Vine Crop Edition, by Elaine Roddy,
Vegetable Crop Specialist (elaine.roddy@ontario.ca)
Downy Mildew Spores Trapped in Michigan
The June 10th edition of Michigan State University’s IPM News reports that significant numbers of downy mildew spores were caught in Munroe County last week. Munroe County is in the south-eastern corner of Michigan. These spore traps are part of the research program conducted by Dr. Mary Hausbeck at MSU. Dr. Hausbeck’s article is available at: http://www.ipmnews.msu.edu/vegetable/vegetable/tabid/151/articleType/ArticleView/articleId/487/High-number-of-downy-mildew-sporangia-detected-in-Monroe-County.aspx
Ontario growers should be actively monitoring all cucumber fields for signs of downy mildew and following a preventative fungicide spray program. Targeted downy mildew fungicides (listed below) provide a higher level of control in the unsettled weather conditions we are currently experiencing.
Table 1. Recommended Fungicides for Cucurbit Downy Mildew Control
|
Fungicide |
Chemical Family |
Rate |
PHI |
Notes |
|
Targeted Downy Mildew Fungicides |
|
cyazofamid
Ranman 400SC |
21 |
150-200 mL/ha
(60-80 mL/acre) |
1 |
12 hour re-entry interval. Maximum 6 applications per year. Use the high rate on a dense canopy or under high risk conditions.
Use 150 mL/ha (62 mL/ac) of Sylgard 309 as a surfactant. |
|
propamocarb/
chlorothalonil
Tattoo C |
28/M5 |
1.2-2.7 L/ha(0.72-1.1 L/acre) |
2 |
Use the high rate on a dense canopy or under high risk conditions.
Maximum 5 Applications per year. |
|
Broad Spectrum Downy Mildew Fungicides |
|
mancozeb
Dithane DG or
Manzate DF or
Penncozeb 80 WP |
M2 |
1.1-3.25 kg/ha(0.44-1.3 kg/acre) |
14 |
Ensure thorough spray coverage. |
|
chlorothalonil
Bravo 500
|
M5
|
4.8 kg/ha
(1.9 L/acre)
|
1 |
Ensure thorough spray coverage. Maximum 7 applications per year.
|
Questions? Comments?
Give me a call at 519-674-1616
or email elaine.roddy@ontario.ca
|
