Abstract: 【Objective】 Disease caused by after-reap soil is a challenge for planting young apple (Malus domestica) trees with this kind of soil, the effect of after-reap soil on growth and leaf antioxidant activity of different young apple trees were studied for providing evidence for alleviate after-reap disease of apple trees. 【Method】Five apple cultivars (‘Yanfu3’, ‘RedGeneral’, ‘Fuji2001’, ‘Miyakiji’, ‘Shoufu1’) were grafted on rootstocks (M. hupehensis) and planted in pots filled with after-reap soil. The same quantities of five apple cultivars were planted in sterilized soil as control. The dynamic changes of plant growth, chlorophyll content, leaf antioxidant activity, the net photosynthetic rate (Pn) and fluorescent parameters were determined.【Result】After-reap soil had different degrees of inhibition on the growth, chlorophyll content, net photosynthetic rate, fluorescence parameters and leaf antioxidant activity of different cultivars. Compared with sterilized soil (control), there were no significant difference in the growth of ‘Fuji2001’ and ‘Miyakiji’, while other cultivars showed significant differences. From July to September, leaf SOD activity of all apple cultivars in after-reap soil were lower than that of the controls. For example, ‘Fuji2001’ was reduced by 40.24%, 20.96%, and 18.16% compared with the control, and the gap with control becomes small; ‘Yanfu3’, ‘Red General’, ‘Miyakiji’, ‘Shoufu1’ were significantly lower than controls. Leaf POD activity was increased first and then decreased thereafter. In August and September, ‘Fuji2001’ and ‘Miyakiji’ were reduced by 3.02% and 5.76% in average, and there were no significant differences with their controls, however, ‘Yanfu3’, ‘Red General’ and ‘Shoufu1’ were significantly lower than controls from July to September. The leaf CAT activity in ‘Miyakiji’ was higher than other cultivars, it was 27.21% higher than the control in August; in contrast, the leaf CAT activity of other cultivars were all significantly lower than that of controls. From July to September, the net photosynthetic rate of ‘Yanfu3’ and ‘Red General’ was significantly lower than their controls, ‘Shoufu1’ was significantly lower than the control throuthout the experimental period, and others showed no significant differences. ‘Fuji2001’ and ‘Miyakiji’ had no significant differences in fluorescent parameters when compared with controls; ‘Yanfu3’, ‘Red General’ and ‘Shoufu1’ were significantly higher in NPQ than their controls. 【Conclusion】 The effects of after-reap soil on the physiological indexes and leaf antioxidant activity of young apple trees with the same rootstock were different. ‘Fuji 2001’ and ‘Miyakiji’ could resist the effects from the after-reap soil in a certain extent, however, ‘Yanfu3’, ‘Red General’ and ‘Shoufu1’ could not protect themselves well. ‘Fuji2001’ and ‘Miyakiji’ maight be the preferrable varieties for old orchards and further investigations should be carried out.

Key words: replant soil, rootstock, apple cultivars, growth, net photosynthetic rate, fluorescent parameters, leaf antioxidant activity