SoCal botrytis plague 2011

[Dr. Detroit]

I do a lot of professional diagnosis in the Southern California area and there seems to be a serious botrytis (grey mold) infection happening here presently. They seem to be mainly spread by whitefly's acting as vectors, though the presence of two-spotted spider mites on many of the surveyed plants could also suggest that they are the Typhoid Mary's this season.

A botrytis infection can decimate a garden in under a week if left untreated. I remove the infected tissue and all surrounding tissue, being careful to upset the spores as little as possible.

Available sprays like Serenade are reportedly effective, but the smell of that stuff makes it unlikely to be useful indoors or near anyone that dislikes the smell of rotting dog poop on a moist warm floor...

 

[Blaze]

Been seeing a tremendous amt here in NorCal this year too. The usual counters like serenade, sonota, stylet, oxidate, etc don't seem to be stopping it very well either. Interesting you mention white flies as the vector - I saw them in my area for the first time outdoors this year.

 

[wintergreens]

Up here in WesternWa i to have had some mold, did see white flies to.

 

[phenotyper]

I use serenade and the smell fades pretty rapidly. Well worth an organic control with zero PHI.

 

[Dr. Detroit]

Whitefly's are the only obvious common factor with all of these different gardens that I've been seeing. There's no way to positively identify them as the vectors for this pathogen, but my theory is that they are.

The fact that they appeared out of nowhere this year after being a minor and rare visitor for the last several years makes me suspect some sort of endemic environmental factor is causing their appearance. While they're nearly harmless, they do carry pathogens that spread when they rupture the plant's cell walls to feed, making them incredibly harmful. A mosquito may be a minor inconvenience, but the malaria that they can carry is deadly.

 

[Blaze]

I think your theory is accurate. You describe exactly what I saw this year. Never hardly seen any white flies before, then all of a sudden about 4 weeks ago I started seeing them everywhere out of the blue. Two weeks after that I started finding some botrytis on a few plants. This really puzzled me as I have NEVER seen botrytis that early in the year at my spot, the weather had been warm and dry, and the buds were not even all that big or dense at that point. Seems like the humid weather we got about 2 weeks ago really accelerated it too - I hit 90% humidity one day which has never, ever, EVER happened in the 20+ years I've lived in this area. Going to be trying a new product in a few days specifically for botrytis, I'll let you guys know if it works.