Vol.2, No.4, 511-517 (2011)
doi:10.4236/as.2011.24066
C
opyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
Agricultural Sciences
Improving the water productivity of paddy rice (Oryza
sativa L.) cultivation through water saving irrigation
treatments
Joko Sujono1*, Naoki Matsuo2, Kazuaki Hiramatsu3, Toshihiro Mochizuki3
1Department of Civil and Environmental Engineering, Faculty of Engineering, Gadjah Mada University, Yogyakarta, Indonesia;
*Corresponding Author: jsujono@ugm.ac.id
2Lowland Crop Rotation Research Team, National Agricultural Research Center for Kyushu Okinawa Region, Chikugo, Japan;
3Department of Agro-Environmetal Sciences, Faculty of Agriculture, Kyushu University, Fukuoka, Japan.
Received 11 August 2011; revised 10 October 2011; accepted 27 October 2011.
ABSTRACT
Rice grows well under certain condition and
environment including soil, water and nutrients.
Some researches have shown that traditional
method with continues flooding need tremen-
deous amount of water for rice cultivation and
gives low water productivity. To increase the
water productivity, number of water saving iriga-
tion techniques have been studied and applied.
Study on effect of number of water irrigation
treatments on water productivity of rice was
carried out. Eight irrigation treatments were
conducted for growing rice in pot experiment i.e.
shallow intermittent irrigation (SII), alternate
wetting and drying (AWD1, AWD2, AWD3 and
AWD4), shallow water depth with wetting and
drying (SWD1 and SWD2), and semi-dry cultiva-
tion (SDC). The performance of those treat-
ments in terms of agronomic and water pa-
rameters was compared to the shallow inter-
mittent irrigation as a control method. The study
reveals that the shallow intermittent irrigation
needs the highest amount of water compare with
other treatments. The lowest amount of water
was achieved under the semi-dry cultivation. It
could save water up to 18.4% compare to the
control trea tment. By usin g the al ternat e wetting
and drying and the shallow water depth with
wetting and drying treatments, irrigated water
can be reduced up to 13.1% and 5.4%, respec-
tively. The hi gh est g rain was o btained by alternate
wetting and drying (AWD4) and the semi-dry
cultivation yielded the smalest grain . On average
the alternate wetting and drying and shallow
water depth with wetting and drying increased
the grain yield by 22.9% and 17.9%, whereas the
semi-dry cultivation reduced the y i eld up to 14%
compare to the shallow water depth treatment.
The alternate wetting and drying treatments
have significantly improved the water produc-
tivity by 41.6% , shallow water d epth with wetting
and drying increased by 24.2% relative to the
shallow intermittent irrigation treatment, whereas
the most saving water treatment i.e. the semi-
dry cultivation performed quite similar with the
shallow water depth treatment, as a result of low
grain yields under the treatment.
Keyw ords: Pot Experiments; Water Management;
Wetting and D rying
1. INTRODUCTION
Rice is important crop for billian people. In 2008, the
rice consumption in Asia reached 400 million ton, around
90% of the world rice consumption [1]. For producing
rice, a tremendous amount of water is used for the rice
irrigation under the traditional irrigation technique called
as a continuous deep flooding irrigation technique. In
this technique, the paddy fields are inundated all the time
starting from transplanting until nearly harvesting (e.g.
[2]) at certain water depth that varies from 50 mm to 100
mm. Almost 80% of water resources availability is used
for irrigation purposes.
Currently, the traditional irrigation technique is get-
ting difficult to be applied due to facing number of
problems. The most obvious problem is decreasing trend
in the water resources availability especially during dry
season. On the other hand, the water demands for do-
mestic and industrial water supply are increasing. As a
result, the water availability for agriculture purposes is
decreasing and conflicting among the water user and
among farmers can not be avoided. Moreover, the tradi-
J. Sujono et al. / Agricultural Sciences 2 (2011) 511-517
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
512
tional irrigation technique has also been reported only
yields a low of rice or low water productivity (e.g. [3]).
There is a major challenge for paddy rice cultivators
to increase the water productivity. To grow rice with
much less water is necessary and possible [4]. Research
has been conducted to increase the water productivity for
growing rice [2,3,5-9]. The formal research on water
saving irrigation (WSI) treatments for paddy rice in
China was started around 1985. The impetus came from
different aspects such as shortages of food and electricity
as well as water demand for industrial, domestic in-
creased sharply. The research on improvement of water
management for paddy rice was given priority for fund-
ing from the Government [2]. A number of WSI treat-
ments have been studied. Among the available treat-
ments include the system of rice intensification (SRI),
alternate wetting and drying (AWD), shallow water depth
with wetting and drying (SWD), and semi-dry cultiva-
tion (SDC) as the following.
