Effect of benzoic acid and aspirin on chilling tolerance and photosynthesis in young maize plants

It was recently reported that salicylic acid (SA) treatment may provide pro tection against low temperature stress in young maize plants (JANDA et al., 1999). In the present study it is shown that certain related compounds (be nzoic acid, acetyl SA) map also reduce the symptoms of chilling injury in y oung maize plants. At normal growth temperature, however these compounds ma y cause severe damage to the plants. There is a decrease in net photosynthe sis, stomatal conductivity and transpiration after 1 day of benzoic acid or aspirin treatment at 22/20 degrees C. These compounds may cause a decrease in the growth rate in young, developing maize seedlings. It is suggested t hat an alteration in the activity of antioxidant enzymes may play a role in the increased chilling tolerance induced by these compounds.