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
Key words
nano-Cu(OH)2/tea anthracnose/identification of pathogenic fungi/antibacterial activity of Colletotrichum siamense/antibacterial mechanism
维普
万方数据