Abstract
In greenhouse studies, the symbiotic properties of a prototrophic revertant (TA11 NOD+) of a nodulation defective tryptophan auxotroph of Bradyrhizobium japonicum were compared with those of the normally nodulating wild-type strain, B. japonicum I-110 ARS. Strain I-110 ARS was the parent of auxotrophic mutant TA11. Plants inoculated with TA11 NOD+ contained significantly more nitrogen per plant than did plants inoculated with wild-type bacteria (275.9 ± 35 versus 184 ± 18 mg). Also, plants that received the revertant were larger, averaging 8.4 ± 0.9 g (dry weight) versus 6.4 ± 0.6 g for those that received the wild-type bacterial strain. Additionally, plants that received the NOD+ strain had 56% more nodules and 41% more nodule mass than did control plants. With both inocula, average nodule size and amount of nitrogen fixed per gram of nodule were about the same. These data indicated that the improvement in nitrogen fixation observed with the TA11 NOD+ resulted from an increase in the overall nodule number. The physiological basis for this increase in nodulation is not known, but enhanced tryptophan catabolism does not appear to be involved.
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Selected References
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- Cole M. A., Elkan G. H. Transmissible resistance to penicillin G, neomycin, and chloramphenicol in Rhizobium japonicum. Antimicrob Agents Chemother. 1973 Sep;4(3):248–253. doi: 10.1128/aac.4.3.248. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hunter W. J. Influence of 5-Methyltryptophan-Resistant Bradyrhizobium japonicum on Soybean Root Nodule Indole-3-Acetic Acid Content. Appl Environ Microbiol. 1987 May;53(5):1051–1055. doi: 10.1128/aem.53.5.1051-1055.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuykendall L. D., Elkan G. H. Rhizobium japonicum derivatives differing in nitrogen-fixing efficiency and carbohydrate utilization. Appl Environ Microbiol. 1976 Oct;32(4):511–519. doi: 10.1128/aem.32.4.511-519.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuykendall L. D., Weber D. F. Genetically marked Rhizobium identifiable as inoculum strain in nodules of soybean plants grown in fields populated with Rhizobium japonicum. Appl Environ Microbiol. 1978 Dec;36(6):915–919. doi: 10.1128/aem.36.6.915-919.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wells S. E., Kuykendall L. D. Tryptophan auxotrophs of Rhizobium japonicum. J Bacteriol. 1983 Dec;156(3):1356–1358. doi: 10.1128/jb.156.3.1356-1358.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]