The possibility of a chlorothalonil (Bravo and generics) shortage came up at the Savannah Fruit and Vegetable Meeting last week, and though it is not expected to be as short as last year, that is still a real concern.  Abound is always a good replacement for chlorothalonil, and it would definitely give equivalent if not moderately better efficacy as part of a comprehensive scab program.  However, we would still prefer that we not utilize Abound on a regular basis during the petal fall or shuck split timeframes due to the potential for scab and brown rot resistance development.  Use of Abound in one year alone will not likely result in resistance, so producers should feel free to use it this year if they feel this is their best choice in the absence of chlorothalonil.  Captan, when applied at higher rates as part of a full scab program, actually provides good efficacy against peach scab.  It is difficult to find good head-to-head comparisons of Captan, Bravo, and Abound in the literature, but rankings are always pretty similar if the high rate of Captan is utilized; I am not sure of the cost comparisons, but if utilizing Captan for scab at the petal fall / shuck split (critical) phenology, I would utilize the maximum rates if economically feasible.    Sulfur is not sufficiently efficacious for use in petal fall / shuck split timeframes, though if we had nothing other than sulfur, it will often give pretty good results.  I hope this information will be of value if the potential shortage of chlorothalonil is of concern to your commercial peach producers.

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