The physiological responses of Paspalum vaginatum Sw. to Cd stress and its Cd accumulation characteristics were studied by investigating the effects of different concentrations of Cd on the growth, root vigor, leaf me...The physiological responses of Paspalum vaginatum Sw. to Cd stress and its Cd accumulation characteristics were studied by investigating the effects of different concentrations of Cd on the growth, root vigor, leaf membrane permeability, membrane lipid peroxidation, protective enzyme activity and Cd accumulation of P. vaginatum. When the Cd concentration was over 50.00 mg/kg, with the increased Cd concentration, the CAT activity declined significantly, the synergistic effect between SOD and CAT was weakened, the MDA content increased greatly, and the root vigor decreased, leading to inhibited growth of P. vaginatum. When the Cd concentration was in the range of 0-50 mg/kg, the root vigor of P. vaginatum did not decline obviously, the activity of protective enzymes （SOD and CAT） was enhanced, and the MDA accumulation and cell membrane permeability did not increase significantly, thus the damage of Cd to P. vaginatum was lighter. Roots of P. vaginatum showed strong enrichment capacity for Cd. When the Cd concentration was up to 200.00 mg/kg, the Cd contents in shoot and root of P. vaginatum reached 39.15 and 1 097.38 mg/kg, respectively. It suggests that in the concentration range of 0-50.00 mg/kg, P. vaginatum can make effective responses to Cd stress and grow normally, and it can be planted as a candidate material to remediate Cd-contaminated soil.展开更多
To investigate the correlation and difference between Paspalum notatum’s leaf and root under drought adversity,this study tested the physiological responses of wild Paspalum notatum’s leaf and root under 0(CK),1,3,5...To investigate the correlation and difference between Paspalum notatum’s leaf and root under drought adversity,this study tested the physiological responses of wild Paspalum notatum’s leaf and root under 0(CK),1,3,5,7,14,21,and 28 d drought stress treatment.These physiological responses include osmotic regulating substance,antioxidant enzyme activity,malonaldehyde content,cell membrane permeability,and chlorophyll content.According to the results,the soluble protein content,proline concentration,malonaldehyde content,cell membrane permeability and CAT activity in Paspalum notatum’s leaf and root tended to increase with the prolongation of drought stress;the soluble sugar content and SOD activity first increased and then decreased;POD dropped gradually;the contents of chlorophyll a,b and total chlorophyll first declined,then mounted,and lastly dropped again.During the early stage of drought stress,SOD and CAT acted as the main antioxidant enzymes in Paspalum notatum’s leaf and root.However,with the aggravation of drought stress the predominant antioxidant enzymes became SOD in the root system whereas CAT and POD in the leaf.It implicates drought has a strong influence on root’s CAT and leaf’s SOD and POD.Leaf is the major organ regulating the osmosis and photosynthesis of Paspalum notatum.The findings can provide a useful theoretical basis for improving Paspalum notatum’s drought tolerance.展开更多
The somaclone, C39, derived by tissue culture from the obligate apomict Paspalum dilatatum cv Raki (2n=50), had 50 chromosomes and a karyotype apparently identical to Raki.SC2 seedlings of C39 showed a high degree of ...The somaclone, C39, derived by tissue culture from the obligate apomict Paspalum dilatatum cv Raki (2n=50), had 50 chromosomes and a karyotype apparently identical to Raki.SC2 seedlings of C39 showed a high degree of phenotypic variation which was of ten associated with increased chromosome numbers, but some of the variant seedlings were karyotypically indistinguishable from Raki or C39. Plants with increased chromosome numbers exhibited a high degree of intraplant chromosome variation (aneusomaty). In one of the SC2seedlings, the chromosome number of root tip cells varied from 58 to 82 and in several other seedlings the range was more than 10. The results suggested that the ability to form seed apomictically was much reduced in C39 and that this plant showed some capacity for sexual reproduction and the resulting seedlings, with a chromosome number of about 70, were genetically unstable. Of 11 SC2 seedlings examined cytolog ically, 6 did not produce any viable seed. Seedlings grown from seed of the remaining 5 plants showed that aneusomaty persisted in the SC3 generation. SC3 seedlings which were phenotypically similar to their maternal parent showed a similar range of chromosome numbers to that parent. Some of the SC3 seedlings exhibited an even wider range of chromosome numbers (e.g.56-136), and these plants were all dwarfs.展开更多
采用根箱法,结合Winrhizo2004a根系扫描测定系统,以豆科牧草柱花草和禾本科牧草黑籽雀稗为试验材料,研究不同施磷水平对柱花草和黑籽雀稗根系分布的影响。结果表明,2种牧草根系分布随土壤深度的增加而减少,柱花草集中分布于0～10 cm土层...采用根箱法,结合Winrhizo2004a根系扫描测定系统,以豆科牧草柱花草和禾本科牧草黑籽雀稗为试验材料,研究不同施磷水平对柱花草和黑籽雀稗根系分布的影响。结果表明,2种牧草根系分布随土壤深度的增加而减少,柱花草集中分布于0～10 cm土层,黑籽雀稗集中分布于0～20 cm土层;磷对2种牧草根系生长的影响存在较大的差异。低磷(P1,0.48 g P2O5/kg土)更适合柱花草根系和地上部分的生长,高磷(P3,1.92 g P2O5/kg土)水平对根系生长有抑制。黑籽雀稗对磷的需求量大,随着磷施入量的增加,根干重、总根长、根表面积、体积和根系平均直径均有所提高。展开更多
文摘The physiological responses of Paspalum vaginatum Sw. to Cd stress and its Cd accumulation characteristics were studied by investigating the effects of different concentrations of Cd on the growth, root vigor, leaf membrane permeability, membrane lipid peroxidation, protective enzyme activity and Cd accumulation of P. vaginatum. When the Cd concentration was over 50.00 mg/kg, with the increased Cd concentration, the CAT activity declined significantly, the synergistic effect between SOD and CAT was weakened, the MDA content increased greatly, and the root vigor decreased, leading to inhibited growth of P. vaginatum. When the Cd concentration was in the range of 0-50 mg/kg, the root vigor of P. vaginatum did not decline obviously, the activity of protective enzymes （SOD and CAT） was enhanced, and the MDA accumulation and cell membrane permeability did not increase significantly, thus the damage of Cd to P. vaginatum was lighter. Roots of P. vaginatum showed strong enrichment capacity for Cd. When the Cd concentration was up to 200.00 mg/kg, the Cd contents in shoot and root of P. vaginatum reached 39.15 and 1 097.38 mg/kg, respectively. It suggests that in the concentration range of 0-50.00 mg/kg, P. vaginatum can make effective responses to Cd stress and grow normally, and it can be planted as a candidate material to remediate Cd-contaminated soil.
