practice by using the CT images. Our Institutional Review Board approved our retrospective study with a waiver of informed consent. This study included 166 CT examinations that were performed for the evaluation of pulmonary metastasis in 166 patients with colorectal cancer. All the CT examinations were interpreted by radiologists and they were also evaluated by the CAD system. All the nodules detected by the CAD system were evaluated with regard to whether or not they were true nodules, and they were classified into micro nodules (MN, diameter < 4 mm) and significant nodules (SN, 4 ≤ diameter ≤ 10 mm). The radiologic reports and CAD results were compared. The CAD system helped detect 426 nodules: 115 (27%) of the 426 nodules were classified as true nodules and 35 (30%) of the 115 nodules were SNs, and 83 (72%) of the 115 were not mentioned in the radiologists' reports and three (4%) of the 83 nodules were non-calcified SNs. One of three non-calcified SNs was confirmed as a metastatic nodule. According to the radiologists' reports, 60 true nodules were detected, and 28 of the 60 were not detected by the CAD system. Although the CAD system missed many SNs that are detected by radiologists, it helps detect additional nodules that are missed by the radiologists in real clinical practice. Therefore, the CAD system can be useful to support a radiologist's detection performance

  13. Prognosis of thyroid nodules in individuals living in the Zhitomir region of Ukraine.

    Directory of Open Access Journals (Sweden)

    Naomi Hayashida

    Full Text Available After the accident at the Chernobyl Nuclear Power Plant (CNPP, the incidence of thyroid cancer increased among children. Recently, a strong relationship between solid thyroid nodules and the incidence of thyroid cancer was shown in atomic bomb survivors. To assess the prognosis of benign thyroid nodules in individuals living in the Zhitomir region of Ukraine, around the CNPP, we conducted a follow-up investigation of screening data from 1991 to 2000 in the Ukraine.Participants of this study were 160 inhabitants with thyroid nodules (nodule group and 160 inhabitants without thyroid nodules (normal control group intially identified by ultrasonography from 1991 to 2000. All participants were aged 0 to 10 years old and lived in the same area at the time of the accident. We performed follow-up screening of participants and assessed thyroid nodules by fine needle aspiration biopsy.Among the nodule group participants, the number and size of nodules were significantly increased at the follow-up screening compared with the initial screening. No thyroid nodules were observed among the normal control group participants. The prevalence of thyroid abnormality, especially nodules that could be cancerous (malignant or suspicious by fine needle aspiration biopsy, was 7.5% in the nodule group and 0% in the normal control group (P<0.001.Our study indicated that a thyroid nodule in childhood is a prognostic factor associated with an increase in the number and size of nodules in individuals living in the Zhitomir region of Ukraine.

  14. Mucoid impaction presenting as multiple pulmonary nodules in cystic fibrosis

    International Nuclear Information System (INIS)

    Carpenter, L.D.; Lambie, N.K.; Wilsher, M.L.

    1996-01-01

    Mucoid impaction has been described as a complication of asthma and more commonly in patients with allergic bronchopulmonary aspergillosis. In such cases, the impacted pools of mucus may present as discrete nodules on chest X-ray and hence simulate the appearance of metastatic malignancy. A case of mucoid impaction presenting as multiple pulmonary nodules in a patient with cystic fibrosis is described. The chest X-ray showed hyperinfiltration and scattered changes consistent with bronchiectasis. Computed tomography scan confirmed these and additional intra-pulmonary nodular densities. This report illustrates that mucus impaction as a cause of pulmonary nodules should be considered in any patient with chronic lung disease characterised by excess mucus production. 6 refs., 3 figs

  15. Nonsurgical, image-guided, minimally invasive therapy for thyroid nodules

    DEFF Research Database (Denmark)

    Gharib, Hossein; Hegedüs, Laszlo; Pacella, Claudio Maurizio

    2013-01-01

    Context: Nodular thyroid disease is very common. Most nodules are asymptomatic, are benign by fine-needle aspiration, remain stable, and can be followed by observation alone in the majority of the patients. Occasionally, nodules grow or cause symptoms requiring treatment. So far, surgery has been...... our main option for treatment. Objective: In this review, we discuss nonsurgical, minimally invasive approaches for small thyroid masses, including indications, efficacy, side effects, and costs. Evidence Acquisition: We selected recent publications related to minimally invasive thyroid techniques...... therapy is recommended for recurrent benign thyroid cysts. Either ultrasound-guided laser or radiofrequency ablation can be used for symptomatic solid nodules with normal or abnormal thyroid function. Microwave ablation and high-intensity focused ultrasound are newer approaches that need further clinical...

