Wednesday, March 29, 2017

Apple scab and rust infection March 27-28

We recorded a 23-hr scab and cedar-apple rust infection period at our AREC March 27-28. Examination of rust galls indicated that cedar-apple rust basidiospores had discharged and some rust infection was likely. Apple bud stage ranged from 1/4-inch green tip to nearly open cluster on the most advanced varieties. Exposed blossoms are now also susceptible to quince rust. Hopefully, moderate wind conditions Thursday, March 30 will facilitate catching up with priority fungicide applications! 

Apple powdery mildew conidia were produced earlier this week, and March 30 will be a likely mildew infection day.