Fungicide advice with the return of scab to South Georgia

摘要

Over the last several years we've gotten used to winning the battle with pecan scab fairly easily thanks to a multi-year drought; however, that has all changed this year. Not only have we had larger amounts of rainfall, but it has been more frequent,which really presents ideal conditions for the development of pecan scab.We have already seen the results of this with a higher incidence and severity of leaf scab throughout the state on susceptible varieties. Yet, I do see a lot of orchards that have very light or no scab on susceptible varieties. While some of the difference can be accounted for in the amount of scab pressure occurring at certain locations, the way fungicides have been used is accounting for some of the problems. I have seen orchards sprayed 3 times with less scab (or no scab) than orchards sprayed 7 times already (yes, there are orchards that have been sprayed 7 times by June 5) with the same varieties and similar rainfall. So, what's going on.