|IRC: 02/05 |
THE INTERNATIONAL RICE COMMISSION
Bangkok, Thailand, 23-26 July 2002
ISSUES AND CHALLENGES IN RICE TECHNOLOGICAL DEVELOPMENT FOR SUSTAINABLE FOOD SECURITY
Rice is the most important food crop with more than 90% of global production occurring in tropical and semi-tropical Asia. In several Asian countries, rice provides 50 - 70% of the energy and protein dietary requirements. Rice is also a staple food in many Latin America and Caribbean countries, with consumption levels among the low income strata approaching the levels witnessed in Asia. Rice is the most rapid growing food source in several African countries and Nigeria has emerged as a major importer of rice. Rapid acceleration of rice production over the last three decades was a primary contributor to improvements in world food security. However, there are still 800 million people suffering from food deficits, most of them reside in areas that are dependent upon rice production for food, income, and employment.
Since the 19th Session of the International Rice Commission (IRC) held in Cairo, Egypt in 1998, there have been numerous developments that have profound impacts on the global rice industry. Rice production continued to expand and exceeded consumption, while several countries commenced to disperse the accumulated huge rice stocks pulling down the prices of rice in international markets. In several countries the increased incomes led to a downward trend in per-capita rice consumption. Low rice prices are a concern for rice exporting countries and importing countries that also have domestic production since this could be threatened by less expensive imported rice. The depressed economic situation in rice and large government support to maintain national production and rural incomes may have serious consequence for World Trade Organization members and their commitment under the Uruguay Round Agreement on Agriculture.
With the wide adoption of hybrid rice, China witnessed production increases, while there was a decrease in the area devoted to rice during the early 1990s. Biotechnological tools for manipulating rice genetics are in an early development stage but held promise for addressing several constraints in plant breeding. Improved techniques and more genomic information have brought rice biotechnology to the forefront of the science. Despite positive developments, polarization between opponents and supporters of transgenic food crops has intensified and represents a serious issue for future access and adapting genetically transformed rice varieties.
This paper examines the current situation in rice production with the objective of highlighting issues and concerns for economically sustainable production. Addressing the current situation and long-term rice demands are not separate issues since remedies to the current crisis could have major influence on meeting future needs.
Information on global rice production, consumption and ending stocks from 1997 to 2001/02 are presented in Fig. 1. These data illustrate the two distinct phases that have transpired over the last five years. During the three years from 1997 through 1999, production exceeded consumption. Over production was mainly a result of a combination of favorable international prices in prior years, support prices and government support to the export in several producing countries. Following the surplus years, global rice production has declined during the last two years; consumption has outpaced production. Global stocks also have decreased in order to compensate for the production decline. However, the global stocks during the last two years were still high. The production trend is expected to continue until the stocks of rice reach a more realistic level and demand and supply factors elevate international rice prices.
During the early 1990s, several scientists warmed of a pending crisis (Agcaoili and Rosegrant, 1992). The rice production growth rate decelerated from above 2.5% during the 1980s to only 1.1 % per annum during the early 1990s due to the slow growth in yield and limited expansion of production area. Several reports stated that a 75% increase in production will be required by the year 2025 to meet the demand of approximately 850 million tonnes of paddy (Pingali, et al, 1997). However, more recent analysis indicate lower demand for rice in both near-term (2010) and long-term (2030). These projections are based upon more recent consumption trends that take into account the decreasing per capita rice consumption due to urbanization and increased incomes. Between 2002 and 2010, rice consumption in China, is projected to decrease at a rate of approximately 0.45% per year (Table 1). In other Asian countries, consumption is forecast to remain stagnant. The same scenario is projected through 2030 (Table 2). Projections of economic growth of 4 - 5%/year is the driving force behind the anticipated reduction in rice consumption (Table 3).
In summary, rice demand in year 2030 is projected to be approximately 533 million tonnes of milled rice. This is significantly less than earlier projections but still a considerable quantity of rice will be required to meet future needs. Moreover, although global rice projections do not anticipate deficits, they often mask regional or national needs. Indonesia is projected to continue to experience rice deficits that are projected to increase from the current annual level of 3.6 to over 4.4 million tonnes in 2010 (Table 1). Currently, Nigeria imports annually about 1 million tonnes and this is projected to grow to 1.8 million tonnes in 2010. Sub-Saharan Africa is projected to import annually over 6 million tonnes by the year 2010. Brazil, Cuba and Mexico are projected to continue experience rice deficits of approximately 1.5 million tonnes/year.
