Affiliation:
1. Fujian Engineering Research Center for Green Pest Management, Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Institute of Plant Protection Fujian Academy of Agricultural Sciences Fuzhou China
2. Fuzhou Scientific Observing and Experimental Station of Crop Pests of Ministry of Agriculture and Rural Affairs, Institute of Plant Protection Fujian Academy of Agricultural Sciences Fujian China
3. College of Plant Protection Fujian Agriculture and Forestry University Fuzhou People's Republic of China
Abstract
AbstractBACKGROUNDCitrus canker caused by Xanthomonas citri subsp. citri (Xcc) is a devastating bacterial disease that reduces citrus yield and quality, posing a serious threat to the citrus industry. Several conventional chemicals have been used to control citrus canker. However, this approach often leads to the excessive use of chemical agents, can exacerbate environmental pollution and promotes the development of resistant Xcc. Therefore, there is significant interest in the development of efficient and environmentally friendly technologies to control citrus canker.RESULTSIn this study, water‐soluble ZnO quantum dots (ZnO QDs) were synthesised as an efficient nanopesticide against Xcc. The results showed that the antibacterial activity of ZnO QDs irradiated with visible light [half‐maximal effective concentration (EC50) = 33.18 μg mL−1] was ~3.5 times higher than that of the dark‐treated group (EC50 = 114.80 μg mL−1). ZnO QDs induced the generation of reactive oxygen species (•OH, •O−2 and 1O2) under light irradiation, resulting in DNA damage, cytoplasmic destruction, and decreased catalase and superoxide dismutase activities. Transcription analysis showed downregulation of Xcc genes related to ‘biofilms, virulence, adhesion’ and ‘DNA transfer’ exposure to ZnO QDs. More importantly, ZnO QDs also promoted the growth of citrus.CONCLUSIONThis research provides new insights into the photocatalytic antibacterial mechanisms of ZnO QDs and supports the development of more efficient and safer ZnO QDs‐based nanopesticides to control citrus canker. © 2024 Society of Chemical Industry.