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Developments in rice production in Southeast Asia

  • April 2002
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Ernst Mutert
Ernst Mutert
Ernst Mutert
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While some countries of Southeast Asia have increased productivity of rice in recent years, yields have stagnated in other countries of the region. The correlation to fertilizer nutrient use is clear, and there is great potential for increased production. Because of its political, economic, and social significance in the eight agricultural countries of the Association of Southeast Asian Na-tions (ASEAN), rice remains the most important crop grown in South-east Asia (SE Asia). The greatest levels of productivity are found in irrigated rice, where more than one crop is grown per year and yields are high (Table 1). Productivity is poor in upland systems where yields are small and only one crop is grown per year. Upland rice is usually grown without mineral fertilizer, and a long fallow period of at least eight years under secondary forest is required to generate soil fertility. Due to increased population pressure, such lengthy fallow periods are no longer fea-sible and upland rice is thus a major cause of land degradation and nutrient mining in many parts of the region. Irrigated and lowland rainfed systems account for more than 95 percent of rice production, so small productivity gains have a profound effect on total produc-tion. The significance of upland and deepwater rice systems lies in their contribution to food security and their impact on the environment in locali-ties within the region. Approximately 42 million (M) ha or 45 percent of SE Asia's cropped land is planted to rice in irrigated (18 M ha), rainfed (18 M ha), deep water (3 M ha), and upland (3 M ha) crop-ping systems. The largest area under irrigated rice is found in Indonesia, followed by Vietnam, the Philippines, and Thailand (Table 2).
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Better Crops International
Vol. 15, Special Supplement, May 2002
12
Southeast Asia
Developments in Rice Production
in Southeast Asia
By Ernst Mutert and T.H. Fairhurst
While some countries of Southeast Asia have increased productivity
of rice in recent years, yields have stagnated in other countries of the
region. The correlation to fertilizer nutrient use is clear, and there is
great potential for increased production.
Because of its political, economic, and social significance in the
eight agricultural countries of the Association of Southeast Asian Na-
tions (ASEAN), rice remains the most important crop grown in South-
east Asia (SE Asia). The greatest levels of productivity are found in
irrigated rice, where more than one crop is grown per year and yields
are high (Table 1). Productivity is poor in upland systems where yields
are small and only one crop is grown per year. Upland rice is usually
grown without mineral fertilizer, and a long fallow period of at least
eight years under secondary forest is required to generate soil fertility.
Due to increased population pressure, such
lengthy fallow periods are no longer fea-
sible and upland rice is thus a major cause
of land degradation and nutrient mining
in many parts of the region.
Irrigated and lowland rainfed systems
account for more than 95 percent of rice
production, so small productivity gains
have a profound effect on total produc-
tion. The significance of upland and
deepwater rice systems lies in their
contribution to food security and their
impact on the environment in locali-
ties within the region.
Approximately 42 million (M) ha
or 45 percent of SE Asia’s cropped
land is planted to rice in irrigated (18
M ha), rainfed (18 M ha), deep water
(3 M ha), and upland (3 M ha) crop-
ping systems. The largest area under
irrigated rice is found in Indonesia,
followed by Vietnam, the Philippines,
and Thailand (Table 2). The largest
TT
TT
Table 2.able 2.
able 2.able 2.
able 2. Area under irrigated, rainfed lowland (RLLR), upland, and other
rice cropping systems in SE Asia, 1995 (IRRI Rice Facts, 2002).
Irrigated RLLR Upland Flood prone Total area
Country - - - - - - - - - - - - - - - - ‘000 ha- - - - - - - - - - - - - - - -
Cambodia 154 1,124 33 614 1,924
Indonesia 6,154 4,015 1,247 23 11,439
Laos 40 319 201 — 560
Malaysia 445 152 84 — 681
Myanmar 1,124 4,166 252 602 6,144
Philippines 2,334 1,304 120 — 3,759
Thailand 2,075 6,792 36 117 9,020
Vietnam 3,687 1,955 345 778 6,766
Total 16,015 19,827 2,318 2,134 40,293
TT
TT
Table 1.able 1.
able 1.able 1.
able 1. A comparison of the productivity of four different rice systems.
