The effects of lanthanum on some redox system(PMRS) properties of the plasma membrane(PM) vesicles from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5)stress were studied. The results show tha...The effects of lanthanum on some redox system(PMRS) properties of the plasma membrane(PM) vesicles from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5)stress were studied. The results show that there are NADH oxidase and EDTA Fe 3+ reductase, and nitrate reductase in the seedling PM, and they have different responses to soaking seeds for 8 h in a series of LaCl 3 solution. The NADH oxidase activities and the Nitrate reductase activities can be stimulated when La 3+ concentrations is in the range of 50～200 mg·L -1 , but their activities are inhibited or fluctuate by the higher La 3+ concentrations. The EDTA Fe 3+ reductase activities can be stimulated by La 3+ concentrations in the range of 50～400 mg·L -1 . The research also revealed that La 3+ reduces the relative permeability of membranes and have the function in protecting membranes under acid rain stress by the way of inhibiting the leakage of electrolyte.展开更多
The effect of NO on lanthanum-induced antioxidant activities in rice was evaluated. The results showed that the uptake and translocation of La from root to shoot were obviously inhibited by 10μmol·L^-1 sodium ni...The effect of NO on lanthanum-induced antioxidant activities in rice was evaluated. The results showed that the uptake and translocation of La from root to shoot were obviously inhibited by 10μmol·L^-1 sodium nitropmsside （SNP）, a donor of NO, in the seedlings grown in Mura B nutrient solution with 100μmol·L^-1 La. Although the content of ascorbate acid （AsA） were scarcely affected by La or NO in our experiment, La decreased significantly the activity of SOD and content of GSH, while promoted H202 content in leaves. Furthermore, NO blocked these La effects. Taken together, the results suggested that NO relieved La toxicity in rice. A possible role for NO effects on antioxidant activity was discussed.展开更多
After treated with low concentration of La^3 ＋ , the rate of producing active oxygen free radical, the relative permeability of cell membrane, the contents of bivalent iron ion in wheat seedling leaves under water st...After treated with low concentration of La^3 ＋ , the rate of producing active oxygen free radical, the relative permeability of cell membrane, the contents of bivalent iron ion in wheat seedling leaves under water stress were determined. The results show that in wheat seedling leaves, feasible concentrations of La^3 ＋ decreases the accumulation of active oxygen free radical, inhibits the increase of the relative permeability of cell membrane, reduces the content of peroxidation product MDA of membrane lipid, and prevents the plant cell producing more bivalent iron ion which can catalyzed the reaction of Haber-weiss and Fenton to produce more superoxide anion. In addition, purified plasma membrane was isolated by aqueous two-phase partitioning from wheat seedling leaves. The reduction rate of Fe（CN）6^3- by purified plasma membrane in La^3＋ -treated wheat seedling leaves is different from those in the absence of La^3＋ under water stress. The changing trend of the redox activity to La^3＋ is similar to that of the content of Fe^2＋ . The results reveal that extraneous La^3＋ can alleviate the damages of cell membrane caused by water stress via promoting the activity of redox system and the ability of eliminating ROS in wheat seedling leaves.展开更多
The effects of La(NO 3) 3 on the growth,activities of SOD,CAT and MDA content in shoots and roots of wheat seedlings under mercury stress were evaluated by the nutrient solution culture experiment. The results sugge...The effects of La(NO 3) 3 on the growth,activities of SOD,CAT and MDA content in shoots and roots of wheat seedlings under mercury stress were evaluated by the nutrient solution culture experiment. The results suggest that there is positive effect of La(NO 3) 3 on enhancing the activities of SOD,CAT,decrease of MDA content in shoots and roots of wheat seedlings during 0～5 d. But La(NO 3) 3 evens and cooperates with mercury when plants are too long under mercury stress. Mercury inhibits the growth of wheat seedlings more grievously.展开更多
The effects of La^(3+) on the growth and the ATPases activities of plasma membrane(PM) vesicles isolated from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5) stress were studied. The results show ...The effects of La^(3+) on the growth and the ATPases activities of plasma membrane(PM) vesicles isolated from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5) stress were studied. The results show that the height, length of roots, fresh weight and PM H^+-ATPase activites of Casuarina equisetifolia seedlings increase by the treatments of soaking seeds in LaCl_3 solutions with lower concentrations, and those can reach their peak values by treating with 200 mg·L^(-1) La^(3+). However, in comparison with the CK, those are inhibited by the higher La^(3+) concentrations; PM Ca^(2+)-ATPase activity is inhibited with the treatments of La^(3+). The results also reveal that the H^+-ATPase activity and the growth of cell enlarge have a remarkable positive correlation, and La^(3+) activating H^+-ATPase can facilitate plant growth. La^(3+) also can alleviate cytosolic acidification of plant under acid rain stress and indirectly maintain the stability of intracellular environment. In order to resistant to acid rain and accelerate the growth of Casuarina equisetifolia, the suitable range of La^(3+) concentrations to soak seeds for 8 h is 50～200 mg·L^(-1).展开更多
The paper briefly dealt with relieving toxic effects of La on high aquatic plant-Hydrocharis dubia B L. Backer growing in the solution containing different concentration of Ni. The results show that La can relieve the...The paper briefly dealt with relieving toxic effects of La on high aquatic plant-Hydrocharis dubia B L. Backer growing in the solution containing different concentration of Ni. The results show that La can relieve the reduction of chlorophyll content, the accumulation of MDA(malondiadehyde) and the elevation of relative membrane penetrability (RMP). After adding 10 mg . L-1 La to the solution, the activities of SOD and CAT in the leaves of Hydrocharis dubia B L. Backer increases compared with those of the single treatment of Ni, while the activity of POD decreases. It reveals that la enhances the abilities of scavenging the activated oxygen in the plant and alleviates the damage to the membranes. The soluble protein content with Ni and La compound treatment is higher than that of single Ni does, and proline content is contrary to the soluble protein content. So La improves the resistance of Hydrocharis dubia B. L. Backer to the stress of Ni. However, La can aggravate the damage to the cells under the extremely high concentration of Ni treatment.展开更多
文摘The effects of lanthanum on some redox system(PMRS) properties of the plasma membrane(PM) vesicles from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5)stress were studied. The results show that there are NADH oxidase and EDTA Fe 3+ reductase, and nitrate reductase in the seedling PM, and they have different responses to soaking seeds for 8 h in a series of LaCl 3 solution. The NADH oxidase activities and the Nitrate reductase activities can be stimulated when La 3+ concentrations is in the range of 50～200 mg·L -1 , but their activities are inhibited or fluctuate by the higher La 3+ concentrations. The EDTA Fe 3+ reductase activities can be stimulated by La 3+ concentrations in the range of 50～400 mg·L -1 . The research also revealed that La 3+ reduces the relative permeability of membranes and have the function in protecting membranes under acid rain stress by the way of inhibiting the leakage of electrolyte.
