Effect of ozone water on strawberry and Pestalotiopsis

Through the tissue separation, purification and molecular biological identification technologies, it was confirmed that the pathogenic fungus which caused a new disease of strawberry leaves is Pestalotiopsis. Using pure water as a blank control, ozone waters of different concentrations were sprayed to pathogenic fungus directly and to strawberry leaf surface in its growing period.The concentration effects of ozone water on pathogenic fungus and strawberry leaves were studied respectively.The results showed that:lower concentration ozone water(0.5-0.8 mg · L-1) has little effect on the physiological and ecological changes of strawberry plants and on the growth of pathogenic fungus; medium concentration ozone water(2.2-2.5 mg·L-1) can significantly inhibit the growth of pathogenic fungus and promote the growth of strawberry; higher concentration ozone water(4.0-4.3 mg·L-1) can well inhibit the growth of pathogenic fungus.However,it has a serious corrosion effect on strawberry leaves.Therefore,the medium concentration(2.2-2.5 mg·L-1) is the most suitable ozone water concentration for spraying on strawberry, which can be used in practical production to effectively prevent and control strawberry fungal diseases.