Journal articles on the topic 'Nodulation'
To see the other types of publications on this topic, follow the link: Nodulation.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Nodulation.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
van Spronsen, Paulina C., Teun Tak, Anita M. M. Rood, Anton A. N. van Brussel, Jan W. Kijne, and Kees J. M. Boot. "Salicylic Acid Inhibits Indeterminate-Type Nodulation But Not Determinate-Type Nodulation." Molecular Plant-Microbe Interactions® 16, no. 1 (January 2003): 83–91. http://dx.doi.org/10.1094/mpmi.2003.16.1.83.
Full textAbstract:
LCOs (lipochitin oligosaccharides, Nod factors) produced by the rhizobial symbiote of Vicia sativa subsp. nigra (vetch, an indeterminate-type nodulating plant) are mitogenic when carrying an 18:4 acyl chain but not when carrying an 18:1 acyl chain. This suggests that the 18:4 acyl chain specifically contributes to signaling in indeterminate-type nodulation. In a working hypothesis, we speculated that the 18:4 acyl chain is involved in oxylipin signaling comparable to, for example, signaling by derivatives of the 18:3 fatty acid linolenic acid (the octadecanoid pathway). Because salicylic acid (SA) is known to interfere with oxylipin signaling, we tested whether nodulation of vetch could be affected by addition of 10−4 M SA. This concentration completely blocked nodulation of vetch by Rhizobium leguminosarum bv. viciae and inhibited the mitogenic effect of 18:4 LCOs but did not affect LCO-induced root-hair deformation. SA did not act systemically, and only biologically active SA derivatives were capable of inhibiting nodule formation. SA also inhibited R. leguminosarum bv. viciae association with vetch roots. In contrast, addition of SA to Lotus japonicus (a determinate-type nodulating plant responding to 18:1 LCOs) did not inhibit nodulation by Mesorhizobium loti. Other indeterminate-type nodulating plants showed the same inhibiting response toward SA, whereas SA did not inhibit the nodulation of other determinate-type nodulating plants. SA may be a useful tool for studying fundamental differences between signal transduction pathways of indeterminate- and determinate-type nodulating plants.
2
Wu, Zhihua, Hong Liu, Wen Huang, Lisha Yi, Erdai Qin, Tiange Yang, Jing Wang, and Rui Qin. "Genome-Wide Identification, Characterization, and Regulation of RWP-RK Gene Family in the Nitrogen-Fixing Clade." Plants 9, no. 9 (September 11, 2020): 1178. http://dx.doi.org/10.3390/plants9091178.
Full textAbstract:
RWP-RK is a plant-specific family of transcription factors, involved in nitrate response, gametogenesis, and nodulation. However, genome-wide characterization, phylogeny, and the regulation of RWP-RK genes in the nodulating and non-nodulating plant species of nitrogen-fixing clade (NFC) are widely unknown. Therefore, we identified a total of 292 RWP-RKs, including 278 RWP-RKs from 25 NFC species and 14 RWP-RKs from the outgroup, Arabidopsis thaliana. We classified the 292 RWP-RKs in two subfamilies: the NIN-like proteins (NLPs) and the RWP-RK domain proteins (RKDs). The transcriptome and phylogenetic analysis of RWP-RKs suggested that, compared to RKD genes, the NLP genes were just upregulated in nitrate response and nodulation. Moreover, nodule-specific NLP genes of some nodulating NFC species may have a common ancestor (OG0002084) with AtNLP genes in A. thaliana. Further, co-expression networks of A.thaliana under N-starvation and N-supplementation conditions revealed that there is a higher correlation between expression of AtNLP genes and symbiotic genes during N-starvation. In P. vulgaris, we confirmed that N-starvation stimulated nodulation by regulating expression of PvNLP2, closely related to AtNLP6 and AtNLP7 with another common origin (OG0004041). Taken together, we concluded that different origins of the NLP genes involved in both N-starvation response and specific expression of nodulation would contribute to the evolution of nodulation in NFC plant species. Our results shed light on the phylogenetic relationships of NLP genes and their differential regulation in nitrate response of A. thaliana and nodulation of NFC.
3
Zhao, Jingya, Yi Meng, Chun Li, and Jun Tie. "The effect of nodulation on the distribution of concentration and current density during copper electrolytic refining." Journal of Physics: Conference Series 2285, no. 1 (June 1, 2022): 012015. http://dx.doi.org/10.1088/1742-6596/2285/1/012015.
Full textAbstract:
Abstract During the industrial copper electrolytic refining process, the suspended particles in the electrolyte are adsorbed on the surface of the cathode and form nodulations, leading to the disturbance of the normal state in the electrolyte. When nodulations grow and then contact with the anode, short circuits occurs. It reduce current efficiency and product quality. In this paper, the concentration and current density changes in the nodulation surface and the anode surface is proposed. The current density on the nodulation is the largest and the concentration is the smallest.
4
Bano, Asghari, and James E. Harper. "Plant growth regulators and phloem exudates modulate root nodulation of soybean." Functional Plant Biology 29, no. 11 (2002): 1299. http://dx.doi.org/10.1071/fp02031.
Full textAbstract:
A time-course study was conducted on the effect of synthetic ABA and phloem exudate on root nodulation, nitrogenase activity, and dry matter content of pouch-grown soybean [Glycine max (L.) Merr.]. A hypernodulating mutant (NOD1-3) derived from the cultivar Williams was evaluated. The normally-nodulating cultivar Williams 82 served as the control. All phases of nodulation (nodule initiation, development and function) were inhibited by 1–50 μM synthetic ABA treatment of roots of pouch-grown soybean. The ABA effect was more pronounced for the treatment made 24 h prior to inoculation. The magnitude of inhibition of nodulation by ABA and by phloem exudate from inoculated Williams 82 was decreased when application was delayed to 48 h post-inoculation. Synthetic indoleacetic acid and benzyladenine (1 and 5 μM) also inhibited the number of nodules per plant, and the magnitude of inhibition was greater in the normally-nodulating Williams 82 cultivar than in the NOD1-3 hypernodulating mutant. Changes in endogenous free ABA in cotyledons, leaves, and xylem sap of seedlings were monitored at 24-h intervals after inoculation in both lines, and appeared to respond to inoculation. Addition of crude phloem exudate from Williams 82 or hypernodulating NOD1-3 was inhibitory to root nodulation of NOD1-3 — this effect was concentration dependent. Partially-purified (acidic aqueous fraction) phloem exudate from Williams 82 suppressed nodulation in NOD1-3 by 54% (averaged over a 7-d time-course), while partially-purified phloem exudate (acidic aqueous fraction) from NOD1-3 was much less inhibitory (23%). ABA levels in the phloem fractions applied were nearly identical (15.6 vs 16.0 ng mL–1), which indicates that ABA was not directly affecting nodulation control. Partially-purified extract (acidic aqueous fraction) from leaves of nodulated NOD1-3 was much less inhibitory to nodulation of NOD1-3 seedlings than was the comparable fraction from Williams 82. Although free ABA applied exogenously was capable of altering nodulation, it does not appear that endogenous ABA levels directly account for the autoregulatory control of nodulation in soybean. This implies that there may be factor(s) moving in the phloem other than ABA that possibly impact expression of root nodulation. Alternatively, it may be that plant development is responsive to interactions among plant growth regulators mediated by subtle changes in individual hormone concentrations. The possibility remains that normally-nodulating and hypernodulating lines have differential sensitivity to ABA, and that this explains altered nodulation control at similar levels of endogenous ABA.
5
Doyle, Jeff J. "Phylogenetic Perspectives on the Origins of Nodulation." Molecular Plant-Microbe Interactions® 24, no. 11 (November 2011): 1289–95. http://dx.doi.org/10.1094/mpmi-05-11-0114.
Full textAbstract:
Recent refinements to the phylogeny of rosid angiosperms support the conclusion that nodulation has evolved several times in the so-called N2-fixing clade (NFC), and provide dates for these origins. The hypothesized predisposition that enabled the evolution of nodulation occurred approximately 100 million years ago (MYA), was retained in the various lineages that radiated rapidly shortly thereafter, and was functional in its non-nodulation role for at least an additional 30 million years in each nodulating lineage. Legumes radiated rapidly shortly after their origin approximately 60 MYA, and nodulation most likely evolved several times during this radiation. The major lineages of papilionoid legumes diverged close to the time of origin of nodulation, accounting for the diversity of nodule biology in the group. Nodulation symbioses exemplify the concept of “deep homology,” sharing various homologous components across nonhomologous origins of nodulation, largely due to recruitment from existing functions, notably the older arbuscular mycorrhizal symbiosis. Although polyploidy may have played a role in the origin of papilionoid legume nodules, it did not do so in other legumes, nor did the prerosid whole-genome triplication lead directly to the predisposition of nodulation.
6
Ladha, J. K., Minviluz Garcia, R. P. Pareek, and G. Rarivoson. "Relative contributions to nitrogenase (acetylene reducing) activity of stem and root nodules in Sesbania rostrata." Canadian Journal of Microbiology 38, no. 6 (June 1, 1992): 577–83. http://dx.doi.org/10.1139/m92-095.
