Studies on the superoxide anion production and peroxidase activity in potato leaf cell suspension exposed to salicylic acid

It is now widely accepted that salicylic acid (SA) signaling is mediated by reactive oxygen species (ROS) production. We have studied the effect of SA on peroxidase activity and superoxide anion production in potato leaf cell suspension. The results show that potato cells are insensitive to low concentrations of exogenous SA (< 1 mM) and the effect is observed at 1–5 mM SA. The cells exposed to SA exhibit higher peroxidase activity and show different peroxidase pattern when analyzed on native gels compared to the control. Superoxide anion production is enhanced after two hours of treatment and 2.5 mM SA gives the highest value. The results suggest peroxidase-mediated detoxification of ROS elicited by SA.