Botrytis Control In Berries Key project cooperators Alan Schreiber, Agriculture Development Group, Inc Jim Adaskaveg, University of California, Riverside Tom Walters, Walters Ag Research Steve Midboe, Whatcom Farmers Coop Chris Clemons, Syngenta Crop Management Tom Peerbolt, Peerbolt Crop Management
Members of the Botrytis resistance working group Jim Adaskaveg, University of California-Riverside Jay Pscheidt, Oregon State University Steve Midboe, Whatcom Farmers Coop Brian Cieslar, Curt Maberry Packing, Enfield Farms Kevin Berendsen, Enfield Farms Leighton Overson, Whatcom Farmers Coop, WBC R C Chair Henry Bierlink, Washington Red Raspberry Commission Tom Peerbolt, Peerbolt Crop Management Layne Wade, Arysta LifeSciences Chuck Rice, BASF Christopher Clemens, Syngenta Crop Protection Alan Schreiber, Washington Blueberry Commission, Agriculture Development Group, Inc.
Vocabulary Words Botrytis cinerea is gray mold Brand name = common name Elevate = fenhexamid Captan = captan Pristine = boscalid (and another product) Switch = cyprodinil + fludioxinil Rovral = iprodione Bravo, Echo = chlorothalonil
Berries, raspberries in particular, have a history of developing resistance to fungicides used for its control. The primary products used for control of botrytis in raspberry in 2012 were Captan, Pristine, Switch and Elevate. Products previously used to control botrytis were not giving the level of control that they previously did. Whatcom County Farmers Coop (Midboe), Syngenta Crop Protection (Clemons) worked with a University of California fruit pathologist (Adaskaveg) to determine whether fungicides were as effective as they have been in the past. They collected samples from nine Whatcom County raspberry fields and tested them against the fungicides contained in Pristine, Switch and Elevate.
Whatcom Botrytis Resistance in Raspberry Survey Results in 2012. Every sample of botrytis showed resistance to Elevate. 12% of samples showed resistance to one component of Switch. 0% of samples of the second component of Switch showed resistance. 15% of samples showed resistance to Pristine. Fields that had Captan in their rotation had lower levels of resistance to all fungicides than did fields that did not use Captan. This was a very, very serious situation. If the Whatcom Country berry industry does not immediately change its disease control practices, every raspberry grower is at risk of losing their ability to control botrytis. This condition is likely to jump to blueberries and strawberries.
Botrytis on raspberry, blueberry and strawberry is the same disease. Presumably it moves back and forth between crops. Growers use many of the same fungicides against the same disease on these three crops.
One of the issues that makes this situation so serious is that there are no new types of fungicides coming that will solve this problem. We have to make the products that we currently have; work for us. We have to manage resistance-something that has been difficult to do in other crops.
What we expect growers/consultants to do. The Washington Red Raspberry Commission and the Washington Blueberry Commission has formed a working group to develop recommendations on how to control botrytis and manage resistance to fungicides and support research on how to deal with the situation. Survey raspberries, blueberries and strawberries throughout western Washington to determine the extent and severity of fungicide resistance in botrytis. Oversee research to develop new means to control the disease.
Draft Recommendations for Botrytis control in raspberries Do not use Elevate in 2013. We need to not use the product in order to save it for future use. Bring back Rovral (iprodione) for limited use in 2013. Add Captan to every botrytis application if you can. Limit use of Pristine to one application per season. Limit use of Rovral to one application per season. Do everything you can to get good coverage, such as use 100 gallons per acre. Slow sprayers down. Make sure sprayers are calibrated and in good condition. Do not cut rates-use the full rate.
We did a limited survey of botrytis on berries in 2013 to test for resistance to commonly used fungicides. Midboe collected samples from Whatcom. Walters collected samples from Skagit. Peerbolt collected samples from SE WA And then Peerbolt snuck into Oregon without telling any of us and collected samples from one grower. Samples were sent to Jim Adaskaveg at UC Riverside, who tested the samples for resistance to a number of diseases.
