Non-targeted biochemical profiling (metabolomics) provided insight into the biochemical mechanisms underlying plant drought tolerance. The study was carried out by Dr. Melvin J. Oliver and colleagues, USDA-ARS scientists at the University of Missouri in Columbia, Dr. Bernard W.M. Wone and John C. Cushman and colleagues at the University of Nevada in Reno, and Dr. John Ryals, Dr. Lining Guo, and Dr. Danny Alexander at Metabolon, Inc.
To develop novel strategies for improving drought tolerance in crops, understanding how plants tolerate dehydration is a prerequisite. Non-targeted metabolomics analysis of two sister grass species, the desiccation-tolerant (DT) Sporobolus stapfianus and the desiccation-sensitive (DS) Sporobolus pyramidalis, revealed adaptive metabolic responses to dehydration. Drought tolerance was associated with higher concentrations of osmolytes, lower concentrations of metabolites associated with energy metabolism, and higher concentrations of nitrogen metabolites in the fully watered state, suggesting that the drought tolerant species is primed metabolically for dehydration stress. Under water stress a metabolic shift toward the production of protective compounds was observed in the drought tolerant plants. Biochemical alterations associated with drought tolerance included antioxidant production, nitrogen remobilization, ammonia detoxification, and soluble sugar production. Collectively, the metabolic profiles obtained uncovered a cascade of biochemical regulation strategies critical to the survival of S. stapfianus under desiccation.
The article has been published on-line in The Plant Cell Advance Online Publication.