Abstract
When interactions between diazotrophic bacteria and non-legume plants are studied within the context of trying to extend biological nitrogen fixation to non-legume crops, an important first step is to establish reproducible internal colonization at high frequency of these plants. Using Azorhizobium caulinodans ORS571 (which induces stem and root nodules on the tropical legume Sesbania rostrata), tagged with a constitutively expressed lacZ reporter gene, we have studied the possibilities of internal colonization of the root system of the model dicot Arabidopsis thaliana. ORS571 was found to be able to enter A. thaliana roots after first colonizing lateral root cracks (LRCs), at the points of emergence of lateral roots. Cytological studies showed that after LRC colonization, bacteria moved into the intercellular space between the cortical and endodermal cell layers of roots. In our experimental conditions, this LRC and intercellular colonization are reproducible and occur at high frequency, although the level of colonization at each site is low. The flavonoids naringenin and daidzein, at low concentrations, were found to significantly stimulate (at the p=0.01 level) the frequency of LRC and intercellular colonization of A. thaliana roots by A. caulinodans. The role in colonization of the structural nodABC genes, as well as the regulatory gene nodD, was studied and it was found that both colonization and flavonoid stimulation of colonization are nod gene-independent. These systems should now enable the various genetic and physiological factors which are limiting both for rhizobial colonization and for endophytic nitrogen fixation in non-legumes, to be investigated. In particular, the use of A. thaliana, which has many advantages over other plants for molecular genetic studies, to study interactions between diazotrophic bacteria and non-legume dicots, should provide the means of identifying and understanding the mechanisms by which plant genes are involved in these interactions.
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References
Boddey R M, de Oliveira O C, Urquiaga S, Reis V M, de Oliveira F L, Baldani V L D and Döbereiner J 1995 Biological nitrogen fixation associated with sugarcane and rice: contributions and prospects for improvement. Plant Soil 174, 195–209.
Boivin C, Camut S, Malpica C A, Truchet G and Rosenberg C 1990 Rhizobium meliloti genes encoding catabolism of trigonellin are induced under symbiotic conditions. Plant Cell 2, 1157–1170
Cocking E C, Webster G, Batchelor C A and Davey M R 1994 Nodulation of non-legume crops. A new look. Agro-Food-Industry Hi-Tech. January/Febuary, 21–24.
Cocking E C, Davey M R, Kothari S L, Srivastava J S, Jing Y, Ridge R W and Rolfe B G 1992 Altering the specificity control of the interaction between rhizobia and plants. Symbiosis 14, 123–130.
de Bruijn F J, Ying Y and Dazzo F B 1995 Potential and pitfalls of trying to extend symbiotic interactions of nitrogen-fixing organisms to presently non-nodulated plants, such as rice. Plant Soil 174, 225–240.
de Bruijn F 1989 The unusual symbiosis between the diazotrophic stem-nodulating bacterium Azorhizobium caulinodans ORS571 and its host, the tropical legume Sesbania rostrata. In Plant-Microbe Interactions: Molecular and Genetic Perspectives. Vol. 3. Ed. T Kosuge and E W Nester pp 457–504 McGraw-Hill Publishing Company.
Dénarié J, Debellé F and Promé J C 1996 Rhizobium lipochitooligosaccharide nodulation factors: signaling molecules mediating recognition and morphogenesis. Annu. Rev. Biochem. 65, 503–535.
Dénarié J and Cullimore J 1993 Lipo-chitooligosaccharide nodulation factors: a new class of signaling molecules mediating recognition and morphogenesis. Cell 74, 951–954.
Dénarié J, Debellé F and Rosenberg C 1992 Signaling and host range variation in nodulation. Annu. Rev. Microbiol. 46, 497–531.
Dolan L, Janmaat K, Linstead P, Poethig S, Roberts K and Scheres B 1993 Cellular organisation of the Arabidopsis thaliana root. Development 119, 71–84.
Donald R G K and Ludwig R A 1984 Rhizobium sp. strain ORS571 ammonium assimilation and nitrogen fixation. J. Bacteriol. 158, 1144–1151.
Geelen D, Mergaert P, Gememia R A, Goormachtig S, Van Montagu M and Holsters M 1993 Identification of nodSUIJ genes in Nod locus 1 of Azorhizobium caulinodans: evidence that nodS encodes a methyltransferase involved in Nod factor modification. Mol. Microbiol. 9, 145–154.
