C. Karemangingo1, R. Tremblay2, N. Williams3, G. Chiasson4 and D. Savoie5
Partner: Horticulture New Brunswick
Abstract: This project assessed strawberry production practices and their effects on soils, water quality, and plant nutrient status. Current practices were generated from a questionnaire filled out by farmers while detailed information on soils and plant nutrient contents were obtained from 36 strawberry fields across the province. Risks to water quality were monitored from the drainage water samples collected from three fields from mid-August to early December 2003 and tested for nitrates and other dissolved ions. Most farmers have been applying fertilizers in the same amounts every year without soil testing. Farmers reported strawberry yields varying from below 1000 to 15000 lb/a. Strawberries are mostly grown on loamy sand to sandy loam soils with the pH varying from 4.6 to 7.2, the organic matter content from 1.5 to 7.4%, and the CEC from 4.6 to 26.8 meq / 100g soil. Phosphorus levels varied from 46 to more than 1000 ppm P, potassium from 51 to 551 ppm K, calcium from 360 to 3938 ppm Ca, and magnesium from 14 to 386 ppm. A significant number of strawberry fields (25%) were phosphorus-saturated (the third percentile value was 21.5% P saturation). Leaf N, P, K, Ca, Mg, and B contents in mid-September were = the optimum ranges at bloom stage (mid-June) while the other micronutrients were the optimum ranges. Based on the principal component analysis performed on leaf nutrient contents, calcium explained the most variability within strawberry fields. No significant correlation between any leaf nutrient and soil nutrient was established. Furthermore, the canonical correlation analysis relating the soil quality (all measured parameters) to all the leaf nutrient levels showed that soil fertility status only explained 30% plant nutritional status. As a result, strawberry fertilization is not the only key factor that requires improvement for the increase of strawberry field productivity. Drainage water contained nitrates levels above acceptable limits (10 mg NO3-N L-1) four times out of nine times. Phosphate ions varied from 0.01 to 0.08 mg L-1. Consequently, current strawberry fertilization practices may result in increased risks to water pollution. The results of this study tended to confirm the needs for better nutrient management in strawberry production.
1 NB Department of Agriculture, Fisheries and Aquaculture, Land Development Branch, PO Box 6000, Fredericton, NB, E3B 5H1
2 NB Department of Agriculture, Fisheries and Aquaculture, Agriculture Development Branch, PO Box 6000, Fredericton, NB, E3B 5H1
3 NB Department of Agriculture, Fisheries and Aquaculture, Land Development Branch, 26 Acadie Street, Bouctouche, NB, E4S 2T2
4 NB Department of Agriculture, Fisheries and Aquaculture, Agriculture Development Branch, 1425 King Avenue, Bathurst, NB, E2A 1S7
5 NB Department of Agriculture, Fisheries and Aquaculture, Agriculture Development Branch, PO Box 5001, Grand Falls, NB, E3Z 1G1