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Table 1 from:


Wyenandt, C. A., Ward, D. L., and Maxwell, N. L. 2010. Determining “practical” fungicide resistance development and drift in the control of cucurbit powdery mildew in pumpkin. Online. Plant Health Progress doi:10.1094/PHP-2010-1122-02-RS.



Table 1. Active ingredients, FRAC code, and percent cucurbit powdery mildew severity on adaxial and abaxial leaf surfaces of pumpkin cultivar Howden treated with nine selected fungicides following five different season-long fungicide programs in 2006 and 2007 at the Rutgers Agricultural Research and Extension Center, Bridgeton, NJ.

Active ingredients applied
to bioassay plants
w
FRAC
code
2006 season-long fungicide programs and leaf surfacez
Protectants
only
Group 3
alt. 11
Group 3
alt. 11 + 27
Group 3
weekly
Group 11
weekly
Adx Abx Ad Ab Ad Ab Ad Ab Ad Ab
sulfur M1 0y 8 0 1 1 1 0 9 0 3
myclobutanil + chlorothalonil 3 + M5 0 0 0 0 0 0 0 0 0 0
famoxadone + cymoxanil 11 + 27 15 10 85 11 83 25 43 18 12 3
myclobutanil 3 0 0 0 1 0 0 2 1 0 0
azoxystrobin 11 94 26 93 12 77 7 90 56 95 73
pyraclostrobin + boscalid 11 + 7 8 5 4 2 6 3 8 1 4 1
pyraclostrobin 11 75 9 91 18 18 10 46 16 73 4
quinoxyfen 13 0 0 0 0 0 0 0 0 0 0
chlorothalonil M5 19 15 31 9 26 9 60 18 83 68
control (water only) 80 6 7 19 58 6 75 12 95 56
Active ingredients applied
to bioassay plants
w
FRAC
code
2007 season-long fungicide programs and leaf surfacez
Protectants
only
Group 3
alt. 11
Group 3
alt. 11 + 27
Group 3
weekly
Group 11
weekly
Adx Abx Ad Ab Ad Ab Ad Ab Ad Ab
sulfur M1 9y 8 25 3 18 1 10 16 7 10
myclobutanil + chlorothalonil 3 + M5 5 5 2 0 2 0 0 0 1 2
famoxadone + cymoxanil 11 + 27 73 24 62 8 39 10 68 38 53 28
myclobutanil 3 2 1 0 0 0 0 3 4 10 5
azoxystrobin 11 87 58 67 13 52 7 76 30 64 24
pyraclostrobin + boscalid 11 + 7 1 0 2 0 12 5 3 3 3 2
pyraclostrobin 11 83 14 41 4 30 14 28 8 75 48
quinoxyfen 13 0 0 0 0 0 0 0 0 0 0
chlorothalonil M5 73 35 35 3 37 12 23 4 67 12
control (water only) 43 15 73 22 75 17 37 10 23 5

 w Active ingredient rates applied to run-off on bioassay plants were: sulfur at 2.24 kg/ha; myclobutanil at 0.35 kg/ha; chlorothalonil at 3.5 liters/ha; famoxadone + cymoxanil at 0.56 kg/ha; myclobutanil at 0.35 kg/ha; azoxystrobin at 0.35 kg/ha; pyraclostrobun + boscalid at 1.30 kg/ha; pyraclostrobin at 0.84 kg/ha; quinoxyfen at 0.29 liters/ha; or control (distilled water only).

 x Ad = adaxial, Ab = abaxial.

 y Mean powdery mildew severity on the adaxial and abaxial surfaces of three leaves from each fungicide treated potted plant. Powdery mildew severity was rated on a scale of 0.0 to 100.0 (where 0.0 = none, 100 = 100%) (i.e., percentage of adaxial or abaxial of leaf surfaces with symptoms of powdery mildew).

 z The five season-long fungicide programs were: protectants only (2.24 kg/ha manzate + 2.24 kg/ha sulfur alternated weekly with 2.24 kg/ha maneb + 1.51 liters/ha copper hydroxide); Group 3 alt. 11 (3.5 liters/ha chlorothalonil + 0.35 kg/ha myclobutanil alternated weekly with 0.35 kg/ha azoxystrobin); Group 3 alt. weekly with 11 + 27 (2.24 kg/ha maneb + 0.35 kg/ha myclobutanil alternated weekly with 0.56 kg/ha famoxadone + cymoxanil); Group 3 weekly (3.5 liters/ha chlorothalonil + 0.35 kg/ha myclobutanil alternated weekly with 0.35 kg/ha myclobutanil); Group 11 weekly (3.5 liters/ha chlorothalonil + 0.35 kg/ha azoxystrobin alternated weekly with 0.35 kg/ha azoxystrobin).





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