Full textAbstract:
Six experiments, two each in the phytotron, greenhouse, and field, were conducted to assess the contribution of nitrogenase activity (acetylene reduction) by stem nodules in the presence and absence of root nodules of Sesbania rostrata (Brem & Oberm). In a greenhouse experiment, the effect of detaching already formed aerial stem nodules on the restoration of root nodules and nitrogenase activity was studied. The field experiment compared nodulation and acetylene-reduction activity by dual-nodulating S. rostrata and root-nodulating Sesbania cannabina. Acetylene-reduction activity expressed per gram of nodule dry weight was higher for stem nodules than for root nodules. Root nodule dry weight and acetylene-reduction activity failed to increase after stem inoculation, but root nodule dry weight and acetylene-reduction activity increased several fold within 15 days of detachment of aerial stem nodules. Stem nodulation, which occurred without inoculation under lowland field condition, suppressed root nodulation, thus accounting for more than 75% of total nitrogenase activity. Sesbania rostrata showed higher acetylene-reduction activity than S. cannabina. In dual-nodulating plants, root and stem nodules appeared to strike a balance in competition for energy, which may be controlled by stem nodulation. Key words: Sesbania rostrata, Azorhizobium caulinodans, stem nodule, root nodule, acetylene-reducing activity.
7
Liu, Jieyu, and Ton Bisseling. "Evolution of NIN and NIN-like Genes in Relation to Nodule Symbiosis." Genes 11, no. 7 (July 11, 2020): 777. http://dx.doi.org/10.3390/genes11070777.
Full textAbstract:
Legumes and actinorhizal plants are capable of forming root nodules symbiosis with rhizobia and Frankia bacteria. All these nodulating species belong to the nitrogen fixation clade. Most likely, nodulation evolved once in the last common ancestor of this clade. NIN (NODULE INCEPTION) is a transcription factor that is essential for nodulation in all studied species. Therefore, it seems probable that it was recruited at the start when nodulation evolved. NIN is the founding member of the NIN-like protein (NLP) family. It arose by duplication, and this occurred before nodulation evolved. Therefore, several plant species outside the nitrogen fixation clade have NLP(s), which is orthologous to NIN. In this review, we discuss how NIN has diverged from the ancestral NLP, what minimal changes would have been essential for it to become a key transcription controlling nodulation, and which adaptations might have evolved later.
8
Barran, L. R., E. S. P. Bromfield, and D. C. W. Brown. "Identification and cloning of the bacterial nodulation specificity gene in the Sinorhizobium meliloti Medicago laciniata symbiosis." Canadian Journal of Microbiology 48, no. 9 (September 1, 2002): 765–71. http://dx.doi.org/10.1139/w02-072.
Full textAbstract:
Medicago laciniata (cut-leaf medic) is an annual medic that is highly nodulation specific, nodulating only with a restricted range of Sinorhizobium meliloti, e.g., strain 102L4, but not with most strains that nodulate Medicago sativa (alfalfa), e.g., strains RCR2011 and Rm41. Our aim was to identify and clone the S. meliloti 102L4 gene implicated in the specific nodulation of M. laciniata and to characterize the adjacent nodulation (nod) region. An 11-kb EcoRI DNA fragment from S. meliloti 102L4 was shown to complement strain RCR2011 for nodulation of M. laciniata. Nucleotide sequencing revealed that this fragment contained nodABCIJ genes whose overall arrangement was similar to those found in strains RCR2011 and Rm41, which do not nodulate M. laciniata. Data for Tn5 mutagenesis of the nodABCIJ region of strain 102L4 suggested that the nodC gene was involved in the specific nodulation of M. laciniata. Tn5 insertions in the nodIJ genes gave mutants with nodulation delay phenotypes on both M. laciniata and M. sativa. Only subclones of the 11-kb DNA fragment containing a functional nodC gene from strain 102L4 were able to complement strain RCR2011 for nodulation of M. laciniata. The practical implications of these findings are discussed in the context of the development of a specific M. sativa S. meliloti combination that excludes competition for nodulation by bacterial competitors resident in soil.Key words: Sinorhizobium meliloti, Medicago laciniata, nodulation specificity,nod gene, nucleotide sequence.
9
Asamizu, Erika, Yasukazu Nakamura, Shusei Sato, and Satoshi Tabata. "Comparison of the Transcript Profiles from the Root and the Nodulating Root of the Model Legume Lotus japonicus by Serial Analysis of Gene Expression." Molecular Plant-Microbe Interactions® 18, no. 5 (May 2005): 487–98. http://dx.doi.org/10.1094/mpmi-18-0487.
Full textAbstract:
We performed a comprehensive transcript analysis on the early stage of root nodulation in the model legume Lotus japonicus by serial analysis of gene expression (SAGE). SAGE libraries were made from uninfected roots and nodulating roots abundant in nodule primordia, and 85,482 and 80,233 SAGE tags were recovered, respectively. Comparison of the tag frequency identified 407 tag species that appeared in significantly greater numbers in the nodulating root than in the uninfected root, and the converse was found for 428 tag species. Gene identification of the tags was performed by matching them to L. japonicus expressed sequence tag sequences. We made several novel findings by applying SAGE to transcript analysis of legume root nodulation. A gene that showed the most significant increase in tag number upon nodulation has not been described previously. Different levels of transcription induction among leghemoglobin gene paralogs were found, indicating the effectiveness of SAGE in discriminating different gene family members. We identified genes for 44 unknown tags by means of reverse SAGE. We found 11 antisense tags that increased during nodulation, indicating that regulation of gene expression by antisense transcripts may occur in an organ-dependent manner.
10
Redden, RJ, A. Diatloff, and T. Usher. "Field screening accessions of Phaseolus vulgaris for capacity to nodulate over a range of environments." Australian Journal of Experimental Agriculture 30, no. 2 (1990): 265. http://dx.doi.org/10.1071/ea9900265.
Full textAbstract:
Nineteen lines of Phaseolus vulgaris L. were identified as promising for nodulation ability in a sequence of 2 screenings from 1462 germplasm accessions. These 19 lines plus 4 checks were further evaluated over 4 sites (Rocklea in 1985; Hermitage, Kingaroy and Applethorpe in 1987) and were sown within split-blocks with main treatments of nitrogen fertiliser, inoculum applied, and control with nodulation dependent on indigenous rhizobia. Nitrogen fertiliser significantly suppressed nodulation at Applethorpe and Hermitage sites only. Inoculation with Rhizohium phuseoli strain CC511 was most effective at Applethorpe, the least fertile site. The control nodulated most at Kingaroy. Accession ICA2 1573 was exceptional in its ability to nodulate with indigenous or supplied inoculum, and in the presence of nitrogen fertiliser. This nodulating ability was also shown, less consistently, by accessions Epicure and Amarillo 155. Some accessions were treatment specific for nodulation level: the superior nodulation ability of Campbell 20 was strongly inhibited by nitrogen fertiliser; specific cultivar-Rhizobium strain compatibility was shown by Selection 46, Small White 38, and Red Mexican; BAT1 198 and G6637 were apparently incompatible with Rhizobium strain CC511. Other accessions showed site and treatment specific nodulation responses, while the check entry, Gallaroy, was consistently poor in nodulation throughout the trial.
11
Markwei, Carol M., and Thomas A. LaRue. "Phenotypic characterization of sym8 and sym9, two genes conditioning non-nodulation in Pisum sativum 'Sparkle'." Canadian Journal of Microbiology 38, no. 6 (June 1, 1992): 548–54. http://dx.doi.org/10.1139/m92-090.
Full textAbstract:
Two non-nodulating and non-allelic mutants of P. sativum (L.) 'Sparkle', R25 (sym8) and R72 (sym9), were obtained by γ-radiation. Non-nodulation in each mutant was conditioned by a single recessive gene. Growth analysis indicated that if the mutants were provided with adequate fixed nitrogen, they both had the same growth rate as their nodulating parent, 'Sparkle'. Reciprocal grafts between mutants and parent plants indicated that non-nodulation was controlled by the root genotype. Both mutants induced the common nod genes in rhizobia, and had either higher or similar numbers of rhizobia attached to their roots as had 'Sparkle'. Microscopic studies indicated that root hairs of R72 deformed after inoculation, whereas root hairs of R25 did not show such deformation. In both mutants hair curling, infection thread formation, and nodule meristem initiation did not occur. Key words: mutants, sym genes, nodulation stages, symbiosis.
12
PARK, S. J., and B. R. BUTTERY. "NODULATION MUTANTS OF WHITE BEAN (Phaseolus vulgaris L.) INDUCED BY ETHYL-METHANE SULPHONATE." Canadian Journal of Plant Science 68, no. 1 (January 1, 1988): 199–202. http://dx.doi.org/10.4141/cjps88-019.