Geremia R A, Mergaert P, Geelen D, Van Montagu M and Holsters M 1994 The NodC protein of Azorhizobium caulinodans is an Nacetylglucosaminyltransferase. Proc. Natl. Acad. Sci. USA. 91, 2669–2673.
Goethals K, Van Den Eede G, Van Montagu M and Holsters M 1990 Identification and characterization of a functional nodD gene in Azorhizobium caulinodans ORS571. J. Bacteriol. 172, 2658–2666.
Goethals K, Gao M, Tomekpe K, Van Montagu M. and Holsters M 1989 Common nodABC genes in Nod locus 1 of Azorhizobium caulinodans: nucleotide sequence and plant-inducible expression. Mol. Gen. Genet. 219, 289–298.
Gough C, Webster G, Vasse J, Galera C, Batchelor C, O'Callaghan K, Davey M, Kothari S, Dénarié J and Cocking E C 1996 Specific flavonoids stimulate intercellular colonization of non-legumes by Azorhizobium caulinodans. In Biology of Plant-Microbe Interactions. Eds. G Stacey, B Mullin and P M Gresshoff. pp 409–415. Int. Soc. for Molec Plant-Microbe Interact., Minnesota.
Hartwig U A, Joseph C M and Phillips D A 1991 Flavonoids released naturally from alfalfa seeds enhance growth rate of Rhizobium meliloti. Plant Physiol. 95, 797–803.
James E K, Reis V M, Olivares F L, Baldani J I and Döbereiner J 1994 Infection of sugarcane by the nitrogen-fixing bacterium Acetobacter diazotrophicus. J. Exp. Bot. 45, 757–766.
Ladha J K and Reddy P M 1995 Extension of nitrogen fixation to rice-necessity and possibilities. GeoJournal 35, 363–372.
Leong S A Williams P H and Ditta G S 1985 Analysis of the 5’ regulatory region of the gene for δ-aminolevulinic acid synthetase of Rhizobium meliloti. Nucl. Acids Res. 13, 5965–5976.
Ndoye I, De Billy F, Vasse J, Dreyfus B and Truchet G 1994 Root nodulation of Sesbania rostrata. J. Bacteriol. 176, 1060–1068.
Peters N Kand Verma D P S 1990 Phenolic compounds as regulators of gene expression in plant-microbe interactions. Mol. Plant-Microbe Interact. 3, 4–8.
Pawlowski K, Ratet P, Schell J and de Bruijn F J 1987 Cloning and characterization of nifA and ntrC genes of the stem nodulating bacterium ORS571, the nitrogen fixing symbiont of Sesbania rostrata: regulation of nitrogen fixation (nif) genes in the free living versus symbiotic state. Mol. Gen. Genet. 206, 207–219.
Sadowsky M J, Olson E R, Foster V E, Kosslak R M and Verma D P S 1988 Two host-inducible genes of Rhizobium fredii and characterization of the inducing compound. J. Bacteriol. 170, 171–178.
Snedecor G and Cochran W 1980 Statistical Methods. (Ames, IA, Iowa State University Press).
Sprent J I, Sutherland J M and de Faria S M 1987 Some aspects of the biology of nitrogen-fixing organisms. Phil. Trans. R. Soc. Lond. B 317, 111–129.
Trinick M J 1973 Symbiosis between Rhizobium and the nonlegume, Trema aspera. Nature 244, 459–460.
Vasse J, Frey P and Trigalet A 1995 Microscopic studies of intercellular infection and protoxylem invasion of tomato roots by Pseudomonas solanacearum. Mol. Plant-Microbe Interact. 8, 241– 251.
Webster G, Davey M R and Cocking E C 1995 Parasponia with rhizobia: a neglected non-legume nitrogen-fixing symbiosis. AgBiotech News Info. 7, 119N–124N.
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Gough, C., Vasse, J., Galera, C. et al. Interactions between bacterial diazotrophs and non-legume dicots: Arabidopsis thaliana as a model plant. Plant and Soil 194, 123–130 (1997). https://doi.org/10.1023/A:1004235919993
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DOI: https://doi.org/10.1023/A:1004235919993