This document discusses irrigation management for sustainable crop production. It covers several key topics: - Irrigation scheduling approaches like climatological, pan evaporation, growth stage basis, and soil moisture basis to optimize water use. - Deficit irrigation, which involves deliberate under-irrigation, can boost water productivity while still achieving acceptable yields by applying water only during sensitive growth stages. - Integrated strategies for reducing water demand like shifting sowing times, selecting drought-tolerant varieties, and proper scheduling. - Increasing water supply through surface storage, recharge, and optimizing soil moisture retention with organic matter or fertilizer.

1. Irrigation Management for Sustainable Crop Production
Engr. Dr. Md. Hossain Ali
CSO & Head
Agricultural Engineering Division
BINA
Cell: 01818- 486534
Email: mha_bina@yahoo.com,
hossain.ali.bina@gmail.com
URL: http://www.mhali.com

2. Irrigation & Crop
Water Management
Ground Water
Studies
Agro-Climatic
Studies
Water Management for
saline area
Water Management for
drought area
Research Areas of Agril. Engg. Div.

3. Deliberation on:
 Why irrigation management ?
 Irrigation management issues
 Approaches or methods of irrigation scheduling
 Water Management strategies
 Some research findings
 Discussion
3

4. Driving Forces in Irrigation management:
• Water availability (both surface and
groundwater)
• Economics
• Environmental factors
• Climate change issue
4

5. Agricultural Cropping Patterns in relation to Water
availability
Jan Feb Mar Apr M Jun Jul Aug Sep Oct Nov D
Wheat-pulses
Rice -1
Rice -2
Rice -3
0
10
20
30
40
50
60
Jan Feb Mar Ap May Jn Jly Aug Sep Oct Nov Dec
Rainfall
(cm)
5

6. Fig.3. Cost and revenue curve in the land-limiting condition
0
10000
20000
30000
40000
50000
0 5 10 15 20 25 30
Applied water (cm)
Cost
and
Revenue
per
ha
(Tk) Cost
Revenue

7. Fig.2. Cost and revenue curve in the water-limiting condition
(After Ali, 2008)
0
10000
20000
30000
40000
50000
T9 (4 nos) T6 (3 nos) T7 (2 nos) T10 (1 nos)
Strategy (Irrigation frequency)
Cost
&
revenue
per
1000
m
3
water
(Tk)
Cost
Revenue

8. Alarming situation of groundwater !!
Due to continuous pumping of groundwater, the
groundwater level is declining in most parts of the
country.
8

9. 9

10. Year
-1
4
-1
2
-1
0
-8
-6
-4
-2
0
2
4
85 87 89 91 93 95 97 99 1 3 5
Durgapur
Well-RJ68 Well-RJ1
2
Well-RJ30 Rainfall
Suc. Lift
10

11. Year
-30
-25
-20
-15
-10
-5
0
5
10
85 87 89 91 93 95 97 99 1 3 5
Mohanpur
Well-RJ23 Well-RJ28
Rainfall Suc. Lift
11

12. Year
-1
2
-1
0
-8
-6
-4
-2
0
2
4
85 87 89 91 93 95 97 99 1 3 5
Puthia
Well-RJ31 Well-RJ69
Well-RJ70 Well-RJ09
Well-RJ27 Rainfall
Suc. Lift
12

13. y = 0.2849x + 5.4208
R² = 0.414
0
4
8
12
16
0 5 10 15 20
Depth
to
WT
(m)
Relative year
Mymensingh Sadar
Well-24
y = 0.5383x + 3.6879
R² = 0.8023
0
4
8
12
16
0 5 10 15 20
Depth
to
WT
(m)
Relative year
Mymensingh Sadar Well-52
y = 0.0069x + 11.479
R² = 0.0009
0
4
8
12
16
0 5 10 15 20
Trishal Well-25
y = 0.3062x + 9.5868
R² = 0.3699
0
4
8
12
16
20
0 5 10 15 20
Trishal Well-56
y = -0.0157x + 4.0943
R² = 0.0313
0
4
8
0 5 10 15 20
Gouripur
Well-32
y = 0.097x + 4.0635
R² = 0.7634
0
4
8
0 5 10 15 20
Gouripur Well-46
13

