接种嗜水气单胞菌对水稻降解毒死蜱的影响及作用机制  

Effect and mechanism of inoculation with Aeromonas hydrophila on the degradation of chlorpyrifos in rice

作　　者：张帆 马丽雅 冯发运 余向阳 唐文伟[1] 葛静[2] ZHANG Fan;MA Liya;FENG Fayun;YU Xiangyang;TANG Wenwei;GE Jing(College of Agriculture,Guangxi University,Nanning 530000,China;Jiangsu Key Laboratory of Food Quality and Safety,The Province and Ministry Jointly Build the National Key Laboratory Cultivation Base,Jiangsu Academy of Agricultural Sciences,Nanjing 210014,China)

机构地区：[1]广西大学农学院,南宁530000 [2]江苏省农业科学院、省部共建国家重点实验室培育基地、江苏省食品质量安全重点实验室,南京210014

出　　处：《农药学学报》2023年第2期422-434,共13页Chinese Journal of Pesticide Science

基　　金：国家重点研发计划课题(2021YFD1700803);国家自然科学基金(31872002).

摘　　要：从受毒死蜱污染的禾本科植物水稻Oryza sativa L.中分离出一株具有毒死蜱降解活性的内生细菌ST6,经16S rRNA鉴定为嗜水气单胞菌Aeromonas hydrophila。用绿色荧光蛋白基因(gfp)标记后得到标记菌株ST6-gfp,该菌株能成功定殖到水稻植株中,通过平板回收试验得出ST6-gfp在水稻根部数量为7.0~7.2 log CFU/g,在茎叶中数量为4.9~5.1 log CFU/g。通过室内盆栽试验探究了该内生细菌定殖水稻后对毒死蜱降解的影响,并初步解析了作用机制。结果表明,内生菌的定殖可显著降低水稻植株中的毒死蜱含量并促进植株生长,与未接菌植株相比,接菌植株中的毒死蜱含量降低了58.3%,株高、鲜重和叶绿素含量分别增加了38.9%、69.5%和41.5%。在毒死蜱胁迫下,ST6-gfp定殖增强了水稻氧化还原酶系和解毒酶系的活力,其中,超氧化物歧化酶(SOD)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)、谷胱甘肽还原酶(GR)、过氧化氢酶(CAT)和苯丙氨酸解氨酶(PAL)酶活性分别提升了1.1、1.3、1.2、1.8、1.22和1.7倍;细胞色素P450(CYP450)及谷胱甘肽-S-转移酶(GST)解毒酶活性上调了1.5~1.7倍;此外,接菌水稻丙二醛(MDA)的含量与未接菌的水稻相比降低了46.9%。研究结果表明,该菌株可良好地定殖在水稻体内,并可通过提高水稻抗氧化酶和解毒酶的活性加速水稻中毒死蜱的降解,进而减轻毒死蜱对水稻造成的胁迫损伤,提高对毒死蜱的耐受性。In this work,an endophytic bacterial strain ST6 with chlorpyrifos-degrading ability was isolated from chlorpyrifos-contaminated rice(Oryza sativa L.)and identified as Aeromonas hydrophila by 16S rRNA analysis.The strain ST6-gfp was successfully colonized in rice plants after being labeled with the green fluorescent protein gene(gfp),and the colony number of ST6-gfp in rice roots was 7.0-7.2 log CFU/g,and that in stems and leaves was 4.9-5.1 log CFU/g by plate recovery tests.The effect and the mechanisms of the endophytic bacteria colonization on the degradation of chlorpyrifos was investigated with pot experiments.The results show that the interaction between the plant and the endophytic bacteria promotes the degradation of chlorpyrifos and the growth of rice,and the content of chlorpyrifos in ST6-gfp inoculated rice is 58.3% lower than that in the uninoculated rice.The plant height,fresh weight and chlorophyll content of the inoculated rice increase by 38.9%,69.5%,and 41.5%,respectively,compared with the uninoculated control.Under chlorpyrifos stress,ST6-gfp colonization enhancs the activity of oxidoreductase and detoxification enzymes in rice,in which the activities of superoxide dismutase(SOD),peroxidase(POD),ascorbate peroxidase(APX),glutathione reductase(GR),catalase(CAT),and phenylalanine aminolase(PAL)enzymes increased by 1.1,1.3,1.2,1.8,1.2 and 1.7 fold,respectively;the activities of cytochrome P450(CYP450)and glutathione Stransferase(GST)were up-regulated by 1.5-1.7 fold.In addition,the MDA content of inoculated rice was reduced by 46.9% compared with that of uninoculated rice.This study suggests that ST6 colonization accelerates the degradation of chlorpyrifos in rice by increasing the activities of antioxidant and detoxification enzymes,thus reducing the stress damage caused by chlorpyrifos and improving the tolerance of rice to chlorpyrifos.

关 键 词：植物内生菌 嗜水气单胞菌 植物-内生菌相互作用 毒死蜱 生物降解 抗氧化酶系 水稻解毒酶系 

分 类 号：TQ450.1[化学工程—农药化工]