【作者】 廖金英；

【导师】 赵士熙；

【作者基本信息】 福建农林大学 ， 农业昆虫与害虫防治， 2004， 硕士

【摘要】 从土壤中分离筛选获得两株对甲胺磷农药有较强降解效能的甲胺磷降解细菌，经鉴定分别为头状葡萄球菌（Staphylococcus capitis）（称为D菌）和粪产碱菌（Alcaligenes faecalis）（称为J菌）。 采用气相色谱法测定甲胺磷农药的残留，甲胺磷在水中的添加回收率在92.896至96.4％之间，变异系数在2.2％至3.9％之间，甲胺磷的标准曲线为Y=398421+2530507X，r=0.9917。甲胺磷降解细菌的活菌数和用分光光度计测定的其菌体悬浮液的浓度的OD_650mm呈现显著直线关系，回归方程为y=0.1233x-2.3051，r=0.9171。 降解细菌D菌和J菌都能降解甲胺磷，D菌和J菌在甲胺磷浓度为500mg／L，30℃，180r／min摇床上用基础培养基培养72小时，对甲胺磷的降解率分别达到58.49％和65.80％。D菌和J菌具有联合作用，两菌混合培养可提高对甲胺磷的降解效能，72小时中对甲胺磷的降解率达到72.93％。甲胺磷降解细菌D菌和J菌在甲胺磷浓度不同的情况下的生长存在显著差异，30℃，180r／min摇床上用基础培养基培养72小时，D菌在1000mg/L的甲胺磷浓度下生长最好，J菌在2000 mg／L的甲胺磷浓度下生长最好。 甲胺磷降解细菌的生长曲线测定表明，30℃，180r／min摇床上用改造的基础培养基培养，D菌在培养6小时后进入对数生长期，18小时后进入稳定生长期，36小时后进入衰败期。J菌在培养18小时后才进入对数生长期，30小时后进入稳定生长期，39小时后开始衰败期。 甲胺磷降解细菌D菌和J菌在土壤中的施用，有利于提高整体土壤微生物的活性。培养基的pH值对甲胺磷农药的降解细菌的生长有较大的影响。不同pH值的缓冲液配制的培养基相对于直接用蒸馏水配制的更有利于降解菌的生长。D菌和J菌都在缓冲液pH值为6时生长最好，30℃，180r／min摇床上用基础培养基培养，培养72小时后的OD_650mm值分别为1.093和1.586，而用蒸馏水配制的不同pH值的培养基，D菌和J菌的最适生长pH值都为7，培养72小时后的OD_650mm值分别为0.756和0.858，并且培养后的培养基的DH也出现了较大的变化。 甲胺磷降解细菌D苗和J菌经紫外诱变后。筛选出D菌的突变株D1和J菌的突变株福建农林大学硕士学位论文甲胺磷降解细菌的分离、鉴定和降解特性研究J3，30℃培养3d后对甲胺磷的降解率达到52.85%和56.6既，分别比出发菌株提高了5.87%和5.70%。农药斜面连续传代10次，降解活力保持穆定。突变株和出发菌株在农药降解谱上没有明显差异。 添加一定的碳源有利于降解菌的生长。在培养基中加入1%的葡萄糖量对出发菌株D菌和J菌及突变菌株D1菌和J3菌的生长都达到最理想的促进作用。 分别用甲胺磷降解菌和培养液灌施，芥菜苗上的桃蚜死亡率没有显著差异。在灌施IO00mg/L甲胺磷溶液的同时也施入甲胺磷降解细菌，桃蚜的死亡率比只灌施甲胺磷的有极显著的降低，而在灌施甲胺磷之前24小时就加有甲胺磷降解细菌的，其上生长的桃蚜的死亡率比施药同时加菌的和只灌施甲胺磷的都有大幅度的降低。更多还原

【Abstract】 Two degrading methamidophos bacteria strains were isolated from the soil, they were identified as Staphylococcus capitis and Alcaligenes faecalis., and named as strain D and strain J.Methamidophos residues in soil were determined by gas chromatography. The average recovery rates in water were between 92.8% and 96.4%, and variation coefficients were between 2.2% and 3.9%. The standard curve of formulum was Y=398421+ 2530507X (r=0.9917). The number of living Methamidophos-degrading bacterium was positively coordinated with the OD650mm of its suspension liquid determined by spectrophotometer.the regression equation was y=0.1233x-2.3051 (r=0.9171).Methamidophos-degrading bacteria strain D and strain J were able to utilize methamidophos as the carbon and energy source for growth. Strain D and strain J were cultivating 72 hours in basic culture medium with 500mg/L methamidophos and shaking (180r/min) at 30℃, methamidophos was degraded 58.49% and 65.80% respectively. When strain D combined with strain J, the degradation rate was higher than that of either of strain administered singularly.After 72 hours ,72.93% was degraded. For strain D the optimal methamidophos concentration was 1000 mg/L, but that for strain J was 2000 mg/L.The growth curve results indicated, in basic culture medium with 500mg/L methamidophos and shaking (180r/min) at 30℃, strain D entered grow logarithm long-termly after being cultivated 6 hours, entered grow steadily long-termly 18 hours later, and began to decline 36 hours later.The periods for strain J were 18 hours,30 hours,and 39 hours respectively.Strain D and strain J used in the soil helped to improve the activity of the whole soil microorganism group. There was relatively great influence on the growth of the methamidophos degradating bacterium in pH value of the culture medium. Buffering liquid helped the growth of degrading bacteria even more the culture medium compounded with thedistilled water that the liquid compounded of different pH value. Strain D and Strain J are all growed best while buffering liquid pH value for 6. trained with the basic culture medium and shaking(180r/min) at 30C, the OD650mm value 72 hours later were 1.093 and 1.586 respectively, and the culture medium of different pH value compounded with the distilled water , Strain D and Strain J most right to grow pH value 7 , the OD650mm after 72 hours were 0.756 and 0.858 respectively, and pH value of the culture medium has presented greater change.The mutant strain D1 and strain J3 obtained from strain D and strain J respectively mutated through ultraviolet ray. trained on basic culture medium at 30C, the strain Dl and strain J3 could degrade methamidophos by 52.85% and 56.66% in 3 days respectively, were 5.87% and 5.70% higher. The mutants were generated 10 times on the tube medium containing methamidophos and showed the degradative capacity were stable. After mutation the degradation spectrum did not chang for the both mutants.Add extra carbons source helped to the growth of degrading bacteria.One percent glucose had the higher effect.The bacteria or their cultivation media had no effect on peach aphids survival.But treat mustard root area with 1000 mg/L methamidophos and bacteria suspension liquid spontaneously or alternatively could reduce their mortality rate, and pretreating with bacteria suspension liquid 24 hours earlier affected most更多还原