Effects of water stress on the activities of antioxidant enzymes of Malus L.plant
水分胁迫对苹果属植物抗氧化酶活性的影响研究

The changes in activities of SOD, CAT, POD and MDA contents in leaves and roots of three different species of Malus L. were studied under the water stress. The results show that the activities of SOD, CAT and POD are gradually increased under the water stress conditions. CAT activity firstly reaches the highest point when the absolute water content of soil decreases to 6.5%, but the highest point of SOD activity is at 2.8%, then their activities are decreased with further increasing of water stress, and are partly recovered by rewatering. The highest point of POD activity appears when the absolute water content of soil declines to 3.2%, declines again with further increase of water stress and still decreases after rewatering. MDA content is gradually increased under the water stress conditions, and arrives at the highest point when the absolute water content of soil declines to 1.8% and decreases after rewatering. It is concluded that the order of antioxidization abilities of the species is M.sieverii>M micromalus>M.hupehensis.