鼠李糖脂-混合降解菌强化三角梅去除土壤中对硫磷

Interaction of rhamnolipids-mixed degrading bacteria to enhance removal of parathion from contaminated soils with Bougainvillea speetabilis

在温室盆栽条件下,通过单独或联合添加生物表面活性剂鼠李糖脂(RH)和接种混合降解菌(DB),研究了生物表面活性剂-微生物对三角梅修复对硫磷污染土壤的强化效果。结果表明,添加鼠李糖脂和接种混合降解菌可以促进三角梅的生长,特别是对植物根部促进作用显著(P<0.05),而种植三角梅使土壤中对硫磷的去除率提高了1.6倍。添加鼠李糖脂、接种混合降解菌可以促进三角梅对土壤中对硫磷的去除,50 d后去除率分别达到73.01%和77.13%,高于对照组(63.23%);两者的联合作用使土壤中对硫磷的去除率达到91.96%。三角梅从土壤中吸收的对硫磷主要积累于根部,对照组中三角梅地上部、根部对硫磷的积累量分别达到153.59、289.57μg·g^(-1),添加鼠李糖脂、接种混合降解菌显著降低了三角梅体内的对硫磷积累量(P<0.05)。同时发现,三角梅的存在显著提高了土壤脲酶、过氧化氢酶和碱性磷酸酶活性(P<0.05),添加鼠李糖脂和接种混合降解菌可以在不同程度上提高土壤中酶的活性。

Abstract：  Long term production and application of organophosphorus pesticide have resulted in serious soil contamination. A pot culture ex-periment under greenhouse conditions was carried out to investigate the interactive effect of rhamnolipids（RH）addition and mixed degrad-ing bacteria（DB）inoculation on the phytoremediation efficiency of Bougainvillea speetabilis for removal parathion from contaminated soils. Results indicated that rhamnolipids addition and mixed degrading bacteria inoculation could promote the growth of Bougainvillea speetabilis, especially for the underground part of plant. Bougainvillea speetabilis could promote the removal of parathion in soil by 1.6 times compared with the control. In plant treatment, the removal of parathion in soil was increased by rhamnolipids addition and mixed de-grading bacteria inoculation individually, 50 days later, the removal rate of parathion reached 73.01%and 77.13%, respectively, but only 63.23% for control. The combined effect of rhamnolipids addition and mixed degrading bacteria inoculation could promote the removal of parathion up to 91.96%. Parathion uptake by Bougainvillea speetabilis was mainly concentrated in the underground part, the parathion con-centration in aboveground part and underground part reached 153.59, 289.57μg·g-1 in the control treatment, respectively, rhamnolipids ad-dition and mixed degrading bacteria inoculation could reduce parathion accumulation in Bougainvillea speetabilis significantly（P〈0.05）. In addition, the presence of Bougainvillea speetabilis could promote soil urease activity, catalase activity and alkaline phosphatase activity sig-nificantly（P〈0.05）, rhamnolipids addition and mixed degrading bacteria inoculation could promote soil enzyme activity in different extent.