Dr. Joshua Blakeslee

Developing metabolomics tools to dissect plant stress responses

Photo credit: International rice Research Institute

     On November 1, 2018, Dr. Joshua Blakeslee presented his research in the Department of Plant Science and Landscape Architecture’s Plant Science seminar series. Dr. Blakeslee is an Associate Professor in the Department of Horticulture and Crop Science and Director of the Ohio Agricultural Research and Development Center (OARDC)Metabolite Analysis Cluster at The Ohio State University, Wooster. Dr. Blakeslee’ talk was entitled, “Developing metabolomics tools to dissect plant stress responses”.

      Dr. Blakeslee began his talk by highlighting various kinds of biotic and abiotic stresses experienced by plants using an example of rice plant. He described the general model to study stress response in plants which comprises stimulus, perception, transduction and metabolism, and adaptive growth. Although there are different approaches to study plant stress responses, Dr. Blakeslee argued that metabolomics is the closest approach to a phenotypic response in real time. Metabolomics is the technique used for identification and characterization of molecules, especially metabolites. He gave a brief overview of the OARDC Metabolic Analysis Cluster (OAMAC) facility which comprises state of art instrumentation for metabolic fingerprinting of microbial, plant, industrial, and food samples.

Phytohormone profiling is one of the major mandates of Dr. Blakeslee’s research group. It can be very challenging to accurately measure hormones due to their transient and unstable nature. “Quantifying phytohormones is like hunting wild animals”, joked Dr. Blakeslee.

After providing background about plant stress response and metabolomics, Dr. Blakeslee presented some results fromhis studies on salt stress response in rice and rough blue grass.Their experiments demonstrated that salt stress causes halotropism (adaptive growth of roots away from salts) in rice and rough blue grass. In rice, Phosphatidic acid and Protein Phosphatase 2A (PP2A) gene are involved in halotropism. In rough blue grass, blue light exposure enhances halotropism under salts stress by potentially inducing flavonoid production. Dr. Blakeslee hypothesized that PP2A modulates halotropism by influencing auxin transport or
metabolism.
Dr. Blakeslee briefly mentioned a project investigating the antibacterial potential of
burdock leaf extract. In some cases, the burdock extract was more effective than traditional
antibiotics. Lastly, Dr. Blakeslee provided an example of applying metabolomics in farm fields,
where he mentioned the development of field-based detectors for 2,4-D drift detection with
sensitivity of up to 300 feet distance.
“We use biochemical physiology as a tool kit to dissect and quantify biotic and abiotic stress
responses in real time”, concluded Dr Blakeslee.
Lovepreet Singh
PLSC 619