The relationship between SO2 Ct products and gray
mold prevalence under laboratory conditions was best explained by exponential models, which had a
determination coefficient (R2) that ranged from 0.88 to 0.96. The estimated EC90 values varied between
245 and 400 (L L−1) h, and the SO2 Ct between 250 and 350 (L L−1) h was validated using a pallet scale
application treatment to obtain the best control and minimal variation. No visual phytotoxicity symptoms
of SO2 were observed with the Ct that was tested in this study. Therefore, SO2 fumigation was
demonstrated to be an effective and practical technology for reducing the risk of blueberry gray mold
decay during storage, and further effort should be given to register the use of this product for blueberries
in the main Chilean export markets.