Three bacterial endophytes of Sedum alfredii, VI8L2, II8L4 and VI8R2, were examined for promoting soil Zn bioavailability and Zn accumulation in S. alfredii. Results showed that three strains were re-introduced into S...Three bacterial endophytes of Sedum alfredii, VI8L2, II8L4 and VI8R2, were examined for promoting soil Zn bioavailability and Zn accumulation in S. alfredii. Results showed that three strains were re-introduced into S. alfredii rhizosphere soils under Zn stress and resulted in better plant growth, as roots biomass increased from 80% to 525% and shoot biomass from 11% to 47% compared with the uninoculated ones. Strains IVsLz, II8L4 and IVsR2 significantly increased shoot and root Zn concentrations in the ZnCO3 contaminated soil. Inoculation with strain IVsL2 resulted in 44% and 39% higher shoot and root Zn concentrations, while strain IV8R2 significantly decreased shoot Zn concentration in the Zn3(PO4)2 contaminated soils. In the aged contaminated soil, isolates IVsL2, IIsL4 and IVsR2 significantly increased root Zn concentration, but decreased shoot Zn concentration of Sedum alfredii. It suggested that endophytes might be used for enhancing phytoextraction efficiency.展开更多
The effects of five amendments such as acetic acid(AA), citric acid (CA), ethylenediamine tetraacetic acid (EDTA), sepiolite and phosphogypsum on growth and metal uptake of giant reed (Arundo donax L.) grown o...The effects of five amendments such as acetic acid(AA), citric acid (CA), ethylenediamine tetraacetic acid (EDTA), sepiolite and phosphogypsum on growth and metal uptake of giant reed (Arundo donax L.) grown on soil contaminated by arsenic (As), cadmium (Cd) and lead (Pb) were studied. The results showed that the shoot biomass of giant reed was enhanced by 24.8% and 15.0%, while superoxide mutase and catalase activities slightly varied when adding 5.0 mmol/kg CA and 2.5 mol/kg EDTA to soil as compared to the control, respectively. The concentrations of As, Cd and Pb in shoots were remarkably increased by the addition of 2.5 mmol/kg AA and CA, 5.0 mmol/kg EDTA, and 4.0 g/kg sepiolite as compared to the control. The accumulations of As and Cd were also significantly enhanced in the above condition, while the shoot Pb accumulation was noticeably enhanced by amending with 4.0 g/kg sepiolite and 8.0 g/kg phosphogysum, respectively. The results suggested that AA, CA and sepiolite could be used as optimum soil amendments for giant reed remediation system.展开更多
Phytoremediation is an efficient and economic ecological technology. It includes phytostabilization, phytovolatilization, and plant absorption. In the research, status quo and progress of Phytostabilization and plant ...Phytoremediation is an efficient and economic ecological technology. It includes phytostabilization, phytovolatilization, and plant absorption. In the research, status quo and progress of Phytostabilization and plant absorption in soils polluted with heavy metals in metal mines were summarized, including the characteristics and status quo of phytoremediation and selection method of hyperaccumulator. In addition, further research was proposed as well.展开更多
[Objective] The aim was to study the phytoremediation of heavy metal pollution in river sediment by Medicago sativa L.,so as to provide reliable references for the phytoremediation of heavy metal pollution in river se...[Objective] The aim was to study the phytoremediation of heavy metal pollution in river sediment by Medicago sativa L.,so as to provide reliable references for the phytoremediation of heavy metal pollution in river sediment.[Method] The air-dried,screened and mixed sediment was put in rectangular PVC box(0.6 m×0.5 m×0.4 m) with seepage vent at the bottom,and the water holding capacity(WHC) of sediment was kept at 30%-60% by deionized water.The seeds of Medicago sativa L.were sown in April 2010,and seedlings were thinned after 7 d.Samples were collected from rhizosphere soil every 30 d,and were used to determine the content of heavy metals,bacteria quantity and enzyme activity in sediment.In addition,the accumulation of heavy metals in the roots,stems and leaves of plant was measured after harvest in October.[Result] Different parts of Medicago sativa L.varied in accumulation capacity to different heavy metals.The accumulation amount of Zn in Medicago sativa L.was the highest,especially in roots.Meanwhile,the accumulation amount of heavy metals like Ni,Cr,Cu and Pb in roots was higher than that of stems and leaves.In contrast,Mn was mainly accumulated in leaves and its amount accounted for 42.47% of the total amount in plant.Besides,the accumulation amount of all heavy metals was the lowest in stems.Ni,Cr,Cu and Pb could be degraded more effectively than Mn,and increasing the planting time and sowing times of crop was beneficial to the degradation of heavy metals.After planted Medicago sativa L.,the quantity of microorganisms in sediment went up obviously,and dehydrogenase activity also showed an increaseing trend.[Conclusion] Medicago sativa L.has certain restoring effect on Zn,Ni,Cr,Cu and Pb,and could be used to restore heavy metal pollution in river sediment.展开更多
