Nutrient Management Research Database

General Information

Application of Precision Farming to Potato Production in Québec

http://ucanr.edu/sites/nm/files/76650.pdf

Crop: Potato

Soil Type: Valere sandy loam, Sante-Croix sandy clay loam, Neubois loam, Le Bras loam

Country: Canada

Year: 1998

R.R. Simard, M.C. Nolin and A.N. Cambouris

While potato fields are often fertilized at a uniform rate across a given field, not accounting for the substantional variability often present.
Variable rate (VR) fertilization allows for the incorporation of soil nutrient variaiblity by integrating GPS data with information from yield monitors and grain combines. This results in potential porfit increases by ensuring maximum yield when soil nutrient levels are below sufficient levels and limiting excess fertilzier applications when nutrient levels are sufficient.
This study investigated what economic and agronomic improvements could be obtained by utilizing a variable rate fertilization plan.
Based on initial soil test results, variable rates of phosphorus (P) and potassium (K) fertilization. The P rates were between 130 and 205 lbs P2O5/ac, while the K rates were between 140-210 lbs K2O/ac

The VR application resulted in savings of $11/ac without reducing yields, which averaged 15 tons/ac for both VR and constant rate (CR) applications in year one. In year two, VR marketable yield was 1.5 tons greater than in CR fields.
After VR application, field nutrient levels were less variable.
Potassium was the yield limiting nutrient in the VR fields.
The results of this study show that VR fertilization can be an effective means of cost reduction in potato cropping systems.