Several emerging issues may hinder the ability to meet future rice needs. Yield stagnation and limited land and water resources for expanding rice area are the most important constraints to sustainable rice production. Concerns for, nutritional quality, genetic erosion, and environmental degradation require more stringent choices in rice production, especially under international commitment.
The growth in rice yields has decelerated to slightly more than 1% per year or approximately equal to population growth (FAO, 2002). Yield-stagnation appears to be a problem even with hybrid rice (Yuan, 1998). There is considerable information indicating declining yields/productivity in 28 million hectares of irrigated rice under intensive cultivation in Asia. Reports emerged in the early 1980s showing a yield decline in the intensively cultivated rice plots within research stations in the Philippines (Flinn, et al, 1982, 1994). Subsequent studies in several other countries also reported yield declines (Cassman, et al, and 1995,1996). More recent analyses support the earlier reports of declining yields from research trials but could not ascertain the extent of the decline in other areas of Asia, due to year to year variation in yields (Dawe, and Doberman, 2000). There are other observations indicating that continuous cultivation of irrigated rice, where the soil is maintained in anaerobic conditions for prolonged periods, does result in disorders that limit yield (Pulver and Nguyen, 1998). Paramount among the constraints is the production of toxins from anaerobic decomposition of organic matter that may limit plant development and subsequently yield (Olk, et al., 1996). Due to the importance of the intensive production system, attention must be directed toward sustaining high yields and avoiding inducing yield-limiting factors.
Also, it has long been known that irrigated rice production is highly vulnerable to a major biological attack due to genetic uniformity. In the 1980s, IR 36 was grown on approximately 13 million ha in Asia. Currently, IR 64 occupies 10 million ha or about 15% of all irrigated rice land. A similar situation exists for hybrid rice. In 1998, it was reported that 95% of all hybrid rice production (nearly 17 million ha) originated from a single source of cytoplasmic male sterility, i.e., the wild abortive (WA) source (Brar, et al., 1998). The genetic uniformity of modern rice varieties and hybrids results in the crop being highly vulnerable to outbreaks of numerous pests and diseases.
There is also concern that the spread of high-yielding varieties, with limited genetic diversity, erodes the diversity of rice. Few traditional varieties are currently cultivated and many may be lost as farmers adopt improved material. There is also evidence that out-crossing of improved varieties erodes genetic diversity (Ellstrand, 2001). The loss of genetic diversity is a consequence of agriculture advancement, but it can be argued that the contribution to world food security from the use of high yielding varieties far surpasses the potential value of relying on traditional germplasm.
It is surprising that a breeding program operating out of the Philippines can identify genotypes that are superior to many national programs that are working within the local production ecology. This can be interpreted that many national breeding programs have not advanced to the stage that they can effectively utilize introduced breeding lines to cross into local material but instead are dependent upon introduced material for new varieties. The end result of this deficiency is widespread adoption of elite breeding material from a single source and subsequent genetic uniformity. The apparent weakness of national breeding program has serious implications for promoting more advanced technologies such as hybrid rice and transgenic material. The problem of genetic uniformity is not limited to developing countries. US rice is notorious for a narrow genetic base; nearly all production in Australia utilizes the same variety widely used in California. Latin America rice production is also built upon a narrow genetic base (Cuevas, et al., 1992).
The relatively low nutritional quality of rice is a concern, especially in areas where rice consumption is very high. Rice is the main source of energy and is an important source of protein providing substantial amounts of the recommended nutrient uptake of zinc and niacin (Table 4). However, rice is very low in calcium, iron, thiamin and riboflavin and nearly devoid of beta-carotene. There appears to be some genetic variation for iron and zinc content in rice, which may offer an opportunity for improving the nutritional value of rice for these minerals. The Golden Rice, current vitamin A-enrich rice could contribute to alleviating Vitamin A deficiency in the future.
