|YANG, LIMING - University Of Georgia|
|FOUNTAIN, JAKE - University Of Georgia|
|LEE, ROBERT - University Of Georgia|
|CHEN, SIXUE - University Of Florida|
|KEMERAITY, ROBERT - University Of Georgia|
Submitted to: American Phytopathological Society
Publication Type: Abstract Only
Publication Acceptance Date: 7/1/2016
Publication Date: 7/30/2016
Citation: Yang, L., Fountain, J., Ni, X., Lee, R.D., Chen, S., Scully, B.T., Kemeraity, R.C., Guo, B. 2016. Differential metabolome analysis of field-grown maize kernels in response to drought stress [abstract]. American Phytopathological Society.
Technical Abstract: Field drought stress decreases maize growth and yield, and aggravates pre-harvest aflatoxin contamination in kernels. In order to identify drought responsive metabolites and explore pathways involved in kernel responses, a metabolomics analysis was conducted on kernels from a drought tolerant line, Lo964, and a sensitive line, B73. Kernels were collected from each line under irrigated and drought stress treatments 7 and 14 days after drought induction beginning 7 days after pollination. Using ultra-performance liquid chromatography coupled with MS/MS, we profiled 445 metabolites covering 42 pathways. Drought stress induced higher accumulation of glycerolipids and phospholipid metabolites, and decreased content of galactolipids, amines and polyamines, amino sugars, and nucleotide sugar metabolites in both lines. However, B73 was found to accumulate fewer metabolites involved in dipeptide and pyrimidine metabolism under drought stress than Lo964. Lo964 also exhibited increases in sphingolipid, sterol, and purine metabolism in comparison to B73. Collectively, higher sugar accumulation, a lower rate of energy metabolism, and lipid and nucleic acid turnover was observed in B73. Conversely, higher amino acid and dipeptide accumulation, a lower TCA cycle rate, and elevated lipid and nucleic acid turnover was observed in Lo964 in response to drought stress. These results suggest that drought sensitivity is associated with differential metabolite accumulation, and diverse metabolic pathways in maize kernels.