1.1. System of Rice Intensification
System of rice intensification (SRI) is an innovative
paddy cultivation method attaining high paddy yields
with lower resource of input both water and fertilizer or
cost saving. SRI was developed initially in the 1980s in
Madagascar by Henri de Laulanie, a French Jesuit who
spent more than three decades in Madagascar trying to
devise better rice production method (e.g. [6]). The main
feature of SRI regarding to water treatment is keeping
the soil both moist and aerated so that roots have access
to both water and oxygen. Great results of SRI practice
have been reported in number of countries [6,10-12].
Uphoff and Randriamiharisoa [13] reported that double
even triple yields over those of traditional rice culture
were obtained by SRI in Madagascar. However, criti-
cisms of these reports on SRI were made by some re-
searchers such as [14-16] for the extraordinary yields,
effectiveness of SRI practices and experimental proce-
dures. Despite of the skeptics present of SRI, Horie et al.
[17] explained that basic elements of SRI have proven
potential to increase rice yield. Thus, if the elements of
SRI are satisfied, SRI could be a high-yielding rice sys-
tem.
1.2. Shallow Water Depth with Wetting and
Drying
The feature of shallow water depth with wetting and
drying (SWD) is comprehensive application of shallow
water depth. Shallow water depth is equals to 10 - 40
mm water depth on the surface of soil. The SWD has
been spread widely in the southern provinces of China
since 1980s. The standard water control adopted in the
region is in the range of 60% SMC (saturated moisture
content) to 40 mm. However, the extra limit levels up to
70 mm are set up for storing more rainfall and drainage
occurs when the water level goes beyond the limit (e.g.
[3,18]).
1.3. Alternate Wetting and Drying
The alternate wetting and drying (AWD) irrigation
technique by 2002 has been adopted on 40% of the rice
growing areas in China. However many scientific issues
remain to be addressed and the application of the AWD
techniques in some regions is still very difficult because
of both biophysical and socio-economic problems. Ex-
perience shows that demonstrations and training are
needed to encourage farmer for applying the AWD [3].
The main feature of field water control under AWD is
that paddy fields is intermittently submerged and dried.
With the AWD treatment, there is no ponded water layer
in paddy field for most of the season. It implies that
fields are not kept continuously flooded but are allowed
to dry intermittently beginning 30 days after transplanting
of the crop. In the AWD the paddy field is submerged for
3 - 5 days with the water depth equal to about 30 mm
and then allowed to dry naturally up to 70% SMC.
Standard of field water control is between 70% SMC as
the lower limit and the upper limit is set up to 30 mm [3].
This practice allows paddy fields to reach a relatively
dry condition prior to receipt of further water and store
more water after rainfall. As a result, the utilization of
rainfall is optimum and the irrigation water requirement
reduced greatly. As this practice reduces irrigation water
use so the water productivity is increased greatly. The
AWD practice increases the water productivity on-farm
level remarkable up to 1.52 kg/m3 of water compare with
the traditional one i.e. 1.04 kg/m3 of water on average in
the four provinces in China [3].
1.4. Semi-Dry Cultivation
There is a great difference of field water control be-
tween semi-dry cultivation (SDC) and SWD as well as
AWD. For SDC, the water depth is maintained only in
the revival of green to the middle stage of tillering, and
there is no water depth on paddy field in the other stages
in entire growing season. The standard of field water
control is between 70% SMC as lower limit and the up-
per limit is 0 mm, except in the beginning stages up to
30 mm. Comparing between SWD and AWD, SDC is the
most high water efficiency. The water productivity could
reach 70% higher than traditional continuous flooding
technique [3].
J. Sujono et al. / Agricultural Sciences 2 (2011) 511-517
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
513513
2. MATERIAL AND METHODS
2.1. Experimental Site
The experiments were conducted at Kyushu University
Experimental Farm, Fukuoka, Japan (33˚37'N, 130˚27'E)
from mid August until beginning of November 2006
using pots with 15.6 cm diameter and 20 cm height.
Each pot weight is measured using an available scale.
Water was added to make a puddle soil. Scale was then
used to measure the added water weight. The soil mois-
ture suction of the soil was simply measured by using
Daiki tensiometer (DIK-3162 pressure gauge type).
Rice variety used for the experiment was Nipponbare.
