关键词: 苹果, 连作障碍, 棉隆熏蒸, 葱, 短期轮作, 抗氧化酶, 光合速率

Abstract: In order to provide basis for preventing and controlling apple replant disease（ARD），the Malus hupehensis Rehd.，which was planted in an Allium fistulosum rotation after dazomet fumigation under pot condition，was tested to study the growth of seedlings in continuous 2 years. The results showed that，dazomet fumigation and Allium fistulosum rotation after dazomet fumigation can significantly promote the growth of the Malus hupehensis Rehd.，but the Allium fistulosum rotation after dazomet fumigation is the best. In July 2016，compared with dazomet fumigation，the plant height，stem diameter，fresh weight，dry weight and root respiration rate of M. hupehensis Rehd. seedlings with a Allium fistulosum rotation after dazomet fumigation were increased by 34.5%，19.5%，30.0%，22.6% and 21.3%. Those indices were improved 29.9%，28.4%，35.0%，34.4% and 26.5% in July 2017. Under Allium fistulosum rotation after dazomet fumigation treatment，the root activity and the antioxidant enzymes including superoxide dismutase（SOD），peroxidase（POD），catalase（CAT）increased. The contents of MDA in root and leaf decreased，respectively. Treatment with Allium fistulosum rotation after dazomet fumigation also increased Pn，Tr，Gs and Gi of Malus hupehensis Rehd. seedling leaves. The treatment with a short time Allium fistulosum rotation after dazomet fumigation promoted the growth of M. hupeheusis Rehd.，and had the better function in prevention and control of ARD than that of dazomet fumigation，therefore，it could be an effective measure to reduce ARD.

Key words: apple, replant disease；dazomet fumigation, Allium fistulosum, short-time rotation, antioxidant enzyme, photosynthetic rate