低浓度镉对柱花草土壤细菌的影响

摘要

通过盆栽试验，研究镉对柱花草土壤细菌类群的影响。结果表明：采用2．0和5．Omg／kgCd（N002．4H2O处理柱花草根系土壤．制成菌液．以不加镉的土壤菌液为对照，涂布计数得出2．0和5．0mg／kg的镉浓度属于抑制微生物生长的浓度。再从其中分离出20株菌株进行鉴定，其中1#和8#、2#和13#、9#和18#为同一菌种，鉴定结果1#、11#、16#为噬菌胞属（Cwophaga），2#、7#、20#为微球菌属（M／crococcus），3#、12#为芽孢杆菌属（Bacillus），掣为芽孢八叠球菌属（Svorosarcina）．5#为黄单胞菌属（Xanthomohas）．6#为色杆菌属（Chromobacterium）．9#为根瘤菌属∽hizobium），10#、14#为肠杆菌属（Enterobacter），15#为固氮菌属伪zotobacter），17#为德克斯氏菌属（Derxia），19。为沙雷氏菌属（Serratia）。%Pot experiment is conducted to study the effect of cadmium on bacteria of Stylosanthes rhizoshpere soil. Stylosanthes root system was treated with cadmium concentrations of 2.0 mg/kg and 5.0 mg/kg, contrasting with control group (with no cadmium), the bacteria liquid was made from root soil. Spreaded plate and counted bacterial numbers, the result showed cadmium with concentrations of 2.0 mg/kg and 5.0 mg/kg could inhibited growth of microbe. Twenty strains (1#-20#) of bacteria were isolated fxom the soil. 1# and 8#, 2# and 3#, 9# and 18# are the same. These strains of bacteria were identified. The strains 1#, 2#, 3#, 4#, 5#, 6#, 7#, 9#, 10#, 11#, 12#, 14#, 15#, 16#, 17#, 19#, 20# are named Cytophaga, Micrococcus, Bacillus, Sporosarcina, Xanthomonas, Chromobacterium, Micrococcus, Rhizobium, Enterobacter, Cytophaga, Bacillus, Enterobacter, Azotobacter, Cytophaga, Derxia, Serratia and Micrococcus.