Mitigative Effect of Salicylic Acid on Chilling Stress-Induced Injuries in Brassica oleracea L. Seedlings

Mitigative effect of exogenous salicylic acid(SA) on chilling stress-indued injuries was studied in Brassica oleracea L.Seedings. The leaves of Brassica oleacea L.seedlings were sprayed by the different concentration of SA before chilling resistance.The result showed that the pretreatment with 0.1 mmol/L,0.5 mmol/L,1.0 mmol/LSA could enhance the content of soluble suger and protein and the activities of the protected enzyme,and reduce the content of MDA under chilling resistance.As a result,the SA concentration with best effect was 0.5 mmol/L.The effect of SA on chilling resistance at the different time was studied.The result manifested that the activities of the protected enzyme,soluble suger and protein contents were firstly increased and then decreased as the time extended,but markly higher than that in control at the same time.The MDA content was also firstly increased and then decreased,but markly lower than that in control at the same time.Therefore,the injuries caused by chilling stress are mitigatived by exogenous salicylic acid(SA) in Brassica oleracea L.seedings.