Effect of heat shock on permeability of plasma membrane and activities of antioxidative enzymes in maize seedlings under chilling stress.

Effect of heat shock on permeability of plasma membrane and activities of antioxidative enzymes in maize seedlings under chilling stress was studied.The results showed that heat-shock pretreatments significantly increased survival percentage of maize seedlings under severe chilling stress,indicating that heat-shock could induce chilling resistance in maize seedlings.At the same time,it had been found that heat shock increased SOD,GR,CAT,APX and GPX activities and decreased cytomembrane permeability during chilling stress,indicating that heat shock enhanced chilling tolerance of maize seedlings by increasing SOD,GR,CAT,APX and GPX activities to protect cell membrane from destruction and that antioxidative enzymes could play an important role in the formation of heat-shock-induced chilling tolerance.