On base of the content of Pb in the soil under different land use patterns in Lanping Lead-zinc mining area,Yunnan in southwest China,the root morphology and leaf traits of maize in different concentration Pb(20,40,60...On base of the content of Pb in the soil under different land use patterns in Lanping Lead-zinc mining area,Yunnan in southwest China,the root morphology and leaf traits of maize in different concentration Pb(20,40,60,80,100,150,200,500,1000,2000,3000 mg/L)were analyzed.The results showed that maize germination rate,germination vigor and growth index decreased with the increase of Pb concentration.The root length,surface area of maize increased by 0.21%-81.58%,8.99%-73.43%,1.50%-77.37%,respectively,under 20-500 mg/L Pb concentration.However,these parameters under 1000-3000 mg/L Pb concentration decreased by 37.86%-553.54%,44.99%-766.16%,55.99%-92.81%,respectively,and these lowest value appeared in 3000 mg/L Pb treatment.The root volume of maize increased by 4.57%-89.25%in 20-80 mg/L Pb concentration,and it decreased with the increase of Pb concentration when the Pb concentration was higher than 80 mg/L and decreased by 94.13%in 3000 mg/L Pb.The root surface area and length of 0.50-1.00 diameter class were higher than those of other diameter classes,and these value of maize under 500 mg/L Pb were higher than those of other concentrations.The length and perimeter of maize leaves with the highest value of 220.36 and 962.68 mm,respectively appeared in 60 mg/L Pb treatment.The leaf width and area of maize with the highest value of 15.68 mm and 2448.31 mm^(2),respectively,appeared in 40 mg/L Pb treatment,which indicated that the leaf traits of maize were promoted by low concentration Pb and inhibited by high concentration Pb.展开更多
In rice,high concentration of lead(Pb)can cause phyto-toxicity affecting several physiological functions.Cultivation of rice varieties that are resistant to Pb-induced oxidative stress is an important management strat...In rice,high concentration of lead(Pb)can cause phyto-toxicity affecting several physiological functions.Cultivation of rice varieties that are resistant to Pb-induced oxidative stress is an important management strategy in Pb-contaminated soils.In the current study,we evaluated four different rice cultivars for their response to Pb-induced stress.Three japonica type cultivars X-Jigna,Ediget,and Furat,and one Indica type cultivar Amber 33 were grown in soil containing different Pb concentrations(0 mM,0.6 mM,and 1.2 mM).The soil was treated with 0 mM or 0.6 mM or 1.2 mM Pb solution one month prior to rice seedling transplantation.Thereafter,four-week-old rice seedlings were transplanted into the treated soil and their responses were observed until maturity.The data revealed that a highest concentration of Pb(1.2 mM)induced significant reduction in agronomic traits such as plant height,number of tillers per plant,number of panicles per plant,and number of spikelets per panicle in all the rice cultivars.However,least reduction in the agronomic traits was observed in X-Jigna,whereas the highest reduction in the agronomic traits was observed in Ediget.Antioxidant activity of catalase(CAT),peroxidase(POD),polyphenol oxidase(PPO),and superoxide dismutase(SOD),was evaluated along with the accumulation of superoxide ions(O2.-),protein,proline,chlorophyll,sucrose,glucose,and fructose contents in all the rice cultivars.A significant increase in antioxidant activity and in the accumulation of proline and sucrose contents with the least reduction in the chlorophyll and protein contents was observed in X-Jigna suggesting that X-Jigna is the most tolerant among all the rice cultivars tested against Pb-stress.On the other hand,non-significant and slightly significant increase in the antioxidant activity,less accumulation of proline and sucrose contents,and higher reduction in the chlorophyll and protein contents was observed in Ediget,which further suggest that Ediget is the most susceptible rice cultivar to Pb-stress.In addition,the other rice cultivars Furat and Amber 33,were found to be moderately tolerant to Pb-induced oxidative stress.In summary,our results suggest that tolerance to Pb-induced oxidative stress would be a result of a synergetic action of both enzymatic and non-enzymatic antioxidant systems,leading to a balanced redox status in rice.展开更多
The symmetrical push-pull fatigue tests at strain amplitude of 2×10~3 with different slip orientation of Al single crystals,were carried out at room temperature in air.The peak stresses of various cycles were mea...The symmetrical push-pull fatigue tests at strain amplitude of 2×10~3 with different slip orientation of Al single crystals,were carried out at room temperature in air.The peak stresses of various cycles were measured and the stress-strain hysteresis loops for selected cy- cles were recorded.The energy losses.friction stresses,back stresses and shape展开更多
