Abstract This study was undertaken to determine the effect of aromatic hydrocarbons on growth and plant growth promoting activities of Azotobacter chroococcum strain JL104. The organism was grown on Jensen’s media without sucrose, supplemented with different concentrations of aromatic hydrocarbons. Azotobacter chroococcum strain JL104 was able to grow in the presence of benzene, toluene, aniline and benzoic acid and was able to utilize these as sole carbon source as well. The culture showed the highest growth in presence of 0.5% concentrations of aniline and benzoic acid and 0.01% concentrations of benzene and toluene. Maximum indole acetic acid (IAA) production and acetylene reduction activity (ARA) were recorded with benzene and benzoic acid, respectively. Among other substituted benzene derivatives such as xylene, p-hydroxybenzoic acid, di-nitrophenol and di-chlorophenol, xylene was observed to be the least toxic and di-nitrophenol the most toxic hydrocarbon. The highest soil survival was found in soil amended with 1% sucrose however, the population of A. chroococccum strain JL104 declined continuously in unamended soil. Amongst various hydrocarbons, 0.1% toluene amended soil supported the maximum survival, indicating it to be least toxic aromatic hydrocarbon carbon in soil.

中文翻译：

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芳香烃对色球固氮菌JL104株生长、植物促生活性及土壤中存活率的影响

摘要 本研究旨在确定芳香烃对色球菌固氮菌JL104 生长和植物促生长活性的影响。该生物体在不含蔗糖、补充有不同浓度芳烃的 Jensen 培养基上生长。Azotobacter chroococcum 菌株 JL104 能够在苯、甲苯、苯胺和苯甲酸的存在下生长，并且能够利用这些作为唯一的碳源。在 0.5% 浓度的苯胺和苯甲酸以及 0.01% 浓度的苯和甲苯存在下，培养物显示出最高的生长。分别用苯和苯甲酸记录了最大吲哚乙酸 (IAA) 产量和乙炔还原活性 (ARA)。在其他取代苯衍生物中，如二甲苯、对羟基苯甲酸、二硝基苯酚和二氯苯酚，观察到二甲苯毒性最小，二硝基苯酚毒性最大。在用 1% 蔗糖改良的土壤中发现了最高的土壤存活率，然而，在未改良的土壤中，A. chroococccum JL104 菌株的数量持续下降。在各种碳氢化合物中，0.1% 甲苯修饰的土壤支持最大的存活率，表明它是土壤中毒性最小的芳香烃碳。