Yield, Fallow Productivity,
System t/ha Crops/yr period, yr t/ha/yr
Irrigated rice 5.0 2.5 0 12.5
Rainfed rice 2.5 1 0 2.5
Deep water rice 1.0 1 0 1.0
Upland rice11.0 1 8 0.12
1Grown in slash-and-burn systems, usually on sloping land.
Better Crops International
Vol. 15, Special Supplement, May 2002
13
area under RLLR is found in Thailand, but
there are also large areas in Indonesia and
Myanmar. The largest area under upland
rice is found in Indonesia, and significant
amounts of land are planted in flood-prone areas in Cambodia, Viet-
nam, and Myanmar.
At present, SE Asia produces 150 M tonnes (t) of paddy per year
(25 percent of world production), of which 95 percent is consumed
within the region. While per capita demand is expected to decrease in
the future, total demand for rice in SE Asia is expected to increase to
more than 160 M t per year by 2020 due to population growth (Table
3).
The area under the most productive and fertile irrigated rice lands,
located in areas of high population density, is expected to decrease due
to the effects of rapid urbanization and industrialization. Thus, produc-
tivity in rice systems must increase from the
current average of 3.4 t/ha to at least 4 t/ha
if food security and export potential of SE
Asia are to be maintained.
In Indonesia and Vietnam, where more
than 50 percent of the planted area is un-
der irrigated rice, productivity increased
from 3.3 t/ha to 4.3 t/ha within one decade
during the recent past. This is attributed to
an expansion in the area under irrigation
and the increased use of modern varieties
(Table 4) and fertilizer nutrients (Table 5).
The national average yield in the Phil-
ippines, however, is only 3 t/ha (Table 4),
in spite of the greater use of modern variet-
ies and a greater proportion of total rice
land under irriga-
tion. This is partly
due to smaller inputs
of fertilizer nutrients
(Table 5).
National aver-
age yields for
Cambodia, Laos,
Myanmar, and
Thailand are also
small. The main con-
tributing factors are:
1) the lower yield
TT
TT
Table 3.able 3.
able 3.able 3.
able 3. Estimated population, rice production, and per capita rice
consumption in SE Asia.
Year
2000 2020 2050
Population, millions 520 650 780
Rice production, million tonnes 150 160 180
Per capita consumption, kg 270 250 230
TT
TT
Table 5.able 5.
able 5.able 5.
able 5. Growth rates for rice yields, fertilizer consumption, and rice imports in SE Asia.
Increase in rice yield, Increase in fertilizer Rice imports,
% per year consumption, % (1990-99) ‘000 t
Country 1967-90 1990-99 N P2O5K2O 1980-89 1990-99 Change
Cambodia 0.7 2.5 22.6 3.4 0 946 472 -474
Indonesia 4.0 0 4.6 -5.4 -1.0 4,915 13,784 +8,869
Laos 4.4 2.0 26.5 15.8 10.4 157 167 +10
Malaysia 1.6 0.5 3.7 4.7 6.5 3,150 4,409 +1,259
Myanmar 2.5 0.9 12.2 11.7 -2.3 0 0 0
Philippines 3.4 -0.4 0.3 1.8 2.1 1,044 5,898 +4,854
Thailand 0.5 1.5 6.2 4.7 9.6 0 2 +2
Vietnam 2.2 2.1 15.1 16.4 37.2 2,272 28 -2,244
TT
TT
Table 4.able 4.
able 4.able 4.
able 4. Rice area harvested and planted to modern varieties, 1999
(IRRI Agri Facts, 2002).
Area Area planted to
harvested, Yield, modern varieties
‘000 ha t/ha % ‘000 ha
Cambodia 1,961 1.94 11 216
Indonesia 11,624 4.25 77 8,951
Laos 718 2.93 2 14
Malaysia 674 2.94 6814581
Myanmar 5,458 3.24 72 3,930
Philippines 3,978 2.95 89 4,858
Thailand 10,000 2.33 68 6,800
Vietnam 7,648 4.11 80 6,118
SE Asia 42,061 3.48 75 31,345
1 PPI/PPIC ESEAP estimate, 2002
Better Crops International
Vol. 15, Special Supplement, May 2002
14
potential of the dominant rainfed
systems, 2) greater use of traditional
varieties instead of modern variet-
ies, and 3) less efficient management
of water and nutrients.