Full textAbstract:
Seed of the OAC Rico and Swan Valley cultivars of bean (Phaseolus vulgaris L.) was treated with 0.04 M ethyl-methane sulphonate (EMS). Screening of M2 populations in the presence of 8 mM nitrate + 2 mM ammonium, which substantially inhibited nodulation of the parental cultivars revealed nitrate tolerant supernodulating (ntsn), copious nodulating and non-nodulating mutants. One ntsn mutant from 175 M1 lines of OAC Rico and two ntsn mutants from 467 M1 lines of Swan Valley were obtained. M3 progenies derived from the Rico and the one fertile Swan Valley ntsn-mutants (M2) bred true.Key words: Nodulation, dry edible (navy, common) bean, EMS, Phaseolus vulgaris
13
Nesme, Xavier, Philippe Normand, Francine M. Tremblay, and Maurice Lalonde. "Nodulation speed of Frankia sp. on Alnus glutinosa, Alnus crispa, and Myrica gale." Canadian Journal of Botany 63, no. 7 (July 1, 1985): 1292–95. http://dx.doi.org/10.1139/b85-179.
Full textAbstract:
The question of compatibility between actinorhizal host plants and Frankia sp. was addressed using nodulation speed on Alnus spp. seedlings and Myrica gale seedlings. It was found that the speed of nodulation, defined as the mean time taken for the formation of the first prenodule, was a stable phenotype of both the Frankia strains and the host plants and that a distinction between slow-, medium-, and fast-nodulating Frankia strains could be made. The speed of nodulation of a given Frankia strain did not appear to be positively correlated to the original host plant from which isolation was first performed. It was, however, positively correlated with the Frankia strain and with the host plant species used for inoculation. Some optimal host plant – endophyte combinations were thus defined. Pure spore inocula of Frankia and in vitro propagated Alnus glutinosa plantlets were used to confirm that both the host plant and the microbial partners genetically influenced the nodulation process.
14
Czyż, Katarzyna B., Candy M. Taylor, Michał Kawaliło, and Grzegorz Koczyk. "Gain or Loss? Evidence for Legume Predisposition to Symbiotic Interactions with Rhizobia via Loss of Pathogen-Resistance-Related Gene Families." International Journal of Molecular Sciences 23, no. 24 (December 15, 2022): 16003. http://dx.doi.org/10.3390/ijms232416003.
Full textAbstract:
Nodulation is a hallmark yet non-universal characteristic of legumes. It is unknown whether the mechanisms underlying nitrogen-fixing symbioses evolved within legumes and the broader nitrogen-fixing clade (NFC) repeatedly de novo or based on common ancestral pathways. Ten new transcriptomes representing members from the Cercidoideae and Caesalpinioideae subfamilies were supplemented with published omics data from 65 angiosperms, to investigate how gene content correlates with nodulation capacity within Fabaceae and the NFC. Orthogroup analysis categorized annotated genes into 64150 orthogroups, of which 19 were significantly differentially represented between nodulating versus non-nodulating NFC species and were most commonly absent in nodulating taxa. The distribution of six over-represented orthogroups within Viridiplantae representatives suggested that genomic evolution events causing gene family expansions, including whole-genome duplications (WGDs), were unlikely to have facilitated the development of stable symbioses within Fabaceae as a whole. Instead, an absence of representation of 13 orthogroups indicated that losses of genes involved in trichome development, defense and wounding responses were strongly associated with rhizobial symbiosis in legumes. This finding provides novel evidence of a lineage-specific predisposition for the evolution and/or stabilization of nodulation in Fabaceae, in which a loss of pathogen resistance genes may have allowed for stable mutualistic interactions with rhizobia.
15
Brockwell, J., JA Andrews, RR Gault, LG Gemell, GW Griffith, DF Herridge, JF Holland, et al. "Erratic nodulation and nitrogen fixation in field-grown pigeonpea [Cajanus cajan (L.) Millsp.]." Australian Journal of Experimental Agriculture 31, no. 5 (1991): 653. http://dx.doi.org/10.1071/ea9910653.
Full textAbstract:
Following numerous reports of nodulation failures in pigeonpea [Cajanus cajan (L.) Millsp.] crops in New South Wales, a series of experiments was conducted in glasshouses and at 6 locations in the field. When inoculated seed was grown in moist vermiculite or in sand beds in the glasshouse, pigeonpea nodulated, and fixed N2, normally; but at 3 sites in the field, we could detect neither nodulation nor N2 fixation, despite adequate inoculation or a population of suitable rhizobia in the soil. At another site there was only sporadic occurrence of effective nodules. Nitrogen was fixed at 2 of the 3 field sites on acid soils, but at 1 site it appeared that nodulation was due to a naturally occurring population of soil rhizobia and not to the inoculant. When comparisons were made, pigeonpea was invariably inferior to symbiotically related legumes, cowpea and adzuki bean, in nodulation and N2 fixation. This inferiority was associated with substantially poorer rhizobial colonisation of pigeonpea rhizospheres. The experimental findings confirmed the anecdotal evidence that pigeonpea is an erratically nodulating grain legume on neutral and alkaline soils.
16
Laguerre, Gisèle, Philippe Louvrier, Marie-Reine Allard, and Noëlle Amarger. "Compatibility of Rhizobial Genotypes within Natural Populations of Rhizobium leguminosarum Biovar viciae for Nodulation of Host Legumes." Applied and Environmental Microbiology 69, no. 4 (April 2003): 2276–83. http://dx.doi.org/10.1128/aem.69.4.2276-2283.2003.
Full textAbstract:
ABSTRACT Populations of Rhizobium leguminosarum biovar viciae were sampled from two bulk soils, rhizosphere, and nodules of host legumes, fava bean (Vicia faba) and pea (Pisum sativum) grown in the same soils. Additional populations nodulating peas, fava beans, and vetches (Vicia sativa) grown in other soils and fava bean-nodulating strains from various geographic sites were also analyzed. The rhizobia were characterized by repetitive extragenomic palindromic-PCR fingerprinting and/or PCR-restriction fragment length polymorphism (RFLP) of 16S-23S ribosomal DNA intergenic spacers as markers of the genomic background and PCR-RFLP of a nodulation gene region, nodD, as a marker of the symbiotic component of the genome. Pairwise comparisons showed differences among the genetic structures of the bulk soil, rhizosphere, and nodule populations and in the degree of host specificity within the Vicieae cross-inoculation group. With fava bean, the symbiotic genotype appeared to be the preponderant determinant of the success in nodule occupancy of rhizobial genotypes independently of the associated genomic background, the plant genotype, and the soil sampled. The interaction between one particular rhizobial symbiotic genotype and fava bean seems to be highly specific for nodulation and linked to the efficiency of nitrogen fixation. By contrast with bulk soil and fava bean-nodulating populations, the analysis of pea-nodulating populations showed preferential associations between genomic backgrounds and symbiotic genotypes. Both components of the rhizobial genome may influence competitiveness for nodulation of pea, and rhizosphere colonization may be a decisive step in competition for nodule occupancy.
17
Li, Ronghui, Maggie R. Knox, Anne Edwards, Bridget Hogg, T. H. Noel Ellis, Gehong Wei, and J. Allan Downie. "Natural Variation in Host-Specific Nodulation of Pea Is Associated with a Haplotype of the SYM37 LysM-Type Receptor-Like Kinase." Molecular Plant-Microbe Interactions® 24, no. 11 (November 2011): 1396–403. http://dx.doi.org/10.1094/mpmi-01-11-0004.
Full textAbstract:
Rhizobium leguminosarum bv. viciae, which nodulates pea and vetch, makes a mixture of secreted nodulation signals (Nod factors) carrying either a C18:4 or a C18:1 N-linked acyl chain. Mutation of nodE blocks the formation of the C18:4 acyl chain, and nodE mutants, which produce only C18:1-containing Nod factors, are less efficient at nodulating pea. However, there is significant natural variation in the levels of nodulation of different pea cultivars by a nodE mutant of R. leguminosarum bv. viciae. Using recombinant inbred lines from two pea cultivars, one which nodulated relatively well and one very poorly by the nodE mutant, we mapped the nodE-dependent nodulation phenotype to a locus on pea linkage group I. This was close to Sym37 and PsK1, predicted to encode LysM-domain Nod-factor receptor-like proteins; the Sym2 locus that confers Nod-factor-specific nodulation is also in this region. We confirmed the map location using an introgression line carrying this region. Our data indicate that the nodE-dependent nodulation is not determined by the Sym2 locus. We identified several pea lines that are nodulated very poorly by the R. leguminosarum bv. viciae nodE mutant, sequenced the DNA of the predicted LysM-receptor domains of Sym37 and PsK1, and compared the sequences with those derived from pea cultivars that were relatively well nodulated by the nodE mutant. This revealed that one haplotype (encoding six conserved polymorphisms) of Sym37 is associated with very poor nodulation by the nodE mutant. There was no such correlation with polymorphisms at the PsK1 locus. We conclude that the natural variation in nodE-dependent nodulation in pea is most probably determined by the Sym37 haplotype.
18
Foster, Carol M., William R. Graves, and Harry T. Horner. "Early Nodulin Genes in Japanese Pagodatree (Sophora japonica L.) and American Yellowwood [Cladrastis kentukea (Dum.-Cours.) Rudd]." HortScience 31, no. 4 (August 1996): 615c—615. http://dx.doi.org/10.21273/hortsci.31.4.615c.
