A Simple and Rapid Assay for Measuring Phytoalexin Pisatin, an Indicator of Plant Defense Response in Pea (Pisum sativum L.).

Phytoalexins are antimicrobial substance synthesized in plants upon pathogen infection. Pisatin (Pisum sativum phytoalexin) is the major phytoalexin in pea, while it is also a valuable indicator of plant defense response. Pisatin can be quantitated in various methods from classical organic chemistry to Mass-spectrometry analysis. Here we describe a procedure with high reproducibility and simplicity that can easily handle large numbers of treatments. The method only requires a spectrophotometer as laboratory equipment, does not require any special analytical instruments (e.g., HPLC, mass spectrometers, etc.) to measure the phytoalexin molecule quantitatively, i.e., most scientific laboratories can perform the experiment.