高产铁载体菌Burkholderia vietnamiensis YQ9促生特性研究及其对重金属胁迫条件下种子萌发的影响  

Studies on growth-promoting properties of an efficient siderophore producing bacterium,Burkholderia vietnamiensis YQ9,and its effects on seed germination under heavy metal stress

作　　者：王亚军 冯炬威 李雅倩 虞方伯[1] WANG Yajun;FENG Juwei;LI Yaqian;YU Fangbo(Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province,Zhejiang Agricultural and Forestry University,Hangzhou 311300;Zhejiang Huanxin Environmental Automatic Detection Co.,Ltd.,Hangzhou 311300)

机构地区：[1]浙江农林大学,浙江省土壤污染生物修复重点实验室,杭州311300 [2]浙江环信环境自动检测有限公司,杭州311300

出　　处：《环境科学学报》2022年第2期430-437,共8页Acta Scientiae Circumstantiae

基　　金：浙江省重点创新团队资助项目(No.2013TD12)。

摘　　要：本研究以Burkholderia vietnamiensis YQ9为供试菌株,明确其产铁载体能力,研究其产吲哚乙酸(Indole acetic acid,IAA)、溶磷解钾和1-氨基环丙烷-1-羧酸(1-Aminocyclopropane-1-carboxylate,ACC)脱氨酶活性等促生特性.发现B.vietnamiensis YQ9铁载体活性单位(Siderophore unit,SU)高达96.6%,兼具分泌IAA、溶磷,以及产ACC脱氨酶能力.YQ9的IAA产量为6.93 mg·L^(-1);在含有磷酸三钙的培养基中培养后,其上清液中的可溶性磷含量为104.06 mg·L^(-1);ACC脱氨酶活性为8.71μmol·h^(-1)·mg^(-1).此外,在含不溶性重金属的培养基中接种YQ9,上清液中Cu^(2+)、Zn^(2+)和Cd^(2+)含量显著提升,与对照相比分别增加了69.89%、83.80%和51.59%.通过研究重金属胁迫下不同处理对黑麦草和甜高粱种子萌发的影响,发现YQ9及其培养上清液对供试种子的发芽率有明显提升作用.上述结果表明,菌株YQ9具备优异的促生特性,能提高不溶性重金属的溶解性,例如Cu^(2+)、Zn^(2+)和Cd^(2+),促进重金属胁迫下植物种子的发芽率,结果有助于丰富铁载体和微生物-植物联合修复重金属污染土壤的科学研究与应用实践,并可为缓解能源作物与粮食作物的用地之争提供借鉴.In this study,Burkholderia vietnamiensis YQ9 was selected as the test strain to investigate siderophore production capacity and growthpromoting properties such as indole acetic acid(IAA)production,phosphorus and potassium solubilities,and deaminase activity of 1-aminocyclopropane-1-carboxylate(ACC).It was found that the siderophore unit(SU)of B.vietnamiensis YQ9 was up to 96.6%.The strain owns the ability to produce IAA,dissolve phosphorus,and produce ACC deaminase.The production of IAA was 6.93 mg·L^(-1).While B.vietnamiensis YQ9 was incubated in the medium containing tricalcium phosphate,the content of soluble phosphorus in supernatant was 104.06 mg·L^(-1).The ACC deaminase activity was 8.71μmol·h^(-1)·mg^(-1).While media containing insoluble heavy metals were inoculated with the test strain,the contents of Cu^(2+),Zn^(2+) and Cd^(2+) in the supernatant were significantly increased by 69.89%,83.80%and 51.59%,respectively.The effects of B.vietnamiensis YQ9 on seed germination of Lolium perenne and sweet sorghum(Sorghum bicolor(L.)Moench)under heavy metal stress were also studied.It was found that B.vietnamiensis YQ9 and its culture supernatant could significantly improve seed germination rates.Accordingly,the strain has excellent growthpromoting properties,could enhance the solubilities of insoluble heavy metals such as Cu^(2+)、Zn^(2+) and Cd^(2+),and improve the germination rates of test seeds under heavy metal stresses.This work is helpful to enrich the scientific research and application of siderophore and microbial-plant combined remediation of heavy metal contaminated soil,and could provide reference for alleviating land-using conflict between energy and food crops.

关 键 词：铁载体 促生特性 黑麦草 甜高粱 种子萌发 

分 类 号：X172[环境科学与工程—环境科学]