Pb,Cu,Cd,Zn content of soil in mining areas and abandoned land,flats of the Pijiang River and farmlands were inves-tigated.On this basis of soil heavy metal pollution,the changes of antioxidant enzyme system in maize(...Pb,Cu,Cd,Zn content of soil in mining areas and abandoned land,flats of the Pijiang River and farmlands were inves-tigated.On this basis of soil heavy metal pollution,the changes of antioxidant enzyme system in maize(Qiandan 88)under different Pb concentrations(0,20,40,60,80,100,150,200,500,1000,2000,3000 mg/L)stress were studied.The results show that the content of Pb,Cu,Cd,and Zn in soil is the highest in mining areas and abandoned land,followed by flats of the Pijiang River>farmlands,and that the variation range of Pb,Cu,Cd in mining areas and abandoned land are 106.40-2564.72,14.83-490.88,22.57-712.77 mg/kg,respectively,which are higher than that of the other land use types.When maize is under stress of 20-500 mg/L Pb concentration,T-SOD activity of maize leaves increase with the increase of Pb concentration and the highest value is 50.21 U/mg prot,but under Pb concentration>1000 mg/L stress,T-SOD activity of maize leaves decrease gradually.The activity of POD decreases with the increases of Pb concentra-tion,and the lowest POD activity of leaves in maize with the value of 93.24 U/mg prot is appeared in Pb 1000 mg/L concentration treatment group.MDA content in leaves of maize increases with the increase of the Pb concentration and the highest value is 101.98 nmol/mg prot,then the content of MDA decreases gradually when the Pb concentration is more than 500 mg/L,which indicates that the membrane lipid peroxidation of maize leaves under high concentration of Pb stress is serious and leads to the cell damage.展开更多
The effect of Cd, Pb stress on the activated oxygen scavenging system indicates thatthe content of chlorophyll, chlorophyll a/b ratio and the activity of CAT gradually decrease,the activity of SOD increases first and ...The effect of Cd, Pb stress on the activated oxygen scavenging system indicates thatthe content of chlorophyll, chlorophyll a/b ratio and the activity of CAT gradually decrease,the activity of SOD increases first and then decreases, and the activity of POD gradually increases with increasing concentrations of Cd and Ph. Between Cd and Ph there is synergism inthe activated oxygen scavenging system. The results show that the stress of Cd and Pb can affect the scavenging system of activated oxygen and result in imbalance of activated oxygenmetabolism.展开更多
Lead (Pb) is an important environmental pollutant extremely toxic to plants and other living organisms including humans. To assess Pb phytotoxicity, a pot culture experiment was carried out using two groundnut cultiva...Lead (Pb) is an important environmental pollutant extremely toxic to plants and other living organisms including humans. To assess Pb phytotoxicity, a pot culture experiment was carried out using two groundnut cultivars (Arachis hypogaea L. cultivar K6 and cultivar K9) on plant growth, ROS levels, lipid peroxidation, and antioxidant metabolism using biochemical, histochemical methods. Plants were grown in pots for 14 days, in the botanic garden, and subjected to Pb-stress (0, 100, 200, 400 and 800 ppm) by adding Pb (NO3)2 solution and further allowed to grow for 10 days. The results showed that cultivar K6 registered lower Pb accumulation than cultivar K9, however, localization of Pb was greater in roots than leaves in both groundnut cultivars. The Pb-stress results in an increase in free radicals (O2?- and H2O2) generation in both groundnut cultivars, but more significantly in cultivar K9 than K6. Pb-stress also caused significant changes in the rate of peroxidation as shown in the levels of malondialdehyde (MDA) content in roots and leaves of both groundnut cultivars. Free proline, ascorbic acid (AsA) and non-protein thiol (NP-SH) contents were increased in cultivar K6 due to Pb-stress, but less in cultivar K9. Pb treated plants showed increased levels of antioxidant enzymes such as superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX) glutathione reductase (GR) and glutathione S-transferase (GST). Isozyme band intensities of SOD, GPX and APX were more consistent with the respective changes in antioxidative enzyme activities. These results indicate that cultivar K6 possesses greater tolerance potential for Pb toxicity than cultivar K9.展开更多
基金supported by special project of Basic Research in Yunnan Local Colleges and Universities(2017FH001-026,2018FH001-004)the National Natural Science Foundation of China(31300349)Scientific and Technological Innovation team Project of Agricultural Resources Utilization of Kunming University,Scientific Research Fund Project of Yunnan Provincial Department of Education(2021Y730,2021Y716).
