|Leisner, Courtney - University Of Illinois|
|Yendrek, Craig - University Of Illinois|
|Ainsworth, Elizabeth - Lisa|
Submitted to: Biomed Central (BMC) Plant Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/30/2017
Publication Date: 12/10/2017
Citation: Leisner, C.P., Yendrek, C.R., Ainsworth, E.A. 2017. Physiological and transcriptomic responses in the seed coat of field-grown soybean (Glycine max L. Merr.) to abiotic stress. Biomed Central (BMC) Plant Biology. 17:242.
Interpretive Summary: Genomic approaches have proven powerful tools to understand the complex relationship among genes, proteins and metabolites involved in plant responses to abiotic stress and future climate change. In this study, the genomic response of the soybean seed coat, a tissue that regulates carbon and nitrogen flow to developing seeds, was examined in soybean grown in the field under ozone, high temperature or drought stress. All three of those environmental stresses reduced soybean photosynthesis and productivity, but only high temperature stress led to significant changes in expression of key genes. In particular, genes involved in DNA replication and cellular metabolism were altered under high temperature stress, suggesting that a key effect of growth at elevated temperatures is acceleration of developmental progression. This work identifies a potentially new target for improving soybean tolerance to rising temperature stress.
Technical Abstract: Understanding how intensification of abiotic stress due to global climate change affects crop yields is important for continued agricultural productivity. Coupling genomic technologies with physiological crop responses in a dynamic field environment is an effective approach to dissect the mechanisms underpinning crop responses to abiotic stress. Soybean (Glycine max L. Merr. cv. Pioneer 93B15) was grown in natural production environments with projected changes to environmental conditions predicted for the end of the century, including decreased precipitation, increased tropospheric ozone concentrations ([O3]), or increased temperature. All three environmental stresses significantly decreased leaf-level photosynthesis and stomatal conductance, leading to significant losses in seed yield. This was driven by a significant decrease in the number of pods per node for all abiotic stress treatments. To understand the underlying transcriptomic response involved in yield response to environmental stress, RNA-Sequencing analysis was performed on the soybean seed coat, a tissue that plays an essential role in regulating carbon and nitrogen transport to developing seeds. Gene expression analysis revealed 49, 148 and 1,576 differentially expressed genes in the soybean seed coat in response to drought, elevated [O3] and elevated temperature, respectively. Expression of genes involved in DNA replication and metabolic processes were enriched in the seed coat under high temperate stress, suggesting that the timing of events that are important for cell division and proper seed development are altered in a stressful growth environment.