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Syringic acid from rice as a biological nitrification and urease inhibitor and its synergism with 1,9-decanediol

Biology and Fertility of Soils volume 58, pages 277–289 (2022)Cite this article

Abstract

The type, functions, and mechanisms of biological nitrification inhibitors (BNIs) from rice were investigated using a combination of chemical and molecular techniques, bacterial bioassays, and soil microcosm experiments. We report the discovery of an effective nitrification inhibitor, syringic acid, in the root exudates of rice. Nitrification inhibition activity by syringic acid was verified in both weakly acidic and neutral pure cultures of Nitrosomonas europaea, and was superior to the widely used synthetic nitrification inhibitor, dicyandiamide (DCD). Moreover, syringic acid exhibited a dual inhibitory effect on ammonia monooxygenase (AMO), active in ammonium/ammonia oxidation, and on urease, active in urea hydrolysis. Nitrification inhibition by syringic acid was also demonstrated in a paddy soil system, and the abundance of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) was significantly inhibited under all syringic acid treatments. A synergistic effect of syringic acid and another rice BNI, 1,9-decanediol, on nitrification was found in two pure Nitrosomonas cultures and a paddy soil. Together, our results enhance our understanding of BNI production by rice and enable the design of natural inhibitor formulations that regulate soil N transformation in a concerted manner.

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Funding

This work was supported by grants from the National Natural Science Foundation of China (31761143015, 32072670), the Natural Science Foundation for Excellent Young Scholar of Jiangsu Province of China (BK20190108), the Key Research and Development Program of Shandong Province of China (2019JZZY010701), and the Open Foundation of State Key Laboratory of Soil and Sustainable Agriculture of China (Y812000007).

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Authors and Affiliations

  1. State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing, 210008, China

    Yufang Lu, Xiaonan Zhang, Mingkun Ma, Weijun Zu & Weiming Shi

  2. School of BioSciences, The University of Melbourne, Parkville, VIC, 3010, Australia

    Herbert J. Kronzucker

  3. Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada

    Herbert J. Kronzucker

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  1. Yufang Lu
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  2. Xiaonan Zhang
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Correspondence to Weiming Shi.

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Lu, Y., Zhang, X., Ma, M. et al. Syringic acid from rice as a biological nitrification and urease inhibitor and its synergism with 1,9-decanediol. Biol Fertil Soils 58, 277–289 (2022). https://doi.org/10.1007/s00374-021-01584-y

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Keywords

  • Biological nitrification inhibitor
  • Urease activity
  • Syringic acid
  • Ammonia oxidizer
  • Synergism
  • Rice