Effect of Rootstock-scion Interaction on Antioxidant Enzyme System in Leaves of Grafted Eggplant Seedlings under Low Temperature Stress

In order to study the contribution of rootstock and scion to cold resistance of grafted eggplant seedlings,two rootstock eggplant cultivars,Daidaro(D,susceptible to cold)and Hiranasu(H,with more resistantce) were used to be grafted on each other.And then the activities of SOD,POD and CAT in the leaves of the grafted seedlings were analyzed.The results showed that low temperature stress led to the reduction first and then increase of SOD and CAT activities at the initial stage;with the prolongation of stress time,their activities declined.But the POD activity increased at the initial stage and then declined along.During the low temperature stress,the activities of SOD,POD and CAT in Hiranasu leaves were higher than those in Daidaro leaves in the same combination,and the antioxidant enzyme activity of the combinations were in order of H/HDH/HDH/DHDH/DD/D.In result,the scion and roots of Hiranasu could enhance the cold resistance of Daidaro while those of Daidaro weakened the cold resistance of Hiranasu;the rootstock roots had more contribution to the cold resistance of grafted seedlings than scion.