[Objective] The research aimed to study the response and accumulation characteristics of Cd in Polygonum pubescens Bl.[Method] Taking Hoagland nutritional solution as the culture substrate,eight kinds of Cd concentrat...[Objective] The research aimed to study the response and accumulation characteristics of Cd in Polygonum pubescens Bl.[Method] Taking Hoagland nutritional solution as the culture substrate,eight kinds of Cd concentrations (0,25,50,100,200,500,800,1 000 mg/L) were set up.[Result] Under low concentrations of Cd (25 and 50 mg/L),the biomass of P.pubescens had no significant difference with CK (P0.05).Under all the test concentrations of Cd,Cd content in the roots and shoots of P.pubescens exceeded 100 mg/kg and the enrichment coefficients of Cd were over 1.With the increasing of Cd concentration,Cd content and Cd accumulation amount in P.pubescens increased significantly.When Cd concentration exceeded 50 mg/L,translocation capacity coefficient was greater than 1.[Conclusion] Polygonum pubescens has high tolerance and accumulation capacity of Cd,and it may has some potential on the phytoremediation of Cd-contaminated soil.展开更多
[Objective] The remediation effect of the plant to Cd-contaminated soil was studied. [Method] By taking simulation test and field test, the ryegrass (Lolium perenne L.) was planted, and the remediation effect of the...[Objective] The remediation effect of the plant to Cd-contaminated soil was studied. [Method] By taking simulation test and field test, the ryegrass (Lolium perenne L.) was planted, and the remediation effect of the plant to contaminated sites was studied. [Result] The ryegrass was planted in the eluotropic soil for 0-60 d, Cd content in the soil showed a rapid decreasing trend; after 60 d, the enrich- ment ability of the plant to Cd gradually weakened over time; after 75 d of phytore- mediation, the Cd content in the soil decreased greatly, and the remediation effi- ciency was 90.66%. [Conclusion] Ryegrass remediation technology had good reme- diation effect to Cd-contaminated soil.展开更多
[Objective] The aim was to research phytoremediation effects on soils with combined pollution. [Method] With simulation experiment, the test selected plants suitable for phytoremediation in soils polluted with Pb-Cd, ...[Objective] The aim was to research phytoremediation effects on soils with combined pollution. [Method] With simulation experiment, the test selected plants suitable for phytoremediation in soils polluted with Pb-Cd, PAHs, and Pb-Cd-PAHs,respectively and ryegrass was grown to explore phytoremediation on contaminated sites by adjusting bio-availability. [Result] After 70 d growing of ryegrass, the content of available Pb in contaminated soils was 375.26 mg/kg, the content of Cd was 4.9mg/kg after 90 d, and the content of B [a]P was 0.60 mg/kg after 100 d, which were all lower compared with soil limits. [Conclusion] Ryegrass is a suitable plant for phytoremediation.展开更多
In order to thoroughly understand the mechanism Of drought resistance in plants at DNA level, the DNA damage of two ecotypes of reeds (Phragmites communis T.) stressed by PEG 6000 was analyzed by means of fluorescence...In order to thoroughly understand the mechanism Of drought resistance in plants at DNA level, the DNA damage of two ecotypes of reeds (Phragmites communis T.) stressed by PEG 6000 was analyzed by means of fluorescence analysis of DNA unwinding (FADU). The results showed that the residual double strand DNA percentages (dsDNA%) in dune reed (DR) were significantly higher than those in swamp reed (SR) treated with either 20% or 30% PEG 6000. This meant that the DNA of DR was less damaged in comparison with SR. Similarly, DR resisted DNA damage more strongly than SR as reactive oxygen species (ROS) increased by adding ROS producers diethyldithio carbamate (DDC), H2O2 and Fe2+ of different concentrations. Meanwhile, treating PEG stressed SR with ROS scavengers such as dimethyl sulphoxide (DMSO) and ascorbic acid (Vc) resulted in the reduction of DNA damage, suggesting that ROS could cause DNA damage. In addition, the DNA repair for water-stressed reeds indicated that DR repaired DNA damage much faster and more completely. This might be the first indication that drought stress led to DNA damage in plants and that drought resistance of plants was closely related to DNA damage and repair.展开更多
[Objective] To explore a high efficient phytoremediation technology for soil pollution. [Method] Foliage application and root irrigation were carried out to study the influence on amaranth repair efficiency by using c...[Objective] To explore a high efficient phytoremediation technology for soil pollution. [Method] Foliage application and root irrigation were carried out to study the influence on amaranth repair efficiency by using combined treatments of phytohor- mones (IAA, GA3 SA) and chelating agents (EDTA). [Result] The combined treatment increased the biomass of amaranth under 133Cs, 88Sr, Cr stress The 133Cs, 88Sr, Cr enrich- ment in amaranth by root irrigation were obviously higher than that by foliage appli- cation. The phytoextraction efficiency of phytohormones and chelating agents from best to poor was as following: 100 mg/L SA+1.5 mg/kg EDTA, 500 mg/L GA3+1.5 mg/kg EDTA, 100 mg/L IAA+1.5 mg/kg EDTA. [Conclusion] The most appropriate treatment was the combined treatment of 100 mg/L SA+l.5mg/kg EDTA by soil irri- gation, which could make the total absorption doses of 133Cs, 88Sr, Cr per plant achieve the maximum.展开更多
