In this thesis, 10 species of kiwifruit rootstocks were treated with hydroponics hypoxia to study their root zone hypoxia tolerance. The results were as follows: growth of all kiwifruit seedlings was inhibited. The ma...In this thesis, 10 species of kiwifruit rootstocks were treated with hydroponics hypoxia to study their root zone hypoxia tolerance. The results were as follows: growth of all kiwifruit seedlings was inhibited. The max length of new root, plant height, plant biomass, root activity, relative growth rate of leaves, and content of chlorophyll in leaves under root zone hypoxia stress obviously declined comparing with control. MDA content, relative conductance in the leaves and roots all increased in 10 kinds of kiwifruit seedlings. The sensitivities of 10 kinds’ kiwifruit seedlings to hypoxia stress were obviously different. With the method of subordinate function and cluster analysis, the adversity resistance coefficient of 10 kinds’ kiwifruit seedlings, were comprehensively evaluated in order to appraise their hypoxia-tolerance abilities. According to the results, “Hayward”, “Qinmei”, “Jinxiang”, “Kuoye”, “Huayou” kiwifruit seedlings held higher tolerance to root zone hypoxia stress, while “Hongyang” kiwifruit seedlings were sensitive to root zone hypoxia stress. The others, including “Xixuan”, “Maohua”, “Jinhua”, “Shanli” kiwifruit seedlings kept moderate resistant intensity to root zone hypoxia stress. The kiwifruit seedlings’ resistance order from strong to weak was: “Hayward” > “Qinmei” > “Jinxiang” > “Kuoye” > “Huayou” > “Xixuan” > “Maohua” > “Jinhua” > “Shanli” > “Hongyang”.展开更多
The changes of antioxidant enzyme activities and related genes expression of tomato seedlings were evaluated under hypoxia stress with different levels of Mn2+. Activities of superoxide dismutase (SOD), peroxidase (PO...The changes of antioxidant enzyme activities and related genes expression of tomato seedlings were evaluated under hypoxia stress with different levels of Mn2+. Activities of superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxide (APX), glutathione reductase (GR), catalase (CAT), the contents of H2O2, ascorbic (AsA) and malondialdehyde (MDA) were studied to investigate how active oxygen damaged the membrane lipid under hypoxia stress. With 10-200 μmol?L-1 Mn2+, the activities of SOD, POD, APX, GR and the contents of H2O2, AsA, MDA of leaves and roots increased significantly, which indicated that low Mn2+ could eliminate the active oxygen and protect the membrane lipid from hurt. But the activities of catalase (CAT) decreased evidently in the root. When the concentration of Mn2+ reached 400-600 μmol?L-1 under hypoxia stress, the activities of SOD, POD, APX, GR and ASA content decreased remarkably. However, the contents of H2O2 and MDA increased contrarily. A series of resistance genes level achieved peak value with 10 μmol?L-1 Mn2+. The expression level of SOD, CAT, APX, POD, GR were 6.28, 2.19, 5.66, 5.21 and 6.79 times compared to control respectively. These results illustrated appropriate amount of Mn2+ could reduce the damage of active oxygen under hypoxia stress, but reversely, high level of Mn2+ just aggravated the already serious damage to the tomato seedlings.展开更多
文摘In this thesis, 10 species of kiwifruit rootstocks were treated with hydroponics hypoxia to study their root zone hypoxia tolerance. The results were as follows: growth of all kiwifruit seedlings was inhibited. The max length of new root, plant height, plant biomass, root activity, relative growth rate of leaves, and content of chlorophyll in leaves under root zone hypoxia stress obviously declined comparing with control. MDA content, relative conductance in the leaves and roots all increased in 10 kinds of kiwifruit seedlings. The sensitivities of 10 kinds’ kiwifruit seedlings to hypoxia stress were obviously different. With the method of subordinate function and cluster analysis, the adversity resistance coefficient of 10 kinds’ kiwifruit seedlings, were comprehensively evaluated in order to appraise their hypoxia-tolerance abilities. According to the results, “Hayward”, “Qinmei”, “Jinxiang”, “Kuoye”, “Huayou” kiwifruit seedlings held higher tolerance to root zone hypoxia stress, while “Hongyang” kiwifruit seedlings were sensitive to root zone hypoxia stress. The others, including “Xixuan”, “Maohua”, “Jinhua”, “Shanli” kiwifruit seedlings kept moderate resistant intensity to root zone hypoxia stress. The kiwifruit seedlings’ resistance order from strong to weak was: “Hayward” > “Qinmei” > “Jinxiang” > “Kuoye” > “Huayou” > “Xixuan” > “Maohua” > “Jinhua” > “Shanli” > “Hongyang”.
文摘The changes of antioxidant enzyme activities and related genes expression of tomato seedlings were evaluated under hypoxia stress with different levels of Mn2+. Activities of superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxide (APX), glutathione reductase (GR), catalase (CAT), the contents of H2O2, ascorbic (AsA) and malondialdehyde (MDA) were studied to investigate how active oxygen damaged the membrane lipid under hypoxia stress. With 10-200 μmol?L-1 Mn2+, the activities of SOD, POD, APX, GR and the contents of H2O2, AsA, MDA of leaves and roots increased significantly, which indicated that low Mn2+ could eliminate the active oxygen and protect the membrane lipid from hurt. But the activities of catalase (CAT) decreased evidently in the root. When the concentration of Mn2+ reached 400-600 μmol?L-1 under hypoxia stress, the activities of SOD, POD, APX, GR and ASA content decreased remarkably. However, the contents of H2O2 and MDA increased contrarily. A series of resistance genes level achieved peak value with 10 μmol?L-1 Mn2+. The expression level of SOD, CAT, APX, POD, GR were 6.28, 2.19, 5.66, 5.21 and 6.79 times compared to control respectively. These results illustrated appropriate amount of Mn2+ could reduce the damage of active oxygen under hypoxia stress, but reversely, high level of Mn2+ just aggravated the already serious damage to the tomato seedlings.