Achieving the required average
yield of 4.5 t/ha in SE Asia will likely
mean further increases in the area
under rice, a larger proportion of rice
systems under irrigation, and greater
use of adapted modern varieties. Adequate nitrogen (N), phosphorus
(P), and potassium (K) are also important. It is estimated that average
application rates of 73 kg N/ha, 24 kg P2O5/ha, and 33 kg K2O/ha will
be needed to meet the levels of production required in the next 10 years.
Between 1980 and 2000, the harvested area of rice in SE Asia in-
creased by 8.4 M ha to 43.4 M ha, the proportion irrigated increased
by almost 4 M ha, and the use of modern varieties increased to 75
percent of the total area planted to rice. Impressive yield gains of up to
2 t/ha have been achieved over the period 1980–2000 in the irrigated
and partly irrigated rice systems in SE Asia, but there has been little
progress in the rainfed systems (Figure 1). There was a consistent de-
cline in the rate of increase in rice yields compared with the 20-year
period following the introduction of modern varieties in the early 1960s.
During the last decade, average rice yields increased by about 1 t/ha.
Over the past three decades, Thailand has maintained its position
as the region’s major rice exporter (Figure 2). Vietnam was a rice im-
porter in the 1980s, but began to export rice during the 1990s, and in
2000 exported more than 4 M t. Increased production in both Thailand
and Vietnam is clearly correlated to the increased use of NPK fertilizers
during the past 20 years.
In contrast, rice productivity growth rates in Indonesia, Malaysia,
and the Philippines de-
creased during the
1990s, and rice imports
grew to almost 6.5 M t
in 2000 (Figure 2).
Rice imports for these
three countries totalled
24 M t in the period
1990–1999, an increase
of about 15 M t over the
total import for 1980–
1989 (Table 5). Growth
rates for the consump-
Figure 1.Figure 1.
Figure 1.Figure 1.
Figure 1. Rice yields in
major cropping systems in
SE Asia.
Figure 2. Figure 2.
Figure 2. Figure 2.
Figure 2. Trade deficits in
rice in SE Asia.
1970 1975 1980 1985 1990 1995 2000
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
Yea r
Rainfed
Partly irrigated
Fully Irrigated
Yield, t/ha
Indonesia
Philippines
Malaysia
Cambodia
Laos
Myanmar
Vietnam
Thailand
-6,000 -4,000 -2,000 0 2,000 4,000 6,000 8,000
Imports Rice trade ('000 t) Exports
2000
1990
1980
Better Crops International
Vol. 15, Special Supplement, May 2002
15
tion of NPK fertilizer nutrients were small or negative in Indonesia and
the Philippines during the 1990s, particularly following the economic
crisis in 1997. This has further increased their dependence on rice im-
ports.
To maintain regional self-sufficiency in rice, the irrigated and rainfed
rice systems must achieve yields of 6 t/ha and 3 t/ha, respectively, over
the next two decades. Major constraints to improving productivity in-
clude low soil fertility, pest and disease damage, competition from weeds,
drought in rainfed systems, flooding, soil acidity, poor infrastructure,
land fragmentation, and land losses due to urbanization, poor avail-
ability and high cost of inputs, low and fluctuating rice prices, land
degradation due to salinization, and poor extension services. Constraints
are presented in more detail in Table 6.
On-farm research conducted by the International Rice Research
Institute (IRRI) and the National Agriculture Research and Extension
Stations (NARES) on 118 farms in four SE Asia countries has shown
that the improved techniques of site-specific nutrient management
(SSNM) can contribute to productivity increases of 10 to 15 percent,
with an average increase in net farm income of about US$50/ha/crop or
US$100/ha/yr in double cropped systems. Yield and income gains were
much larger, however, in well-managed farms (Dobermann et al., 2002).
