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Jacques Gallichand Jean Caron. Vincent Pelletier vincent.pelletier.8@ulaval.ca. Effect of Soil Water Tension Threshold for Irrigation on Cranberry Yield, Yield Components and Water Productivity August 27 th 2013 NACREW Québec. 1 . Introduction.
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Jacques Gallichand Jean Caron Vincent Pelletier vincent.pelletier.8@ulaval.ca Effect of Soil Water Tension Threshold for Irrigation on Cranberry Yield, Yield Components and Water Productivity August 27th 2013 NACREW Québec
Soil Water Tension (Or Soil water Potential) 10 cm h = 40 cm SWT = 4 kPa φm = -4 kPa 40 cm 4 kPa Water Table
Objective This study was conducted to determine the optimum soil water tension for starting irrigation that would optimize water productivity without decreasing yield and yield components (Water productivity was calculated as the yield per unit depth of rainfall and irrigation)
Experimental Setup • 3 sites in Québec • 1 site in Wisconsin
Retention Curve Irrigation Thresholds Wet (5.5 kPa) Control (6.0 - 6.5 kPa) Dry (7.0 – 10.0 kPa)
Measurements • Soil water tension (Tensiometer) • Rainfall (Weather Station) • Irrigation water (Flow meter) • Yield : 2474 samples (929 cm2) • Yield components : 132 samples (929 cm2) • Water Productivity (Yield / (Rainfall+Irrigation)) • Statistical analysis to determine the best threshold
Yield • In 2011 No difference between treatment • In 2012 No difference between 5.5 to 8.5 kPa Significant reduction of 11 % in the driest treatment (10.0 kPa) Average yield: 33690 lbs/acre
Yield components • In 2011 : No significant difference • In 2012 - Significant differences : • - 21 % of marketable berries at 10.0 kPa • - 14 % of berries / upright at 8.5 kPa • - 9 % less fruit set at 8.5 kPa • - 7 % of berry weight at 8.0 kPa • No difference between 5.5 and <8.0 kPa
Water Productivity • 2011-2012 : Significantly greater in Dry treatments • Wet (5.5 kPa) : 54 – 186 % more irrigation water • Dry (7.0–10.0 kPa) : 21 – 93 % less irrigation water
Hydraulic Conductivity vs Soil Water Tension Good capillaryrise Optimum yields Water savings Energysavings Water stress affectedyields and yield components Maximum ET rate
Conclusion • In fine sand, Dry treatments, with irrigation thresholds ranging from 7.0 to 7.5 kPa, improved significantly the water productivity without decreasing yield and yield components • Current research • (2013-2015) • The capillary rise is sufficient to meet the plant needs when the water table is controlled at an optimal level
Thank You !!! CannebergesBieler Nature Canneberge Transport Gaston Nadeau Salzwedel Cranberry FermeOnésimePouliot