The toxic effects of heavy metal ions, Hg2＋, Pb2＋ and Cd2＋ on Colpoda inflata were studied, finding that the growth of C. inflata had been inhibited signifi- cantly under different concentrations of heavy metal ion...The toxic effects of heavy metal ions, Hg2＋, Pb2＋ and Cd2＋ on Colpoda inflata were studied, finding that the growth of C. inflata had been inhibited signifi- cantly under different concentrations of heavy metal ions. The acute toxicities of Cd2＋, Pb2＋ and Hg2＋ to C. inflata went in the order of Hg2＋, Pb2＋, Cd2＋. The results of joint toxicity showed that the types and magnitudes of joint actions were different at different solution compositions. The joint toxicity of Cd2＋ and Pb2＋ at the concentration proportion of 1：1 and toxic proportion of 1：1 were all antagonism. At the concentration proportion of 1：1, the joint toxicity of Pb2＋ and Hg2＋ was synergistic, and it changed from antagonism to synergistic at the toxic proportion of 1：1. The joint toxicily of Hg2. and Cd2＋ at the concentration proportion of 1：1 was synergistic, and it was antagonist at toxic proportion of 1：1. At the concentration proportion of 1：1：1, the joint toxicity of Cd2＋, Pb2. and Hg2＋ was synergistic, and it changed from antago- nism to synergistic under toxicity proportion of 1：1：1.展开更多
Little is known regarding the ability of protozoans to transfer phosphates and improve maize growth.The objective of this study was to determine whether Colpoda cucullus could improve the maize phosphorus(P) level by ...Little is known regarding the ability of protozoans to transfer phosphates and improve maize growth.The objective of this study was to determine whether Colpoda cucullus could improve the maize phosphorus(P) level by transferring phosphate.In this three-compartment root box study,the soil in the outer compartment was inoculated with the common ciliate,C.cucullus,together with the addition of either KH_(2)^(32)PO_(4),rock phosphate(RP),super phosphate(SP) or ammonium phosphate(AP),and then maize was grown in the inner compartment.The results showed that the maize plants grown in the soil inoculated with C.cucullus had much higher ^(32)P radioactivity than the control.Colpoda cucullus inoculation resulted in significant increases in dry matter by up to 25.07%,and nitrogen(N),P and potassium(K) absorption by 1–36%(P<0.05).Soil available P in the inner compartment of the root box was also enhanced by at least 30% due to the ciliate inoculation(P<0.05).It was therefore suggested that phosphates might be transported from the outer to inner compartments by the inoculated C.cucullus and then absorbed by the maize plant.展开更多
基金Supported by the Hubei Key Laboratory of Mine Environmental Pollution Control and Remediationthe Hubei Provincial Department of Education(B2013063)~~
文摘The toxic effects of heavy metal ions, Hg2＋, Pb2＋ and Cd2＋ on Colpoda inflata were studied, finding that the growth of C. inflata had been inhibited signifi- cantly under different concentrations of heavy metal ions. The acute toxicities of Cd2＋, Pb2＋ and Hg2＋ to C. inflata went in the order of Hg2＋, Pb2＋, Cd2＋. The results of joint toxicity showed that the types and magnitudes of joint actions were different at different solution compositions. The joint toxicity of Cd2＋ and Pb2＋ at the concentration proportion of 1：1 and toxic proportion of 1：1 were all antagonism. At the concentration proportion of 1：1, the joint toxicity of Pb2＋ and Hg2＋ was synergistic, and it changed from antagonism to synergistic at the toxic proportion of 1：1. The joint toxicily of Hg2. and Cd2＋ at the concentration proportion of 1：1 was synergistic, and it was antagonist at toxic proportion of 1：1. At the concentration proportion of 1：1：1, the joint toxicity of Cd2＋, Pb2. and Hg2＋ was synergistic, and it changed from antago- nism to synergistic under toxicity proportion of 1：1：1.
基金funded by the National Natural Science Foundation of China (41877059)。
文摘Little is known regarding the ability of protozoans to transfer phosphates and improve maize growth.The objective of this study was to determine whether Colpoda cucullus could improve the maize phosphorus(P) level by transferring phosphate.In this three-compartment root box study,the soil in the outer compartment was inoculated with the common ciliate,C.cucullus,together with the addition of either KH_(2)^(32)PO_(4),rock phosphate(RP),super phosphate(SP) or ammonium phosphate(AP),and then maize was grown in the inner compartment.The results showed that the maize plants grown in the soil inoculated with C.cucullus had much higher ^(32)P radioactivity than the control.Colpoda cucullus inoculation resulted in significant increases in dry matter by up to 25.07%,and nitrogen(N),P and potassium(K) absorption by 1–36%(P<0.05).Soil available P in the inner compartment of the root box was also enhanced by at least 30% due to the ciliate inoculation(P<0.05).It was therefore suggested that phosphates might be transported from the outer to inner compartments by the inoculated C.cucullus and then absorbed by the maize plant.