Full textAbstract:
Early nodulin genes, such as ENOD2, may be conserved and could function as molecular markers for nodulation. Many nodulating and nonnodulating legumes must be analyzed before the role of such genes in nodulation can be determined. Japanese pagodatree and American yellowwood are closely related, ornamental woody legumes. Unsubstantiated reports of nodulation in Japanese pagodatree require confirmation, and American yellowwood has not been observed to nodulate. We investigated the presence of putative ENOD2 genes in these species, and we are studying differential and temporal expression. Genomic DNA of Japanese pagodatree and primers, derived from proline-rich pentapeptide repeats of conserved ENOD2 sequences, were used to obtain a 555-bp PCR fragment. This cloned fragment was used as a probe for Southern and Northern hybridizations. Genomes of Japanese pagodatree and American yellowwood contained sequences that are similar to ENOD2 sequences in other legumes. Treatments with either cytokinin or an auxin transport inhibitor may induce expression of the putative ENOD2 genes. New data on the characteristics of nodulin genes in woody legumes will clarify the nature and evolution of nodulation in legumes and may have implications for developing sustainable nursery production protocols.
19
Zhang, Rose Y., Baxter Massey, Ulrike Mathesius, and Victoria C. Clarke. "Photosynthetic Gains in Super-Nodulating Mutants of Medicago truncatula under Elevated Atmospheric CO2 Conditions." Plants 12, no. 3 (January 18, 2023): 441. http://dx.doi.org/10.3390/plants12030441.
Full textAbstract:
Legumes are generally considered to be more responsive to elevated CO2 (eCO2) conditions due to the benefits provided by symbiotic nitrogen fixation. In response to high carbohydrate demand from nodules, legumes display autoregulation of nodulation (AON) to restrict nodules to the minimum number necessary to sustain nitrogen supply under current photosynthetic levels. AON mutants super-nodulate and typically grow smaller than wild-type plants under ambient CO2. Here, we show that AON super-nodulating mutants have substantially higher biomass under eCO2 conditions, which is sustained through increased photosynthetic investment. We examined photosynthetic and physiological traits across super-nodulating rdn1-1 (Root Determined Nodulation) and sunn4 (Super Numeric Nodules) and non-nodulating nfp1 (Nod Factor Perception) Medicago truncatula mutants. Under eCO2 conditions, super-nodulating plants exhibited increased rates of carboxylation (Vcmax) and electron transport (J) relative to wild-type and non-nodulating counterparts. The substantially higher rate of CO2 assimilation in eCO2-grown sunn4 super-nodulating plants was sustained through increased production of key photosynthetic enzymes, including Rieske FeS. We hypothesize that AON mutants are carbon-limited and can perform better at eCO2 through improved photosynthesis. Nodulating legumes, especially those with higher nitrogen fixation capability, are likely to out-perform non-nodulating plants under future CO2 conditions and will be important tools for understanding carbon and nitrogen partitioning under eCO2 conditions and future crop improvements.
20
Reddell, P., GD Bowen, and AD Robson. "Nodulation of Casuarinaceae in Relation to Host Species and Soil Properties." Australian Journal of Botany 34, no. 4 (1986): 435. http://dx.doi.org/10.1071/bt9860435.
Full textAbstract:
A field survey was conducted in Australia to examine nodulation of Casuarinaceae in relation to 22 host species (187 sites) and soil chemical properties (152 sites). Four of the five Casuarina species examined were regularly nodulated (most plants in the 60 out of 88 sites in which nodules were found). Casuarina species occurred more frequently on soils of higher available-phosphorus status than did Allocasuarina species, eight of which did not nodulate in any soils. With the nine Allocasuarina species which nodulated,nodules occurred on only a minority of the individual plants examined. Soil chemical properties other than available-phosphorus level were useful in distinguishing sites at which individual species occurred but had no apparent relationship to nodulation. Under glasshouse conditions, baiting of field soils with seedlings of Casuarinaceae indicated the occurrence of nodulation to be similar to that observed in the field survey. Allocasuarina species formed ectomycorrhizas more commonly than did Casuarina species; both genera formed vesicular-arbuscular mycorrhizas. A second glasshouse experiment supported the hypothesis that low phosphorus supply and the absence of infective Frankia were two of the factors responsible for the absence of nodulation in some field soils. The effects of other soil factors in limiting plant growth and nodulation of Casuarinaceae are considered, and the potential significance of N2 fixation by Casuarinaceae in the field discussed. Nodules were found on Allocasuarina campestris, A. dielsrana and A. lehmanniana, not previously recorded as nodulating.
21
Constantin, G. D., M. Grønlund, I. E. Johansen, J. Stougaard, and O. S. Lund. "Virus-Induced Gene Silencing (VIGS) as a Reverse Genetic Tool to Study Development of Symbiotic Root Nodules." Molecular Plant-Microbe Interactions® 21, no. 6 (June 2008): 720–27. http://dx.doi.org/10.1094/mpmi-21-6-0720.
Full textAbstract:
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 distinct non-nodulating phenotype of nin mutants in P. sativum, Lotus japonicus, and Medicago truncatula. The vector based on Pea early browning virus (PEBV) was engineered to carry one of three nonoverlapping fragments (PsNinA, PsNinB, and PsNinC) derived from the PsNin cDNA. Vector inoculation was mediated by agroinfiltration and, 2 weeks later, a Rhizobium leguminosarum bv. viceae culture was added in order to induce root nodulation. At this time point, it was estimated that systemic silencing was established because leaves of reference plants inoculated with PEBV carrying a fragment of Phytoene desaturase displayed photo bleaching. Three weeks after Rhizobium spp. application, plants inoculated with a control vector nodulated normally, whereas nodulation was almost eliminated in plants inoculated with a vector carrying PsNinA and PsNinC. For plants inoculated with a vector carrying PsNinB, 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.
22
Tak, Teun, Paulina C. van Spronsen, Jan W. Kijne, Anton A. N. van Brussel, and Kees J. M. Boot. "Accumulation of Lipochitin Oligosaccharides and NodD-Activating Compounds in an Efficient Plant-Rhizobium Nodulation Assay." Molecular Plant-Microbe Interactions® 17, no. 7 (July 2004): 816–23. http://dx.doi.org/10.1094/mpmi.2004.17.7.816.
Full textAbstract:
During legume plant-Rhizobium spp. interactions, leading to the formation of nitrogen-fixing root nodules, the two ma-or determinants of host plant-specificity are plant-produced nod gene inducers (NodD protein activating compounds) and bacterial lipochitin oligosaccharides (LCOs or Nod factors). In a time course, we describe the accumulation of LCOs in an efficient nodulation assay with Vicia sativa subsp. nigra and Rhizobium leguminosarum, in connection with the presence of NodD-activating compounds in the exudate of V. sativa roots. Relatively small amounts of both LCOs and NodD-activating compounds were found to be required for initiation of nodulation during the first days after inoculation. A strong increase in the amount of NodRlv-V[18:4, Ac] LCOs preceded root infection and nodule primordium formation. In contrast to the situation with non-nodulating rhizobia and nonmitogenic LCOs, the amount of NodD-activating compounds in the culture medium remained small after addition of nodulating rhizobia or mitogenic LCOs. Furthermore, addition of nodulating rhizobia or mitogenic LCOs resulted in nearly complete inhibition of root hair formation and elongation, whereas nonmitogenic LCOs stimulated root hair growth. Retention of NodD-activating compounds in the root may inhibit root hair growth.
23
Downie, J. Allan. "Legume nodulation." Current Biology 24, no. 5 (March 2014): R184—R190. http://dx.doi.org/10.1016/j.cub.2014.01.028.
Full text
24
Li, Xinxin, Huiwen Zhou, Ling Cheng, Niannian Ma, Baofeng Cui, Wenfei Wang, Yongjia Zhong, and Hong Liao. "Shoot-to-root translocated GmNN1/FT2a triggers nodulation and regulates soybean nitrogen nutrition." PLOS Biology 20, no. 8 (August 15, 2022): e3001739. http://dx.doi.org/10.1371/journal.pbio.3001739.
Full textAbstract:
Symbiotic nitrogen fixation (SNF) provides sufficient nitrogen (N) to meet most legume nutrition demands. In return, host plants feed symbionts carbohydrates produced in shoots. However, the molecular dialogue between shoots and symbionts remains largely mysterious. Here, we report the map-based cloning and characterization of a natural variation in GmNN1, the ortholog of Arabidopsis thaliana FLOWERING LOCUS T (FT2a) that simultaneously triggers nodulation in soybean and modulates leaf N nutrition. A 43-bp insertion in the promoter region of GmNN1/FT2a significantly decreased its transcription level and yielded N deficiency phenotypes. Manipulating GmNN1/GmFT2a significantly enhanced soybean nodulation, plant growth, and N nutrition. The near-isogenic lines (NILs) carrying low mRNA abundance alleles of GmNN1/FT2a, along with stable transgenic soybeans with CRISPR/Cas9 knockouts of GmNN1/FT2a, had yellower leaves, lower N concentrations, and fewer nodules than wild-type control plants. Grafting together with split-root experiments demonstrated that only shoot GmNN1/FT2a was responsible for regulating nodulation and thereby N nutrition through shoot-to-root translocation, and this process depends on rhizobial infection. After translocating into roots, shoot-derived GmNN1/FT2a was found to interact with GmNFYA-C (nuclear factor-Y subunit A-C) to activate symbiotic signaling through the previously reported GmNFYA-C-ENOD40 module. In short, the description of the critical soybean nodulation regulatory pathway outlined herein sheds novel insights into the shoot-to-root signaling required for communications between host plants and root nodulating symbionts.