  16. Malignancy risk estimation of pulmonary nodules in screening CTs

    DEFF Research Database (Denmark)

    van Riel, Sarah J; Ciompi, Francesco; Winkler Wille, Mathilde M

    2017-01-01

    PURPOSE: To compare human observers to a mathematically derived computer model for differentiation between malignant and benign pulmonary nodules detected on baseline screening computed tomography (CT) scans. METHODS: A case-cohort study design was chosen. The study group consisted of 300 chest CT...... scans from the Danish Lung Cancer Screening Trial (DLCST). It included all scans with proven malignancies (n = 62) and two subsets of randomly selected baseline scans with benign nodules of all sizes (n = 120) and matched in size to the cancers, respectively (n = 118). Eleven observers and the computer....... Differences in morphological features between malignant and size-matched benign nodules were analyzed using chi-square analysis with Bonferroni correction. A significant difference was defined at p

  17. Solitary pulmonary nodule by pulmonary hematoma under warfarin therapy

    International Nuclear Information System (INIS)

    Scheppach, W.; Kulke, H.; Liebau, G.; Braun, H.; Wuerzburg Univ.

    1983-01-01

    Pulmonary hematoma is a rare cause of a pulmonary nodule. Mostly it results from penetrating or blunt chest injuries. The case of a patient is reported, whose chest X-ray showed a pulmonary nodule suspected of malignancy. This patient was maintained permanently on anticoagulants (warfarin derivates) after cardiac valve replacement with a prosthesis. A definite diagnosis could not be established by non-invasive methods. A needle biopsy of the lung was impracticable because of the location of the pulmonary lesion; an exploratory thoracotomy could not be carried out due to a general indication of nonoperability. Control examinations showed that the pulmonary nodule had vanished completely within four months. In consideration of the patient's clinical situation it can be concluded that the pulmonary lesion was caused by a hematoma of the lung. (orig.) [de

  18. Undercooling and nodule count in thin walled ductile iron castings

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2007-01-01

    Casting experiments have been performed with eutectic and hypereutectic castings with plate thick¬nesses from 2 to 8 mm involving both temperature measurements during solidification and micro¬structural examination afterwards. The nodule count was the same for the eutectic and hypereutectic...... castings in the thin plates ( 4.3 mm) while in the 8 mm plate the nodule count was higher in the hypereutectic than in the eutectic castings. The minimum temperature prior to the eutectic recalescence (Tmin) was 15 to 20C lower for the eutectic than the hypereutectic castings. This is due to nucleation...... of graphite nodules which begins at a lover temperature in the eutectic than in the hypereutectic castings The recalescence (Trec) was however also larger for the eutectic casting and in the thin plates the maximum temperature after recalescence (Tmax) was the same in the eutectic and hypereutectic plates...

  19. Electrochemical polarization studies of nodulation phenomenon during copper electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Lafront, A-M.; Veilleux, B.; Ghali, E. [Laval Univ., Dept. of Mining, Metallurgy and Material Engineering, Sainte-Foy, Quebec (Canada)

    2001-07-01

    The use of thiourea, gelatin and chloride additives during copper electrorefining promotes smooth cathode deposits, but inappropriate additive concentrations and/or molar ratios can lead to nodule formation, when operating at current densities slightly higher than 300 A/m{sup 2} and at 65{sup o}C. In voltammograms at potential sweep rates of 0.05 mV/s, a limiting current density was observed for a cathode potential range of the order of 50 mV. Galvanostatic polarization measurements followed by microscopic examination proved this to be related to nodule formation. A diagram was conceived to delineate current densities for nodule-free copper deposit as functions of the concentrations and molar ratios of the additives. (author)

  20. Transcription of the soybean leghemoglobin genes during nodule development

    DEFF Research Database (Denmark)

    Marcker, Anne; Lund, Marianne; Jensen, Erik Ø

    1984-01-01

    During the early stages of soybean nodule development the leghemoglobin (Lb) genes are activated sequentially in the opposite order to which they are arranged in the soybean genome. At a specific stage after the initial activation of all the Lb genes, a large increment occurs in the transcription...... of the Lb(c1), Lb(c3) and Lb(a) genes while the transcription of the Lb(c2) gene is not amplified to a similar extent. All the Lb genes retain significant activity for a long period during the lifetime of a nodule. Consequently the soybean Lb genes are not regulated by a developmental gene switching...... mechanism as is the case for vertebrate globin genes. Concomitantly with the increase in Lb gene transcription some of the other nodule specific plant genes are activated. These specific changes in the activities of the Lb and nodulin genes precede the activation of the bacterial nitrogenase gene. Thus...