Larix olgensis A. Henry(Changbai larch) is a productive commercial species and good candidate for afforestation in northeast China. It is widely planted in lead-stressed soils which can induce oxidative damage in this...Larix olgensis A. Henry(Changbai larch) is a productive commercial species and good candidate for afforestation in northeast China. It is widely planted in lead-stressed soils which can induce oxidative damage in this plant. Increasing tolerance to lead(Pb) stress is therefore of keen interest. A greenhouse experiment was conducted to identify the biomass, physiological responses and Pb accumulation of L. olgensis seedlings to Pb stress under succinic acid(SA) application and to explore the interaction of exogenous SA applications and stress resistance. L. olgensis seedlings were planted in Pb-stressed or unstressed haplic cambisols in pots. In Pb-contaminated soils the seedlings were treated daily with concentrations of SA solutions at a rate approximately equivalent to 0, 0.04,0.2, 1.0, or 2.0 mmol kg-1of soil for 10, 20, and 30 days,respectively. Pb treatment induced damage in the seedlings and led to the inhibition of biomass accumulation in roots,stems and leaves, and a rise in Pb accumulation in fine roots and leaves. Malondialdehyde(MDA) content and electrolyte leakage in leaves significantly increased while peroxidase(POD) activities, soluble protein and photosynthetic pigment contents in leaves were all reduced.Physiological toxicity was promoted with increasing Pb treatment times. When Pb-stressed seedlings were exposed to SA(especially 10.0 mmol L-1 over 20 days), the physiological responses for Pb-only were reversed and the biomass of roots, stems, and leaves dramatically increased.SA facilitated Pb uptake in fine roots and leaves but more Pb accumulated in fine roots. The results demonstrate that exogenous SA alleviates Pb-induced oxidative injuries and improves the tolerance of L. olgensis seedlings to Pb stress.展开更多
Two maize inbred lines, the foundation genotype Y478 and its derived line Z58, are widely used to breed novel maize cultivars in China, but little is known about which traits confer Z58 with superior drought tolerance...Two maize inbred lines, the foundation genotype Y478 and its derived line Z58, are widely used to breed novel maize cultivars in China, but little is known about which traits confer Z58 with superior drought tolerance and yield. In the present study, responses in growth traits, photosynthetic parameters, chlorophyll fluorescence and leaf micromorphological characteristics were evaluated in Y478 and Z58 subjected to water-deficit stress induced by PEG 6000. The derived line Z58 showed greater drought tolerance than Y478, which was associated with higher leaf relative water content (RWC), root efficiency, and strong growth recovery. Z58 showed a higher stomatal density and stomatal area under the non-stressed condition;in these traits, both genotypes showed a similar decreasing trend with increased severity of water-deficit stress. In addition, the stomatal size of Y478 declined significantly. These micromorphological differences between the two lines were consistent with changes in physiological parameters, which may contribute to the enhanced capability for growth recovery in Z58. A non-linear response of Fv/Fm to leaf RWC was observed, and Fv/Fm decreased rapidly with a further gradual decline of leaf RWC. The relationship between other chlorophyll fluorescence parameters (photochemical quenching and electron transport rate) and RWC is also discussed.展开更多
基金Basic Research in Yunnan Local Colleges and Universities(2017FH001-026,2018FH001-004)the National Natural Science Foundation of China(42167009,31300349)International Joint Innovation Team for Yunnan Plateau Lakes and Great Lakes of North America which is sponsored by Yunnan Provincial Education Department(to XC),and Scientific and Technological Innovation team Project of Agricultural Resources Utilization of Kunming University.
文摘On base of the content of Pb in the soil under different land use patterns in Lanping Lead-zinc mining area,Yunnan in southwest China,the root morphology and leaf traits of maize in different concentration Pb(20,40,60,80,100,150,200,500,1000,2000,3000 mg/L)were analyzed.The results showed that maize germination rate,germination vigor and growth index decreased with the increase of Pb concentration.The root length,surface area of maize increased by 0.21%-81.58%,8.99%-73.43%,1.50%-77.37%,respectively,under 20-500 mg/L Pb concentration.However,these parameters under 1000-3000 mg/L Pb concentration decreased by 37.86%-553.54%,44.99%-766.16%,55.99%-92.81%,respectively,and these lowest value appeared in 3000 mg/L Pb treatment.The root volume of maize increased by 4.57%-89.25%in 20-80 mg/L Pb concentration,and it decreased with the increase of Pb concentration when the Pb concentration was higher than 80 mg/L and decreased by 94.13%in 3000 mg/L Pb.The root surface area and length of 0.50-1.00 diameter class were higher than those of other diameter classes,and these value of maize under 500 mg/L Pb were higher than those of other concentrations.The length and perimeter of maize leaves with the highest value of 220.36 and 962.68 mm,respectively appeared in 60 mg/L Pb treatment.The leaf width and area of maize with the highest value of 15.68 mm and 2448.31 mm^(2),respectively,appeared in 40 mg/L Pb treatment,which indicated that the leaf traits of maize were promoted by low concentration Pb and inhibited by high concentration Pb.
基金a grant from the Next-Generation BioGreen 21 Program(SSAC,Grant No.PJ01342501),Rural Development Administration,Republic of Korea.
