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Burley Tobacco Update Fertilization and Pesticides. Dr. Bob Pearce Extension Tobacco Specialist. 2007 ANR Agent Update Elizabethtown, Kentucky November, 27 2007. Outline. Nitrogen fertilizer issues Source concerns Rate recommendations Possible boron deficiency Pesticide residues
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Burley Tobacco Update Fertilization and Pesticides Dr. Bob Pearce Extension Tobacco Specialist 2007 ANR Agent Update Elizabethtown, Kentucky November, 27 2007
Outline Nitrogen fertilizer issues Source concerns Rate recommendations Possible boron deficiency Pesticide residues Endosulfan MH Variety Update
Nitrogen Fertilizer Issues • Economics • Leaf prices steady (at best) • N fertilizer prices up • Price tied to natural gas • Transportation costs up • Nitrosamine concerns • Tobacco companies want less N applied • Quality concerns • Too little: thin body, poor yield • Too much: delayed maturity, fat stems • Potential regulations on ammonium nitrate
Price Per Unit of Nitrogen for Selected Fertilizer Materials
Alternative N Sources • Dolomitic – Ammonium Nitrate (27% N) • Ammonium nitrate mixed with lime • 78% ammonium nitrate • Theoretically similar to ammonium nitrate • Can impregnate some chemicals ? • Relatively high cost? • Availability (Bagged) • Limited practical experience • Initial acceptance • Poor
Alternative N Sources • Calcium Nitrate (15.5% N) • Sodium Nitrate (16% N) • Sodium-Potassium Nitrate (15% N) • Immediate uptake (good for sidedress) • Good for low pH soils • Erratic availability • High cost (>$1.20 /lb.) • Low analysis – high transport cost
Alternative N Sources • UAN • Cost competitive • Easy to apply • Availability ?
Nitamin Fertilizer Test-2006Fayette County – Spindeltop Farm
Nitrogen Fertilizer TestFayette County – Spindeltop Farm Weighted Avg. price for crop
Multi-State Burley Tobacco N test Six location/years (TN, VA, and KY)
Multi-State Burley Tobacco N test Six location/years (TN, VA, and KY)
Boron Fertility TestBernie Cave Farm 2007 Planted 6/16/07 Rated 7/26/07 ppm B in plant Check = 13.0 0.25 TW = 15.3 0.50 TW = 18.3
Pesticide Concerns • Illegal pesticides • Could void contract • Indiscriminant use of labeled pesticides • Endosulfan (Golden Leaf) • Do not use at or after topping • MH • Others • Pounce • Prowl
Endosulfan Residues in Cured Burley:University of Tennessee 2005 * Harvested 20 days after last application ** Harvested 5 days after application
Start right • Admire 2F • Admire Pro • 0.5 fl oz/1000 • Generics • Alias • Couraze • Nuprid • Widow • Platinum • 0.5 fl oz/1000 1 fl oz/ 1000
Budworms • Threshold • 5 or more per 50 plants • 3 weeks after trans planting until 1 week before harvest
Hornworms • Threshold • 5 or more hornworms per 50 plants • 3 weeks after trans planting until harvest • Do not count if white cocoons.
Combination Sucker Control Recommendation • Reduce MH rate and add a local systemic • 1.5 gal MH + 0.5 gal Butralin, Flupro or Prime+ • Use Coarse nozzles • TG-5 / CE-5 or equivalent at 4-4.5 mph • TG-3 / CE-3 or equivalent at 2.5-3 mph
Range of MH Residues in Kentucky for 1997 - 2004 Low < 41, Medium = 41-80, High = 81-120, Very High = 120 - 200, Extremely High >200 ppm
Comparison of Sucker Control Treatments at Two Weeks after ApplicationUK Spindletop Farm (MH= Royal MH-30, F=Flupro, B=Butralin,) in (gal) O=Off-Shoot-T in (%), UTC=untreated check, fb=followed by at 7 days. *=Sprayer malfunctioned
The Effects of Sucker Treatment on Sucker Number per Plant UK Spindletop Farm (MH= Royal MH-30, F=Flupro, B=Butralin,) in (gal) O=Off-Shoot-T in (%), UTC=untreated checkfb=followed by at 7 days. *=Sprayer malfunctioned
The Effects of Sucker Treatment on Sucker Weight UK Spindletop Farm (MH= Royal MH-30, F=Flupro, B=Butralin,) in (gal) O=Off-Shoot-T in (%), UTC=untreated check,fb=followed by at 7 days. *=Sprayer malfunctioned
MH Free TrialsComparison of Sucker Control TreatmentsUK Coldstream Farm (MH= Royal MH-30, F=Flupro, B=Butralin,) in (gal) O=Off-Shoot-T in (%), UTC=untreated check(-) followed by at 5 days.
Effects of Nozzle Size on Sucker Control* *Treatments consisted of 4% Off-shoot T at elongated bud followed by a combination of Off-shoot T at 4 % plus Butralin at 1 gal /a.
Effects of Nozzle Size on Sucker Control All Nozzles were TG full cone nozzles
Getting Closer to MH free but …. • Will probably require multiple trips • Fatty alcohol prior to topping • One or two trips after topping • Fatty alcohol availability and price ??? • Still expect some escapes • Usually top one or two nodes • Some hand removal may be necessary • Relatively low sucker pressure in 2007?
Variety Update • KT 206 • High black shank resistance (race 0) • Blue mold tolerance (similar to TN 90) • High Yield (3300 - 3400) • Big tobacco/large stalk • N 7371 • Moderate black shank resistance • Long narrow leaves • High yield (3200) • Dark color