25
Rice, W. A., G. W. Clayton, N. Z. Lupwayi, and P. E. Olsen. "Evaluation of coated seeds as a Rhizobium delivery system for field pea." Canadian Journal of Plant Science 81, no. 2 (April 1, 2001): 247–53. http://dx.doi.org/10.4141/p00-062.
Full textAbstract:
Greenhouse and field experiments were conducted with field peas (Pisum sativum, L.) in soils of pH 4.4 to 6.8 to determine the best rate of inoculation with rhizobium and to evaluate pre-inoculated (coated) seeds as an alternative to the traditional seed inoculation method of using sticking agents. Inoculation rates higher than 105 cells seed–1 were usually required for high nodulation, nitrogen fixation and grain yields. Therefore, Canadian standards, which require that 105 nodulating rhizobia be delivered per seed for large-seed legumes like peas, may need to be increased. Counts of rhizobia on coated seeds were about 3 log units lower than those on freshly inoculated seeds, but coated seeds significantly outperformed standard seed-inoculated seeds in nodulation and crop yield in acid soils (pH 4.4 and 4.7). However, field pea yields were too low to have commercial value at these low pH levels. In soils with higher pH, standard inoculation resulted in greater nodulation and yield, but the differences were not always significant. It is concluded that the use of coated seeds provides a yield advantage for field pea grown on acid soils, but liming would probably be a better option. Use of coated seeds on other soils will depend on the trade-off between the time and money saved in inoculation in order to seed early and a possible reduction in yield due to insufficient numbers of rhizobia being applied. Key words: Nitrogen fixation, nodulation, Pisum sativum, pre-inoculated seeds
26
Athar, Mohammad. "A qualitative study of the nodulating ability of legumes of Pakistan." Acta Societatis Botanicorum Poloniae 66, no. 3-4 (2014): 387–91. http://dx.doi.org/10.5586/asbp.1997.048.
Full textAbstract:
<em>Legume-Rhizobium</em> symbiosis accumulates substantial amounts of mineralizable nitrogen which help in ecological rehabilitation of degraded soils and increase the soil fertility in agricultural ecosystem. Nodulation was studied in 72 legume species from various parts of Pakistan. All the species of <em>Papilionoideae</em> and <em>Mimosoideae</em> were nodulated whereas all the species examined in <em>Caesalpinioideae</em> were non-nodulated. Attempts to elicit nodulation in <em>Caesalpinioid</em> species by rhizobial inoculation were not successful and they were accepted as lacking nodulating ability. Nodulation is reported for the first time in 6 species within 3 genera of <em>Mimosoideae</em> and 9 species within 5 genera of <em>Papilionoideae</em>. Majority of the species were abundantly nodulated under natural soil conditions or when grown in uninoculated garden soil indicating distribution of wide range of naturalized rhizobia. The study shows that the wild legumes hold great promise for inclusion in revegetation of denuded and derelict ecosystems.
27
Graves, William R., Carol M. Foster, Faye M. Rosin, and James A. Schrader. "Two Early Nodulation Genes are not Markers for the Capacity of Leguminous Nursery Crops to Form Root Nodules." Journal of Environmental Horticulture 17, no. 3 (September 1, 1999): 126–29. http://dx.doi.org/10.24266/0738-2898-17.3.126.
Full textAbstract:
Abstract Little is known about mechanisms that permit or prevent formation of root nodules in which nitrogen gas (N2) is fixed by rhizobial bacteria in association with nursery crops in the legume family. We tested the hypothesis that two genes associated with the fixation of N2 could be used as markers of nodulation capacity among legumes because they occur only in species that can form functional nodules. The presence of ENOD2 and ENOD12 was tested in genomic DNA from three non-nodulating legumes [Cercis canadensis L. (eastern redbud), Gleditsia triacanthos L. var. inermis Willd. (thornless honeylocust), Gymnocladus dioicus (L.) K. Koch (Kentucky coffeetree)] and two nodulating legumes [Albizia julibrissin Durazz. (silk-tree), Laburnum alpinum (Mill.) Bercht. & Presl. (Scotch laburnum)]. Southern analyses indicated that ENOD2 is present in thornless honeylocust, Kentucky coffeetree, and Scotch laburnum, and that ENOD12 is present in eastern redbud, thornless honeylocust, and Scotch laburnum. These results diversify the group of nodulating legumes in which ENOD2 and ENOD12 have been found and show these genes also occur in legumes considered incapable of nodulation. We conclude that neither gene can be used to screen existing or new leguminous nursery crops for the capacity to form N2-fixing nodules.
28
Khalifa, F. M. "Effect of nitrogen on nodulation and yield of soya beans under two systems of production in Sudan." Journal of Agricultural Science 108, no. 2 (April 1987): 259–65. http://dx.doi.org/10.1017/s0021859600079247.
Full textAbstract:
SummaryTwo experiments were run over a 3-year period in the central rainlands of Sudan under two systems of production, rainfed and irrigated, to assess the effects of system of production, inoculation and nitrogen fertilizers on plant and nodule development and grain yield of soya beans. Nodulated plants could fix more than 80 kg N/ha under irrigation whereas under rainfed conditions nodulation was neither effective nor efficient. Soya bean was responsive to nitrogen fertilizers under both systems of production giving significant increments in grain yields. Non-nodulating plants with added nitrogen fertilizers produced more total dry matter than nodulating plants during the vegetative phase until flowering time. At 2 weeks after flowering total dry-matter production for both types was equal and from then on to maturity nodulating plants outyielded non-nodulating ones in total dry-matter production. In 1979 and 1980 yield of irrigated nodulating soya-bean grain was 0·53 and 1·54 t/ha higher than rainfed yields whereas the difference in grain yields of the non-nodulating soya beans was 0·21 t/ha and zero during the same two seasons, respectively. There was a contrasting inverse relation between the number of nodules and dry weights under the two systems of production. Fewer and heavier nodules were produced under irrigation whereas under rainfed conditions nodulation was profuse and nodules were light. On the evidence available 1–4 g/m length of the granular form of soil implant inoculant (Nitragin), i.e. 16·6·66.4 kg/ha, is to be recommended for irrigated soya-bean production in Sudan.
29
Sheoran, Anita, A. L. Khurana, and S. S. Dudeja. "Nodulation competitiveness in the Rhizobium-chickpea nodulation variants symbiosis." Microbiological Research 152, no. 4 (December 1997): 407–12. http://dx.doi.org/10.1016/s0944-5013(97)80059-6.
Full text
30
van Velzen, Robin, Rens Holmer, Fengjiao Bu, Luuk Rutten, Arjan van Zeijl, Wei Liu, Luca Santuari, et al. "Comparative genomics of the nonlegume Parasponia reveals insights into evolution of nitrogen-fixing rhizobium symbioses." Proceedings of the National Academy of Sciences 115, no. 20 (May 1, 2018): E4700—E4709. http://dx.doi.org/10.1073/pnas.1721395115.
Full textAbstract:
Nodules harboring nitrogen-fixing rhizobia are a well-known trait of legumes, but nodules also occur in other plant lineages, with rhizobia or the actinomycete Frankia as microsymbiont. It is generally assumed that nodulation evolved independently multiple times. However, molecular-genetic support for this hypothesis is lacking, as the genetic changes underlying nodule evolution remain elusive. We conducted genetic and comparative genomics studies by using Parasponia species (Cannabaceae), the only nonlegumes that can establish nitrogen-fixing nodules with rhizobium. Intergeneric crosses between Parasponia andersonii and its nonnodulating relative Trema tomentosa demonstrated that nodule organogenesis, but not intracellular infection, is a dominant genetic trait. Comparative transcriptomics of P. andersonii and the legume Medicago truncatula revealed utilization of at least 290 orthologous symbiosis genes in nodules. Among these are key genes that, in legumes, are essential for nodulation, including NODULE INCEPTION (NIN) and RHIZOBIUM-DIRECTED POLAR GROWTH (RPG). Comparative analysis of genomes from three Parasponia species and related nonnodulating plant species show evidence of parallel loss in nonnodulating species of putative orthologs of NIN, RPG, and NOD FACTOR PERCEPTION. Parallel loss of these symbiosis genes indicates that these nonnodulating lineages lost the potential to nodulate. Taken together, our results challenge the view that nodulation evolved in parallel and raises the possibility that nodulation originated ∼100 Mya in a common ancestor of all nodulating plant species, but was subsequently lost in many descendant lineages. This will have profound implications for translational approaches aimed at engineering nitrogen-fixing nodules in crop plants.