Successful implementation of SSNM, however, requires complementary
and comprehensive crop management techniques, including pest and
disease management, and the use of high quality seed. The research
showed that the impact of SSNM on yield and profitability were much
greater where farmers achieved high standards of general crop care.
This underlines the importance of “knowledge-based” approaches to
extension where farmers learn to integrate different techniques by fol-
lowing prescriptive and piecemeal recommendations.
The average annual fertilizer NPK consumption in rice systems of
SE Asia is estimated at 4.1 M t/yr (about 100 kg/ha) or about 50 per-
cent of total fertilizer NPK consumption in the region (Table 7). Nutri-
ent consumption appears to be unbalanced with an N:P2O5:K2O ratio
of about 8:2:1.
One consequence of unbalanced fertilizer use in the region is the
extent to which the K reserves in soils are being depleted. It is estimated
that at least 1 M t of K is mined each year from SE Asia’s rice soils, and
calculations based on research in intensified rice systems in Indonesia,
Thailand, the Philippines and Vietnam show negative balances for K of
40 to 60 kg K ha/yr (Sheldick et al., 2002; Syers et al., 2001). However,
when combined with improved N management techniques (i.e., more
precise timing and splitting of N fertilizer, use of a leaf color chart),
increased applications of K resulted in average yield increases of about
0.5 t/ha.
Better Crops International
Vol. 15, Special Supplement, May 2002
16
TT
TT
Table 6.able 6.
able 6.able 6.
able 6. Main production constraints for rice in SE Asia (modified after IRRI Rice Facts, 2002). White background indicates that a constraint exists in country indicated.
Cambodia Indonesia Laos Malaysia Myanmar Philippines Thailand Vietnam Total*
Low soil fertility Sandy soils 50% problem >75% 5
soils rice lands
Soil acidity 2
Salinity Intrusion of seawater NE and S coast Coastal areas 4
Drought Rainfed rice systems 8
Flooding Low lying areas Mekong River Typhoons In RLLR Rainfed areas 5
Low temperatures Upland rice in N Vietnam 2
N. Irrigated in
N and NE.
Pests and diseases Stem borer, BPH, stem borer, BPH, stem borer, RTV, BLB, Blast, BLB, blast, BPH, BPH, stem borer, 8
gall midge BLB, blast, RTV blast, GLV, RTV GLH, stem borer stem borer leaf roller, blast,
BLB, brown spot
Weeds Weeds in direct Direct Direct Weeds in direct 6
seeded rice seeded rice seeded rice seeded rice
Land fragmentation Small farm size Small farm size 3
Land security Land mines 1
Rural poverty 2
Labour scarcity In agriculture 2
production areas
High input cost Fertilizer 1
Input scarcity Infrastructure, Lack of Infrastructure, Infrastructure, Infrastructure, 4
credit, seed quality credit, seed credit, seed credit, seed
fertilizers, fertilizers fertilizers, fertilizers, fertilizers,
agrochemicals agrochemicals agrochemicals agrochemicals
Rice price policy Low price Low price Price policy 5
Ineffective extension 2
Water 2
management
Land loss Urban sprawl Erosion 2
Others New technology Preference for Limited market Lack of clear 4
required glutinous rice opportunity policy
Total* 10 10 12 6 10 7 8 12
*Total number of incidences where production constraints have been detected
Acid sulfate soils
Better Crops International
Vol. 15, Special Supplement, May 2002
17
The stagnation in rice yields and the consequent increase in rice
imports in Indonesia, Malaysia, and the Philippines are clearly related
to the low fertilizer K application rates averaging less than 10
kg K2O/ha in these countries. An estimated 1.3 M t K2O/yr and 1 M t
P2O5/yr are required to support the levels of rice productivity that will
be needed to maintain self-sufficiency in the region (Greenland, 1997).
The challenge in rice systems in SE Asia is to achieve regional food
security and increase farm incomes using site-specific integrated crop
management techniques. This will require much greater investments in
research and extension over the next two decades. BCIBCI
BCIBCI
BCI
Dr. Mutert and Dr. Fairhurst are Directors, PPI/PPIC East and Southeast Asia Program
(ESEAP), Singapore; e-mail: tfairhurst@eseap.org.
