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Title: Are we there yet? The long walk towards the development of efficient symbiotic associations between nitrogen-fixing bacteria and non-leguminous crops


Nitrogen is an essential element of life, and nitrogen availability often limits crop yields. Since the Green Revolution, massive amounts of synthetic nitrogen fertilizers have been produced from atmospheric nitrogen and natural gas, threatening the sustainability of global food production and degrading the environment. There is a need for alternative means of bringing nitrogen to crops, and taking greater advantage of biological nitrogen fixation seems a logical option. Legumes are used in most cropping systems around the world because of the nitrogen-fixing symbiosis with rhizobia. However, the world's three major cereal crops-rice, wheat, and maize-do not associate with rhizobia. In this review, we will survey how genetic approaches in rhizobia and their legume hosts allowed tremendous progress in understanding the molecular mechanisms controlling root nodule symbioses, and how this knowledge paves the way for engineering such associations in non-legume crops. We will also discuss challenges in bringing these systems into the field and how they can be surmounted by interdisciplinary collaborations between synthetic biologists, microbiologists, plant biologists, breeders, agronomists, and policymakers.

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Publication Date:
Research Org.:
Univ. of Wisconsin, Madison, WI (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER)
Contributing Org.:
University of Wisconsin
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1634771
Grant/Contract Number:  
SC0018247; SC0014377
Resource Type:
Published Article
Journal Name:
BMC Biology
Additional Journal Information:
Journal Name: BMC Biology Journal Volume: 17 Journal Issue: 1; Journal ID: ISSN 1741-7007
BioMed Central
Country of Publication:
United Kingdom
60 APPLIED LIFE SCIENCES; 09 BIOMASS FUELS; nitrogen fixation; symbiosis; bioenergy crop

Citation Formats

Pankievicz, Vânia C. S., Irving, Thomas B., Maia, Lucas G. S., and Ané, Jean-Michel. Are we there yet? The long walk towards the development of efficient symbiotic associations between nitrogen-fixing bacteria and non-leguminous crops. United Kingdom: N. p., 2019. Web. doi:10.1186/s12915-019-0710-0.
Pankievicz, Vânia C. S., Irving, Thomas B., Maia, Lucas G. S., & Ané, Jean-Michel. Are we there yet? The long walk towards the development of efficient symbiotic associations between nitrogen-fixing bacteria and non-leguminous crops. United Kingdom.
Pankievicz, Vânia C. S., Irving, Thomas B., Maia, Lucas G. S., and Ané, Jean-Michel. Tue . "Are we there yet? The long walk towards the development of efficient symbiotic associations between nitrogen-fixing bacteria and non-leguminous crops". United Kingdom.
title = {Are we there yet? The long walk towards the development of efficient symbiotic associations between nitrogen-fixing bacteria and non-leguminous crops},
author = {Pankievicz, Vânia C. S. and Irving, Thomas B. and Maia, Lucas G. S. and Ané, Jean-Michel},
abstractNote = {Nitrogen is an essential element of life, and nitrogen availability often limits crop yields. Since the Green Revolution, massive amounts of synthetic nitrogen fertilizers have been produced from atmospheric nitrogen and natural gas, threatening the sustainability of global food production and degrading the environment. There is a need for alternative means of bringing nitrogen to crops, and taking greater advantage of biological nitrogen fixation seems a logical option. Legumes are used in most cropping systems around the world because of the nitrogen-fixing symbiosis with rhizobia. However, the world's three major cereal crops-rice, wheat, and maize-do not associate with rhizobia. In this review, we will survey how genetic approaches in rhizobia and their legume hosts allowed tremendous progress in understanding the molecular mechanisms controlling root nodule symbioses, and how this knowledge paves the way for engineering such associations in non-legume crops. We will also discuss challenges in bringing these systems into the field and how they can be surmounted by interdisciplinary collaborations between synthetic biologists, microbiologists, plant biologists, breeders, agronomists, and policymakers.},
doi = {10.1186/s12915-019-0710-0},
journal = {BMC Biology},
number = 1,
volume = 17,
place = {United Kingdom},
year = {2019},
month = {12}

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Cited by: 4 works
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Figures / Tables:

Fig. 1 Fig. 1: Different types of nitrogen-fixing associations with plants. The three challenges of biological nitrogen fixation are solved with different efficiency by these types of interactions—energy source, oxygen protection, and transfer of fixed nitrogen to the plant. The efficiency of each bacterial partner is indicated by + (low), ++ (moderate),more » or +++ (high). The nitrogen fixation rates depend on the efficiency of the interaction. a Root nodule symbiosis, 50–465 kg N ha−1 y−1; b associative nitrogen fixation, 2–170 kg N ha−1 y−1; and c, d free-living nitrogen fixation, 1–80 kg N ha−1 y−1« less

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Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.