[Objective] This study was conducted to discuss a high efficient phytore- mediation technology for 133Cs pollution.[Method] The effects of 3 exogenous phyto- hormones on the uptake and accumulation of 133Cs in the see...[Objective] This study was conducted to discuss a high efficient phytore- mediation technology for 133Cs pollution.[Method] The effects of 3 exogenous phyto- hormones on the uptake and accumulation of 133Cs in the seedlings of Helianthus annuus L., which is a kind of hyperaccumulator plant, was further studied in the pot experiments. [Result] The results indicated that the absorption, accumulation and translocation capacities of 133Cs of the sunflower plants could be improved signifi- cantly after the application of phytohormones. 133Cs contents were higher in leaves and flowers as compared with stems and roots. The accumulation capacities of phytohormones were in order of SA〉GA〉IAA. [Conclusion] The absorption capacity, translocation factor and bioaccumulation factor of 133Cs were maximum after the展开更多
The protective role of exogenously supplied selenium (Se^6+) on Bechmeria nivea (L.) Gaud (Ramie) subjected to cadmium (Cd) stress was studied in vitro, and the mechanism was discussed by investigating plant ...The protective role of exogenously supplied selenium (Se^6+) on Bechmeria nivea (L.) Gaud (Ramie) subjected to cadmium (Cd) stress was studied in vitro, and the mechanism was discussed by investigating plant growth, malondialdehyde (MDA), activity of antioxidative enzymes and DNA methylation pattern. Plants grown in hydroponic culture were supplied with spraying Se (selenate, 1.2μmol/L) and cadmium (Cd(NO3)2, 0, 3, 6 and 9 mg/L), individually or simultaneously. At low Se spraying levels, SOD activity was increased by 35.34%, 43.18%, 3.63%under 3, 6 or 9 mg/L cadmium contents, POD was increased by 12.45%, 14.14%, 3.27%, and the level of DNA methylation was decreased by 10.70%, 18.18%and 15.59%, respectively. The results confirmed that spraying low Se on ramie leaves could enhance the activity of SOD and POD, and regulate DNA methylation in ramie leaves.展开更多
Targeting of the synthesized polypeptide in the cells is an important research field in modern cell biology. Cowpea trypsin inhibitor (cpti) gene has been modified and a fusion protein gene (sck) was produced by fusin...Targeting of the synthesized polypeptide in the cells is an important research field in modern cell biology. Cowpea trypsin inhibitor (cpti) gene has been modified and a fusion protein gene (sck) was produced by fusing a signal peptide sequence at cpti 5' end and an endoplasm reticulum (ER) retention signal peptide at cpti3' end respectively. The signal peptide can direct the newly synthesized polypeptide into ER, while ER retention signal can make the protein retained in the ER and its derivative protein body. ELISA test indicated that the accumulation level of foreign CpTI protein in sck transgenic tobacco (Nicotiana tabacum L.) was two times higher than cpti transgenic tobaccos and some individuals were four times higher. At the same time, sck transgenic tobacco has a high resistance to Lepidoptera pest due to the increased accumulation level of foreign CpTI protein. The strategy of foreign protein targeting can be used to increase the accumulation level of foreign protein in transgenic plants and can be widely applied to other related research field in plant genetic engineering.展开更多
In this paper, glasshouse experiments were conducted to determine the accumulation, distribution and transformation of DDTs and HCHs by maize under pot culture conditions. The culture soil was spiked with the organic ...In this paper, glasshouse experiments were conducted to determine the accumulation, distribution and transformation of DDTs and HCHs by maize under pot culture conditions. The culture soil was spiked with the organic pollutants and samples were collected in different durations. Analysis of the plants at harvest showed that the selected plant varied widely in their ability to remove and translo- cate DDTs and HCHs from the soil, the bioconcentration factor ranged from 0.004 to 0.027 for the shoot and from 0.036 to 0.097 for the roots, and the translocation factors were lower than 0.1 with variation between DDTs and HCHs, but no signifi- cant differences were observed. DDTs appeared to have accumulated by both pas- sive adsorption and active absorption, p,p'-DDT and p,p'-DDE were the major metabolite and the transformation was mediated by reductive dehalogenation, the affinity of the OCPs for lipids is one of the major factors affecting their uptake and translocation within the plants.展开更多
The pyrolysis of phytoremediated giant reed(Arundo donax)biomass could cause secondary pollution of heavy metals.The stabilization of heavy metals in the pyrolysis process with external materials such as Al2O3,CaCO3,F...The pyrolysis of phytoremediated giant reed(Arundo donax)biomass could cause secondary pollution of heavy metals.The stabilization of heavy metals in the pyrolysis process with external materials such as Al2O3,CaCO3,FeCl3and NaOH,wasstudied.The results showed that37%As and97%Cd in biochar were stabilized when giant reed powder was pyrolyzed at250°Cwith5%Al2O3for2h.Furthermore,59%Pb in biochar was stabilized at400°C with5%CaCO3for1h.Under biochar produced inoptimized pyrolysis conditions,Cd mainly existed in a residual fraction,while Pb and As mainly existed in oxidizable fraction inBCR analysis.In XRD analysis,As was only found in Ca2As2O7;Cd in biochar mainly existed in Cd(AlCl4)2,CdPbO3or CdSO3;and Pb mainly existed as Pb3O2SO4.展开更多
