纳米氢氧化镁对茶叶黑斑病原真菌活性的抑制效应研究  

Study on the Inhibition Effect of Nano-Mg （OH）2 to Tea Blackspot Disease Pathogenic Fungi Activity

作　　者：陈蓉[1] 邱赛飞 游雨欣 谢勇啸 聂丹玥 李嘉欣 王财成 关雄[1] 潘晓鸿[1] CHEN Rong;QIU Sai-Fei;YOU Yu-Xin;XIE Yong-Xiao;NIE Dan-Yue;LI Jia-Xin;WANG Cai-Cheng;GUAN Xiong;PAN Xiao-Hong(State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops / Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education / College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China;College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China)

机构地区：[1]福建农林大学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/植物保护学院,福州350002 [2]福建农林大学资源与环境学院,福州350002

出　　处：《农业生物技术学报》2019年第8期1460-1466,共7页Journal of Agricultural Biotechnology

基　　金：国家重点研发计划(No.2017YFD0200400);国家自然科学基金青年项目(No.31601686);福建农林大学校杰出青年项目(No.xjq201719)

摘　　要：茶叶真菌病害是引起茶叶减产的重要原因之一,纳米材料作为环境友好型抗菌材料可应用于抑制茶叶真菌病害。本研究通过共沉淀法合成纳米氢氧化镁(nano-Mg(OH)2),研究其抑制茶叶黑斑病原真菌的效果。采用X-射线粉末衍(X-ray powder diffraction, XRD)表征nano-Mg(OH)2的尺寸,通过谢乐公式计算得出合成的纳米颗粒在(101)面的尺寸为14.5 nm。利用扫描电镜(scanning electron microscope,SEM)对nano-Mg(OH)2的形貌进行观察,发现纳米颗粒结构呈规则的片状。对茶叶黑斑病原真菌进行分离纯化,通过形态学观测、核糖体DNA内转录间区(internal transcribed spacer, ITS)序列分析、ITS区特异性引物PCR检测和系统发育关系比较,确定分离的病原菌为芒果球座菌(Guignardia mangiferae),茶叶上此类真菌的报道较少。采用平板涂布的方法,以空白对照和阳性对照(碱性条件)为对照组,以不同浓度nano-Mg(OH)2为实验组,经培养一段时间后通过十字交叉法测量真菌生长直径并计算抑制率。结果表明,nano-Mg(OH)2能有效的抑制茶叶真菌的生长,5 mg/mL nano-Mg(OH)2在3 d时对菌丝生长抑制率可达48.78%,随着浓度增加效果更为显著,50 mg/mL nano-Mg(OH)2对菌丝生长有100%的抑制率,半最大效应浓度(half maximal effective concentration, EC50)为7.63 mg/mL。研究结果可为后续研发安全、有效的纳米制剂提供科学依据和技术支持。Fungal diseases of tea are one of the important causes of tea yield reduction. As environmentally friendly antimicrobial materials, nano-materials can be used to inhibit tea fungal diseases. In this study, nanoMg(OH)2 was synthesized by coprecipitation method, and the inhibitory effect on tea blackspot pathogenic fungi of tea by nano-Mg(OH)2 was studied. The synthesized nano-Mg(OH)2 was characterized by X-ray powder diffraction(XRD), and the size of nano-Mg(OH)2 at(101) direction was 14.5 nm according to the Scherrer equation. Scanning electron microscopy(SEM) was applied to observe the morphology of nano-Mg(OH)2, and it was found that the nanoparticles were regular sheets of structure. Based on the morphological characteristics, internal transcribed spacer(ITS) sequence analysis of ribosomal DNA, ITS-specific primers PCR detection and phylogenetic comparison, it was confirmed that the isolated pathogen was Guignardia mangiferae, which was rarely reported in tea. The water and alkaline condition were set as blank and positive control groups, nano-Mg(OH)2 with different concentrations were used as experimental groups. After plate coating, the growth diameter of fungi was measured by cross-over method and the inhibition rate was calculated after a period of culture. The results showed that nano-Mg(OH)2 could effectively inhibit the growth of tea fungi, the inhibition rate of 5 mg/mL nano-Mg(OH)2 on mycelial growth was 48.78% in 3 days, and the inhibition rate of 50 mg/mL nano-Mg(OH)2 was 100%, which implying that the inhibition rate was increased with the concentration, and the half maximal effective concentration(EC50) of nano-Mg(OH)2 was 7.63 mg/mL. This study provides scientific basis and technical support for the subsequent research and development of safe and effective nano-preparations.

关 键 词：纳米氢氧化镁 茶叶黑斑病 抑制真菌 

分 类 号：S432[农业科学—植物病理学]