纳米氢氧化铜对茶炭疽病菌的抑制活性及作用机制  

Antimicrobial activity and mechanism of nano-Cu(OH)_(2) against tea anthracnose pathogen

作　　者：石文波 黄楚平 陈宇航 郭雪萍 徐佳微 关雄 潘晓鸿 SHI Wenbo;HUANG Chuping;CHEN Yuhang;GUO Xueping;XU Jiawei;GUAN Xiong;PAN Xiaohong(College of Plant Protection,Fujian Agriculture and Forestry University,State Key Laboratory of Ecological Prevention and Control of Crop Pests in Fujian and Taiwan&Key Laboratory of Biopesticide and Chemical Biology,Ministry of Education,Fuzhou 350002,China)

机构地区：[1]福建农林大学植物保护学院,闽台作物有害生物生态防控国家重点实验室,生物农药与化学生物学教育部重点实验室,福州350002

出　　处：《农药学学报》2024年第5期962-973,共12页Chinese Journal of Pesticide Science

基　　金：国家重点研发计划(2022YFD1400700);福建农林大学茶树绿色栽培与生态茶园建设研究(K1520005A03);福建农林大学科技发展资金(KFB23012)。

摘　　要：本研究采用组织分离法从茶叶患炭疽病处获得了病原菌并进行了鉴定,通过沉淀法合成了纳米Cu(OH)_(2)并对其进行了表征,探究了纳米Cu(OH)_(2)对茶炭疽病原菌的抑制活性及抑菌机理。结果表明:从茶叶上分离所得病原菌与暹罗炭疽菌(Colletotrichum siamense)为同一分支,自检支持率高达91%,确定所分离的病原菌为暹罗炭疽菌。所合成的纳米Cu(OH)_(2)呈花簇状、束状以及聚集状,平均粒径为26.5 nm,且存在一定的团聚现象。300 mg/L的纳米Cu(OH)_(2)处理后2 d对暹罗炭疽菌的抑制率最高可达99.16%。C.siamense的Zeta电位为(-8.91±1.80)mV,而纳米Cu(OH)_(2)的电位为(12.55±1.33)mV,两者通过静电作用使得纳米Cu(OH)_(2)具有较强的抑菌效果。经纳米Cu(OH)_(2)处理后,病原菌的菌丝出现明显的凸出和畸变,损坏严重,且细胞膜破裂,同时产生了大量活性氧,大部分细胞死亡。DNA损伤测定结果显示,纳米Cu(OH)_(2)致使茶炭疽病菌DNA条带更窄且更暗,随着纳米Cu(OH)_(2)浓度的提高,所提取出来的DNA浓度变低。抗氧化酶活性及丙二醛(MDA)含量测定结果表明,菌体中超氧化物歧化酶(SOD)含量降低,MDA含量增加。综上,纳米Cu(OH)_(2)通过诱导病原菌细胞膜的破坏、DNA损伤、抑制SOD活性及促进MDA产生致使细胞死亡。本研究可为纳米农药防治茶炭疽病提供新的思路。In this study,the pathogen was obtained from the tea leaves suffering from tea anthracnose by tissue isolation method and identified.Moreover,nano-Cu(OH)_(2) was prepared by the precipitation method and characterized and the inhibitory activity and inhibition mechanism of nano-Cu(OH)_(2) on the tea anthracnose pathogen were investigated.The results show that the pathogen isolated from tea leaves clustered with Colletotrichum siamense on the same branch with a self-support rate as high as 91%,confirming the isolated pathogen was C.siamense.The morphology of synthesized nano-Cu(OH)_(2) were petal-like,bunchy,and clustered nanoparticles,accompanied by an aggregation phenomenon.The highest inhibition rate of 99.16%to C.siamense was achieved at 2 days of treatment 300 mg/L nano-Cu(OH)_(2) treatment.The Zeta potential of C.siamense was(−8.91±1.80)mV and that of nano-Cu(OH)_(2) was(12.55±1.33)mV.The strong antimicrobial effect of nano-Cu(OH)_(2) might be due to electrostatic interactions.After treatment with nano-Cu(OH)_(2),the fungal hyphae showed obvious protrusions and distortions,severe damage,and ruptured fungal cell membranes.Concurrently,a significant amount of reactive oxygen species was generated,resulting in the death of most cells.DNA damage measurements showed that nano-Cu(OH)_(2) treatment caused the tea anthracnose pathogen DNA bands narrower and darker,and as the concentration of nano-Cu(OH)_(2) increased,the DNA concentration decreased.The results of antioxidant enzyme activity and malondialdehyde(MDA)content measurements showed a decrease in superoxide dismutase(SOD)activity and an increase in MDA content in the fungi.In conclusion,these results suggest that nano-Cu(OH)_(2) can induce pathogenic cell membrane damage,DNA damage,inhibition of SOD activity,and promotion of MDA production,ultimately leading to cell death.These findings would provide a new approach for the effective control of tea anthracnose using nano-pesticides.

关 键 词：纳米Cu(OH)_(2) 茶炭疽病 病原菌鉴定 暹罗炭疽菌抑菌活性 抑菌机理 

分 类 号：S432[农业科学—植物病理学]