体外施用小分子RNA抑制稻瘟病菌分生孢子发育及致病性的作用效果  

The effect of in vitro application of small RNA on inhibiting conidia development and pathogenicity of Magnaporthe oryzae

作　　者：喻晗晞 丁绍晨 陈盼 圣聪 李绚 徐乐 赵弘巍[1] YU Hanxi;DING Shaochen;CHEN Pan;SHENG Cong;LI Xuan;XU Le;ZHAO Hongwei(College of Plant Protection/Laboratory of Bio-interactions and Crop Health,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]南京农业大学植物保护学院/生物互作与作物健康重点实验室,江苏南京210095

出　　处：《南京农业大学学报》2023年第2期257-265,共9页Journal of Nanjing Agricultural University

基　　金：江苏省农业科技自主创新项目[CX(21)3090];国家自然科学基金项目(31872040)。

摘　　要：[目的]本文旨在分析体外施加靶向细胞色素b(Cytb)的小分子RNA对稻瘟病菌致病性的抑制作用。[方法]将稻瘟病菌与双链小分子RNA(ds-sRNA MoCytb-21)共同孵育,通过测定孢子萌发效率和形态,确定小分子RNA对稻瘟病菌孢子萌发和附着胞形成有抑制作用。在分别施加溶剂(对照组)或dsRNA MoCytb-500(处理组)的情况下,使用稻瘟病菌菌株Guy11侵染水稻‘日本晴’,明确体外施加小分子RNA是否可以降低稻瘟病菌的致病能力。[结果]与对照相比,与小分子RNA共同孵育的稻瘟病菌孢子萌发率和附着胞形成率显著降低。2′-O-甲基修饰(OMe)和硫代甲氧基修饰(SOMe)能够延长小分子RNA的抑制效果。用Guy11和dsCytb混合喷施的水稻病斑面积较对照组显著降低。[结论]体外施加特异性靶向稻瘟病菌Cytb的小分子RNA能够抑制稻瘟病菌的致病性,具有开发成为高效绿色环保RNAi药剂的潜力和价值。[Objectives]The purpose of this study was to investigate the inhibitory effect of the in vitro applied small RNAs(sRNA)targeting cytochrome b(Cytb)on the pathogenicity of Magnaporthe oryzae,a causal agent of the rice blast disease.[Methods]The M.oryzae strain Guy11 was incubated with a double stand small RNA(ds-sRNA MoCytb-21)to assess the inhibitory effect of sRNA on conidial germination and appressorium formation.Both dsRNA MoCytb-500(treatment)or solution(control)were co-supplied with Guy11 conidia on rice‘Nipponbare’leaf surface,whereby the inhibitory effect of the in vitro applied sRNA on pathogenicity of Guy11 was examined.[Results]Compared with the control treatments,both conidial germination rates and appressorium formation rates of Guy11 incubated with sRNA were significantly reduced.Structural modifications such as 2′-methoxyl(OMe)and both phosphorothioate and 2′-methoxyl(SOMe)of sRNA could prolong the inhibitory effect.The lesion areas of leaves sprayed with both dsCytb and Guy11 conidia were significantly smaller than the control treatments.[Conclusions]The in vitro application of sRNAs specifically targeting Cytb of M.oryzae can inhibit the pathogenicity of M.oryzae,which has the potential and value to be developed into an efficient and green RNAi fungicide.

关 键 词：细胞色素B 稻瘟病 抗病性 喷雾诱导基因沉默 RNAi药剂 

分 类 号：S432.44[农业科学—植物病理学]