14. Adverse situation ….
In our contest, we will be confined with the following
adverse conditions:
- Drought
- Flood
- Salinity
14

15. Climate Change issue
 Climate change is any long-term significant change in the
“average weather” that a given region experiences.
 Climate change involves changes in the variability or average
state of the atmosphere over durations (ranging from
decades to millions of years).
15

16. Impacts/Effects of climate change
Climate change can:
 increase or decrease rainfall,
influence agricultural crop yields,
affect human health,
cause changes to forests and other ecosystems,
or even impact our energy supply.
16

17. Effects of Climate Change …..
- Climate change will lead to more periods of high temperature
and periods of heavy rain.
- Unseasonal or extreme weather will have an increasing
impact on crop production
- There are already examples of what to expect
17

18. Climate Change issue
 Climate change is any long-term significant change in the
“average weather” that a given region experiences.
 Climate change involves changes in the variability or average
state of the atmosphere over durations (ranging from
decades to millions of years).
18

19. Impacts/Effects of climate change
 Climate change can increase or decrease rainfall, influence
agricultural crop yields, affect human health, cause changes to
forests and other ecosystems, or even impact our energy supply.
19

20. Pattern of long-term Climatic parameters in Bangladesh
 Increasing or decreasing trend (variable with space and time)
20

21. y = 11.79 + 0.003x
0
2
4
6
8
10
12
14
16
0 5 10 15 20 25 30 35
Temp.,
0C
Relative year
Min. Temp. in Jan., Mym.
y = 25.23 - 0.052x
0
5
10
15
20
25
30
0 5 10 15 20 25 30 35
Temp.,
0C
Relative year
Max. Temp. in Jan., Mym.
21

22. y = 1586.3 - 3.2146x
0
500
1000
1500
2000
2500
1
3
5
7
9
11
13
15
17
19
21
23
25
27
29
31
33
Rainfall
(mm)
Relative Year (from 1976)
Trend of rainfall at Rajshahi
22

23. Climate Change and Water Resources
Impact of climate change on water resources (WR):
 Varies directly with rainfall
Impact may be on:
 Rainfall
 River-flow
 Availability of GW
 Demand of water
23

24. Impact on Crop-water demand:
Simulation model study shows that:
If the maximum temperature increases by 10 %
(while other weather parameters remain constant), the crop
evapo-transpiration will be increased by 7.3 %.
24

25. Factors affecting crop water requirement
• Weather factor
• Crop factor
25

26. Crop factors influencing crop water
requirement
• type of crop
• cultivar / species
• growing stage
• leaf area
• leaf type, stomatal behavior
• root length, root density
26

27. Fig.3. Typical pattern of ET demand during the growth
period of cereal crop
27
0
1
2
3
4
5
6
0 20 40 60 80 100
% Growth period
ET
(mm/day)

28. Distinguishing characteristics of crop water
requirement and irrigation water requirement
28
Crop water requirement Irrigation water requirement
1. It is a function of weather and crop 1. It involves additional factors other than the
weather and crop
2. Normally it is less than the irrigation
water requirement
2. Normally it is higher than the crop water
requirement
3. It is not a function of soil and
irrigation method
3. It depends on soil type and irrigation
method
4. It does not depend on rainfall (but
on temperature and humidity)
4. Irrigation water requirement decreases if
there is any rainfall
5. It is not a function of depth to water-
table or saturated layer.
5. It decreases with the contribution of
upward flow from the water-table or
saturated layer.

29. Strategy for achieving sustainable crop production
Strategic options for achieving sustainable crop
production include:
• Alternate cropping pattern (cultivating low water-
demand crop),
• Water saving irrigation scheduling,
• Developing stress/drought tolerant crop varieties,
etc.