This study investigated the chromium(Cr)detoxification mechanism-induced changes in growth and antioxidant defence enzyme activities in Chrysopogon zizanioides.Plant growth decreased by 36.8%and 45.0%in the shoots and...This study investigated the chromium(Cr)detoxification mechanism-induced changes in growth and antioxidant defence enzyme activities in Chrysopogon zizanioides.Plant growth decreased by 36.8%and 45.0%in the shoots and roots,respectively,in the 50 mg/L Cr treatment.Cr accumulation was higher in root(9807μg/g DW)than in shoots(8730μg/g DW).Photosynthetic pigments and malondialdehyde content increased up to the 30 mg/L Cr treatment,whereas they declined at higher doses.The activity of superoxide dismutase(SOD),catalase(CAT)and peroxidase(POX)were increased significantly with increasing of Cr dose but slightly declined at higher doses.Isozyme banding patterns revealed the expression of multiple bands for SOD,CAT and POX enzymes,and the band intensity decreased at high doses of Cr exposure.These results indicate that higher Cr doses increased the oxidative stress by over production of reactive oxygen species(ROS)in vetiver that had potential tolerance mechanism to Cr as evidenced by enhanced level of antioxidative enzymes,photosynthetic pigments,MDA contents.Therefore,vetiver has evolved a mechanism for detoxification and accumulates higher concentration of toxic Cr.This study provides a better understanding of how vetiver detoxifies Cr.展开更多
There has been carried out a comparative research, which allow us to determine the quantities and the central points of accumulation ofPb, Cu, Zn and Cd in the vegetative and reproductive organs of the four sorghum va...There has been carried out a comparative research, which allow us to determine the quantities and the central points of accumulation ofPb, Cu, Zn and Cd in the vegetative and reproductive organs of the four sorghum varieties (technical sorghtan, sugar sorghum, sudan grass and grain sorghnm), as well as to ascertain the possibilities for their growth in soils contaminated with heavy metals and their application for phytoremediation purposes. The experimental plots were situated at different distances (0.1 and 15.0 kin) from the source of pollution-the Non-Ferrous Metal Works near Plovdiv, Bulgaria. On reaching commercial ripeness, the crops were gathered and the concentrations of Pb, Cu, Zn and Cd in their different parts-roots, stems, leaves and gains-were determined through dry mineralization. To determine the heavy metal content in the samples, ICP was used. A clearly distinguished trend exists which describes the accumulation of heavy metals within the vegetative and reproductive organs of the studied crops. Sudan grass and technical sorghum accumulated larger heavy metal quantities compared to sugar sorghum and grain sorghum, as the majority of the heavy metals was retained by the roots and a very small amount was translocated to epigeous parts. The depots for accumulation were in the following order: roots 〉 leaves 〉 stems 〉 grains. The studied crops can be related to metal-tolerant crops and can be cultivated on softs which are of low, medium or high contamination with lead, zinc and cadmium, as they do not exhibit a tendency of accumulating these elements in grains at levels above the maximum permissible concentrations for fodder. The selective accumulation of Pb, Cu, Zn and Cd in the roots and the possibility to remove the root-remains makes technical sorghum, sugar sorghum and Sudan grass extremely suitable for phytoremediation purposes. The possible use of grains for animal food guarantees the economic expedience upon the selection of these crops.展开更多
[ Objective] This study was to research the treatment effect of different media in undercurrent wetland on contamination, so as to pro- vide reference for rehabitating water body of river along small towns. [ Method ]...[ Objective] This study was to research the treatment effect of different media in undercurrent wetland on contamination, so as to pro- vide reference for rehabitating water body of river along small towns. [ Method ] Three different media of gravel, cobblestone and shale were used to rehabilitate water quality of contaminated river. [ Result ] Gravel, cobblestone and shale all performed well in removing TN, TP and CODw,, in contaminated water, of which gravel stuffed undercurrent wetland run best, averagely removing 49.4% TN, 34.7% and 48. 5% COD~, respectively. [ Conclusion] Undercurrent constructed wetland can effectively improve the water quality of contaminated river, and it is cheaper in cost and simpler in operation, thus suitable for generalizing in small towns of China.展开更多