The SRI method for transplanting was adopted i.e. young
seedling of 9 days after seeding and single seedling for
each pot was applied. Fertilizers used in the experiments
consists of 0.24 g/pot of N, 0.24 g/pot of P and 0.24
g/pot of K. One third of N and full doses of P and K
fertilizers were applied at 7 days after transplanting
(DAT). One third of N fertilizer was applied at growing
stage (25 DAT) and the remaining of N fertilizer used as
dressing was given at the panicle initiation stage i.e. at
40 DAT.
In the experiment, the number of tillers was counted
for 10, 20, 30, 40, 50, 60 and 70 DAT. Based on the till-
ers, the effect of water irrigation treatments was ana-
lyzed by comparing with the tillers number resulted un-
der shallow intermittent irrigation (SII) as a paddy con-
trol. The SII is chosen due to less water needed compare
to continuous flooding (traditional method). An example
of SII that has getting much attention is SRI practice.
The maximum productive tillers among the treatments
are the most potential treatment to yield the highest
spikelets or grain results, whereas water irrigation used
and the resulted grain affect to the water productivity.
2.2. Water Saving Irrigation Treatments
Eight water irrigation treatments were tested in the
study. Each treatment consists of three pot replicates.
The amount of irrigated water and when it should be
irrigated vary among the treatments and depend on eva-
potranspiration rate, soil moisture condition and the wa-
ter irrigation treatment used. For this purpose, daily
measurement of the pot weight was carried out. The
main features of the water irrigation treatments are de-
scribed as the following.
2.2.1. Shallow Intermittent Irrigation (SII)
In this treatment, shallow intermittent irrigation (SII)
[19] was applied where the maximum water depth was
set up at 20 mm and then it dries naturally. The irrigated
water was added when the depth reaches 0 mm (satu-
rated condition) or up to small cracks emerging (soil
moisture suction up to –10 kPa). This kind of water
treatment was applied for entire growing period from
transplanting up to ripening. An example of SII that is
normally applied in paddy rice cultivation is the SRI.
2.2.2. Alternate Wetting and Dry i ng (AWD)
The feature of water management for AWD is that
paddy pot is intermittently submerged and drying. The
maximum water depth was set up to the maximum level
at 20 mm and the minimum is 70% SMC (saturated
moisture content) or when the soil moisture suction
reaches 70 kPa. In this study, four different AWDs were
designed based on the starting point of no water depth
i.e.: AWD-1, alternate wetting and drying begin at 20
DAT; AWD-2, alternate wetting and drying begin at 30
DAT; AWD-3, alternate wetting and drying begin at 40
DAT, and AWD-4, alternate wetting and drying begin at
50 DAT.
2.2.3. Combining Shallow Water Depth with
Wet ti ng a nd Drying (S WD)
In the SWD the maximum water depth was set up to
20 mm while the minimum was at 70% SMC. In this
study two types of SWD were used i.e. SWD-1 for water
management where the drying begins at the middle stage
of tillering (in this study at 20 DAT) and SWD-2 when
the drying begins at the late stage of tillering (40 DAT).
Shallow water depth (maximum is 20 mm and minimum
is 0 mm water depth) were applied up to tillering, during
elongating and flowering stage, whereas wetting and
drying treatments were applied continuously from milk
ripening until ripening.
2.2.4. Semi-Dry of Cultivation (SDC)
There is a great difference of water irrigation treat-
ment between the SDC and the above mentioned. For the
SDC, shallow water depth is only maintained up to
tillering stage. The maximum water depth is 20 mm.
There is no water depth in the other stages in entire
growing season. In these stages, the maximum water
depth is 0 mm and the minimum is 70 SMC. The SDC
water irrigation treatment was started where no water
depth begins at the middle (20 DAT) stage of tillering.
3. RESULTS AND DIS CUS SION
3.1. Agronomic Parameters
Average tillers number under different water man-
agement treatments are given at Figure 1. The figure
clearly shown that up to 40 DAT there is no significant
difference among the treatments, however, starting at 45
DAT, the SII method gives more tillers than others. Un-
J. Sujono et al. / Agricultural Sciences 2 (2011) 511-517
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514
der the AWDs, however, the number spikelets are sli-
ghtly better than others. The differences are not signifi-
cantly different at 0.05 probability level according to
Duncan’s multiple comparison test (Table 1). Better
performance of the AWDs is probably due to the com-
bined effect of alternating and drying processes that cre-
ating aeration soil more frequently than other treatments
and young transplanted seedling. Wetting and drying
improves the root system environment, so that the root
system has enough oxygen and water during tiller de-
velopment.
given during paddy rice cultivation started from trans-
planting up to ripening stage excluding water needed for
land preparation. The irrigated water is purely for rice
growing since there is no either seepage or percolation
from the pot experiments. The irrigated water require-
ment varies depending on water irrigation treatments as
presented in Table 2. Amount of irrigated water and wa-
ter saving compared to paddy control (SII) are also given
in Table 2.