Table 1. In vitro sensitivity of Botrytis cinerea isolates from raspberry canes to Elevate, Switch (half), iprodione, and Pristine from Whatcom 2013, preseason. EC 50 (ppm) Elevate Switch (half) Iprodione Pristine 3.31 0.040 0.130 0.86 1.95 0.034 0.146 0.81 2.32 0.036 0.155 1.10 1.63 0.026 0.081 0.36 2.77 0.079 0.109 1.57 2.32 0.079 0.096 1.23 16.24 0.060 1.196 1.10 2.46 0.063 0.096 0.32 2.32 0.040 0.064 0.34 1.37 0.084 0.141 0.55 >40 0.032 0.683 0.64 4.71 0.026 0.264 0.57 3.95 0.576 1.001 32.66 1.45 0.056 1.516 0.58 2.06 0.038 0.943 0.38 1.21 1.494 0.661 >40 1.29 0.545 0.388 24.25 >40 0.060 0.934 0.55 0.006 0.034 0.356 0.52 3.95 0.053 0.650 11.87 1.73 0.036 1.10 1.45 0.036 0.235 1.31 >40 0.682 0.436 >40 2.46 0.048 0.214 0.70 1.63 0.954 0.146 30.77 1.21 0.040 0.133 0.99 3.31 0.060 0.060 0.86 4.19 0.099 0.365 1.57 >40 0.038 0.990 0.48 >40 0.030 0.660 1.23 >40 0.034 0.093 0.52
Table 1. In vitro sensitivity of Botrytis cinerea isolates from raspberry canes to Elevate Switch (half), Iprodione, and Endura EC 50 (ppm) No. ID No. Origin of sample Field Elevate Switch (half) Iprodione Pristine 85 10-1 10 S 0.034 0.057 86 10-2 No Elevate 0.015 0.050 0.934 0.55 87 10-3 4.44 0.117 0.138 4.31 88 10-4 0.012 0.050 0.091 4.58 89 10-5 0.009 0.105 0.076 0.52 90 10-6 1.29 0.030 0.146 1.48 91 10-7 0.026 0.063 0.990 0.66 92 10-8 0.015 0.050 0.115 1.76 93 10-9 0.017 0.040 0.076 2.38 94 11-2 11 0.008 0.063 0.115 3.20 95 11-3 No Elevate 0.008 0.067 0.076 1.99 96 11-4 0.013 0.063 0.091 1.87 97 11-6 1.73 0.117 0.316 0.83 98 11-7 0.010 0.048 0.491 0.38 99 11-9 0.020 0.060 0.045 1.10 100 11-10 0.008 0.019 0.072 1.87
Table 2. In vitro sensitivity of Botrytis cinerea a isolates from raspberry to Elevate, Switch (half) Pristine, Iprodione, and Bravo in Skagit County preseason. EC 50 (ppm) Elevate Switch (half) Prstine Iprodione Bravo, Echo 0.01 1.93 6.54 0.13 0.56 0.01 0.01 0.11 0.05 0.20 0.01 0.01 0.15 0.04 0.31 0.01 0.01 0.13 0.10 0.39 0.12 1.93 1.99 0.28 2.64 0.01 0.01 0.12 0.04 0.23 0.04 0.05 1.31 0.25 3.32 0.04 0.02 2.84 0.23 0.99 0.06 0.27 1.31 0.21 1.76 0.01 1.17 11.18 0.57 0.39 0.08 0.88 5.15 0.28 1.76 0.01 0.02 0.18 0.61 0.42 0.01 1.38 >40 0.26 0.53 0.01 0.34 7.37 0.15 0.28 0.01 0.03 0.64 0.03 0.47 0.01 0.02 0.23 0.13 0.39 0.01 0.40 8.30 0.15 0.50 0.01 0.01 0.11 0.07 0.33
Table 3. In vitro sensitivity of Botrytis cinerea isolates from raspberry and strawberry to Elevate, Switch (half), Pristine, iprodione, and Bravo/Echo from SE Washington EC 50 (ppm) Location Isolate Elevate Switch (half) Pristine Iprodione Chlorothalonil Strawberry 1 0.01 0.10 0.35 0.11 0.83 2 0.01 0.12 0.23 0.07 0.66 3 0.01 0.11 0.37 0.07 0.88 4 0.01 0.11 0.30 0.07 0.66 5 0.01 0.08 0.33 0.08 0.50 6-17 - No isolates recovered - Raspberry 1-9 - No isolates recovered -
Table 4. In vitro sensitivity of Botrytis cinerea isolates from blueberry to Elevate, Switch (half), Pristine, iprodione,and chlorothalonil in Whatcom County preseason. EC 50 (ppm) Elevate Switch (half) Pristine Iprodione Chlorothalonil 0.01 0.46 >40 0.62 0.75 0.01 0.02 0.21 0.11 0.91 0.01 0.06 >40 0.11 0.50 0.01 0.07 >40 0.23 0.74 0.01 0.02 0.21 0.26 0.75 0.01 0.08 >40 0.23 0.89 0.01 0.07 >40 0.21 0.70 0.01 0.15 >40 0.54 0.85 0.01 0.03 0.33 0.12 1.06 0.01 0.01 0.12 0.05 0.42 0.01 0.09 >40 0.11 0.44 0.01 0.02 0.25 0.10 0.53 0.00 0.02 0.13 0.03 0.35 0.01 0.39 >40 0.07 0.31 0.01 sensitive >40 0.08 0.28 0.01 0.01 0.11 0.04 0.30 0.01 0.01 0.18 0.12 0.35 1.15 0.02 >40 0.32 0.44 0.01 0.01 0.17 0.04 0.39
