A Preliminary Study of Ozonation in the Outdoor Production of Strawberries (Fragaria X ananassa) to Suppress Gray Mold (Botrytis cinerea)

Summary

Gray mold (Botrytis cinerea) causes significant damage and yield losses in strawberry cultivation. Fungicides are widely used to control the disease. However, there is an increasing need for alternative treatments. We tested the use of micro-sprinklers versus a tractor mounted sprayer
for application of ozonated water to outdoor strawberry crops. Different application frequencies, ozone bubble sizes and volumes of ozonated water sprayed on the plants were also tested. The results showed that yields of healthy fruits by fresh weight and number were not increased by
ozone treatment compared to no treatment (2022: ozone macro bubbles treatment once a week: mean 3.43 kg SD ± 0.93, 269.7 fruits SD ± 54.9 - no treatment: mean 4.11 kg SD ± 0.37, 329.7 fruits SD ± 41.0). Fungicide use increased the fresh weight of healthy fruits and the number of fruits compared to ozone treatments (2022: fungicide treatment mean: 6.43 kg SD ± 1.12, 400.7 fruits SD ± 95.6). In these experiments, the application of ozonated water using both these methods didn’t suppress gray mold. The low efficiency of ozone in controlling the disease could be attributed to several factors. An optimization of the ozone water application method is needed.