Response of protective enzymes activities in grafted chrysanthemum to heat stress

【Objective】This study investigated the effects of grafting on heat resistance of different organs of chrysanthemum.【Method】The activities of superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT)in leaves,roots and stems of grafted and cutting seedlings of chrysanthemum were studied at temperature of 40℃.【Result】The SOD,POD,and CAT activities in leaves,roots and stems of grafted chrysanthemum seedlings were significantly higher than that of cutting ones.The average SOD,POD,and CAT activities in leaves,roots and stems increased by 11.6%,378.0%and 260.1%;125.5%,131.3%and 203.1%;and 90.1%,98.0%and 90.5%,respectively.In leaves of grafted seedlings,SOD activity had the largest value of 375U/g.In roots of grafted seedlings,POD activity had the largest value of 605.87U/g.In stems of grafted seedlings,POD activity was slightly higher than the other two.【Conclusion】Grafting is an effective cultivation method to improve the resistance of chrysanthemum to heat stress.The heat resistances of different organs are significantly different.