接种邻苯二甲酸酯(PAEs)降解菌缓解PAEs对玉米胁迫效应和机制研究  

Alleviation of Phthalic Acid Ester(PAE) Stress on Maize by Inoculating PAEs-degrading Strain

作　　者：陈学斌[1] 赵海明[1] 莫测辉[1] 蔡全英[1] CHEN Xuebin;ZHAO Haiming;MO Cehui;CAI Quanying(School of Environment, Jinan University, Guangzhou 510632, China)

机构地区：[1]暨南大学环境学院,广东广州510632

出　　处：《生态环境学报》2017年第3期493-499,共7页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(41573087;U1501233);广东省自然科学基金研究团队项目(1614060000034);广东省应用型科技研发专项项目(2016B020242005)

摘　　要：邻苯二甲酸酯(PAEs)是一类典型的环境内分泌干扰物,国内农业土壤普遍受PAEs的污染。土壤中的PAEs可被农作物吸收累积,影响植物的生理生化特性和农产品的质量安全。探索PAEs污染土壤的生物修复技术以及高效降解菌缓解PAEs污染胁迫和降低农作物吸收累积PAEs迫在眉睫。以在土壤中的质量分数和检出频率均较高的邻苯二甲酸二(2-乙基己基)酯(DEHP)为目标化合物,采用DEHP污染土壤(18 mg·kg^(-1)和75 mg·kg^(-1))进行盆栽玉米(Zea mays)试验,研究接种PAEs高效降解菌(嗜吡啶红球菌Rhodococcus pyridinivorans XB)缓解DEHP胁迫对玉米生长、吸收积累DEHP的影响及其抗氧化酶系统的响应。结果显示,经DEHP处理的玉米丙二醛质量摩尔浓度显著增加(P<0.05),尤其是高浓度处理的玉米根系丙二醛质量摩尔浓度增加464%;且高浓度处理的玉米根系过氧化氢酶和多酚氧化酶活性显著增加(P<0.05),生物量显著下降(P<0.05),说明DEHP严重影响玉米的生长。与不接种微生物处理相比,玉米接种菌株XB能显著提高玉米体内超氧化物歧化酶(10%~154%)、过氧化氢酶(11%~34%)及多酚氧化酶(48%~288%)活性,显著降低丙二醛质量摩尔浓度(30%~60%),提高玉米生物量(5%~85%),减少玉米对DEHP的吸收积累(4%~60%)。结果说明菌株XB能缓解土壤DEHP对玉米生长的胁迫,降低玉米吸收积累DEHP,有利于保障农产品质量安全。Phthalic acid esters(PAEs)is a class of typical enviromnental endocrine disrupters.In China,the agricultural soil was generally contaminated by PAEs.PAEs in soil can affect plant growth and their physiological and biochemical characteristics,and also can be taken up and accumulated by crop which affects the safety of agricultural products.It is very urgent to explore the bioremediation technologies of PAEs contaminated soil and to investigate the alleviation of efficient PAE-degrading strain on PAE stress and reduction of PAE uptake and accumulation by crops.In this study,di(2-ethylhexyl)phthalate(DEHP),with higher detection frequency and concentrations among PAE compounds in soil,was selected as the target compound.Maize(Zea mays)was grown in DEHP contaminated soil with concentrations of18and75mg-kg"1(namely low and high DEHP treatment,respectively)by the pot experiment,and efficient PAE-degrading bacterium(Rhodococcus pyridini^vorans XB)was inoculated in maize to investigate its alleviation of DEHP stress on maize growth and DEHP accumulation.Results show that soil DEHP significantly increased malondialdehvde(MDA)content of maize(P<0.05),especially for the root of high DEHP treatment(by464%).Correspondingly,the maize biomass of the high DEHP treatment decreased significantly(P<0.05),even though the activities of superoxide dismutase and catalase of maize root significantly increased(P<0.05),indicating serious DEHP stress occurred on maize.Compared with non-inoculated microbe treatment,inoculating strain XB could significantly improve the activities of superoxide dismutase(by10%~154%),catalase(by11%~34%),polyphenol oxidase(by48%~288%)and increase maize biomass(by5%~85%),while reduced malondialdehvde content(by30%~60%)and DEHP accumulation of maize(by4%~60%).This suggests that the strain XB could alleviate the stress of DEHP on maize growth,reduce accumulation of DEHP in maize,which is helpful for ensuring the safety of agricultural products.

关 键 词：邻苯二甲酸二(2-乙基己基)酯 嗜吡啶红球菌 玉米 抗氧化酶系统 吸收累积 

分 类 号：X172[环境科学与工程—环境科学]