Scab and rust infection period

An apple scab and possible cedar-apple and quince rust infection period was recorded with 20-hr wetting from 2 AM-10 PM Apr 16. Temperatures through the wetting period ranged from 47-58F at the AREC but were as much as 4 degrees warmer in Winchester. Blossoms are now highly susceptible to quince rust. The 1.8-in. rainfall would have depleted most of the residue of non-systemic protectant fungicides applied this week, but an SI fungicide applied Apr 14-15 would have controlled any rust infection that occurred in this wetting period as well as the one Apr 12-13.