Botrytis Year: Resources, Testing and Other Observations

(Updated: April 16, 2022, 12:07 p.m.)

Observations of the current Strawberry season in NC


 

Dear all,

I wanted to share a few observations of the still young strawberry season here in North Carolina. First, Botrytis is everywhere this year, mainly due to heavy row-cover use early on. Clemson University has re-established their pesticide resistant testing service ($100 for out-of-state samples). The submission form can be found here: (Clemson pesticide testing from).

a) This year is a Botrytis year.

Botrytis Grey-Mold (Figure 1) is unfortunately very common this year, due to the heavy row cover use early on and the many heavy rains we had in the past. However, I wanted to extend that we have several tools to manage Botrytis and Anthracnose.



 

Figure 1: Botrytis grey mold on strawberry fruit in NC.

B) Important: Pesticide Resistance Testing has been re-established


 
Clemson University has re-established the popular pesticide resistance testing service for Botrytis.

Please print out THIS FORM (PDF). You will notice two panels. One for one set of chemicals and one for another set. The idea, though, is that both panels are requested for getting the full picture. Splitting this up was for technical (inhouse) reasons to be able to provide this service at a reasonable price before this year’s season is over. The instate price (South Carolina) for the complete service is $80. For out of state customers it is $100.


We have not been provided with sampling instructions yet. You can use any symptomatic tissue or swipe spores on cotton swabs. Make sure you send enough to test 10 isolates per sample (approx. 20 samples of infected leaf tissue, 15 fruit samples, 25-30 cotton swaps). Please reach out to ppclnc@clemson.edu for more information. We will update you if we have better sampling instructions.


Samples and form needs to be send to:

Molecular Pathogen and Pest Detection Lab

511 Westinghouse Rd.

Pendleton, SC 29670

864-646-2133; ppclnc@clemson.edu


 
 

C) Glyphosate Damage and Phyllody


 

No related to Botrytis, but still an observation. Drift of Glyphosate can happen, especially on strawberry rows on edges or if Glyphosate is used in row middles. Affected strawberry plants will then underproduce, and often phyllody (Figure 2) can occur on fruit from damaged plants. The fruit in  figure 2 were collected in a row that accidentally was affected by Glyphosate several weeks ago.

Figure 2: Phyllody on strawberry fruit, caused by prior glyphosate exposure