基金Project supported by the National Natural Science Foundation of China (NSFC) (30271065, 39970438)Program for New Century Excellent Talents in Xiamen University (NCETXMU, X07115)
文摘The effect of NO on lanthanum-induced antioxidant activities in rice was evaluated. The results showed that the uptake and translocation of La from root to shoot were obviously inhibited by 10μmol·L^-1 sodium nitropmsside （SNP）, a donor of NO, in the seedlings grown in Mura B nutrient solution with 100μmol·L^-1 La. Although the content of ascorbate acid （AsA） were scarcely affected by La or NO in our experiment, La decreased significantly the activity of SOD and content of GSH, while promoted H202 content in leaves. Furthermore, NO blocked these La effects. Taken together, the results suggested that NO relieved La toxicity in rice. A possible role for NO effects on antioxidant activity was discussed.
基金Project supported bythe National Natural Science Foundation of China (30270744) and 863 Program(2002AA241121)
文摘After treated with low concentration of La^3 ＋ , the rate of producing active oxygen free radical, the relative permeability of cell membrane, the contents of bivalent iron ion in wheat seedling leaves under water stress were determined. The results show that in wheat seedling leaves, feasible concentrations of La^3 ＋ decreases the accumulation of active oxygen free radical, inhibits the increase of the relative permeability of cell membrane, reduces the content of peroxidation product MDA of membrane lipid, and prevents the plant cell producing more bivalent iron ion which can catalyzed the reaction of Haber-weiss and Fenton to produce more superoxide anion. In addition, purified plasma membrane was isolated by aqueous two-phase partitioning from wheat seedling leaves. The reduction rate of Fe（CN）6^3- by purified plasma membrane in La^3＋ -treated wheat seedling leaves is different from those in the absence of La^3＋ under water stress. The changing trend of the redox activity to La^3＋ is similar to that of the content of Fe^2＋ . The results reveal that extraneous La^3＋ can alleviate the damages of cell membrane caused by water stress via promoting the activity of redox system and the ability of eliminating ROS in wheat seedling leaves.
文摘The effects of La(NO 3) 3 on the growth,activities of SOD,CAT and MDA content in shoots and roots of wheat seedlings under mercury stress were evaluated by the nutrient solution culture experiment. The results suggest that there is positive effect of La(NO 3) 3 on enhancing the activities of SOD,CAT,decrease of MDA content in shoots and roots of wheat seedlings during 0～5 d. But La(NO 3) 3 evens and cooperates with mercury when plants are too long under mercury stress. Mercury inhibits the growth of wheat seedlings more grievously.
文摘The effects of La^(3+) on the growth and the ATPases activities of plasma membrane(PM) vesicles isolated from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5) stress were studied. The results show that the height, length of roots, fresh weight and PM H^+-ATPase activites of Casuarina equisetifolia seedlings increase by the treatments of soaking seeds in LaCl_3 solutions with lower concentrations, and those can reach their peak values by treating with 200 mg·L^(-1) La^(3+). However, in comparison with the CK, those are inhibited by the higher La^(3+) concentrations; PM Ca^(2+)-ATPase activity is inhibited with the treatments of La^(3+). The results also reveal that the H^+-ATPase activity and the growth of cell enlarge have a remarkable positive correlation, and La^(3+) activating H^+-ATPase can facilitate plant growth. La^(3+) also can alleviate cytosolic acidification of plant under acid rain stress and indirectly maintain the stability of intracellular environment. In order to resistant to acid rain and accelerate the growth of Casuarina equisetifolia, the suitable range of La^(3+) concentrations to soak seeds for 8 h is 50～200 mg·L^(-1).
文摘The paper briefly dealt with relieving toxic effects of La on high aquatic plant-Hydrocharis dubia B L. Backer growing in the solution containing different concentration of Ni. The results show that La can relieve the reduction of chlorophyll content, the accumulation of MDA(malondiadehyde) and the elevation of relative membrane penetrability (RMP). After adding 10 mg . L-1 La to the solution, the activities of SOD and CAT in the leaves of Hydrocharis dubia B L. Backer increases compared with those of the single treatment of Ni, while the activity of POD decreases. It reveals that la enhances the abilities of scavenging the activated oxygen in the plant and alleviates the damage to the membranes. The soluble protein content with Ni and La compound treatment is higher than that of single Ni does, and proline content is contrary to the soluble protein content. So La improves the resistance of Hydrocharis dubia B. L. Backer to the stress of Ni. However, La can aggravate the damage to the cells under the extremely high concentration of Ni treatment.
