1. Alternate wetting and Drying in
rice (AWD) and its adoptation
Shantappa Duttarganvi
shantud4@gmail.com
8499034130

2. Introduction
RICE IS LIFE
Cultivate more land with less water

3. Rice
India
• Area: 44mha
• Production: 104mt
• Productivity: 2001kg/ha
AP
• Area: 43.7 Lha
• Production: 140 Lt
• Productivity: 3032kg/ha

4. DES, 2009

5. Pressure to produce more food (rice) because of ever
increasing population
UN, 2004 (Wikipedia)
In 2020, the world
needs to produce
an additional 50-80 M
tons of paddy rice
= 125-200 km3 of water
But also: More people means
• more industry
• more drinking water
• more sanitation water
• more swimming pools
• more cars to wash
• more gardens to sprinkle
• more…
=> Water is getting scarce and expensive

6. Water: A Global Issue
„too little, Too much, or too dirty‟
•
•
•
•
•
1.3 billion without safe water supply
2 billion without sanitation
800 million malnourished
Thousands killed by floods
Every day reports on water related issues

7. Water Availability: 1975
Water Availability: 2025
Extreme Scarcity
<500
Scarcity
500-1,000
Stress
1,000-1,700
Adequate
1,700-4,000
Abundant
4,000-10,000
m3/person/year
Surplus
>10,000
Ocean/
Inland Water
No Data

8. 
Future is going to be even uncertain interms of rain
fall, ground water and surface water

Periodicity, intensity and distribution of rain fall is
going to change

9. Rice and water
 70% water used for irrigation globally
 Rice uses > 80% water in many countries
 3-5,000 litres to produce one kg

10. Crop water use
1kg
=
3,000- 5,000
litres water
1kg
1kg
=
3,000 – 5,000
litres water
=
1,500 - 3,000
litres water
So, we eat, wear, drink.. water…

11. Objectives of the Session
Produce more rice with less water

12. Components of water balance
in rice fields
Bouman, 2001

13. Water-saving measures
•
Puddling and Land leveling
•
Crack plowing
•
Alternate wetting and drying
•
Communal seed beds
•
Efficient use of rainfall (cropping calendar)
•
Direct wet seeding
•
Aerobic rice
•
Pressurized irrigation

14. Crack plowing
Compaction
Good puddling
……..
‘Safe’ AWD
Yield
Diversification
(non rice crops)
Aerobic
rice
Upland
Low
High
Water availability
various response options to water scarcity
Flooded
lowland

15. Before puddling
harrow to close
the cracks
Construct a
field channel
for irrigation
Irrigate up to
5 cm, maximum
Maintain bunds,
seal cracks, and
close rat holes
Make a farm
ditch for proper
drainage
Ensure good
field levelling
Ways to use water wisely

16. LAND PREPARATION
 Cracks favour rapid “by-pass flow”
 Shallow tillage to remove cracks
 Soaking prior to puddling
 Thorough puddling
 Plot to plot irrigation removes valuable
nutrients

17. Control
Cracks Ploughed
During land preparation, Bulacan, Phillipines, Cabangon and Tuong (2000)

18. PERFECT LEVELING IS ESSENTIAL
IMPROPER LEVELING LEADS TO….
•
Uneven crop growth
•
Uneven fertilizer distribution
•
Extra weed problems
BUND PREPARATION AND MAINTENANCE
• A reduction of 450 mm of total water use

19. METHODS OF WATER APPLICATION
Continuous
submergence
•Less supervision
•Less expenditure
on weed control
Intermittent
submergence
• Saves irrigation water
• Minimizes the formation of
toxic substances
• Lessen drainage problem
Continuous
saturation
• More weeds
• Water saving

20. Continuous submergence
• High water requirement
3000–5000 liters of water to
produce 1 kg of rice
• Environmental degradation
• Reduces fertilizer use efficiency
• Destruction of soil aggregates
• Anaerobic fermentation of soil
organic matter: Methane emission

21.  AWD: „intermittent irrigation‟ or „controlled irrigation‟
 Alternate flooding: Number irrigations reduced without reducing
yield
 AWD period vary based as rainfall pattern, climatic condition,
depth of water and texture
 Plant roots have access to hidden water in root zone
 Compared with the traditional continuous flooding system, AWD
can reduce water input by 15-30% without yield loss

22. Safe AWD
60
Field water depth (cm)
flowering
CF
5
2.5
0
AWD
Soil surface
-5
-10
-15
-20
0
10
20
30
transp
Early
recovery tillering
40
Late
tillering
50
60
70
PI to complete
flowering
Days after transplanting
80
90
grain
filling
100 110
Maturity

23. Using tensiometer: To measure moisture availability
of the soil for crops (expressed as soil tension)
Safe AWD when: Soil Tension at 15
cm soil depth > - 10 kPa

24. A practical indicator to irrigate under safe AWD
• Safe AWD = Irrigate when water depth ~ 15 cm
• Keep flooded 10 DAT (weeds) and at flowering
Simple key messages for farmers
Simple tool that help farmers decide when to irrigate
Farmers can experiment with threshold levels

25. Key points of AWD
• Transplant young seedlings into puddled
soil
• Install a PVC pipe with holes
• Start AWD at 10 DAT and allow the field
to dry out
• Re-flood the field to a standing water
layer of 5 cm when the groundwater is
15-20 cm below the soil surface
• Keep a standing water layer of 5 cm for 1
week at flowering
• Continue AWD cycles after flowering
until harvest
• Scope for 10, 20, 25 and 30 cm with
different genotypes and different location

29. YIELD AND WATER USE OF AWD AND CONTINUOUSLY FLOODED
CONDITIONS
Location
Treatment
Yield
(t ha-1)
Total
water
input
(mm)
Tuanlin, Huibei, China 1999
(Belder et al 2004)
Flooded
AWD
8.4
8.0
965
878
0.90
0.95
2000
Flooded
AWD
8.1
8.4
878
802
0.92
1.07
2001
Flooded
AWD
7.2
7.7
602
518
1.20
1.34
Munoz, Philippines,
(Belder et al 2004)
Year
Water
productivity
(g grain kg-1
water)
BOUMAN et al. (2006)

30. Results
-No yield difference between AWD and farmers’ practice
-Farmers achieved 16-30% savings by adopting AWD
-Increased net profit
- reduced competition of water between households and rice farming.
Irrigation water used (mm)
AWD
Yield (t/ha)
AWD

31. AWD Promotes higher zinc availability
In the soils :
soil Zn (mg/kg)
AWD vs. CF:
•higher redox (i.e.
more oxidized)
•higher Zn
availability

32. Better root anchorage to reduce lodging

33. 4. AWD reduces methane emissions!
N2O & CH4
g CO2 eq./m2/season
Continuous
flooding (CF)
1,440
AWD 1
AWD 2
AWD 3
48 h
Field Water level
48 h
500
390-540
Flooding
for 1 week
Time
390
Hosen et al. unpubl.

34. Precautions
•
•
•
•
Sandy, salt affected soil
Levelled land
Weed problem
Flowering

35. Perceived benefits of AWD by farmers
 Reduced total pumping cost and labor
Better rooting system: lodging have been reduced
Mechanized harvesting
Soil sterilization: Rice plants have less pest population
Grain quality will improve
Knowing the concept of AWD, they do not worry even if the
rice field do not have water

36. Thank u