Embed Size (px)
Citation preview
IMPACTS OF LOW WATER POTENTIAL ON SOIL SALINITY AND ITS EFFECTS ON CRANBERRY DEVELOPMENT
Marie-Élise Samson J. FORTIN, J. CARON, S. PÉPIN
NACREWQuébec 2013
Introduction
Agriculture consumes each year 70% of water resources (Burton, 2010)
Worldwide, 1/3 of irrigated areas presents salinity issues (Bohn and al., 2001)
A good irrigation management is essential in cranberry production to maintain water resources, avoid salinity
problems and ensure good economic returns.
Introduction
Hoffman and al. (1990)
• In cranberry production, irrigation thresholds were suggested :
-4 kPa to -6,5 kPa (Bonin, 2008)
• Represents a decrease in soil water content
• Affects the movement of mineral fertilizers applied during plant growth
Deficit irrigation could cause salinity problems in the root layer and lead to osmotic stress in cranberry plants
Objective
Evaluate the effects of different irrigation regimes on the ions profile in a sandy matrix and their impacts on plant
development
Determine a soil electrical conductivity threshold in cranberry production
Material and methods
2 matric potential thresholds -5.5 kPa (moist treatment) -8.5 kPa (dry treatment)
A control and three salinity levels obtained with KCl S1 = 125Kg/ha K2O in form of K2SO4 S2 = 125 Kg / ha of K2O in form of KCl S3 = 250 Kg / ha of K2O in form of KCl S4 = 375 Kg / ha of K2O in form of KCl
EXPERIMENTS SUMMER 2012 :
Material and methods
• Matric potential (Tensiometers)• Water content (TDR, 5TE and EC5)• Electrical conductivity (Lysimeters, TDR and 5TE)• Ions concentrations (Lysimeters)• Photosynthesis (Li-Cor 6 400)• Pressure-Volume curves (Pressure chamber)• Abortion rates, growth and yield measurements
MEASUREMENTS :
Results
EC (dS/m) obtained weekly with lysimeters
20-04-
2012
26-04-
2012
03-05-
2012
10-05-
2012
17-05-
2012
24-05-
2012
31-05-
2012
7-06-2012
14-06-
2012
21-06-
2012
28-06-
2012
05-07-
2012
12-07-
2012
19-07-
2012
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
375 Kg/ha K2O250 Kg/ha K2O125 Kg/ha K2OControl
Date
EC
(dS/m
)
Results
Dry Con-trol
Dry 125Kg/
ha
Dry 250Kg/
ha
Dry 375Kg/
ha
Moist Control
Moist 125Kg/
ha
Moist 250Kg/
ha
Moist 375Kg/
ha
0
1
2
3
4
5
6
7
8
9
10
June 2012July 2012
Treatments
Phot
osyn
thes
is (µ
mol
CO
2 m
-2s-
1)
PHOTOSYNTHESIS MEASUREMENTS
Results
ORIGINAL OSMOTIC PRESSURE
Dry Con-trol
Dry 125Kg/ha
Dry 250 Kg/
ha
Dry 375Kg/ha
Moist Control
Moist 125
Kg/ha
Moist 250Kg/ha
Moist 375
Kg/ha
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
Treatment
Orig
inal
osm
otic
pres
sure
Ladiges (1975)
Results
YIELD AND GROWTH MEASUREMENTS
The different treatments showed no significant effects on…
• Abortion rate• Growth measurements • Yield • Fruit size• Number of seeds in each fruit
Discussion
Bieler Erable Nadeau Ncan
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
Prod
CE
10/04/2012 23/07/20120.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
Control
125Kg/ha K2O
250 Kg/ha K2O
375 Kg/ha K2O
Date
EC (d
S/m
)
Prod A Prod B Prod C Prod D
Water extraction (1:1) EC (dS/m) in the greenhouse at the beginning and at the
end of the experiment
Water extraction (1:1) EC (dS/m) obtained from four different fields during summers
2010 and 2011
EC
(d
S/m
)
Conclusion
We obtained salinity levels encountered in the fields Conditions were not stressful for plants
A salinity inferior to 1 dS/m is not a limiting factor for cranberry production
Further experiments (2013-2014) should help us find a
salinity threshold in cranberry production. The effects of subsurface irrigation will also be investigated.
Thank you!
Bohn, H. L., McNeal, B. L., and O'Connor, G. A. 2001. "Soil chemistry." 3e /Ed. Wiley. New York. xi, 307 p.
Burton, M. 2010. "Irrigation management : principles and practices." CABI North American Office. Cambridge, MA. x, 375 p.
Hoffman, G. J., Howell, T. A., and Solomon, K. H. é. 1990. "Management of farm irrigation systems." American Society of Agricultural Engineers. St-Joseph,MI. 1015 p.
Ladiges, P. Y. 1975. Some aspects of tissue water relations in three populations of eucalyptus viminalis labill. New Phytologist. 75: 53-62.
Minville, S. 2007. "État de l'écosystème aquatique du bassin versant de la rivière Bécancour : faits saillants 2004-2006, Québec, ministère du Développement durable, de l'Environnement et des Parcs, Direction du suivi de l'état de l'environnement, ISBN 978-2-550-51516-6 (PDF)." 15p.
