Irrigation of Soybean [Glycine max (L.) Merril] in a semi-arid - - PowerPoint PPT Presentation
Effect of Continuous Deficit Irrigation of Soybean [Glycine max (L.) Merril] in a semi-arid environment of Argentina Salvador Prieto Angueira 1,2 , Daniel R. Prieto Garra1 y Gabriel A. Angella 1,2 1 INTA EEA Santiago del Estero. 2 National
Salvador Prieto Angueira1,2, Daniel R. Prieto Garra1 y Gabriel A. Angella1,2
1INTA EEA Santiago del Estero. 2 National University of Santiago
del Estero, Faculty of Agronomy and Agribusiness
What is happening in the world? Water scarcity and more population
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Less available water and more food demand
What is happening in the world? Water scarcity and more population World Climate Change
www.ceres.org
Less available water and more food demand
I- Increase of temperature Could increase the vapor water demand of the atmosphere II- Increase in extreme events, for example: DROUGHT
Allen et al. 2006 y 2007
Irrigation strategies like continuous deficit irrigation (CDI) would achieves this challenge In SOYBEAN, the major economical crop in Argentina, results are contradictories and we don´t have antecedents in Argentina
Evaluate the effect of different strategies of CDI during the cycle of soybean
Irrigation scheme in which the plants are exposed to a certain level
significant decreases in performance.
Experimental Station “Francisco Cantos”
Month Precipitation (mm)
50 100 150 200 J A S O N D J F M A M J
Month Water balance (mm)
100 200 300 J A S O N D J F M A M J
Month Temperature (°C)
10 20 30 40
Tmax Tmin
J A S O N D J F M A M J
Climate: Semi-arid monsoon type
Month
Reference evapotranspiration (mm)
50 100 150 200 J A S O N D J F M A M J
Soil: Aridic haplustoll with no drainage problem. Texture is silty loam throughout the profile. Total available water is 180 mm.m-1 in the first 3 meters profile.
Irrigation depth (mm) = ETc – Pef. = (ETo×kc)-Pef Irrigation intervals: 10 to 15 days.
100% ETc 75% ETc 50% ETc 25% ETc Rainfed
Variety: DM 8002 (MG VIII – GH determinate) Optimal sowing date (SD1) 12/22/2011 Late sowing date (SD2) 25/01/2012
Month Water balance (mm)
100 200 300 J A S O N D J F M A M J
SD1 SD2
Month
Reference evapotranspiration (mm)
50 100 150 200 J A S O N D J F M A M J
SD1 SD2
method ETa (mm) = ∆S+Peff where: ∆S is the change of soil water storage considering a depth of 2 meters (gravimetric procedure), and Peff is the effective precipitation (Dardanelli et al., 1992)
20 40 60 80 100 120 140 01/25/2012 12/22/2011 SD2 SD1 Days after sowing
S-R1 R1-R5 R1-R5 R5-R7 R7-R8
SD2 cycle duration decrees 20% Weather condition during SD2 PVD 8% less Radiation 10% less ETo 8% less
1 2 3 4 5 6 SD1 SD2
VPD (kPa) / Eto (mm.día-1)
VPD ETo
100 200 300 400 500 600 Precipitation Irrigation ETa (mm)
Sowing date a b
F F
SD1 SD2
Source p-value SD <0.0001 WR <0.0001 SD*WR ns
The yield decreased with the retarding on the sowing date as a consequence of a reduction in the grain number
100 200 300 400 500 600 700 T100% T75% T50% T25% T0% mm 100 200 300 400 500 600 700 T100% T75% T50% T25% T0% mm 100 200 300 400 500 600 700 T100% T75% T50% T25% T0% mm 100 200 300 400 500 600 700 T100% T75% T50% T25% T0% mm
Water regimenes
Source p-value SD <0.0001 WR <0.0001 SD*WR ns
SD1
(Eff. precipitation 228 mm)
a b c c c SD2
(Eff. precipitation 149mm)
a b c c c
The treatments T100 and T75% were the most ETr, being higher in T100%
Irrigation depth ETa Irrigation depth ETa 73% 47% 28% 9% 100% 73% 45% 24% 0% 100%
50 100 150 200 T100% T75% T50% T25% T0% 50 100 150 200 T100% T75% T50% T25% T0% Soil water consumed (mm)
Water regimenes Although water consumption in T75% and T50% was higher compared to T100%, the differences were only statistically significant in T25% and T0% c c b c a c c b c a
Source p-value SD ns WR <0.0001 SD*WR ns
1000 2000 3000 4000 T100% T75% T50% T25% T0% Yield (kg.ha-1)
SD1 SD2 Yield did not decrease in the treatments CDI 75% and T50% in relation with T100% Water regimenes
SD Yield (kg.ha-1) GN.m-2 GW (mg) SD <0.0001 <0.0001 ns WR 0,002 0,0027 ns SD*WR ns ns ns SD Yield (kg.ha-1) SD <0.0001 WR 0,002 SD*WR ns
1000 2000 3000 4000 T100% T75% T50% T25% T0%
a ab bc abc c a ab bc abc c
2 4 6 8 SD1 SD2 WPETa (kg.mm-1)
Sowing date a b Only difference was found in water productivity between planting dates, being higher in the FS2. This could be associated with lower average vapor pressure deficit (VPD) during the second sowing date
SD WPETa (kg.mm-1) SD 0,0014 WR 0,0912 SD*WR ns
2 4 6 8 T100% T75% T50% T25% T0% WPETa (kg.mm-1)
y = -0,01x2 + 16,1x - 1407 R² = 0,88; p<0,05
500 1000 1500 2000 2500 3000 3500 4000 200 400 600 800
Yield (kg.ha-1) Actual evapotranspiration (mm)
) ) m mm l (m
T100% T75% T50% T25% T0%
y = -0,05x2 + 32,6x - 2375 R² = 0,89; p<0,05
500 1000 1500 2000 2500 3000 3500 4000 100 200 300 400
Yield (kg.ha-1) Normalized ETa (mm.kPa-1)
) ) m mm l (m
T100% T75% T50% T25% T0%
y = -0,29x2 + 81,3x - 2356 R² = 0,89; p<0,05
500 1000 1500 2000 2500 3000 3500 4000 50 100 150 200
Yield (kg.ha-1) Normalized ETa (ETa/ETo)
) ) m) mm l (m
T100% T75% T50% T25% T0%
Water National Program Project:
Evaluation of changes in water productivity against different climate scenarios in various regions of the Southern Cone