References
Dobermann, A., C. Witt, D. Dawe, S. Abdulrachman, H.C. Gines, R. Nagarajan, S.
Satawathananont, T.T. Son, P.S. Tan, G.H. Wng, N.V. Chien, V.T.K. Thoa, C.V.
Phung, P. Stalin, P. Muthukrishnan, V. Ravi, M. Babu, S. Chatuporn, J. Sookthongsa,
Q. Sun, R. Fu, G.C. Simbahan, and M.A.A. Adviento. 2002. Site-specific nutrient
management for intensive rice cropping systems in Asia, Field Crops Research 74,
pp. 37-66.
Greenland, D.J. 1997. The sustainability of rice farming. CAB International, Wallingford,
UK. 273 p.
International Rice Research Institute (IRRI). 2002. Website at http://www.irri.org.
Sheldrick, W.F., J.K. Syers, and J. Lingard. 2002. Conducting Nutrient Audits at the National
Scale in Southeast Asia: Methodology and Preliminary Results (In Press).
Syers, J.K., W.F. Sheldrick, and J. Lingard. 2001. Nutrient Depletion in Asia: How Serious
Is the Problem? In CAS and CIEC (eds.) 12th World Fertilizer Congress—Fertilization
in the Third Millennium. Chinese Academy of Sciences (CAS) International Scientific
Centre of Fertilizers (CIEC), Beijing, China, p. 6.
TT
TT
Table 7.able 7.
able 7.able 7.
able 7. Fertilizer NPK use by rice in major agro-economics of SE Asia 2001 (PPI-PPIC ESEAP estimates, 2002).
NP2O5K20Consumption
Area Fertilized Rate Fertilized Rate Fertilized Rate N P2O5K20
Country ‘000 ha % kg/ha % kg/ha % kg/ha ‘000 t Total Ratio
Cambodia 1,873 30 15 20 14 5 3 8.4 5.2 0.3 13.9 28.0: 17.3 :1.0
Indonesia 11,523 90 105 70 22 40 14 1,192.6 177.5 64.5 1,434.6 18.4:2.8:1.0
Laos 690 30 55 20 15 5 5 11.4 3.1 0.2 14.7 57.0:15.5:1.0
Malaysia 692 90 95 90 40 70 35 59.2 24.9 17.0 101.1 3.5:1.5:1.0
Myanmar 6,000 60 35 50 12 10 4 126.0 36.0 2.4 164.4 52.5:15.0:1.0
Philippines 4,037 85 51 85 15 75 11 175.0 51.5 33.3 259.8 5.3:1.5:1.0
Thailand 10,048 90 62 90 33 60 17 560.7 298.4 102.5 961.6 5.5:2.9:1.0
Vietnam 7,655 90 108 80 45 50 40 744.1 275.6 153.1 1,172.8 4.9:1.8:1.0
Total: 42,518 2,877.4 872.2 373.3 4,122.9
Ratio 8: 2: 1
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Thesis
  • Jun 2022
Flooding-induced phosphorus (P) dissolution causes favorable P regimes in lowland rice soils, but non-flooded rice production systems would reduce the P bioavailability that may have yield-limiting impacts. The present study aimed to evaluate the effect of different system-based sole fertilizer and integrated P management in improving productivity, economics, and P use efficiency of the non-flooded rice-lentil systems in tropical alkaline soil. Field experiments involving two non-flooded rice production techniques with seven different system-based P management treatments were conducted during 2015-2018 at Kanpur, India. The non-flooded rice cultivation techniques were direct seeded rice (DSR) and system of rice intensification (SRI). The system-based P treatments [subscript value represents fertilizer-P rate (kg P ha-1) to rice and lentil, respectively] were P control (P[0-0]), three sole fertilizer-P treatments with variable rate (P[22-22], P[33-11], P[11-33]), and three integrated treatments ([P11-11+phosphate solubilising bacteria (B)], [P16.5-5.5+rice residue recycling (RR)+B], [P5.5-16.5+lentil residue recycling (LR)+B]). The yield potential of DSR was lower than SRI crop, attributed to the reduced root growth, suboptimal N nutrition, and sink inefficiencies. The DSR system favoured lentil performance over the SRI system. The non-flooded rice production significantly reduced P availability (6-9%) in rice season compared to the flooded-rice production. The integrated P management involving suboptimal P rate with rice residue recycling and bacterial inoculation treatment (P16.5-5.5+RR+B) significantly increased Olsen-P in the rice (6-8%) and lentil (10%) crop seasons over the recommended sole fertilizer-P treatment (P[22-22]), leading to higher system productivity (8%), agronomic P use efficiency, fertilizer-P recovery efficiency, and net return (15%). The integrated treatment ‘P16.5-5.5+RR+B’ resulted in higher soil NaHCO3-extractable P (11%), dissolved non-reactive P (6%), macro-aggregates (13%), active carbon pools (8%), and water holding capacity (6%) over the treatment ‘P[22-22]’. The positive correlations of soil aggregation, labile C pools, and microbial biomass carbon with Olsen-P demonstrated their significance in P cycling. The marginally negative P balance in the crop residue recycling integrated treatments suggested that fertilizer-P rate needs to be precisely adjusted to ensure a positive balance. Hence, rice residue recycling integrated P management could improve soil P availability, system productivity, and profitability in the non-flooded rice-lentil systems, and save costly fertilizer-P.