31
Narożna, Dorota, Krzysztof Pudełko, Joanna Króliczak, Barbara Golińska, Masayuki Sugawara, Cezary J. Mądrzak, and Michael J. Sadowsky. "Survival and Competitiveness of Bradyrhizobium japonicum Strains 20 Years after Introduction into Field Locations in Poland." Applied and Environmental Microbiology 81, no. 16 (June 5, 2015): 5552–59. http://dx.doi.org/10.1128/aem.01399-15.
Full textAbstract:
ABSTRACTIt was previously demonstrated that there are no indigenous strains ofBradyrhizobium japonicumforming nitrogen-fixing root nodule symbioses with soybean plants in arable field soils in Poland. However, bacteria currently classified within this species are present (together withBradyrhizobium canariense) as indigenous populations of strains specific for nodulation of legumes in the Genisteae tribe. These rhizobia, infecting legumes such as lupins, are well established in Polish soils. The studies described here were based on soybean nodulation field experiments, established at the Poznań University of Life Sciences Experiment Station in Gorzyń, Poland, and initiated in the spring of 1994. Long-term research was then conducted in order to study the relation betweenB. japonicumUSDA 110 and USDA 123, introduced together into the same location, where no soybean rhizobia were earlier detected, and nodulation and competitive success were followed over time. Here we report the extra-long-term saprophytic survival ofB. japonicumstrains nodulating soybeans that were introduced as inoculants 20 years earlier and where soybeans were not grown for the next 17 years. The strains remained viable and symbiotically competent, and molecular and immunochemical methods showed that the strains were undistinguishable from the original inoculum strains USDA 110 and USDA 123. We also show that the strains had balanced numbers and their mobility in soil was low. To our knowledge, this is the first report showing the extra-long-term persistence of soybean-nodulating strains introduced into Polish soils and the first analyzing the long-term competitive relations of USDA 110 and USDA 123 after the two strains, neither of which was native, were introduced into the environment almost 2 decades ago.
32
Sugawara, Masayuki, and Michael J. Sadowsky. "Enhanced Nodulation and Nodule Development by nolR Mutants of Sinorhizobium medicae on Specific Medicago Host Genotypes." Molecular Plant-Microbe Interactions® 27, no. 4 (April 2014): 328–35. http://dx.doi.org/10.1094/mpmi-10-13-0312-r.
Full textAbstract:
The nolR gene encodes a negatively acting, transcriptional regulatory protein of core Nod-factor biosynthetic genes in the sinorhizobia. Although previous reports showed that nolR modulates Nod-factor production and enhances nodulation speed of Sinorhizobium meliloti on alfalfa, there have been no reports for the symbiotic function of this gene in the S. medicae–Medicago truncatula symbiosis. Here, we constructed an nolR mutant of S. medicae WSM419 and evaluated mutant and wild-type strains for their nodulation ability, competitiveness, host specificity, and density-dependent nodulation phenotypes. When the mutant was inoculated at low and medium population densities, it showed enhanced nodule formation during the initial stages of nodulation. Results of quantitative competitive nodulation assays indicated that an nolR mutant had 2.3-fold greater competitiveness for nodulation on M. truncatula ‘A17’ than did the wild-type strain. Moreover, the nodulation phenotype of the nolR mutant differed among Medicago genotypes and showed significantly enhanced nodule development on M. tricycla. Taken together, these results indicated that mutation of nolR in S. medicae positively influenced nodule initiation, competitive nodulation, and nodule development at later nodulation stages. This may allow nolR mutants of S. medicae to have a selective advantage under field conditions.
33
van Brussel, Anton A. N., Teun Tak, Kees J. M. Boot, and Jan W. Kijne. "Autoregulation of Root Nodule Formation: Signals of Both Symbiotic Partners Studied in a Split-Root System of Vicia sativa subsp. nigra." Molecular Plant-Microbe Interactions® 15, no. 4 (April 2002): 341–49. http://dx.doi.org/10.1094/mpmi.2002.15.4.341.
Full textAbstract:
Inhibition of root nodule formation on leguminous plants by already induced or existing root nodules is called autoregulation of root nodule formation (AUT). Optimal conditions for AUT were determined using a split-root technique newly developed for Vicia sativa subsp. nigra. Infection of a root A with nodulating Rhizobium leguminosarum bv. viciae bacteria systemically inhibited nodulation of a spatially separated root B inoculated 2 days later with the same bacteria. This treatment gives complete AUT (total absence of nodules on root B). Only partial AUT of root B was obtained by incubation of root A with mitogenic nodulation (Nod) factors or with a noninfective strain producing normal mitogenic Nod factors. Nonmitogenic Nod factors did not evoke AUT. We identified two systemic plant signals induced by Rhizobium bacteria. Signal 1 (at weak buffering) was correlated with sink formation in root A and induced acidification of B-root medium. This signal is induced by treatment of root A with (i) nodulating rhizobia, (ii) mitogenic Nod factors, (iii) nonmitogenic Nod factors, or (iv) the cytokinin zeatin. Signal 2 (at strong buffering) could only be evoked by treatment with nodulating rhizobia or with mitogenic Nod factors. Most probably, this signal represents the specific AUT signal. Induction of complete AUT appears to require actively dividing nodule cells in nodule primordia, nodule meristems, or both of root A.
34
Singh, Inderpal, and M. H. Ahmad. "Competitive interaction between non-nodulating and nodulating strains for nodulation of cowpea (Vigna unguiculata)." FEMS Microbiology Letters 81, no. 2 (June 1991): 157–60. http://dx.doi.org/10.1111/j.1574-6968.1991.tb04739.x.
Full text
35
Essomba, N. B., T. A. Coffelt, W. D. Branch, and S. W. Van Scoyoc. "Inheritance of Stem Color and Non-Nodulation in Peanut1." Peanut Science 18, no. 2 (July 1, 1991): 126–31. http://dx.doi.org/10.3146/i0095-3679-18-2-16.
Full textAbstract:
Abstract Extra-nuclear factors have been reported in peanut (Arachts hypogaea L.) for many traits including growth habit, stipule shape, pod constriction, resistance to leafspot disease, and calcium concentration. However, the role of extra-nuclear factors with the inheritance of many other peanut traits remains to be ascertained. The objective of this study was to determine the inheritance of stem color and non-nodulation, and whether their inheritance is influenced by extra-nuclear factors. The study was conducted on the F1 and F2 progenies obtained from a modified diallel design with two A. hypogaea genotypes, Argentine and T2442, and one A. monticola Krap. et Rig. genotype, as parents. Two plant parts (main and lateral stems) were visually classified for stem color (purple, mixed, or green). Plants graded as green-green, mixed-green, or mixed-mixed were grouped as green and all others as purple for genetic analyses. Plants were classified as non-nodulatingif symptoms of N deficiency were observed. Distribution of data for stem color was bimodal, supporting the grouping of data into two phenotypic classes (green and purple). The F2 generation fit ratios of 1 green: 3 purple, 6 green: 10 purple, 9 green: 7 purple, 11 green: 5 purple, or 15 green: 1 purple depending on the parents. These results indicate that a) stem color may be determined by two sets of genes of which the first one may be responsible for purple pigmentation and the second one for green pigmentation, b) these two gene sets, comprising, respectively, one and two loci for purple and green pigmentations, may have epistatic relationships, c) extra-nuclear factors may function as alleles to nuclear genes responsible for stem color, and d) extra-nuclear factors may induce or modify relationships between traits when they interfere with nuclear genes determining these traits. In the F2 of crosses with T2442 as one parent and either A. monticola or Argentine as the other, ratios of 57 nodulating: 7 non-nodulatmg plants and 54 nodulating: 10 non-nodulating plants were observed. These results indicate that a) non-nodulation trait may be determined by three independent non-duplicate genes and b) at least two homozygous recessive loci are required in a genotype for non-nodulation. The following genotypes are proposed for the three parents: A. monticola: Ps1sPs 1gs1gs1 gs2gs2; N3N3 N4N4 N5N5 Argentine: gs1gs1 Gs1Gs1 gs2gs2; N3N3 N4N4 N5N5 T2442: ps1ps1 gs1gs1 Gs2Gs2; n3n3 n4n4 n5n5
36
Srinivasan, M., F. B. Holl, and D. J. Petersen. "Nodulation ofPhaseolus vulgarisbyRhizobium etliis enhanced by the presence ofBacillus." Canadian Journal of Microbiology 43, no. 1 (January 1, 1997): 1–8. http://dx.doi.org/10.1139/m97-001.
Full textAbstract:
The ability of Bacillus spp. to alter the nodulation of Phaseolus vulgaris by Rhizobium etli was assessed. The simultaneous presence of both Rhizobium etli TAL 182 and Bacillus megaterium S49 on plant roots during the early stages of plant growth was necessary for enhanced nodulation of Phaseolus vulgaris by the Rhizobium microsymbiont. Coinoculation with both bacterial species also facilitated heterologous nodulation of Rhizobium TAL 182 on Phaseolus acutifolius. These results are consistent with earlier reports of increased root hair proliferation and lateral root formation in response to coinoculation. Split-root experiments revealed that coinoculation partially suppressed host-controlled regulation of nodulation, implicating a plant interaction with the two bacterial species. Changes to the nodulation potential of R. etli due to coinoculation with Bacillus spp. demonstrate the potential for root-associated organisms other than rhizobia to alter the dynamics of the legume–Rhizobium symbiosis.Key words: Bacillus, nodulation enhancement, heterologous nodulation.