0
10
20
30
10 25 40 55 70
Tillers number
Days after transplanting
SII AWD-1
AWD-2 AWD-3
AWD-4 SWD-1
SWD-2 SDC
According to Horie et al. [17], transplanting young
seedling has advantages than aged ones (traditional
method). The advantages lie in higher tolerance to trans-
planting stresses in younger seedling than aged ones.
However, not all these tillers develop to maturity (pro-
ductive tillers), some degenerate to become dormant when
young and some die later, depending on environmental
and nutritional conditions [17] as shown in Table 1.
3.2. Water Parameters
Water management embraces the control of water for
optimum rice yield and the best use of a limited supply
of water. Water required to produce optimum yield i.e.
irrigated water must satisfy the evapotranspiration needs
of the paddy rice and losses through percolation and see-
page. In this study, irrigated water is the amount of water
Figure 1. Effect of water treatments on tillers number during
vegetative growth.
Table 1. Water saving for different water saving irrigation treatments.
Water saving relative to control
WSI treatment Irrigated water
(mm) mm %
SII (control) 861 0 0
AWD-1 711 150 17.4
AWD-2 736 124 14.4
AWD-3 781 79 9.2
AWD-4 762 98 11.4
SWD-1 783 78 9.1
SWD-2 846 14 1.7
SDC 703 158 18.4
Table 2. Number of tillers and spikelets under different water irrigation treatments.
Number of tillers Spikelets
Water treatment 45 DAT Productive Total Per panicle
SII (control) 25.0a 16.7ab 1204ab 72.3ab
AWD-1 23.7ab 16.0b 1098
b 68.7bc
AWD-2 24.0ab 16.7ab 1182ab 71.0ac
AWD-3 23.0ab 16.3ab 1223ab 75.1a
AWD-4 22.0b 17.3ab 1303a 75.6a
SWD-1 22.0b 17.7ab 1163ab 65.9c
SWD-2 23.0ab 19.0a 1329a 70.2ac
SDC 22.7ab 18.0ab 1190ab 66.1c
Note: In a column, means followed by a different letter are significantly different at the 0.05 probability level according to Duncan’s multiple comparison test.
Openly accessible at
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515515
The table shows clearly that AWD, SWD and SDC
treatments reduce the amount of water needed for paddy
rice cultivation compared to the SII as a control treat-
ment. The irrigated water reduction varies from 1.7% to
17.4%. In terms of irrigated water, the SDC is the most
promising method for water saving treatment, since un-
der SDC there is no standing water in the paddy field
and most of the time the soil is below saturated condition.
In addition for reducing irrigated water, the irrigation
treatment under SDC offers longer irrigation time inter-
val. That is more appropriate in practice compared with
the SII (for instance SRI), since to maintain the soil un-
der saturated condition as in the SII treatment is not an
easy task in real paddy fields. Longer irrigation interval
is important factor for irrigation water management es-
pecially for large area, rotation irrigation delivery system
due to limited water.
3.3. Water Productivity
The water productivity is defined as the amount of
filled spikelets or grain produced per unit quantity of
water. The water productivity is obtained by dividing the
total grain produced in each pot (g grain) by the total
amount of water used (kg–1 water). As total irrigated wa-
ter used and the yield vary among water irrigation treat-
ments, their water productivity will have different values
as shown in Table 3.
Table 3 shows that the AWDs produced more grain
yield than other treatments. The increasing grain yield
relative to the SII could reach 42% under AWD-4. On
average the AWD and SWD increased the grain yield by
22.9% and 17.9%, whereas the SDC reduced the yield
up to 14% compare to the SII treatment.
Due to reducing supply of water using intermittent ir-
rigation especially in AWDs (Table 2) and relatively
higher grain yield compare with other treatments (Table
3), the water productivity under AWDs treatments were
higher than others. Irrespective to irrigated water and
consumptive water use, the water productivity with
AWD-1, AWD-2 and AWD-4 increase by 44.8%, 39.6%
and 60.2% compared to SII treatments, respectively. On
average AWDs treatments have significantly improved
the water productivity by 41.6%, SWDs increase by
24.2% relative to the SII treatments. On the other hand,
the SDC performs quite similar with the SII treatments,
since the grain yields under SDC treatment was less than
the SII.