Table 5. In vitro sensitivity of Botrytis cinerea isolates from berry crops from one farm in Oregon to Switch (the other half), Elevate, Switch (half), iprodione, and Pristine. EC 50 (ppm) Origin fludioxonil (Swi) Elevate cyprodinil (Swi) iprodione Pristine Blueberry 0.009 0.120 1.313 1.004 16.36 0.014 0.075 0.974 0.665 10.34 0.024 0.049 3.974 1.452 5.48 0.006 0.009 0.187 0.183 10.61 0.049 0.057 0.691 1.565 18.30 0.012 0.102 0.242 1.062 5.82 0.008 0.012 0.487 0.201 5.10 0.012 0.073 0.068 0.829 20.61 0.019 0.013 0.870 0.443 14.82 0.019 0.018 0.956 0.375 14.42 0.011 0.024 0.545 0.458 3.27 0.004 0.013 0.333 0.100 0.19 Strawberry 0.010 3.872 0.085 1.141 3.68 0.015 0.107 3.905 0.732 8.16 0.019 0.084 5.490 1.129 16.01 0.021 0.069 1.596 0.513 17.09 0.026 30.136 0.581 1.255 5.07 0.026 0.016 1.330 0.233 10.80 0.018 0.157 0.176 1.412 >30 Raspberry 0.006 0.031 0.017 0.159 0.14 0.013 0.013 0.778 0.388 2.72 0.019 >40 1.123 1.708 7.73 0.010 0.014 2.124 0.310 22.92 0.024 0.027 6.314 0.393 14.42
We needed data on what fungicides worked against resistance botrytis. Applications made by WSU: Carol Miles, Tom Walters, Don Wallace, Jeremy Cowan and Kyle Craig. Schreiber did mid season evaluations. Tom Walters did harvest evaluations and end of season evaluations. Two trials: half season trial, 3 applications, testing a lot of new products, sort of a preliminary screen; second trial is a full season trial, 6 applications, with mid and end of season evaluation with yield data. 18 treatments and 24 treatments; a tremendous amount of work. Trial was in a commercial raspberry field with documented resistance to three fungicides.
Results from field efficacy trial First application was made prebloom. First half of the season was very conducive to botrytis. Second half of the season was quite dry and very unconducive to botrytis. Mid season evaluations were useful. End of season evaluations and yield data generated little useful data due to lack of disease pressure.
Comparison of 18 Treatments for Botrytis Control in Raspberry Based on 3 applications made in field conditions in Whatcom Co. in 2013. Trt Treatment Rate # of % incidence Disease No Name Of Application Appls. of botrytis Severity 0-5 1 Untreated 0.20 a 3.50 a 18 Jet AG/Jet AG/Jet AG 10 oz wt/10 gal ABC 0.18 a 2.29 abcd 15 Regalia/Regalia/Regalia 2 qt/a ABC 0.11 b 2.94 ab 17 Regalia+Endof/Reg+Endof/Reg+Endofine 2+2 qt+lb/a ABC 0.10 bc 2.03 abcd 5 Omega/Omega/Omega 1.3 fl oz/a ABC 0.08 bcd 2.78 ab 9 Regalia/Regalia/Regalia 4 qt/a ABC 0.08 bcd 2.70 abc 3 Elevate/Elevate/Elevate 4 oz/a ABC 0.05 bcde 1.83 abcd 4 PhD/PhD/PhD 6.2 oz/a ABC 0.05 bcde 1.50 bcde 6 LUNA/LUNA/LUNA 5.5 fl oz/a ABC 0.05 bcde 0.77 de 10 Bravo+Captan/Pristine+Captan/Switch+Cap ABC 0.04 cde 0.88 de 8 PhD/PhD/PhD 12 oz/a ABC 0.03 de 0.88 de 2 Captan/Pristine/Switch+Captan lb/a ABC 0.01 de 1.00 cde 7 Merivon/Merivon/Merivon 5.5 fl oz/a ABC 0.00 e 0.00 e 11 Lime Sulfur+Captan/Pristine+Cap/Swit+Cap ABC 0.00 e 0.00 e 12 PhD/PhD/PhD 16 oz/a ABC 0.00 e 0.00 e 13 Proline/Proline/Proline 5 fl oz/a ABC 0.00 e 0.00 e 14 Propulse/Propulse/Propulse 12 fl oz/a ABC 0.00 e 0.00 e 16 Regalia+Quadris/Regalia+Quad/Reg+Quad 2+6 qt+oz/a ABC 0.00 e 0.00 e Red means the program contains products not registered on raspberry.
