Inhibitory effect of chlorine dioxide (ClO2) fumigation on growth and patulin production and its mechanism in Penicillum expansum

The effect of chlorine dioxide (ClO2) on Penicillium expansum growth and patulin production in vitro and on its disease severity in apples was investigated. ClO2 treatment significantly reduced the lesion diameter in apples infected with P. expansum and inhibited mycelial growth and spore germination. After ClO2 treatment, P. expansum mycelial morphology was strongly affected, and a reduced spore plasma membrane integrity with an increased malondialdehyde (MDA) mycelial content was observed. Moreover, patulin production by P. expansum was reduced by ClO2 treatment, both in apples and in PDB meidium. These data showed new and precise clues to the inhibitory effect of ClO2 on P. expansum growth, and provided an effective method to ensure safety of apple products caused by P. expansum.