Phosphate was found to have neither influence on Cd transformation nor effect on plant Cd uptake in three Cd-amended upland soils.However,on submerged red earth,high phosphate dressing inhibited the transformation of ...Phosphate was found to have neither influence on Cd transformation nor effect on plant Cd uptake in three Cd-amended upland soils.However,on submerged red earth,high phosphate dressing inhibited the transformation of Cd from exchangeable fraction to other lower-available ones.Cadmium uptake by rice plants increased simultaneously with increasing phosphate supply though plant resistance to Cd also increased at high phosphate level.Application of phosphate as an amendment for Cd-contaminated soil was therefore not recommended in view of the increasing influx of Cd into food chain especially on flooded soils.展开更多
基金Project(40973055) supported by the National Natural Science Foundation of ChinaProject(U0833004) supported by the NSFC-Guangdong Joint Foundation of China
文摘Three bacterial endophytes of Sedum alfredii, VI8L2, II8L4 and VI8R2, were examined for promoting soil Zn bioavailability and Zn accumulation in S. alfredii. Results showed that three strains were re-introduced into S. alfredii rhizosphere soils under Zn stress and resulted in better plant growth, as roots biomass increased from 80% to 525% and shoot biomass from 11% to 47% compared with the uninoculated ones. Strains IVsLz, II8L4 and IVsR2 significantly increased shoot and root Zn concentrations in the ZnCO3 contaminated soil. Inoculation with strain IVsL2 resulted in 44% and 39% higher shoot and root Zn concentrations, while strain IV8R2 significantly decreased shoot Zn concentration in the Zn3(PO4)2 contaminated soils. In the aged contaminated soil, isolates IVsL2, IIsL4 and IVsR2 significantly increased root Zn concentration, but decreased shoot Zn concentration of Sedum alfredii. It suggested that endophytes might be used for enhancing phytoextraction efficiency.
基金Project (2012BAC09B04) supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of ChinaProject (2010-277-027) supported by Science and Technology Foundation of Environmental Protection in Hunan Province,ChinaProject (2011SK3262) supported by Science and Technology Planning of Hunan Province,China
文摘The effects of five amendments such as acetic acid(AA), citric acid (CA), ethylenediamine tetraacetic acid (EDTA), sepiolite and phosphogypsum on growth and metal uptake of giant reed (Arundo donax L.) grown on soil contaminated by arsenic (As), cadmium (Cd) and lead (Pb) were studied. The results showed that the shoot biomass of giant reed was enhanced by 24.8% and 15.0%, while superoxide mutase and catalase activities slightly varied when adding 5.0 mmol/kg CA and 2.5 mol/kg EDTA to soil as compared to the control, respectively. The concentrations of As, Cd and Pb in shoots were remarkably increased by the addition of 2.5 mmol/kg AA and CA, 5.0 mmol/kg EDTA, and 4.0 g/kg sepiolite as compared to the control. The accumulations of As and Cd were also significantly enhanced in the above condition, while the shoot Pb accumulation was noticeably enhanced by amending with 4.0 g/kg sepiolite and 8.0 g/kg phosphogysum, respectively. The results suggested that AA, CA and sepiolite could be used as optimum soil amendments for giant reed remediation system.
文摘Phytoremediation is an efficient and economic ecological technology. It includes phytostabilization, phytovolatilization, and plant absorption. In the research, status quo and progress of Phytostabilization and plant absorption in soils polluted with heavy metals in metal mines were summarized, including the characteristics and status quo of phytoremediation and selection method of hyperaccumulator. In addition, further research was proposed as well.
基金Supported by Major State Basic Research Development Program(973 Program) (2007CB407306)National Natural Science Foun-dation of China (50908159)~~
文摘[Objective] The aim was to study the phytoremediation of heavy metal pollution in river sediment by Medicago sativa L.,so as to provide reliable references for the phytoremediation of heavy metal pollution in river sediment.[Method] The air-dried,screened and mixed sediment was put in rectangular PVC box(0.6 m×0.5 m×0.4 m) with seepage vent at the bottom,and the water holding capacity(WHC) of sediment was kept at 30%-60% by deionized water.The seeds of Medicago sativa L.were sown in April 2010,and seedlings were thinned after 7 d.Samples were collected from rhizosphere soil every 30 d,and were used to determine the content of heavy metals,bacteria quantity and enzyme activity in sediment.In addition,the accumulation of heavy metals in the roots,stems and leaves of plant was measured after harvest in October.[Result] Different parts of Medicago sativa L.varied in accumulation capacity to different heavy metals.The accumulation amount of Zn in Medicago sativa L.was the highest,especially in roots.Meanwhile,the accumulation amount of heavy metals like Ni,Cr,Cu and Pb in roots was higher than that of stems and leaves.In contrast,Mn was mainly accumulated in leaves and its amount accounted for 42.47% of the total amount in plant.Besides,the accumulation amount of all heavy metals was the lowest in stems.Ni,Cr,Cu and Pb could be degraded more effectively than Mn,and increasing the planting time and sowing times of crop was beneficial to the degradation of heavy metals.After planted Medicago sativa L.,the quantity of microorganisms in sediment went up obviously,and dehydrogenase activity also showed an increaseing trend.[Conclusion] Medicago sativa L.has certain restoring effect on Zn,Ni,Cr,Cu and Pb,and could be used to restore heavy metal pollution in river sediment.