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... Approximately 45% of the rice area in Southeast Asia is irrigated. (Mutert and Fairhurst, 2002). In 2010, approximately 154 million ha were harvested worldwide, of which 137 million ha (88% of the global rice harvested) were in Asia, of which 48 million ha (31% of the global rice harvested) were harvested in Southeast Asia alone (FAOSTAT, 2012). ...
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... The potential of the high-yielding varieties, especially of rice, seems to have been exploited. In the late 1990s, modern varieties of rice occupied around 75 per cent of the total rice area in the region, except Lao PDR and Cambodia (Mutert and Fairhurst 2002). Of late, there has also been a significant progress in agricultural mechanization (Kottmeyer, Fulginiti, and Lilyan 2016). ...
Transformation and Sources of Growth in Southeast Asian Agriculture
Article
  • Aug 2022
Over the past few decades, agriculture in Southeast Asia has experienced robust growth and undergone a significant structural transformation, albeit at a different pace in different countries in the region. This paper aims to understand the process of agricultural transformation and growth in Southeast Asia. The findings of this study show that, driven by technological change, area expansion and diversification, agriculture has grown faster in low-income countries in the region. In contrast, agricultural growth in high-income countries has been slow and driven by price increases, mainly of export-oriented commercial crops such as oil palm, rubber and coconut—alongside expansion of cropped area under these crops. In view of the fixed supply of land and high volatility in global food prices, the area- and price-driven growth is not sustainable in the long run. For efficient, sustainable and inclusive growth, exploiting the potential of existing and frontier technologies and diversification of production portfolio holds greater promise.
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... In Southeast Asia agriculture and food are key sectors, and this region is considered to be one of the largest agricultural producers worldwide. Rice, for example, is the most critical crop, and is a staple food source in the region [26]. The crop is of great significance to the local and regional economy [27]. ...
A Review of Earth Observation-Based Drought Studies in Southeast Asia
Article
Full-text available
  • Aug 2022
Drought is a recurring natural climatic hazard event over terrestrial land; it poses devastating threats to human health, the economy, and the environment. Given the increasing climate crisis, it is likely that extreme drought phenomena will become more frequent, and their impacts will probably be more devastating. Drought observations from space, therefore, play a key role in dissimilating timely and accurate information to support early warning drought management and mitigation planning, particularly in sparse in-situ data regions. In this paper, we reviewed drought-related studies based on Earth observation (EO) products in Southeast Asia between 2000 and 2021. The results of this review indicated that drought publications in the region are on the increase, with a majority (70%) of the studies being undertaken in Vietnam, Thailand, Malaysia and Indonesia. These countries also accounted for nearly 97% of the economic losses due to drought extremes. Vegetation indices from multispectral optical remote sensing sensors remained a primary source of data for drought monitoring in the region. Many studies (~21%) did not provide accuracy assessment on drought mapping products, while precipitation was the main data source for validation. We observed a positive association between spatial extent and spatial resolution, suggesting that nearly 81% of the articles focused on the local and national scales. Although there was an increase in drought research interest in the region, challenges remain regarding large-area and long time-series drought measurements, the combined drought approach, machine learning-based drought prediction, and the integration of multi-sensor remote sensing products (e.g., Landsat and Sentinel-2). Satellite EO data could be a substantial part of the future efforts that are necessary for mitigating drought-related challenges, ensuring food security, establishing a more sustainable economy, and the preservation of the natural environment in the region.