文摘In rice,high concentration of lead(Pb)can cause phyto-toxicity affecting several physiological functions.Cultivation of rice varieties that are resistant to Pb-induced oxidative stress is an important management strategy in Pb-contaminated soils.In the current study,we evaluated four different rice cultivars for their response to Pb-induced stress.Three japonica type cultivars X-Jigna,Ediget,and Furat,and one Indica type cultivar Amber 33 were grown in soil containing different Pb concentrations(0 mM,0.6 mM,and 1.2 mM).The soil was treated with 0 mM or 0.6 mM or 1.2 mM Pb solution one month prior to rice seedling transplantation.Thereafter,four-week-old rice seedlings were transplanted into the treated soil and their responses were observed until maturity.The data revealed that a highest concentration of Pb(1.2 mM)induced significant reduction in agronomic traits such as plant height,number of tillers per plant,number of panicles per plant,and number of spikelets per panicle in all the rice cultivars.However,least reduction in the agronomic traits was observed in X-Jigna,whereas the highest reduction in the agronomic traits was observed in Ediget.Antioxidant activity of catalase(CAT),peroxidase(POD),polyphenol oxidase(PPO),and superoxide dismutase(SOD),was evaluated along with the accumulation of superoxide ions(O2.-),protein,proline,chlorophyll,sucrose,glucose,and fructose contents in all the rice cultivars.A significant increase in antioxidant activity and in the accumulation of proline and sucrose contents with the least reduction in the chlorophyll and protein contents was observed in X-Jigna suggesting that X-Jigna is the most tolerant among all the rice cultivars tested against Pb-stress.On the other hand,non-significant and slightly significant increase in the antioxidant activity,less accumulation of proline and sucrose contents,and higher reduction in the chlorophyll and protein contents was observed in Ediget,which further suggest that Ediget is the most susceptible rice cultivar to Pb-stress.In addition,the other rice cultivars Furat and Amber 33,were found to be moderately tolerant to Pb-induced oxidative stress.In summary,our results suggest that tolerance to Pb-induced oxidative stress would be a result of a synergetic action of both enzymatic and non-enzymatic antioxidant systems,leading to a balanced redox status in rice.
文摘The symmetrical push-pull fatigue tests at strain amplitude of 2×10~3 with different slip orientation of Al single crystals,were carried out at room temperature in air.The peak stresses of various cycles were measured and the stress-strain hysteresis loops for selected cy- cles were recorded.The energy losses.friction stresses,back stresses and shape
基金financially supported by the National Natural Science Foundation of China(31370613)the Fundamental Research Funds for the Central Universities(2572017CA03)
文摘Larix olgensis A. Henry(Changbai larch) is a productive commercial species and good candidate for afforestation in northeast China. It is widely planted in lead-stressed soils which can induce oxidative damage in this plant. Increasing tolerance to lead(Pb) stress is therefore of keen interest. A greenhouse experiment was conducted to identify the biomass, physiological responses and Pb accumulation of L. olgensis seedlings to Pb stress under succinic acid(SA) application and to explore the interaction of exogenous SA applications and stress resistance. L. olgensis seedlings were planted in Pb-stressed or unstressed haplic cambisols in pots. In Pb-contaminated soils the seedlings were treated daily with concentrations of SA solutions at a rate approximately equivalent to 0, 0.04,0.2, 1.0, or 2.0 mmol kg-1of soil for 10, 20, and 30 days,respectively. Pb treatment induced damage in the seedlings and led to the inhibition of biomass accumulation in roots,stems and leaves, and a rise in Pb accumulation in fine roots and leaves. Malondialdehyde(MDA) content and electrolyte leakage in leaves significantly increased while peroxidase(POD) activities, soluble protein and photosynthetic pigment contents in leaves were all reduced.Physiological toxicity was promoted with increasing Pb treatment times. When Pb-stressed seedlings were exposed to SA(especially 10.0 mmol L-1 over 20 days), the physiological responses for Pb-only were reversed and the biomass of roots, stems, and leaves dramatically increased.SA facilitated Pb uptake in fine roots and leaves but more Pb accumulated in fine roots. The results demonstrate that exogenous SA alleviates Pb-induced oxidative injuries and improves the tolerance of L. olgensis seedlings to Pb stress.
文摘Two maize inbred lines, the foundation genotype Y478 and its derived line Z58, are widely used to breed novel maize cultivars in China, but little is known about which traits confer Z58 with superior drought tolerance and yield. In the present study, responses in growth traits, photosynthetic parameters, chlorophyll fluorescence and leaf micromorphological characteristics were evaluated in Y478 and Z58 subjected to water-deficit stress induced by PEG 6000. The derived line Z58 showed greater drought tolerance than Y478, which was associated with higher leaf relative water content (RWC), root efficiency, and strong growth recovery. Z58 showed a higher stomatal density and stomatal area under the non-stressed condition;in these traits, both genotypes showed a similar decreasing trend with increased severity of water-deficit stress. In addition, the stomatal size of Y478 declined significantly. These micromorphological differences between the two lines were consistent with changes in physiological parameters, which may contribute to the enhanced capability for growth recovery in Z58. A non-linear response of Fv/Fm to leaf RWC was observed, and Fv/Fm decreased rapidly with a further gradual decline of leaf RWC. The relationship between other chlorophyll fluorescence parameters (photochemical quenching and electron transport rate) and RWC is also discussed.