基金Supported by National Science Foundation of China(30560032)Guangxi Key Laboratory Foundation (0702k023)~~
文摘[Objective] The research aimed to study the response and accumulation characteristics of Cd in Polygonum pubescens Bl.[Method] Taking Hoagland nutritional solution as the culture substrate,eight kinds of Cd concentrations (0,25,50,100,200,500,800,1 000 mg/L) were set up.[Result] Under low concentrations of Cd (25 and 50 mg/L),the biomass of P.pubescens had no significant difference with CK (P0.05).Under all the test concentrations of Cd,Cd content in the roots and shoots of P.pubescens exceeded 100 mg/kg and the enrichment coefficients of Cd were over 1.With the increasing of Cd concentration,Cd content and Cd accumulation amount in P.pubescens increased significantly.When Cd concentration exceeded 50 mg/L,translocation capacity coefficient was greater than 1.[Conclusion] Polygonum pubescens has high tolerance and accumulation capacity of Cd,and it may has some potential on the phytoremediation of Cd-contaminated soil.
基金Supported by the Prospective Research Project of Industry-University-Research Cooperation in Jiangsu Province(BY2014037-21)~~
文摘[Objective] The remediation effect of the plant to Cd-contaminated soil was studied. [Method] By taking simulation test and field test, the ryegrass (Lolium perenne L.) was planted, and the remediation effect of the plant to contaminated sites was studied. [Result] The ryegrass was planted in the eluotropic soil for 0-60 d, Cd content in the soil showed a rapid decreasing trend; after 60 d, the enrich- ment ability of the plant to Cd gradually weakened over time; after 75 d of phytore- mediation, the Cd content in the soil decreased greatly, and the remediation effi- ciency was 90.66%. [Conclusion] Ryegrass remediation technology had good reme- diation effect to Cd-contaminated soil.
基金Supported by Unified Research with Industry-University-Research Cooperation(BY2014037-21)~~
文摘[Objective] The aim was to research phytoremediation effects on soils with combined pollution. [Method] With simulation experiment, the test selected plants suitable for phytoremediation in soils polluted with Pb-Cd, PAHs, and Pb-Cd-PAHs,respectively and ryegrass was grown to explore phytoremediation on contaminated sites by adjusting bio-availability. [Result] After 70 d growing of ryegrass, the content of available Pb in contaminated soils was 375.26 mg/kg, the content of Cd was 4.9mg/kg after 90 d, and the content of B [a]P was 0.60 mg/kg after 100 d, which were all lower compared with soil limits. [Conclusion] Ryegrass is a suitable plant for phytoremediation.
文摘In order to thoroughly understand the mechanism Of drought resistance in plants at DNA level, the DNA damage of two ecotypes of reeds (Phragmites communis T.) stressed by PEG 6000 was analyzed by means of fluorescence analysis of DNA unwinding (FADU). The results showed that the residual double strand DNA percentages (dsDNA%) in dune reed (DR) were significantly higher than those in swamp reed (SR) treated with either 20% or 30% PEG 6000. This meant that the DNA of DR was less damaged in comparison with SR. Similarly, DR resisted DNA damage more strongly than SR as reactive oxygen species (ROS) increased by adding ROS producers diethyldithio carbamate (DDC), H2O2 and Fe2+ of different concentrations. Meanwhile, treating PEG stressed SR with ROS scavengers such as dimethyl sulphoxide (DMSO) and ascorbic acid (Vc) resulted in the reduction of DNA damage, suggesting that ROS could cause DNA damage. In addition, the DNA repair for water-stressed reeds indicated that DR repaired DNA damage much faster and more completely. This might be the first indication that drought stress led to DNA damage in plants and that drought resistance of plants was closely related to DNA damage and repair.
