Ozone controls potato dry rot development and diacetoxyscirpenol accumulation by targeting the cell membrane and affecting the growth of Fusarium sulphureus

Fusarium sulphureum is a major plant pathogenic fungus that can cause dry rot of potato. Ozone, a strong oxidant, is generally regarded as a safe (GRAS) substance to widely use to manage postharvest decay in fruit and vegetables. The effect of ozone treatment on the mycelia growth, spore germination, cell membrane integrity and morphological and ultrastructural alteration, as well as intracellular reactive species oxygen (ROS) generation of F. sulphureum in vitro , and dry rot development and diacetoxyscirpenol (DAS) in vivo was conducted. Results demonstrated 2 mg L −1 ozone treatment effectively inhibited mycelia growth and spore germination, disturbed the cell membrane integrity of F. sulphureum in vitro due to intracellular ROS production , moreover, ozone lead to morphological alteration such as obvious shriveled and sunken on the surface, even some broken fragment was observed; transmission electron microscopy observation suggested some organelles such as, cytoplasm mitochondria and cell wall were suffered serious destruction. The inhibitory efficacy on F. sulphureum spore, as a consequently, lead to the suppressing the dry rot and DAS accumulation in vivo . • 2 mg L −1 ozone significantly inhibited mycelial growth and spore germination of F. sulphureum. • Ozone disturbed cell membrane integrity by reactive species oxygen generation. • Ozone changed mycelial morphology and ultrastructure of F. sulphureum . • Ozone treatment suppressed dry rot development and diacetoxyscirpenol (DAS) in inoculated potato tuber.