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... We estimated yield gaps based on the simulated yield potential (irrigated crops) or water-limited yield potential (rainfed crops) across the six major rice-producing countries in Southeast Asia (Cambodia, Indonesia, Myanmar, Philippines, Thailand and Vietnam), which together account for 97% of total rice production in the region 3 . Our assessment included both irrigated and rainfed lowland rice systems, which roughly account for 98% of total rice production in these six countries 13,15 , while deep-water and upland rice were not included. For irrigated rice, our definition of yield potential assumed no water and nutrient limitations and the absence of weeds, pests and diseases. ...
Southeast Asia must narrow down the yield gap to continue to be a major rice bowl
Article
Full-text available
  • Mar 2022
Southeast Asia is a major rice-producing region with a high level of internal consumption and accounting for 40% of global rice exports. Limited land resources, climate change and yield stagnation during recent years have once again raised concerns about the capacity of the region to remain as a large net exporter. Here we use a modelling approach to map rice yield gaps and assess production potential and net exports by 2040. We find that the average yield gap represents 48% of the yield potential estimate for the region, but there are substantial differences among countries. Exploitable yield gaps are relatively large in Cambodia, Myanmar, Philippines and Thailand but comparably smaller in Indonesia and Vietnam. Continuation of current yield trends will not allow Indonesia and Philippines to meet their domestic rice demand. In contrast, closing the exploitable yield gap by half would drastically reduce the need for rice imports with an aggregated annual rice surplus of 54 million tons available for export. Our study provides insights for increasing regional production on existing cropland by narrowing existing yield gaps.
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ESTIMATION OF RICE PRODUCTION FUNCTION IN THE PHILIPPINES USING PANEL DATA AMYLYN F. LABASANO Researcher
Thesis
Full-text available
  • Apr 2014
This study used panel data in analyzing the effects of the cost of machines, tools and equipments; labor costs; quantity of fertilizer; cost of seeds/planting materials; cost of crop protection products; and irrigation fees on the yield per hectare of rice. Panel data were utilized using fifteen (15) regions of the Philippines namely Bicol, Cagayan Valley, Cordillera Administrative Region (CAR), Central Luzon, Ilocos, Southern Tagalog, Central Visayas, Eastern Visayas , Western Visayas, Northern Mindanao, Southern Mindanao, Western Mindanao, Central Mindanao, CARAGA and ARMM over the 12 periods, 1991 to 2002. Regression analysis was applied to the irrigated and non-irrigated areas. One hundred eighty (180) samples points were utilized. The study ran four (4) models, each for irrigated and non-irrigated rice areas. These four models consisted of different combinations of the explanatory variables to test the consistency of the factors that contribute significantly to the yield per hectare of palay. All models were of the unconstrained Cobb-Douglas type production function. All explanatory variables, except the fertilizer which was in kilograms, were deflated using the GDP deflator. The result of the analysis revealed that in the irrigated rice area, the three explanatory variables, namely: fertilizer, crop protection, and irrigation fees had regression coefficients which were highly significant in all models. It should be noted that fertilizer was in kilograms while crop protection products (agri-chemicals) and irrigation fees were deflated peso values of these variables. The remaining three (3) explanatory variables namely, labor, machines, and seeds gave regression coefficients that were not significant. In other words, the marginal product of these variables or factors of production were statistically equal to zero. While in the non-irrigated model, results of the regression analysis showed that three (3) variables namely, fertilizer, machines, and crop protection products gave significant regression coefficients in all regression runs. Two variables (labor and seeds) were not significant but seeds gave varying results. The significant explanatory variables of the models could explain about two-thirds of the total variation of the yield per hectare of palay in both irrigated and non-irrigated rice areas.