37
Webb, Judith R., and Janet I. Sprent. "Nodulation in Legumes." Kew Bulletin 57, no. 3 (2002): 634. http://dx.doi.org/10.2307/4110991.
Full text
38
BULAWA, CHRISTINE E., and WILMA WASCO. "Chitin and nodulation." Nature 353, no. 6346 (October 1991): 710. http://dx.doi.org/10.1038/353710b0.
Full text
39
Gough, N. R. "Systemic Nodulation Regulation." Science Signaling 3, no. 122 (May 18, 2010): ec150-ec150. http://dx.doi.org/10.1126/scisignal.3122ec150.
Full text
40
Xie, Z. P., C. Staehelin, H. Vierheilig, A. Wiemken, S. Jabbouri, W. J. Broughton, R. Vogeli-Lange, and T. Boller. "Rhizobial Nodulation Factors Stimulate Mycorrhizal Colonization of Nodulating and Nonnodulating Soybeans." Plant Physiology 108, no. 4 (August 1, 1995): 1519–25. http://dx.doi.org/10.1104/pp.108.4.1519.
Full text
41
Liu, Yuan Hui, Yin Shan Jiao, Li Xue Liu, Dan Wang, Chang Fu Tian, En Tao Wang, Lei Wang, et al. "Nonspecific Symbiosis Between Sophora flavescens and Different Rhizobia." Molecular Plant-Microbe Interactions® 31, no. 2 (February 2018): 224–32. http://dx.doi.org/10.1094/mpmi-05-17-0117-r.
Full textAbstract:
We explored the genetic basis of the promiscuous symbiosis of Sophora flavescens with diverse rhizobia. To determine the impact of Nod factors (NFs) on the symbiosis of S. flavescens, nodulation-related gene mutants of representative rhizobial strains were generated. Strains with mutations in common nodulation genes (nodC, nodM, and nodE) failed to nodulate S. flavescens, indicating that the promiscuous nodulation of this plant is strictly dependent on the basic NF structure. Mutations of the NF decoration genes nodH, nodS, nodZ, and noeI did not affect the nodulation of S. flavescens, but these mutations affected the nitrogen-fixation efficiency of nodules. Wild-type Bradyrhizobium diazoefficiens USDA110 cannot nodulate S. flavescens, but we obtained 14 Tn5 mutants of B. diazoefficiens that nodulated S. flavescens. This suggested that the mutations had disrupted a negative regulator that prevents nodulation of S. flavescens, leading to nonspecific nodulation. For Ensifer fredii CCBAU 45436 mutants, the minimal NF structure was sufficient for nodulation of soybean and S. flavescens. In summary, the mechanism of promiscuous symbiosis of S. flavescens with rhizobia might be related to its nonspecific recognition of NF structures, and the host specificity of rhizobia may also be controlled by currently unknown nodulation-related genes.
42
Sharma, P. K., F. C. Garg, and K. Lakshminarayana. "Induction of stem nodules in pigeonpea (Cajanus cajan L. Millsp.)." Journal of Agricultural Science 110, no. 2 (April 1988): 375–76. http://dx.doi.org/10.1017/s0021859600081417.
Full textAbstract:
Legumes like Aschynomene, Neptunia and Sesbania possess nodules on their stems in addition to those on the roots (Barrios & Gonzelez, 1971; Dreyfus & Dommergues, 1981) and have the ability to grow under water. The most distinctive characteristic of all stem nodulating legumes in the presence of predetermined nodulation sites on the stem, the formation of which is independent of Rhizobiwm infection (Arora, 1954; Subba Rao, Tilak & Singh, 1980).
43
Hogg, Bridget, Andrea E. Davies, Karen E. Wilson, Ton Bisseling, and J. Allan Downie. "Competitive Nodulation Blocking of cv. Afghanistan Pea Is Related to High Levels of Nodulation Factors Made by Some Strains of Rhizobium leguminosarum bv. viciae." Molecular Plant-Microbe Interactions® 15, no. 1 (January 2002): 60–68. http://dx.doi.org/10.1094/mpmi.2002.15.1.60.
Full textAbstract:
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.
44
Nasrollahi, Vida, Ze-Chun Yuan, Susanne E. Kohalmi, and Abdelali Hannoufa. "SPL12 Regulates AGL6 and AGL21 to Modulate Nodulation and Root Regeneration under Osmotic Stress and Nitrate Sufficiency Conditions in Medicago sativa." Plants 11, no. 22 (November 13, 2022): 3071. http://dx.doi.org/10.3390/plants11223071.
Full textAbstract:
The highly conserved plant microRNA, miR156, affects root architecture, nodulation, symbiotic nitrogen fixation, and stress response. In Medicago sativa, transcripts of eleven SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE, SPLs, including SPL12, are targeted for cleavage by miR156. Our previous research revealed the role of SPL12 and its target gene, AGL6, in nodulation in alfalfa. Here, we investigated the involvement of SPL12, AGL6 and AGL21 in nodulation under osmotic stress and different nitrate availability conditions. Characterization of phenotypic and molecular parameters revealed that the SPL12/AGL6 module plays a negative role in maintaining nodulation under osmotic stress. While there was a decrease in the nodule numbers in WT plants under osmotic stress, the SPL12-RNAi and AGL6-RNAi genotypes maintained nodulation under osmotic stress. Moreover, the results showed that SPL12 regulates nodulation under a high concentration of nitrate by silencing AGL21. AGL21 transcript levels were increased under nitrate treatment in WT plants, but SPL12 was not affected throughout the treatment period. Given that AGL21 was significantly upregulated in SPL12-RNAi plants, we conclude that SPL12 may be involved in regulating nitrate inhibition of nodulation in alfalfa by targeting AGL21. Taken together, our results suggest that SPL12, AGL6, and AGL21 form a genetic module that regulates nodulation in alfalfa under osmotic stress and in response to nitrate.
45
Lemaire, Benny, Samson B. M. Chimphango, Charles Stirton, Suhail Rafudeen, Olivier Honnay, Erik Smets, Wen-Ming Chen, Janet Sprent, Euan K. James, and A. Muthama Muasya. "Biogeographical Patterns of Legume-Nodulating Burkholderia spp.: from African Fynbos to Continental Scales." Applied and Environmental Microbiology 82, no. 17 (June 17, 2016): 5099–115. http://dx.doi.org/10.1128/aem.00591-16.
Full textAbstract:
ABSTRACTRhizobia of the genusBurkholderiahave large-scale distribution ranges and are usually associated with South African papilionoid and South American mimosoid legumes, yet little is known about their genetic structuring at either local or global geographic scales. To understand variation at different spatial scales, from individual legumes in the fynbos (South Africa) to a global context, we analyzed chromosomal (16S rRNA,recA) and symbiosis (nifH,nodA,nodC) gene sequences. We showed that the global diversity of nodulation genes is generally grouped according to the South African papilionoid or South American mimosoid subfamilies, whereas chromosomal sequence data were unrelated to biogeography. While nodulation genes are structured on a continental scale, a geographic or host-specific distribution pattern was not detected in the fynbos region. In host range experiments, symbiotic promiscuity ofBurkholderiatuberumSTM678TandB.phymatumSTM815Twas discovered in selected fynbos species. Finally, a greenhouse experiment was undertaken to assess the ability of mimosoid (Mimosapudica) and papilionoid (Dipogonlignosus,Indigoferafilifolia,Macroptiliumatropurpureum, andPodalyriacalyptrata) species to nodulate in South African (fynbos) and Malawian (savanna) soils. While theBurkholderia-philous fynbos legumes (D.lignosus,I.filifolia, andP.calyptrata) nodulated only in their native soils, the invasive neotropical speciesM.pudicadid not develop nodules in the African soils. The fynbos soil, notably rich inBurkholderia, seems to retain nodulation genes compatible with the local papilionoid legume flora but is incapable of nodulating mimosoid legumes that have their center of diversity in South America.IMPORTANCEThis study is the most comprehensive phylogenetic assessment of root-nodulatingBurkholderiaand investigated biogeographic and host-related patterns of the legume-rhizobial symbiosis in the South African fynbos biome, as well as at global scales, including native species from the South American Caatinga and Cerrado biomes. While a global investigation of the rhizobial diversity revealed distinct nodulation and nitrogen fixation genes among South African and South American legumes, regionally distributed species in the Cape region were unrelated to geographic and host factors.
46
Zhang, Xue-Xian, Sarah L. Turner, Xian-Wu Guo, Hui-Jun Yang, Fr�d�ric Debell�, Guo-Ping Yang, Jean D�nari�, J. Peter W. Young, and Fu-Di Li. "The Common Nodulation Genes of Astragalus sinicus Rhizobia Are Conserved despite Chromosomal Diversity." Applied and Environmental Microbiology 66, no. 7 (July 1, 2000): 2988–95. http://dx.doi.org/10.1128/aem.66.7.2988-2995.2000.
