Bacon County Ag Update

I have had several discussions today regarding what actions are merited in light of last night’s freeze event.  The damage that we sustained last night coupled with the previous warm temperatures put blueberry plants in a high risk situation for fungal infections.   Conditions will be prefect for the next several days for Botrytis sporulation and rain events or moisture from overhead irrigation will increase the likelihood of Botryosphaeria issues.

 Below are some fungicide recommendations from Dr. Brannen

  1. Rabbiteyes (fully damaged). My understanding is that damage is often severe and producers may simply want to maintain bushes for next year at this time.  Rabbiteyes are generally less likely to have major Botryosphaeria issues, and I think the same is likely true for Botrytis as well.  I would consider an application of Captan (activity against Botrytis), but that might be it.  Producers will need to maintain leaves, so rust management or control of other leaf spots should be part of the plan going forward, but I would use cheap materials for leaf spot management.
  2. Rabbiteyes (in bloom). If maintaining bloom on rabbiteyes, I would recommend using Indar or Orbit or Quash or Proline for control of mummy berry (still out there), and I would suggest that one use either Captan, or Captan + Elevate or CaptEvate (Captan + Elevate comix product) tank- mixed with these DMIs. I would then follow suit with a regular spray program for the remainder of the season and going forward.
  3. Rabbiteye and southern highbush (fruiting). In this case, I would be more aggressive, and I would recommend an immediate application of Switch + Captan or Abound + Captan or Pristine + Captan.  I would then follow suit with a regular spray program for the remainder of the season and going forward.

ProGibb and rabbitteye crop resecue

 

The consensus seems to be that 25%-30% stage 5 flower buds that contain undamaged seeds, should be present before ProGibb should even be considered. Work done by Dr. Gerard Krewer, Dr. Scott Nesmith and Dr. Linstrom showed fruit set may be near  28%-30% at  26.6 F  when treated with two applications of ProGibb at 250ppm, but  fruit dropped to less than 2% at 23 F.   UGA Extension is not making a recommendation for or against ProGibb applications for crop rescue. I just wanted to provide you with information to assist your decisions.

Please call me if you need any assistance.  You can follow these links for a detailed letter on disease risk management guidelines from Dr. Brannen regarding disease risk and the journal article on ProGibb.

 

freeze damage disease management 2017

Fruit set of Freeze damaged blueberry