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Site-specific nutrient management for intensive rice cropping systems in Asia
Article
Irrigated rice (Oryza sativa L.) yield increases in Asia have slowed down in recent years. Further, yield increases are likely to occur in smaller increments through fine-tuning of crop management. On-farm experiments at 179 sites in eight key irrigated rice domains of Asia were conducted from 1997 to 1999 to evaluate a new approach for site-specific nutrient management (SSNM). Large variation in initial soil fertility characteristics and indigenous supply of N, P, and K was observed among the eight intensive rice domains as well as among farms within each domain. Field- and season-specific NPK applications were calculated by accounting for the indigenous nutrient supply, yield targets, and nutrient demand as a function of the interactions between N, P, and K. Nitrogen applications were fine-tuned based on season-specific rules and field-specific monitoring of crop N status. The performance of SSNM was tested for four successive rice crops. Average grain yield in the SSNM increased by 0.36 Mg ha−1 (7%) compared to the current farmers’ fertilizer practice (FFP) measured in the same cropping seasons or 0.54 Mg ha−1 (11%) compared to the baseline FFP yield before intervention. Average nutrient uptake under SSNM increased by about 10% in the same seasons or by 13% (N) and 21% (P, K) compared to the baseline data. Yield increases were associated with a 4% decrease in the average N rate, but larger amounts of fertilizer-K at sites where the previous K use was low. Average N use efficiencies increased by 30–40%, mainly through the use of improved in-season N management schemes. Across all sites and four successive rice crops, profitability increased by US$ 46 ha−1 per crop or 12% of the total average net return. The performance of SSNM did not differ significantly between high-yielding and low-yielding climatic seasons, but improved over time with larger benefits observed in the second year. Average profitability increased from US$ 32 ha−1 pre crop in the first year to US$ 61 ha−1 pre crop in the second year due to improvements in the SSNM approach and re-capitalization of P and K applied in the first year. SSNM required little extra credit for financing, and remained profitable even if rice prices are somewhat lower than current levels. Further, scope for improvement exists at many sites by alleviating other crop management constraints to nutrient use efficiency. Profit increases ranged from US$ 4 to 82 ha−1 per crop among eight rice domains. However, profit decreases occurred in about 25% of all cases, indicating that a certain minimum level of crop care is required for SSNM to be profitable. Yields at sites with labor-saving direct-seeding of larger fields were about 1 Mg ha−1 lower than those achieved at sites with labor-intensive transplanting and good management, raising concern about future trends in rice production. SSNM has potential for improving yields and nutrient efficiency in irrigated rice to close existing yield gaps. The major challenge for SSNM will be to retain the success of the approach while reducing the complexity of the technology as it is disseminated to farmers. The nature of the approach will need to be tailored to specific circumstances in different countries. In some areas, SSNM may be field or farm specific, but in many areas it is likely to be just region and season-specific.
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12 th World Fertilizer Congress-Fertilization in the Third Millennium
  • Jan 2001
  • 6
  • J K Syers
  • W F Sheldrick
  • J Lingard
Syers, J.K., W.F. Sheldrick, and J. Lingard. 2001. Nutrient Depletion in Asia: How Serious Is the Problem? In CAS and CIEC (eds.) 12 th World Fertilizer Congress-Fertilization in the Third Millennium. Chinese Academy of Sciences (CAS) International Scientific Centre of Fertilizers (CIEC), Beijing, China, p. 6.
Conducting Nutrient Audits at the National Scale in Southeast Asia: Methodology and Preliminary Results
  • Jan 2002
  • W F Sheldrick
  • J K Syers
  • J Lingard
Sheldrick, W.F., J.K. Syers, and J. Lingard. 2002. Conducting Nutrient Audits at the National Scale in Southeast Asia: Methodology and Preliminary Results (In Press).