基金Supported by the Plan for the National Defense Basic Scientific Research of the State Administration of ScienceTechnology and Industry for National Defense of China(b312011)~~
文摘[Objective] To explore a high efficient phytoremediation technology for soil pollution. [Method] Foliage application and root irrigation were carried out to study the influence on amaranth repair efficiency by using combined treatments of phytohor- mones (IAA, GA3 SA) and chelating agents (EDTA). [Result] The combined treatment increased the biomass of amaranth under 133Cs, 88Sr, Cr stress The 133Cs, 88Sr, Cr enrich- ment in amaranth by root irrigation were obviously higher than that by foliage appli- cation. The phytoextraction efficiency of phytohormones and chelating agents from best to poor was as following: 100 mg/L SA+1.5 mg/kg EDTA, 500 mg/L GA3+1.5 mg/kg EDTA, 100 mg/L IAA+1.5 mg/kg EDTA. [Conclusion] The most appropriate treatment was the combined treatment of 100 mg/L SA+l.5mg/kg EDTA by soil irri- gation, which could make the total absorption doses of 133Cs, 88Sr, Cr per plant achieve the maximum.
文摘[Objective] This study was conducted to discuss a high efficient phytore- mediation technology for 133Cs pollution.[Method] The effects of 3 exogenous phyto- hormones on the uptake and accumulation of 133Cs in the seedlings of Helianthus annuus L., which is a kind of hyperaccumulator plant, was further studied in the pot experiments. [Result] The results indicated that the absorption, accumulation and translocation capacities of 133Cs of the sunflower plants could be improved signifi- cantly after the application of phytohormones. 133Cs contents were higher in leaves and flowers as compared with stems and roots. The accumulation capacities of phytohormones were in order of SA〉GA〉IAA. [Conclusion] The absorption capacity, translocation factor and bioaccumulation factor of 133Cs were maximum after the
基金Project(41271332)supported by the National Natural Science Foundation of ChinaProject(11JJ2031)supported by the Natural Science Foundation of Hunan Province,China
文摘The protective role of exogenously supplied selenium (Se^6+) on Bechmeria nivea (L.) Gaud (Ramie) subjected to cadmium (Cd) stress was studied in vitro, and the mechanism was discussed by investigating plant growth, malondialdehyde (MDA), activity of antioxidative enzymes and DNA methylation pattern. Plants grown in hydroponic culture were supplied with spraying Se (selenate, 1.2μmol/L) and cadmium (Cd(NO3)2, 0, 3, 6 and 9 mg/L), individually or simultaneously. At low Se spraying levels, SOD activity was increased by 35.34%, 43.18%, 3.63%under 3, 6 or 9 mg/L cadmium contents, POD was increased by 12.45%, 14.14%, 3.27%, and the level of DNA methylation was decreased by 10.70%, 18.18%and 15.59%, respectively. The results confirmed that spraying low Se on ramie leaves could enhance the activity of SOD and POD, and regulate DNA methylation in ramie leaves.
文摘Targeting of the synthesized polypeptide in the cells is an important research field in modern cell biology. Cowpea trypsin inhibitor (cpti) gene has been modified and a fusion protein gene (sck) was produced by fusing a signal peptide sequence at cpti 5' end and an endoplasm reticulum (ER) retention signal peptide at cpti3' end respectively. The signal peptide can direct the newly synthesized polypeptide into ER, while ER retention signal can make the protein retained in the ER and its derivative protein body. ELISA test indicated that the accumulation level of foreign CpTI protein in sck transgenic tobacco (Nicotiana tabacum L.) was two times higher than cpti transgenic tobaccos and some individuals were four times higher. At the same time, sck transgenic tobacco has a high resistance to Lepidoptera pest due to the increased accumulation level of foreign CpTI protein. The strategy of foreign protein targeting can be used to increase the accumulation level of foreign protein in transgenic plants and can be widely applied to other related research field in plant genetic engineering.
基金Supported by the Youth Innovation Fund of Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences(2009QNJJN01)the Science and Technology Innovation Fund of Inner Mongolia(2011CXJJN01)the Application Technology Research and Development Program from Department of Science and Technology of Inner Mongolia(20110516)~~
文摘In this paper, glasshouse experiments were conducted to determine the accumulation, distribution and transformation of DDTs and HCHs by maize under pot culture conditions. The culture soil was spiked with the organic pollutants and samples were collected in different durations. Analysis of the plants at harvest showed that the selected plant varied widely in their ability to remove and translo- cate DDTs and HCHs from the soil, the bioconcentration factor ranged from 0.004 to 0.027 for the shoot and from 0.036 to 0.097 for the roots, and the translocation factors were lower than 0.1 with variation between DDTs and HCHs, but no signifi- cant differences were observed. DDTs appeared to have accumulated by both pas- sive adsorption and active absorption, p,p'-DDT and p,p'-DDE were the major metabolite and the transformation was mediated by reductive dehalogenation, the affinity of the OCPs for lipids is one of the major factors affecting their uptake and translocation within the plants.
