Effects Of Exogenous Salicylic Acid On The Growth Of Grape And The Activity Of Antioxidant Enzymes In Leaves

In this study,the grape cv.Cabernet Sauvignon was used as materials,and the effect of exogenous salicylic acid(SA)on the photosynthetic rate,chlorophyll content,accumulation of polyphenols and antioxidant enzyme activities in the leaves were studied.The main results were as follows:1.The results showed that the leaf area and the length of internode were increased by 0.88%,11.17%,13.13%,17.52%by 0.05 mmol/L and 0.1 mmol/L SA,respectively.Whereas,the growth of leaf and internod was decreased by 0.25 mmol/L and 0.5 mmol/L SA.2.The leaf net photosynthetic rate(Pn),intercellular CO2 concentration(Ci),transpiration rate(Tr)were increased,but the stomatal conductance(Gs)decreased by SA treatment.The chlorophyll content of 0.1 mmol/1 SA treatment in 3th days was increased by 24.16%.3.The SOD activity was increased firstly and then decreased after exogenous SA treatment,whereas the CAT activity was increased,and was dose-depended.0.1 mmol/L SA resulted the increases of CAT activity,and the 0.5 mmol/L SA resulted the decreased.The MDA content was decreased,which indicated that exogenous SA could inhibated the accumulation of MDA,and then reduced the harmful of active oxygen species.4.Exogenous SA could induce the accumulation of phenolics in leaves.The result showed that the total phenolics content was increased by 28.36%at 4 days after 0.05 mmol/L SA treatment,which indicated that exogenous SA could induced the phenolics accumulation in leaf.