Peanut Leaf Spot Advisories for Sept 14

This year many growers applied a fungicide just before Hurricane Irene.  It has now been about two weeks since that application was made. Unless a field is nearly ready for digging, an additional fungicide application may be necessary to carry protection though the end of the season.

Additional foliar fungicide sprays could also be necessary if digging will be delayed due to earlier drought stress – or if we have another tropical storm.

Growers who want to continue a calendar schedule should apply a spray if it has been more than two weeks since the last fungicide application.

The best way to determine whether a late-season spray is needed is to watch leaf spot advisories, even if a calendar spray schedule was used throughout the summer.

Either way, use a broad-spectrum fungicide such as Bravo (chlorothalonil) for the final spray.  Some growers have been interested in mixing Bravo and Headline for the last spray. While not as risky as using Headline alone, there still is a fungicide resistance risk with this approach because Headline persists longer than Bravo. . Here are some guidelines for resistance management in late season:

• The best way to prevent fungicide resistance is to use Bravo (or generic equivalent) as the last spray
• If you have maintained good leaf spot control all season, there is little reason to add anything to Bravo for a final spray
• Do not use any group 3 (tebuconazole, Provost) or group 11 (Headline, Abound, Evito) fungicide as the last spray unless it is mixed with Bravo (or generic)
• Do not use a Bravo + Headline mixture as the last spray if digging is not anticipated within two weeks. A follow-up application of Bravo will be necessary for longer intervals.
• Do not make more than two applications of any group 11 fungicide per season.

September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR BUCK Buckland Elementary (Buckland, NC) setDate = 2011-09-06 07:00:00 lethal conditions = false favorable hours = 49 LESD = 2011-08-31 BUCK Advisory: spray today Growing degree days (base 56 F) since LESD = 275.4 Growing degree days (base 56 F) since May 1 = 2380.8 Records count: 192 out of 193 Most recent db ob to 8am EDT: 2011-09-14 07:00:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR CLIN Horticultural Crops Research Stn (Clinton, NC) setDate = 2011-09-06 07:00:00 lethal conditions = false favorable hours = 27 LESD = 2011-08-26 CLIN Advisory: do not spray today Growing degree days (base 56 F) since LESD = 389 Growing degree days (base 56 F) since May 1 = 3006.1 Records count: 192 out of 193 Most recent db ob to 8am EDT: 2011-09-14 07:00:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR KINS Cunningham Research Station (Kinston, NC) setDate = 2011-08-30 07:00:00 lethal conditions = false favorable hours = 45 LESD = 2011-08-19 KINS Advisory: do not spray today Growing degree days (base 56 F) since LESD = 549.9 Growing degree days (base 56 F) since May 1 = 2986.1 Records count: 360 out of 361 Most recent db ob to 8am EDT: 2011-09-14 07:00:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR LEWS Peanut Belt Research Station (Lewiston, NC) setDate = 2011-09-09 07:00:00 lethal conditions = false favorable hours = 42 LESD = 2011-08-29 LEWS Advisory: do not spray today Growing degree days (base 56 F) since LESD = 312.7 Growing degree days (base 56 F) since May 1 = 2812.8 Records count: 120 out of 121 Most recent db ob to 8am EDT: 2011-09-14 07:00:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR PLYM Tidewater Research Station (Plymouth, NC) setDate = 2011-08-24 07:00:00 lethal conditions = false favorable hours = 24 LESD = 2011-08-13 PLYM Advisory: do not spray today Growing degree days (base 56 F) since LESD = 647.7 Growing degree days (base 56 F) since May 1 = 2777.7 Records count: 504 out of 505 Most recent db ob to 8am EDT: 2011-09-14 07:00:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR ROCK Upper Coastal Plain Res Stn (Rocky Mount, NC) setDate = 2011-09-10 07:00:00 lethal conditions = false favorable hours = 21 LESD = 2011-08-30 ROCK Advisory: do not spray today Growing degree days (base 56 F) since LESD = 308.3 Growing degree days (base 56 F) since May 1 = 2703.1 Records count: 95 out of 97 Most recent db ob to 8am EDT: 2011-09-14 06:00:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR WHIT Border Belt Tobacco Res Stn (Whiteville, NC) setDate = 2011-09-09 07:00:00 lethal conditions = false favorable hours = 33 LESD = 2011-08-29 WHIT Advisory: do not spray today Growing degree days (base 56 F) since LESD = 325.5 Growing degree days (base 56 F) since May 1 = 2973.8 Records count: 120 out of 121 Most recent db ob to 8am EDT: 2011-09-14 07:00:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR WILL Highway Patrol Comm Station (Williamston, NC) setDate = 2011-09-10 07:00:00 lethal conditions = false favorable hours = 14 LESD = 2011-08-30 WILL Advisory: do not spray today Growing degree days (base 56 F) since LESD = 301.3 Growing degree days (base 56 F) since May 1 = 2823.1 Records count: 95 out of 97 Most recent db ob to 8am EDT: 2011-09-14 06:00:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR KSFQ Suffolk Airport (Suffolk, VA) setDate = 2011-09-06 07:00:00 lethal conditions = false favorable hours = 49 LESD = 2011-08-31 KSFQ Advisory: spray today Growing degree days (base 56 F) since LESD = 289.5 Growing degree days (base 56 F) since May 1 = 2766 Records count: 189 out of 193 Most recent db ob to 8am EDT: 2011-09-14 05:55:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR KECG Coast Guard Air Field (Elizabeth City, NC) setDate = 2011-08-31 07:00:00 lethal conditions = false favorable hours = 18 LESD = 2011-08-20 KECG Advisory: do not spray today Growing degree days (base 56 F) since LESD = 511.4 Growing degree days (base 56 F) since May 1 = 2988.8 Records count: 247 out of 337 Most recent db ob to 8am EDT: 2011-09-14 06:54:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR KDPL Duplin County Airport (Kenansville, NC) setDate = 2011-09-06 07:00:00 lethal conditions = false favorable hours = 50 LESD = 2011-08-31 KDPL Advisory: spray today Growing degree days (base 56 F) since LESD = 223.8 Growing degree days (base 56 F) since May 1 = 2661.6 Records count: 175 out of 193 Most recent db ob to 8am EDT: 2011-09-14 06:55:00  -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR KEYF Brown Field (Elizabethtown, NC) no report -------------------  September 14, 2011 PEANUT LEAF SPOT ADVISORY FOR KMEB Laurinburg-Maxton Airport (Maxton, NC) setDate = 2011-08-10 18:52:00 lethal conditions = false favorable hours = 22 LESD = 2011-07-18 KMEB Advisory: do not spray today Growing degree days (base 56 F) since LESD = 1411.2 Growing degree days (base 56 F) since May 1 = 3061.9 Records count: 818 out of 829 Most recent db ob to 8am EDT: 2011-09-14 06:52:00  -------------------  These peanut crop disease advisories are being calculated and disseminated in collaboration with the NC State Department of Plant Pathology and with support from the North Carolina Agricultural Research Service.