Full textAbstract:
ABSTRACT The nodulation genes of Mesorhizobium sp. (Astragalus sinicus) strain 7653R were cloned by functional complementation of Sinorhizobium meliloti nod mutants. The common nod genes, nodD, nodA, andnodBC, were identified by heterologous hybridization and sequence analysis. The nodA gene was found to be separated from nodBC by approximately 22 kb and was divergently transcribed. The 2.0-kb nodDBC region was amplified by PCR from 24 rhizobial strains nodulating A. sinicus, which represented different chromosomal genotypes and geographic origins. No polymorphism was found in the size of PCR products, suggesting that the separation of nodA from nodBC is a common feature of A. sinicus rhizobia. Sequence analysis of the PCR-amplified nodA gene indicated that seven strains representing different 16S and 23S ribosomal DNA genotypes had identical nodA sequences. These data indicate that, whereas microsymbionts of A. sinicus exhibit chromosomal diversity, their nodulation genes are conserved, supporting the hypothesis of horizontal transfer of nod genes among diverse recipient bacteria.
47
Calica, Phoebe N. "Nodulation and Nitrogen Fixation of Pongamia pinnata." Journal of Tropical Crop Science 4, no. 1 (February 1, 2017): 1–12. http://dx.doi.org/10.29244/jtcs.4.1.1-12.
Full textAbstract:
Nitrogen is one of the most important nutrients required by plants as a major component of all nucleic acids and proteins such as enzymes which control and enable their growth and reproduction. While much research has been conducted on the legume tree Pongamia (a candidate source for renewable biofuel), there is only a handful of studies on the mechanisms and regulation of nitrogen fixation, which is considered as one of the most important domestication traits that needs to be investigated. Steps to optimize the symbiotic nitrogen fixation of Pongamia is, firstly, to select the best rhizobial isolates as inoculum among the naturally-occurring pool of bacteria in soils across Queensland. There have been reports on rhizobia nodulating Pongamia isolated from Western Australia and India but not in Queensland, Australia. This study is the first to report such rhizobia isolates that nodulated Pongamia. Secondly, is to establish efficient nodulation by studying the factors such as nitrate and salinity. The published literature has provided extensive details on the effects of these factors in nodulation and their mechanisms in various legumes. However, only one preliminary study was published from our laboratory; the present study is the in-depth continuation of that effort. Lastly, nitrogen fixation in Pongamia must be assessed to determine if fixed nitrogen is sufficient to support its growth and reproduction. Acetylene reduction assay is the simplest and most common method of assessing fixed nitrogen but in this research, different methods were explored in order to compare both qualitative and quantitative results. This review summarises the current knowledge related to Pongamia, rhizobia, nodulation and nitrogen fixation.
48
Ferrey, M. L., P. H. Graham, and M. P. Russelle. "Nodulation efficiency of Bradyrhizobium japonicum strains with genotypes of soybean varying in the ability to restrict nodulation." Canadian Journal of Microbiology 40, no. 6 (June 1, 1994): 456–60. http://dx.doi.org/10.1139/m94-074.
Full textAbstract:
Competition from existing soil rhizobia has limited the benefits from nitrogen fixation for soybean grown in the American Midwest. A strategy being considered to overcome this problem is the use of varieties that are restricted in nodulation with soil strains, but nodulate normally with inoculant bradyrhizobia. In this study we examine the efficiency in nodulation of strains of Bradyrhizobium japonicum that have been reported as restricted in nodulation with specific genotypes of soybean, using a root-tip marking procedure in growth pouches. When B. japonicum USDA110 was applied to the soybean cultivars Hardee and Fiskeby V at the rate of 3.50 × 104 cells/pouch, more than 75% of the plants were nodulated above the root-tip mark, and average uppermost nodule position was above the root-tip mark. By contrast, when this strain was applied in similar concentration to the soybean cultivar Peking, few plants developed nodules above the root-tip mark, and the average position of the uppermost taproot nodule was nearly 30 mm below this mark. Nodulation was improved at higher rates of inoculation, but even when 3.50 × 106 cells were applied to each pouch, less than 50% of the plants were nodulated above the root-tip mark. Bradyrhizobium japonicum strain CB1809 (=USDA136) was also efficient in nodulation with cv. Fiskeby V, but with cv. Hardee, less than 65% of plants were nodulated above the root-tip mark, irrespective of inoculation rate. Because restriction of nodulation with the strains initially tested was not absolute, we examined the patterns of nodulation obtained following the inoculation of two restriction hosts, Peking and PI371607. In pure culture, serogroup USDA110 strains failed to induce significant taproot nodulation of cv. Peking in Leonard jars, but did induce lateral root nodulation. However, in a glasshouse experiment contrasting soil- and seed-applied inoculant, lateral-root nodulation of the restriction host PI371607 by USDA123 was not significant.Key words: Glycine max, competition, restriction, nodulation.
49
Wahyuni, WS, and JW Randles. "Inoculation with root nodulating bacteria reduces the susceptibility of Medicago truncatula and Lupinus angustifolius to cucumber mosaic virus (CMV) and addition of nitrate partially reverses the effect." Australian Journal of Agricultural Research 44, no. 8 (1993): 1917. http://dx.doi.org/10.1071/ar9931917.
Full textAbstract:
The susceptibility of Medicago truncatula ssp. truncatula (barrel medic) cv. Jemalong and Lupinus angustifolius (lupin) cv. Illyarrie and Gungurru to cucumber mosaic virus (CMV) was reduced by prior inoculation of seedlings with commercial strains of root nodulating bacteria (Rhizobium or Bradyrhizobium, respectively). This effect was observed both with strains of CMV originating from legumes and with strains originating from non-legumes. The virus content of the nodulated plants which were successfully inoculated was not markedly affected by nodulation, indicating that nodulation affected susceptibility to inoculation, and not the ability of CMV to replicate. In lupins, the reduction in susceptibility followed mechanical and graft inoculation of plants with virus. The effect was first noted at about the time that acetylene reduction activity (ARA) was first detected and just before nodules appeared. Virus-infected lupins showed a delay in the development of nodules and a reduced ARA, compared with uninfected plants, indicating that there was a two-way interaction between the virus and Bradyrhizobium. Different growth conditions did not affect the ARA values, the severity of symptoms or the susceptibility of lupin to CMV. A minimum level of nitrate was required for medic growth both with and without the root nodulating bacteria. The addition of higher levels of nitrate to the nutrient solution partially reversed the effect of the nodulating bacteria, in that it increased the susceptibility of the plants. Medics not inoculated with Rhizobium and supplied with a high concentration of nitrate were the most susceptible to CMV. In a test to compare competent with incompetent bacteria, Rhizobium strain 1021 (which fixes N2) and its mutant, Rm 1491 (which does not fix N2), did not differ in their effect on susceptibility. Aggregates of virus particles and crystals of virus were found in nodule cells of medic plants, but virus particles and bacteroids were not found in the same cell. Individual and aggregated virus particles were commonly located along the cell wall of cells free of bacteroids. It is concluded that infection by root nodulating bacteria and external nitrogen supplementation have opposite effects on the susceptibility of barrel medic and lupin to CMV, and that CMV, in turn, reduces the effectiveness of the symbiosis between these bacteria and their host. Nodulation has little effect on virus replication, and both virus and bacteroids occur in the same nodule tissue.
50
van Spronsen, Paulina C., Mette Grønlund, Cristina Pacios Bras, Herman P. Spaink, and Jan W. Kijne. "Cell Biological Changes of Outer Cortical Root Cells in Early Determinate Nodulation." Molecular Plant-Microbe Interactions® 14, no. 7 (July 2001): 839–47. http://dx.doi.org/10.1094/mpmi.2001.14.7.839.
Full textAbstract:
In the symbiosis of leguminous plants and Rhizobium bacteria, nodule primordia develop in the root cortex. This can be either in the inner cortex (indeterminate-type of nodulation) or outer cortex (determinate-type of nodulation), depending upon the host plant. We studied and compared early nodulation stages in common bean (Phaseolus vulgaris) and Lotus japonicus, both known as determinate-type nodulation plants. Special attention was paid to the occurrence of cytoplasmic bridges, the influence of rhizobial Nod factors (lipochitin oligosaccharides [LCOs]) on this phenomenon, and sensitivity of the nodulation process to ethylene. Our results show that i) both plant species form initially broad, matrix-rich infection threads; ii) cytoplasmic bridges occur in L. japonicus but not in bean; iii) formation of these bridges is induced by rhizobial LCOs; iv) formation of primordia starts in L. japonicus in the middle root cortex and in bean in the outer root cortex; and v) in the presence of the ethylenebiosynthesis inhibitor aminoethoxyvinylglycine (AVG), nodulation of L. japonicus is stimulated when the roots are grown in the light, which is consistent with the role of cytoplasmic bridges during nodulation of L. japonicus.