纳米氧化锌对烟草疫霉菌的抑菌作用研究

Study on the Antifungal Effect of Zinc Oxide Nanoparticles on Phytophthora nicotianae

烟草黑胫病是由烟草疫霉菌(Phytophthora nicotianae)引起的一种毁灭性真菌病害,发病率高,分布范围广,严重威胁烟草业的可持续发展.目前,抗病育种和化学防治是防治该病害的主要措施,但这些方法存在很多弊端.因此,寻求新策略高效防治黑胫病已经迫在眉睫.本研究在室内条件下研究纳米氧化锌(ZnO NPs)对烟草疫霉菌的抗真菌活性.结果发现,ZnO NPs显著抑制烟草疫霉菌菌丝生长,降低孢子囊产生,降低游动孢子萌发率,且呈现浓度依赖性,尤其是当处理浓度达到800 mg/L时,菌丝几乎不再生长,游动孢子完全不萌发.通过透射和扫描电镜观察发现,ZnO NPs破坏疫霉菌菌丝结构,导致菌丝干瘪、形态畸形、细胞质空化.本研究为发展ZnO NPs做为潜在农业抗真菌剂提供了理论基础.

Tobacco black shank disease,caused by Phytophthora nicotianae,is a devastating disease,which puts a serious threat to the sustainable development of the tobacco industry.At present,the main control measures of tobacco black shank disease are still application of chemical agents and cultivation of resistant varieties.However,these control technologies have many disadvantages.Therefore,it is urgent to seek new strategies to effectively prevent black shank disease.In order to provide a theoretical basis for the development of potential agricultural antifungal agents,the antifungal activity of zinc oxide nanoparticles(ZnO NPs)against P.nicotianae in vitro was investigated in laboratory.The results showed that ZnO NPs significantly inhibited mycelial growth of Ph.nicotianae,decreased its sporangium production,and reduced its zoospore germination rate,all of which appeared to be concentration-dependent.Especially,when the concentration of ZnO NPs reached 800 mg/L,the mycelia barely stopped growing and the zoospore hardly germinated.Transmission electron microscopy(TEM)and scanning electron microscopy(SEM)examinations revealed that ZnO NPs destroyed the mycelial structure of P.nicotianae,resulting in mycelial shrinkage,morphological deformities and cytoplasmic cavitation.