Comparison of 24 Season Long Programs for Botrytis Control in Raspberry Trt Treatment Appl % disease disease # Name Code incidence severity (0-5) 1 UNTREATED CHECK 22.50 a 2.13 ab 20 REGALIA+Endofine (six times) ABCDEF 15.00 b 1.95 abc 16 REGALIA six times ABCDEF 11.25 bc 2.03 ab 14 Experimental compound 1 (six times) ABCDEF 10.00 bcd 1.58 abc 17 Experimental compound 1 (six times) ABCDEF 10.00 bcd 2.70 a 15 ELEVATE six times ABCDEF 7.50 bcde 1.43 abc 24 Experimental compound 2 + Captan (six times) ABCDEF 7.50 bcde 2.13 ab 18 REGALIA six times ABCDEF 6.25 cde 1.38 abc 21 Experimental compond 2 (six times) ABCDEF 6.25 cde 1.63 abc 10 Cap/Pristine+Regalia/Switch+Reg/Pri+Reg/Swi+Reg/Elevate+Reg ABCDEF 3.75 cde 0.88 abc 22 Experimental compound 2 (six times) ABCDEF 3.75 cde 0.65 bc 13 Experimental compound 1 (six times) ABCDEF 3.33 cde 0.50 bc 3 Captan/Pristine/Switch/Pristine/Switch/Elevate ABCDEF 2.50 de 1.75 abc 6 Captan/Elevate/Iprodione/Switch/Pristine/Switch ABCDEF 2.50 de 1.25 abc 12 Experimental compound 1 (six times) ABCDEF 2.50 de 0.50 bc 19 REGALIA with Quadris (six times) ABCDEF 2.50 de 0.50 bc 11 Captan/Omega+Pristine/Omg+Swi/Omg+Pri/Omg/Swi/Omg+Elevate ABCDEF 1.67 e 1.00 abc 5 Captan/Iprodione/Switch/Pristine/Switch/Elevate ABCDEF 1.25 e 0.25 bc 23 Experimental compound 2 + Captan (six times) ABCDEF 1.25 e 1.00 abc 2 Captan/Cap+Pristine/Cap+Switch/Cap+Pri/Cap+Swi/Cap+Elevate ABCDEF 0.00 e 0.00 c 4 Chlorothalonil/Chlo+Switch/Pristine+Cap/Chlo+Swi/Pri+Cap/Ele+Cap ABCDEF 0.00 e 0.00 c 7 Captan/Pristine+PhD/Switch+PhD/Pri+PhD/Swi+PhD/Elevate+PhD ABCDEF 0.00 e 0.00 c 8 Captan/Luna/Switch/Luna/Switch/Luna ABCDEF 0.00 e 0.00 c 9 ECHO/Echo+Swi/PhD/PhD/Pri+Cap/Elevate ABCDEF 0.00 e 0.00 c Red means the program contains products not registered on raspberry.
Efficacy Trial Results Summary Before results can be summarize we need to have our working group to digest the results. I can say that in 2012, a year of very heavy disease pressure, products such as Endura, Elevate and Pristine had problems controlling botrytis. In our trial in 2013, a year of moderate to low disease pressure, those products worked better. Tank mixes worked well. Six application control programs worked. With the exception of PhD, no new single product that is registered on raspberry commercially acceptable control.
Resistance Survey Results Resistance is ALWAYS local. It is caused by fungicide use practices within and between adjacent fields. If you have fungicide resistance it was caused by your application practices. Significance differences within Whatcom County, between Whatcom, Skagit and Clark counties, between Washington and Oregon. All crops have resistance problems. Significant differences between raspberry, blueberry and strawberry. Without serious consideration of using a resistance management plan, resistance always gets worse. In most cases, I believe if you know what you are doing and have a competent crop advisor you can deal with botrytis resistance in your berry crop. If you did not see your crop advisors business name in our working group, I suggest you put them in touch with me.
Recommendations for 2014 Much of this data was just provided to me a couple of days ago. Our pest management group has not seen or had time to digest this information and we have not yet decided what to do. Our working group needs to meet, review the results and develop recommendations. For now, talk to your local crop advisor.
Plans for 2014 Dr. Tobin Peever, a real plant pathologist and hopefully heir apparent to Dr. Pete Bristow, is now on the scene and is will have the lead on berry disease research in Washington. He will have the lead on the resistance and biological aspects of the botrytis project. Schreiber, with support from Walters and Peever, plans to generate more efficacy data. The results generated so far have been striking and significant, but have only scratched the surface and have generated more questions than answers The results have set the stage for some very useful and important research in 2014.