Updated February 25, 2025:
1) Conclusions (include observations, solutions, and/or is additional research warranted – limit of 200 words per bullet point)
• What new knowledge was developed/discovered in the research supported by the ISRC?
Soybean diseases can be affected by CO2 levels that are expected in the future - some may be unaffected or decrease in severity, whereas there is potential for others to increase in severity.
The defense responses of soybeans are affected by CO2 levels.
• What are practical applications of the research? How long?
The results of this research do not have immediate practical applications, but point to new research avenues for the future.
A lot of attention is focused on temperature and water availability, and rightfully so. However, this research demonstrates that elevated CO2 levels on their own may have impacts on plant diseases.
The outcomes warrant additional research 1) to further understand the mechanisms that underlie the altered susceptibility to pathogens in elevated CO2 conditions and 2) to determine if there are genetic factors that can be used to improve soybean resistance to pathogens in elevated CO2 environments.
Additional work is needed to understand how elevated CO2, temperature, and water availability interact to affect soybean performance.
• How might this new knowledge/discovery affect the success of positive impact for industry and/or farmers?
The knowledge provides insight into how soybeans are expected to perform in elevated CO2 environments.
The research results suggest that soybean defenses are likely to be altered in the future as CO2 levels continue to rise, which can affect disease development. This information demonstrates that efforts to genetically adapt soybeans to higher concentrations of CO2 in the atmosphere should include enhancing disease resistance under those conditions as well.
2) Supporting attachments: Publication of findings doi: 10.1111/nph.20364.
3) Other information you want to share (limit of 100 words)
Leveraged funding from the Plant Sciences Institute to complete the research project.
Data from this project was used in support of a successful USDA NIFA grant application titled: Machine Learning-Assisted Multimodal Chemical, Biological, Physiological Sensing For Assessing Multiplex Plant Stress States ($591,499)
On a different note, there were some difficulties in utilizing Enviratron rover to automate the image acquisition process, e.g., unreliable communications between the rover and chamber server, and maintenance and manipulation issues. To that end, an upgraded rover design has been developed to integrate an omnidirectional vehicle, a dual-arm configuration, and more capable imaging, ranging, and spectral sensors.
4) List conferences, publications, etc. in which this research was shared
Presented our research as a poster at the American Phytopathological Society meeting in August 2022, Pittsburgh, PA
Presented our research outcomes as a talk and poster at the International Society for Molecular Plant Microbe Interactions meeting in July 2023, Providence, RI
Presented our research at the ISU Research Day hosted by ISRC in 2024
Published the research results in a high-profile plant journal: Bredow, M., Khwanbua, E., Chicowski, A. S., Breitzman, M. W., Qi, Y., Holan, K. L., Liu, P., Graham, M. A., Whitham, S. A. (2025) Elevated CO2 alters soybean physiology and defense responses, and has disparate effects on susceptibility to diverse microbial pathogens. New Phytologist In press. doi: 10.1111/nph.20364.
5) Conclusions (include observations, solutions, and/or is additional research warranted – limit of 200 words per bullet point)
• What new knowledge was developed/discovered in the research supported by the ISRC?
o This research revealed the effect of heat stress and changes in the soil microbiome to the gene expression of soybean. We found that different genotypes have unique transcriptional responses to heat stress, but there are some conserved genes. We also found that the soil microbiome changes the expression to heat stress, and appears to alleviate some of the symptoms.
o Soil autoclaving impacts soil chemical properties, increasing phosphorus, sulfur, and manganese levels while decreasing zinc and iron.
o Autoclaved soil lacks detectable microbial DNA, confirmed through qPCR and soil respiration assays.
o Significant nodulation was observed at optimal temperatures in non-autoclaved soil treatments.
o Elevated temperatures significantly influenced microbial activity, root anatomy, and nodulation efficiency.
o High temperatures and autoclaving did influence the bacterial and fungal diversity and assembly.
o Experiments revealed the critical role of microbes in soybean growth and stress resilience.
• What are practical applications of the research? How long?
o The practical applications for this work would take many years still. These applications could be the identification of candidate genes for heat stress tolerance, which could then be bred into commercial cultivars with acceptable yield levels.
o Informing sustainable soil management practices to optimize microbial diversity to promote soil health in extreme temperatures.
o Data from this research can guide researchers, with immediate use in experimental designs for follow-up studies.
• How might this new knowledge/discovery affect the success of positive impact for industry and/or farmers?
o The knowledge gives us greater insight in how soybean adapts to heat stress, and how it can continue to thrive. This opens opportunities for further research into specific molecular pathways and genes to be used to develop heat tolerant soybean. This is further coupled with the evidence that the soil microbiome contributes to the heat stress response, and can aid in alleviating the stress.
o Promotes better soil management practices, leveraging microbes for improved crop health and productivity.
o Provides a framework for integrating microbial health into agricultural practices, benefiting farmers facing heat stress challenges.
o Fostering collaboration with industry partners to understand microbial-soil-plant interactions, for driving innovations in crop production and sustainability.
6) Supporting attachments: see attached pdf to view supporting images
7) List conferences, publications, etc. in which this research was shared
a. ASA-CSSA-SSSA Annual Meeting (October 30, 2023)
b. R.F. Baker Plant Breeding Symposium (March 22, 2024)
c. Presented our research outcomes in ASA-CSSA-SSSA meeting in 2023
d. Showcased our research in the ISU Research Day hosted by ISRC 2024
e. Presented our research at the International Phytobiomes Conference 2024
f. Published a bioRxiv pre-print (https://doi.org/10.1101/2024.11.04.620947)
g. Peer-reviewed papers (2) are under development
View uploaded report 
o The knowledge gives us greater insight in how soybean adapts to heat stress, and how it can continue to thrive. This opens opportunities for further research into specific molecular pathways and genes to be used to develop heat tolerant soybean. This is further coupled with the evidence that the soil microbiome contributes to the heat stress response, and can aid in alleviating the stress.
o Promotes better soil management practices, leveraging microbes for improved crop health and productivity.
o Provides a framework for integrating microbial health into agricultural practices, benefiting farmers facing heat stress challenges.
o Fostering collaboration with industry partners to understand microbial-soil-plant interactions, for driving innovations in crop production and sustainability.