基金Supported by National Key Research&Development Project(2016YFC0502603,2017YFD0502101-3)National Natural Science Foundation of China(31602005)+2 种基金Science and Technology Support Project of Guizhou Province(Qiankehe Support[2016]2516,Qiankehe Cheng Zhuan [2015]5324-2)Scientific and Technol-ogical Innovation Talents Team Construction Project(Qiankehe Platform Talents[2016]5617)Guizhou Province Outstanding Youth and Scientifictechnological Talents Cultivation Project(Qiankehe Ren[2015]02)~~
文摘To investigate the correlation and difference between Paspalum notatum’s leaf and root under drought adversity,this study tested the physiological responses of wild Paspalum notatum’s leaf and root under 0(CK),1,3,5,7,14,21,and 28 d drought stress treatment.These physiological responses include osmotic regulating substance,antioxidant enzyme activity,malonaldehyde content,cell membrane permeability,and chlorophyll content.According to the results,the soluble protein content,proline concentration,malonaldehyde content,cell membrane permeability and CAT activity in Paspalum notatum’s leaf and root tended to increase with the prolongation of drought stress;the soluble sugar content and SOD activity first increased and then decreased;POD dropped gradually;the contents of chlorophyll a,b and total chlorophyll first declined,then mounted,and lastly dropped again.During the early stage of drought stress,SOD and CAT acted as the main antioxidant enzymes in Paspalum notatum’s leaf and root.However,with the aggravation of drought stress the predominant antioxidant enzymes became SOD in the root system whereas CAT and POD in the leaf.It implicates drought has a strong influence on root’s CAT and leaf’s SOD and POD.Leaf is the major organ regulating the osmosis and photosynthesis of Paspalum notatum.The findings can provide a useful theoretical basis for improving Paspalum notatum’s drought tolerance.
文摘The somaclone, C39, derived by tissue culture from the obligate apomict Paspalum dilatatum cv Raki (2n=50), had 50 chromosomes and a karyotype apparently identical to Raki.SC2 seedlings of C39 showed a high degree of phenotypic variation which was of ten associated with increased chromosome numbers, but some of the variant seedlings were karyotypically indistinguishable from Raki or C39. Plants with increased chromosome numbers exhibited a high degree of intraplant chromosome variation (aneusomaty). In one of the SC2seedlings, the chromosome number of root tip cells varied from 58 to 82 and in several other seedlings the range was more than 10. The results suggested that the ability to form seed apomictically was much reduced in C39 and that this plant showed some capacity for sexual reproduction and the resulting seedlings, with a chromosome number of about 70, were genetically unstable. Of 11 SC2 seedlings examined cytolog ically, 6 did not produce any viable seed. Seedlings grown from seed of the remaining 5 plants showed that aneusomaty persisted in the SC3 generation. SC3 seedlings which were phenotypically similar to their maternal parent showed a similar range of chromosome numbers to that parent. Some of the SC3 seedlings exhibited an even wider range of chromosome numbers (e.g.56-136), and these plants were all dwarfs.
文摘采用根箱法,结合Winrhizo2004a根系扫描测定系统,以豆科牧草柱花草和禾本科牧草黑籽雀稗为试验材料,研究不同施磷水平对柱花草和黑籽雀稗根系分布的影响。结果表明,2种牧草根系分布随土壤深度的增加而减少,柱花草集中分布于0～10 cm土层,黑籽雀稗集中分布于0～20 cm土层;磷对2种牧草根系生长的影响存在较大的差异。低磷(P1,0.48 g P2O5/kg土)更适合柱花草根系和地上部分的生长,高磷(P3,1.92 g P2O5/kg土)水平对根系生长有抑制。黑籽雀稗对磷的需求量大,随着磷施入量的增加,根干重、总根长、根表面积、体积和根系平均直径均有所提高。