30. Goal /Strategy of Irrigation
The possible irrigation goals may be:
• Maximizing yield per unit of land
• Maximizing yield per unit of water (i.e.
maximizing water productivity)
• Maximizing yield per unit of energy
• Profit maximizing
30

31. Irrigation scheduling approaches
• Climatological approach
• Pan evaporation
• Crop growth stage basis
• Soil moisture basis
• Deficit irrigation concept
• Soil-water potential
31

32. Irri. scheduling approaches ………
• Leaf water potential
• Stress-day index
• Irrigation calendar
• Check-book or soil-moisture balance
approach
• Modelling approach
• Real-time irrigation scheduling
32

33. Fig. 4. Schematic illustration of a real-time irrigation
scheduling system
33
Data
logger
Real
time
soil
moisture
PC containing algorithm
for scheduling irrigation
Daily weather data
or weather forecast

34. Deficit irrigation
Background
• All growth stages of crops are not identical in their
susceptibility to any moisture deficit.
• The sensitivity of various growth stages to water stress
have been variable, depending upon variety, plant types
(tall or dwarf), and maturity period.
• Generally water stress reduces biological yield, but it does
not always decreases economic yield; in fact in some
cases it may increase it.
34

35. Deficit irrigation …..
Background …
• In water-scarce areas, water (not land) is the
primary limiting factor to improve agricultural
production.
• Accordingly, maximizing yield per unit of water,
and not yield per unit of land, is a more viable
objective for on-farm water management.
• Scarce water now used for full irrigation may be
revised for improved water productivity.
35

36. Concept and definition of Deficit Irrigation
• By definition, deficit irrigation is the deliberate
and systematic under-irrigation of a crop
(Marshal, 1990).
• Simply speaking, deficit irrigation means less
application of water than a plant ‘has the
potential to use’ or ‘would normally use’.
36

37. Deficit irrigation ……
The potential benefits of deficit irrigation may
be achieved from the following factors:
• Increased irrigation efficiency,
• Reduced costs of irrigation, and
• The opportunity costs of water
37

38. Modes of deficit irrigation
• Increasing interval between irrigations
• Omitting irrigation during certain growth
stages
• Irrigation can be omitted during the stage or
stages which are less sensitive to moisture
deficit.
• Providing a part of evapotranspiration (ET)
demand (i.e. reducing irrigation depth)
38

39. Modes of deficit irrigation ……
• Wetting partial root zone
• Wetting alternate furrows
• Allowing root zone soil-water depletion to a
particular level
• Allowing root zone soil-water depletion to
reach a particular level of leaf water potential.
• Any combination of the above.
39

40. Fig.10. Pattern and mathematical relation of (a) IR vs WP, IWP and
(b) ET vs WP
WP = -0.1047x2 + 1.9705x + 122.16
R2 = 0.314
IWP = 0.5066x2 - 30.084x + 571.99
R2 = 0.9431
0
100
200
300
400
500
0 10 20 30 40
Irrigation water (cm)
WP,
IWP
(t/ha/cm)
WP
IWP
y = -2.2325x + 183.51
R2
= 0.4686
0
50
100
150
200
0 10 20 30 40 50 60
ET (cm)
WP
(kg/ha/cm)

41. Fig. 5. Relationship of wheat yield and ET, and WP, irrigation water
productivity (IWP) & irrigation water (After Ali, 2008)
41
0
100
200
300
400
500
0 10 20 30 40
Irrigation water (cm)
WP,
IWP
(kg/ha/cm)
WP
IWP
0
1
2
3
4
5
10 20 30 40 50
ET (cm)
Yield
(t/ha)

42. Yield and water productivity relationship under
deficit irrigation
• Deficit irrigation can effectively boost water
productivity.
• But the higher productivity indices in themselves
are of little interest if they are not associated with
higher (or acceptable) yields.
42

43. Principles or Strategies for mitigating water
shortage
 Increasing availability of water (supply management)
 Reducing water demand (demand management)
43

44. Integrated approach for Reducing water demand
Drought escape: agronomic manipulation
 Shifting time of sowing/transplanting
 From “Boro – T.Aman ” to “Late T.Aus – Late T.Aman”
44

45. Reducing water demand:
Proper irrigation scheduling
For rice: “Alternate drying and wetting” approach
For cereals: Omitting irrigation after soft-dough stage
Appropriate crop/variety selection
 Cultivating low water-demanding crop (e.g. Wheat, instead of
Rice, where feasible; wheat requires 1/4th to 1/5th water)
 Selection of drought tolerant crop variety (e.g. Binadhan-8)
45

