Graphene Oxide-Based Antifungal Pesticide Delivery System for Tobacco Fungal Disease (Tobacco Target Spot) Control

In recent years, nanocarrier-based pesticide delivery systems have provided new possibilities for the efficient utilization of pesticides. In this research, we developed a hydroxypropyl-β-cyclodextrin-modified graphene oxide (GO-HP-β-CD) nanocarrier for pyraclostrobin (Pyr) delivery and studied its application for tobacco target spot disease control. GO-HP-β-CD has excellent pesticide-loading performance for Pyr (adsorption capacity of 1562.5 mg/g) and good water dispersibility and stability. Besides, GO-HP-β-CD shows pH-responsive release performance. In addition, GO-HP-β-CD also has better leaf affinity than Pyr, and it can effectively adhere to the leaf surface after simulated washing. The results of antifungal experiments indicate that GO-HP-β-CD-Pyr has a good preventive effect on tobacco target spot disease, and its EC50 value is 0.384 mg/L, which is lower than Pyr. Specifically, this nanopesticide formulation does not contain toxic organic solvent or additive, so it has good environmental friendliness. Therefore, we believe that the GO-HP-β-CD-Pyr nanopesticide has brilliant potential in the prevention and control of tobacco diseases.