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Updated: Jul 8, 2026

Plant Promoter Analysis: Identification and Characterization of Root Nodule Specific Promoter in the Common Bean
Published on: December 23, 2017
Split-root study of autoregulation of nodulation in the model legume Lotus japonicus
Akihiro Suzuki1, Hisatoshi Hara, Tomoyo Kinoue
1Department of Environmental Sciences, Faculty of Agriculture, Saga University, 1 Honjyo-machi, Saga, 840-8502, Japan. azuki@cc.saga-u.ac.jp
Abstract:
We used a split-root system to determine the timing for induction of the autoregulation of nodulation (AUT) in Lotus japonicus (Regel) Larsen after inoculation with Mesorhizobium loti. The signal took at least five days for full induction of AUT and inhibition of infection thread formation. Strain ML108 (able to nodulate but unable to fix nitrogen) induced full AUT, but ML101 (unable to nodulate or to fix nitrogen) did not induce autoregulation. These results indicate that Nod factor-producing strains induce AUT, but that the nitrogen fixed by rhizobia and supplied to the plant as ammonia does not elicit the AUT in L. japonicus.
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