46. Reducing water demand…
Dry seeded rice / dry-land culture
Have limitations (weed problem, only feasible in upland & medium
land, not appropriate for clayey soil)
Seed priming
Soaking seeds in water for a specific period (12 – 14 hrs), then
surface dried and then sown.
(crops like wheat, maize, lentil, chickpea, etc.; for rainfed as well
as irrigated crops grown on normal soils)
46

47. Reducing water demand…
Increasing seedling age (up to 55-60 days for Boro; 60-65 days for
Aman)
The older seedling (55 to 65 days) could reduce crop duration
up to 15 days.
Reducing water loss (Ev., Tr.) by adding organic matter (O.M.)
O.M. prevents water loss (slowly release the soil-water) thus
mitigate drought effect / reduce water demand
47

48. Reducing water demand…
Proper irrigation scheduling / deficit irrigation
• Reducing irrigation frequency/number (giving irrigation only at
sensitive growth
stages)
• Optimal sequencing of irrigation (or deficit) (e.g., irrigation +
deficit + irrigation + deficit….)
48

49. Supply management
Increasing availability of water by:
- Surface water storage
- Natural canal
- Farm pond
- Community based canal
Artificial recharge (increasing groundwater storage)
49

50. Supply management…
Soil-moisture storage
- optimum fertilizer input improve the extension of the
root system, thus increase plant extractable water
- by organic/crop residue application
50

51. Supply management…
Soil-moisture storage
- optimum fertilizer input improve the extension of the
root system, thus increase plant extractable water
- by organic/crop residue application
51

52. Available technologies for sustainable & profitable
crop cultivation with limited irrigation water
Technology developed by Agricultural Engineering Division, BINA:
52

53. Irrigation scheduling for the mustard varieties
Variety: Safal and Agrani
1st irrigation 2st irrigation
Mymensingh 35 – 40 DAS -
Ishurdi 25 – 30 DAS 65 – 70 DAS
Jamalpur 25 – 30 DAS 65 – 70 DAS
DAS = Days after sowing
53

54. Water saving in rice cultivation
 Alternate ‘flooding’ and ‘drying’ for 5-7 days after
disappearance of ponded water’ save about 40% of irrigation
water with insignificant yield loss.
The practice can reduce continuous decline of water table.
Tested varieties: Binadhan-6, Binadhan-8, Binadhan-10
54

55. Supplemental irrigation for Binasail rice
Binasail is a low Input T. aman rice variety that does not require
any supplemental irrigation at Mymensingh and Jamalpur areas.
However, depending on natural precipitation, one irrigation may
be given to grow this variety at Rangpur and Ishurdi areas.
55

56. Irrigation management for Wheat
(for Ishurdi)
Tested variety: Shatabdi
Irrigation option
/ availability
Time of
1st irrigation
Time of
2nd irrigation
Time of
3rd irrigation
1 irrigation 20 – 22 DAS - -
2 Irrigation 20 – 22 DAS 60 – 65 DAS -
3 irrigation 20 – 22 DAS 40 – 45 DAS 60 – 65 DAS
Yield obtained
(av. of 3 yrs)
3.0 t/ha 3.39 t/ha 3.7 t/ha
* Post-sowing irrigation was applied for all cases 56

57. New cropping pattern for Barind area through soil
water conservation
Season T.aman Rabi Kharif-I
Crop
option
Binadhan-
7
Chickpea
(Binasola)/
mustard
Mungbean
(Binamoog-
5,6,7,8)/sesame
(Binatil-1/2)
Irrigation
water req.
Rainfed No irrigation /
One irrigation
Pre-sowing
irrigation
Yield
obtained
4.5 t/ha 1.6 – 1.8 t/ha 1.19 t/ha,
1.07 t/ha
57

58. Water-logging tolerance limit of sugarcane
 The sugarcane variety ISD-21 is tolerant to waterlogged
conditions.
 It is recommended for cultivation in those areas where water-
logging exists for about 60 days.
58

59. Thank you for patient hearing
59