O-phthalic acid is a kind of important pollutant, which accumulates in the environment with the extensive use of plastics and other products. Meanwhile, phthalic acid is one of the high content of allelopathic autotox...O-phthalic acid is a kind of important pollutant, which accumulates in the environment with the extensive use of plastics and other products. Meanwhile, phthalic acid is one of the high content of allelopathic autotoxic substances secreted by tobacco. The accumulation of phthalic acid in soil is an important cause of tobacco continuous cropping effect. In order to degrade phthalic acid accumulated in environment, the barrier effect of tobacco continuous cropping caused by phthalic acid accumulation in soil can be removed. A strain capable of degrading phthalic acid was isolated from sludge of sewage treatment plant and compared with 16 s DNA. The homology between this strain and Enterobacter sp. is 99%. The optimum growth conditions are as follows: pH7 at 30°C, 500 mg/L of o-phthalic acid, inoculation concentration ≥ 1.2% and its highest degradation rate of o-phthalic acid is 74%. The results of pot experiment showed that the degradation efficiency of o-phthalic acid in soil was about 40%, which alleviated the inhibitory effect of o-phthalic acid accumulation on tobacco growth.展开更多
文摘为探索长期连作状态下烟草根系分泌物内含有的化感物质组成成分,设置石英砂栽培和连作土壤栽培2种烟草培养处理,对2种烟草不同生长时期的根系分泌物进行提取,利用超高效液相色谱串联质谱(ultra-high performance liquid chromatography tandem mass spectrometry,UHPLC-MS/MS)对提取的根系分泌物进行分析,通过数据库比对、差异分析和时间聚类分析等方法筛选连作烟草根系分泌物中潜在的化感物质。结果表明,共筛选出11类潜在化感物质,分别为生物碱、萜类、胺类、有机酸、苯酸及其衍生物、脂肪酸、酚类、氨基酸和多肽、香豆素、肉桂酸及其衍生物和其他。生物碱、萜类、胺类和有机酸4类化合物相对含量占所有化合物的73.3%。L-烟碱、熊果酸、β-氨基丙腈、5-羟基吲哚乙酸、早熟素Ⅱ、单乙基己基邻苯二甲酸、己内酰胺、姜酚、L-乳酸、邻苯二甲酸二乙酯和2,3-二氢-3,5-二羟基-2-氧代-3-吲哚乙酸甲酯是连作烟草根系分泌物中相对含量较高的潜在化感物质。研究结果为烟草根系化感物质的化感作用研究及缓解烟草连作障碍方法研究提供理论基础。
文摘O-phthalic acid is a kind of important pollutant, which accumulates in the environment with the extensive use of plastics and other products. Meanwhile, phthalic acid is one of the high content of allelopathic autotoxic substances secreted by tobacco. The accumulation of phthalic acid in soil is an important cause of tobacco continuous cropping effect. In order to degrade phthalic acid accumulated in environment, the barrier effect of tobacco continuous cropping caused by phthalic acid accumulation in soil can be removed. A strain capable of degrading phthalic acid was isolated from sludge of sewage treatment plant and compared with 16 s DNA. The homology between this strain and Enterobacter sp. is 99%. The optimum growth conditions are as follows: pH7 at 30°C, 500 mg/L of o-phthalic acid, inoculation concentration ≥ 1.2% and its highest degradation rate of o-phthalic acid is 74%. The results of pot experiment showed that the degradation efficiency of o-phthalic acid in soil was about 40%, which alleviated the inhibitory effect of o-phthalic acid accumulation on tobacco growth.