The establishment of the nitrogen‐fixing symbiosis between soybean and
In this study, the three-dimensional spatial distributions of a number of metabolites involved in regulating symbiosis and biological nitrogen fixation (BNF) within soybean root nodules were revealed using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). While many metabolites exhibited distinct spatial compartmentalization, some metabolites were asymmetrically distributed throughout the nodule (e.g., S-adenosylmethionine). These results establish a more complex metabolic view of plant–bacteria symbiosis (and BNF) within soybean nodules than previously hypothesized. Collectively these findings suggest that spatial perspectives in metabolic regulation should be considered to unravel the overall complexity of interacting organisms, like those relating to associations of nitrogen-fixing bacteria with host plants.
more » « less- Award ID(s):
- 1734145
- NSF-PAR ID:
- 10154417
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- The ISME Journal
- Volume:
- 12
- Issue:
- 9
- ISSN:
- 1751-7362
- Format(s):
- Medium: X Size: p. 2335-2338
- Size(s):
- ["p. 2335-2338"]
- Sponsoring Org:
- National Science Foundation
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Abstract The symbiotic relationship between soybean [
Glycine max L. (Merr.)] roots and bacteria (Bradyrhizobium japonicum ) lead to the development of nodules, important legume root structures where atmospheric nitrogen (N2) is fixed into bio‐available ammonia (NH3) for plant growth and development. With the recent development of the Soybean Nodule Acquisition Pipeline (SNAP), nodules can more easily be quantified and evaluated for genetic diversity and growth patterns across unique soybean root system architectures. We explored six diverse soybean genotypes across three field year combinations in three early vegetative stages of development and report the unique relationships between soybean nodules in the taproot and non‐taproot growth zones of diverse root system architectures of these genotypes. We found unique growth patterns in the nodules of taproots showing genotypic differences in how nodules grew in count, size, and total nodule area per genotype compared to non‐taproot nodules. We propose that nodulation should be defined as a function of both nodule count and individual nodule area resulting in a total nodule area per root or growth regions of the root. We also report on the relationships between the nodules and total nitrogen in the seed at maturity, finding a strong correlation between the taproot nodules and final seed nitrogen at maturity. The applications of these findings could lead to an enhanced understanding of the plant‐Bradyrhizobium relationship and exploring these relationships could lead to leveraging greater nitrogen use efficiency and nodulation carbon to nitrogen production efficiency across the soybean germplasm.
