To investigate the mechanism by which ZnO NPs affect the growth of B. cinerea and P. expansum, SEM analysis was employed to examine the structural changes of fungal samples after ZnO NP treatment. PDA media containing 12 mmol l−1 ZnO NPs were prepared, and fungal samples were then inoculated onto the PDA plate and incubated at 25 ◦ C for 12 days.