基金Projects(21577176,41271330) supported by the National Natural Science Foundation of China
文摘The pyrolysis of phytoremediated giant reed(Arundo donax)biomass could cause secondary pollution of heavy metals.The stabilization of heavy metals in the pyrolysis process with external materials such as Al2O3,CaCO3,FeCl3and NaOH,wasstudied.The results showed that37%As and97%Cd in biochar were stabilized when giant reed powder was pyrolyzed at250°Cwith5%Al2O3for2h.Furthermore,59%Pb in biochar was stabilized at400°C with5%CaCO3for1h.Under biochar produced inoptimized pyrolysis conditions,Cd mainly existed in a residual fraction,while Pb and As mainly existed in oxidizable fraction inBCR analysis.In XRD analysis,As was only found in Ca2As2O7;Cd in biochar mainly existed in Cd(AlCl4)2,CdPbO3or CdSO3;and Pb mainly existed as Pb3O2SO4.
基金Project(41771512)supported by the National Natural Science Foundation of ChinaProject(2018RS3004)supported by Hunan Science&Technology Innovation Program,China
文摘This study investigated the chromium(Cr)detoxification mechanism-induced changes in growth and antioxidant defence enzyme activities in Chrysopogon zizanioides.Plant growth decreased by 36.8%and 45.0%in the shoots and roots,respectively,in the 50 mg/L Cr treatment.Cr accumulation was higher in root(9807μg/g DW)than in shoots(8730μg/g DW).Photosynthetic pigments and malondialdehyde content increased up to the 30 mg/L Cr treatment,whereas they declined at higher doses.The activity of superoxide dismutase(SOD),catalase(CAT)and peroxidase(POX)were increased significantly with increasing of Cr dose but slightly declined at higher doses.Isozyme banding patterns revealed the expression of multiple bands for SOD,CAT and POX enzymes,and the band intensity decreased at high doses of Cr exposure.These results indicate that higher Cr doses increased the oxidative stress by over production of reactive oxygen species(ROS)in vetiver that had potential tolerance mechanism to Cr as evidenced by enhanced level of antioxidative enzymes,photosynthetic pigments,MDA contents.Therefore,vetiver has evolved a mechanism for detoxification and accumulates higher concentration of toxic Cr.This study provides a better understanding of how vetiver detoxifies Cr.
文摘There has been carried out a comparative research, which allow us to determine the quantities and the central points of accumulation ofPb, Cu, Zn and Cd in the vegetative and reproductive organs of the four sorghum varieties (technical sorghtan, sugar sorghum, sudan grass and grain sorghnm), as well as to ascertain the possibilities for their growth in soils contaminated with heavy metals and their application for phytoremediation purposes. The experimental plots were situated at different distances (0.1 and 15.0 kin) from the source of pollution-the Non-Ferrous Metal Works near Plovdiv, Bulgaria. On reaching commercial ripeness, the crops were gathered and the concentrations of Pb, Cu, Zn and Cd in their different parts-roots, stems, leaves and gains-were determined through dry mineralization. To determine the heavy metal content in the samples, ICP was used. A clearly distinguished trend exists which describes the accumulation of heavy metals within the vegetative and reproductive organs of the studied crops. Sudan grass and technical sorghum accumulated larger heavy metal quantities compared to sugar sorghum and grain sorghum, as the majority of the heavy metals was retained by the roots and a very small amount was translocated to epigeous parts. The depots for accumulation were in the following order: roots 〉 leaves 〉 stems 〉 grains. The studied crops can be related to metal-tolerant crops and can be cultivated on softs which are of low, medium or high contamination with lead, zinc and cadmium, as they do not exhibit a tendency of accumulating these elements in grains at levels above the maximum permissible concentrations for fodder. The selective accumulation of Pb, Cu, Zn and Cd in the roots and the possibility to remove the root-remains makes technical sorghum, sugar sorghum and Sudan grass extremely suitable for phytoremediation purposes. The possible use of grains for animal food guarantees the economic expedience upon the selection of these crops.
文摘[ Objective] This study was to research the treatment effect of different media in undercurrent wetland on contamination, so as to pro- vide reference for rehabitating water body of river along small towns. [ Method ] Three different media of gravel, cobblestone and shale were used to rehabilitate water quality of contaminated river. [ Result ] Gravel, cobblestone and shale all performed well in removing TN, TP and CODw,, in contaminated water, of which gravel stuffed undercurrent wetland run best, averagely removing 49.4% TN, 34.7% and 48. 5% COD~, respectively. [ Conclusion] Undercurrent constructed wetland can effectively improve the water quality of contaminated river, and it is cheaper in cost and simpler in operation, thus suitable for generalizing in small towns of China.
文摘Phosphate was found to have neither influence on Cd transformation nor effect on plant Cd uptake in three Cd-amended upland soils.However,on submerged red earth,high phosphate dressing inhibited the transformation of Cd from exchangeable fraction to other lower-available ones.Cadmium uptake by rice plants increased simultaneously with increasing phosphate supply though plant resistance to Cd also increased at high phosphate level.Application of phosphate as an amendment for Cd-contaminated soil was therefore not recommended in view of the increasing influx of Cd into food chain especially on flooded soils.