文摘Pb,Cu,Cd,Zn content of soil in mining areas and abandoned land,flats of the Pijiang River and farmlands were inves-tigated.On this basis of soil heavy metal pollution,the changes of antioxidant enzyme system in maize(Qiandan 88)under different Pb concentrations(0,20,40,60,80,100,150,200,500,1000,2000,3000 mg/L)stress were studied.The results show that the content of Pb,Cu,Cd,and Zn in soil is the highest in mining areas and abandoned land,followed by flats of the Pijiang River>farmlands,and that the variation range of Pb,Cu,Cd in mining areas and abandoned land are 106.40-2564.72,14.83-490.88,22.57-712.77 mg/kg,respectively,which are higher than that of the other land use types.When maize is under stress of 20-500 mg/L Pb concentration,T-SOD activity of maize leaves increase with the increase of Pb concentration and the highest value is 50.21 U/mg prot,but under Pb concentration>1000 mg/L stress,T-SOD activity of maize leaves decrease gradually.The activity of POD decreases with the increases of Pb concentra-tion,and the lowest POD activity of leaves in maize with the value of 93.24 U/mg prot is appeared in Pb 1000 mg/L concentration treatment group.MDA content in leaves of maize increases with the increase of the Pb concentration and the highest value is 101.98 nmol/mg prot,then the content of MDA decreases gradually when the Pb concentration is more than 500 mg/L,which indicates that the membrane lipid peroxidation of maize leaves under high concentration of Pb stress is serious and leads to the cell damage.
文摘The effect of Cd, Pb stress on the activated oxygen scavenging system indicates thatthe content of chlorophyll, chlorophyll a/b ratio and the activity of CAT gradually decrease,the activity of SOD increases first and then decreases, and the activity of POD gradually increases with increasing concentrations of Cd and Ph. Between Cd and Ph there is synergism inthe activated oxygen scavenging system. The results show that the stress of Cd and Pb can affect the scavenging system of activated oxygen and result in imbalance of activated oxygenmetabolism.
文摘Lead (Pb) is an important environmental pollutant extremely toxic to plants and other living organisms including humans. To assess Pb phytotoxicity, a pot culture experiment was carried out using two groundnut cultivars (Arachis hypogaea L. cultivar K6 and cultivar K9) on plant growth, ROS levels, lipid peroxidation, and antioxidant metabolism using biochemical, histochemical methods. Plants were grown in pots for 14 days, in the botanic garden, and subjected to Pb-stress (0, 100, 200, 400 and 800 ppm) by adding Pb (NO3)2 solution and further allowed to grow for 10 days. The results showed that cultivar K6 registered lower Pb accumulation than cultivar K9, however, localization of Pb was greater in roots than leaves in both groundnut cultivars. The Pb-stress results in an increase in free radicals (O2?- and H2O2) generation in both groundnut cultivars, but more significantly in cultivar K9 than K6. Pb-stress also caused significant changes in the rate of peroxidation as shown in the levels of malondialdehyde (MDA) content in roots and leaves of both groundnut cultivars. Free proline, ascorbic acid (AsA) and non-protein thiol (NP-SH) contents were increased in cultivar K6 due to Pb-stress, but less in cultivar K9. Pb treated plants showed increased levels of antioxidant enzymes such as superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX) glutathione reductase (GR) and glutathione S-transferase (GST). Isozyme band intensities of SOD, GPX and APX were more consistent with the respective changes in antioxidative enzyme activities. These results indicate that cultivar K6 possesses greater tolerance potential for Pb toxicity than cultivar K9.
