Tomato and Pepper Scout Training Weed Control in Tomatoes and Peppers Darren Robinson Dual+Sencor (PPI) Advantages Weaknesses Single application Residual grass and broadleaf control including EBN Can set back transplants low OM Triazine tolerant weeds escape 1
Dual injury on tomatoes Sikkema RC Sencor injury on tomatoes Sikkema RC 2
Treflan+Dual+Sencor Advantages Weaknesses Residual broadleaf control Control of triazine tolerant lambsquarters* Can set back transplants shallow planting Less residual control of EBN Untreated check Treflan (0.84 L/ac) + Dual (0.5 L/ac) + Sencor (0.4 L/ac) Robinson RC 3
Treflan injury on tomatoes Sikkema RC Yield loss caused by Treflan + Dual Magnum + Sencor (PPI) increased as transplanting depth decreased 0.5 in 1 in 2 in 4 in 0 10 20 30 40 Yield loss (% of 4 Inch Depth) Yield Sikkema, RC 4
Dual/Sencor PPI + Sencor POST Advantages Weaknesses Improvement in broadleaf control velvetleaf No control of triazine-resistant lambsquarters Reduced chance of crop injury Requires 4 or 5 applications Dual (0.7 L/ac) + Sencor (0.2 L/ac) PPI + Sencor (0.12 L/ac) * 3 POST Robinson RC 5
Weed size at time of micro-rate applications Robinson RC Comparison of herbicide programs redroot pigweed EB nightshade lamb'squarters velvetleaf Dual + Sencor; 3 Sencor Dual + Sencor Treflan + Dual + Sencor 0 20 40 60 80 100 Robinson RC 6
Summary Excellent control of broadleaf weeds Dual+Sencor PPI fb Sencor Dual+Sencor and Treflan+Sencor provide less consistent control of the spectrum of common broadleaf weeds found in SW Ontario. Common lambsquarters Bouchard and Neron, 1999 7
Common ragweed Bouchard and Neron, 1999 Velvetleaf Bouchard and Neron, 1999 8
Redroot pigweed Bouchard and Neron, 1999 Eastern black nightshade Bouchard and Neron, 1999 9
Hairy nightshade Bouchard and Neron, 1999 Maximum size of hairy nightshade for Prism control 10
Relative germination intervals Lambsquarters Common ragweed Velvetleaf Redroot pigweed Eastern black nightshade Hairy nightshade late April to late June early May to June mid-may to July Postemergence broadleaf herbicides Sencor General broadleaf control Pinnacle Triazine-tolerant weeds (lambsquarters, pigweed) Prism Hairy nightshade 11
Pinnacle Metribuzin Sikkema RC Pinnacle injury on tomatoes Robinson RC 12
Observations on Pinnacle 3.2 g/ac; applied 21 days POST-transplant Triazine-tolerant weeds Not registered as tank mix with Sencor Injury more likely If applied when temps >32 o C Frost-injured plants Varietal sensitivity (eg. N1069, H9909) Pinnacle 3.2 g/ac H9553 Robinson RC 13
Pinnacle 3.2 g/ac H9553 Robinson RC Prism injury on tomatoes Robinson RC 14
Problem grass weeds in tomatoes and peppers Large and smooth crabgrass Foxtails yellow, giant, green Fall panicum Smooth crabgrass Large crabgrass Bouchard and Neron, 1999 15
Yellow foxtail Bouchard and Neron, 1999 Giant Foxtail Green foxtail Bouchard and Neron, 1999 16
Fall panicum Green foxtail vs. Fall panicum LOOKS VERY SIMILAR TO FALL PANICUM WHEN YOUNG!!! Hairs along margins of leaf sheath in green foxtail Hairs not present in fall panicum 17
Annual Grass Control Excel Super Venture L Poast Ultra 50 60 70 80 90 100 Weed Control (% ) Yellow, giant, green foxtail Barnyardgrass, witchgrass, fall panicum ECW, 1994-1999 Control of annual grasses with Prism Sikkema RC 18
Annual grass control with Prism Smooth Crabgrass Large Crabgrass Barnyard Grass Witchgrass Fall Panicum Green Foxtail Yellow Foxtail 0 20 40 60 80 100 % weed control ECW, 1994-1999 Weed Control in Peppers Treflan annual grasses, chickweed, PW, LQ Devrinol some broadleaf suppression Dual II Magnum annual grasses, some broadleaf control (pigweed, EBN, lambsquarters) Command eastern black nightshade, annual grasses (weak on pigweed) 19
Dual (0.5 L/ac) Dual+Devrinol (0.5 L/ac + 1.8 kg/ac) O Sullivan, Simcoe Dual+Dacthal untreated (0.5 L/ac + 6.2 kg/ac) O Sullivan, Simcoe 20
Sikkema RC WSSA Website 21
Spray drift injury in vegetables 22
Robinson RC 23
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Banvel drift in tomatoes WSSA Website 25
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Some resources: Injury symptoms PPI/PRE: http://www.omafra.gov.on.ca/english/crops/facts/info_herbicide2.htm Injury symptoms POST: http://www.omafra.gov.on.ca/english/crops/facts/info_herbicide.htm Herbicide efficacy: http://www.omafra.gov.on.ca/english/crops/facts/info_broadleaf.htm This presentation: http://www.ridgetownc.com/research/documents/robinson_ipm_scouti ng_meeting_april.pdf Darren Robinson drobinso@ridgetownc.uoguelph.ca (519) 674-1604 29