Presentation on theme: "Scouting and Fungicides Jeff Miller. Scouting for Disease Can be used to determine when to apply fungicides – When needed instead of “just because” Very."— Presentation transcript:
Scouting for Disease Can be used to determine when to apply fungicides – When needed instead of “just because” Very useful for late blight Not applicable for some diseases – Rhizoctonia – Pink rot – White mold – Early blight
Principles of Scouting Pages 142-144 1.Examine every field 2.Take a directed sample (altered from book) 3.Sample across the entire field 4.“Take” enough samples 5.Keep good records
What is a Fungicide? Any substance or mixtures of substances intended for preventing, destroying, repelling, or mitigating fungal pests. Definition adapted from the Environmental Protection Agency www.epa.gov/pesticides/
Soil-Applied Fungicides Incorporated during row-markout – Broadcast – incorporated – Banded in the row In-furrow at planting – Low volume (~5 gpa) – Banded over the seed piece
Foliar Applications 1.Aerial – Airplane – Helicopter 2.Chemigation – Injection in water 3.Ground
Foliar Application Comparisons ChemigationAerial Cost/acre$1.50-2.50$7.00-9.00 Spray Volume~ 4500 gallons (0.10-0.15”)5-10 gallons Labor (grower)HighVery low Residue in canopyLow*High* Estimated usage40-45%45-50% Canopy residue is lower with chemigation, but distribution is more uniform.
Post-Harvest Fungicides After harvest, prior to placement in storage Few fungicides labeled – Thiabendazole – Phosphorous acid – “Disinfectants” During storage Applied as a volatilized product through plenums – “Disinfectants” – Phosphorous acid