Table 3 shows that all the treatments give very low
water productivity compare to other study results. For
instance, Chapagain and Yamaji [9] based on experi-
mental research conducted in Japan reported that com-
binations of practices in the intermittent irrigation plots
yield 1.74 g grain/kg water with SRI management and
AWD as compared to 1.23 g grain/kg water from nor-
mal planting methods with ordinary water management.
The low yield caused by cold damage is probably oc-
curred in the experiment. The damage affects to the rice
growing especially during flowering and grain filling
stages, since in the experiment the flowering started at
the mid of October that is to late for paddy rice cultiva-
tion in Japan. As a result, the unfilled spikelet became
very high for all the treatments, it reached 60% to 75%
of the total spikelet that is very high compare to the
normal condition i.e. less than 20%.
3.4. Selection of the M ost Appropriate Water
Saving Irrigation Treatments
The most appropriate water saving irrigation treatment
of rice cultivation will depend on a number of factors
including natural resources condition (soil, topography,
climate) and socio-culture (farmer condition). Number of
criteria could be used for selecting the most approprite
water saving irigation treatment including grain yield,
amount of irrigated water needed, water availability and
accesbility, water productivity and practicality.
Table 3. Yield and water productivity for different water irrigation treatments.
Yield Water productivity
Treatment
(g/pot) % difference
Water
(g) (g grain/kg water) % difference
SII (control) 8.41 0.0 16879 0.50 0.0
AWD-1 10.05 19.5 13940 0.72 44.8
AWD-2 10.04 19.4 14445 0.70 39.6
AWD-3 9.30 10.7 15324 0.61 21.9
AWD-4 11.93 41.9 14950 0.80 60.2
SWD-1 8.88 5.6 15352 0.58 16.1
SWD-2 10.94 30.2 16597 0.66 32.4
SDC 7.21 –14.2 13781 0.52 5.0
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516
Grain yield is not the only factor that attract the
farmers to apply the current the sugested method. Even
though the SII management practices yields much higher
grain than the traditional (continuous flooding) as re-
ported by many researchers [6,12,20], it takes time for
farmers to apply the SRI management practice that
mainly consist of using young seedling, one seddling per
hill, soil moist condition, wider spacing. Even at the
some places, the farmers do not want to try it due to they
think it is labour intensive (e.g. [21,22]), difficult to
maintain especially weeding the weed that grow fastly
due to there is no ponding water and keeping the soil at
moist condition rather than flooded (e.g. [22]).
In terms of maintaining the water in the paddy field, it
is likely that the AWD could be accepted by the farmers
not only due to yield higher grain and water productivity
that others water saving irrigation (see Tabl e 3) but also
more reliable in practice. The irrigation water interval is
much longer than SRI current practice, it is appropriate
for paddy field that used rotation irrigation system due to
limited water supply and the AWD is easier for farmers
to use than aerobic rice systems like the SDC (e.g. [23]).
The use of combination between the SRI management
practice and AWD for paddy rice cultivation is also
supported by others [9,20,22]. Uphoff [20] mentioned
that the SRI water management practices currently rec-
ommended may still be suboptimal for many conditions,
with more water reduction possible. Based on the ex-
periment combining between the SRI current manage-
ment practice with AWD increased water productivity
significantly than the normal method (e.g. [9,22]).
4. CONCLUSIONS
The experiment revealed that the amount of irrigated
water for paddy rice cultivation, grain yield and water
productivity are highly depends on the water irrigation
treatment used. A combination between the SII current
management practice and other water irrigation treat-
ments could increase the water productivity by reducing
the water irrigated used and increasing the grain yield.
Among the water irrigation treatment tested together
with the SII management practice, the AWD is the most
promising one followed by SWD, the SII current man-
agement practice and the SDC due to the following:
1) The AWD could reduce the irrigated water up to
13.1% compared with the SII method, whereas the
SWD and SDC reduced the water up to 5.4 and
18.4, respectively.
2) On average the AWDs and SWDs increased the
grain yield by 22.9% and 17.9%, whereas the SDC
reduced the yield up to 14% compare to the SII
treatment.
3) The AWDs treatments have significantly improved
the water productivity by 41.6%, the SWDs in-
crease by 24.2% relative to the SII treatments. On
the other hand, the SDC performs quite similar
with the SII treatments, since the grain yields un-
der SDC treatment was less than the SII.
5. ACKNOWLEDGEMENTS
The authors thank to the Hitachi Schollarship Foundation for the
financial support to conduct the experiment in Kyushu University
Fukuoka Japan. The experiment was conducted at the Kyushu
University Experimental farm.
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