A semi-quantitative histochemical method for assessment of biochemical responses to osmotic stress in Coffea arabica leaf disks

A simple method set for assessing biochemical changes associated with osmotic stress responses was developed using coffee (Coffea arabica L.) leaf disks. Stress was induced by polyethylene glycol (PEG) exposure. Quantitative evaluation of tissue physiological stress parameters was carried out using analytical methods to validate the conversion of classic qualitative histochemical tests for localizing lipid peroxidation, hydrogen peroxide, and total xanthine alkaloids into semi-quantitative assays. Relative electrolyte leakage (EL