There will be limited potential for expanding area under production due to increasing competition for land and water from industrialization and urbanization. Irrigated rice is cultivated annually on approximately 75 million ha or about half of the total area planted to rice. However, due to its high productivity, irrigated rice is responsible for approximately 75% of total rice production. The difficulty with irrigated rice is its luxurious consumption of water, which surpasses the need of the crop. In Asia, irrigated rice consumes 150 billion m3 of water, resulting in water use efficiency of approximately 20,000 m3/ha. Assuming an average yield of 5 tonnes/ha, the water productivity of irrigated rice is only 0.15 kg of milled rice/m3of water. Currently, the price of milled rice on the international market is approximately US$250/tonnes, resulting in a water productivity of only US$0.038/m3. The low productivity of irrigated rice makes the crop non-competitive with other uses of water.
It has been estimated that a small decrease of 10% in the water use for irrigated rice would save approximately 150,000 million m3, which is equivalent to approximately one-fourth of all the fresh water used world-wide for non-agricultural activities (Klemm, 1999). Numerous studies have shown that irrigated rice can be easily cultivated using 8 - 10,000 m3/ha, which is approximately 50% of current use, without affecting yield. The major difficulty with conserving water is that it (the water) is not priced properly. Most irrigation schemes charge the user by area, provided there is a charge, and not volume of water consumed. With this system, there is no economic incentive to conserve water.
There are other proposals for reducing irrigated rice water consumption, including limiting rice cultivation to only the rainy season, more water efficient varieties (C4 type plants), promotion of upland rice and use of biotechnology tools to induce drought tolerance into rice (Tuong and Bouman, 2002). All of these alternatives have a cost. Irrigated rice is most productive during the dry season, little genetic variation exists with rice for water use (rice is a semi-aquatic plant) and upland rice provides low and unstable yields. Introducing C4 -type of photosynthesis addresses only a small portion of the overall water use in irrigated rice production.
However, much can be done by simple conservation; that is, maintaining only supersaturated soil conditions during cultivation of the crop, elimination or severely reducing land preparation in water (puddling) and maintaining water within the field by reducing discharges. In addition, more efficient delivery systems that reduce conveyance losses are required. Good weed management must be part of this strategy. Improved efficiencies in rice production are urgently required in order to compete with alternative uses of these resources.
Agricultural activity is the main user and abuser of natural resources. There is worldwide pressure for more benign agriculture activities. Future production will be under public scrutiny and pressure to comply with the several international agreements; in particular the World Trade Organization's Agreement on Agriculture and the UN Framework Convention on Climate Change. Irrigated rice production is particularly vulnerable to emerging environmental regulations due to the excessive use of irrigation water, indiscriminate use of pesticides and inefficient use of fertilizers. Rice is highly suspect of contributing to large amounts of carbon dioxide, methane, nitrous oxide and ammonia emissions. Carbon dioxide is emitted during burning of crop residue. This is a standard practice in much of the world. Environmental regulations in California limit the burning of rice straw to only 25% of the cultivated area per year. However, most countries have not developed regulations regarding burning of crop residue but may be compelled to do so by international trade agreements.
Recently the debate in the international community has shifted from carbon dioxide to more potent gases. Methane emission is peculiar to irrigated rice due to the long periods of flooding and the anaerobic decomposition of incorporated organic matter (Hou, et al, 2000). It is estimated that irrigated rice accounts for 20% of the global emission of methane. Methane is approximately 20-fold more potent as a greenhouse gas as compared to carbon dioxide. Approximately 90% of the methane emissions are emitted via the plant, and there are reports of genetic differences in rice in emitting methane (Wang, et al., 1997). Although little information is available from field studies concerning cultural practices and methane emissions from rice, it would appear to be feasible to reduce methane by short dry fallow or rotation with an upland crop to permit organic matter to be decomposed under aerobic conditions before subjecting the soil to anaerobic conditions for irrigated rice cultivation.
Nitrous oxide is derived mainly from mineral nitrogen fertilizer (Mosier, et al., 1996). In irrigated rice, much nitrous oxide can be emitted when soils are permitted to dry after application of urea and subsequently flooded. Continuous water maintenance after applications of urea fertilizer on dry soil can significantly reduce nitrous oxide emissions. Ammonia is also derived from mineral nitrogen fertilizer. Approximately one-sixth of global emission of ammonia is attributed to fertilizer use in crop production (Bouwman, et al. 1997). In irrigated rice, ammonia emission is principally a result of inefficient use of urea. The principal problem is the application of urea in water or on mud results in approximately 70% of the urea volatilizing as ammonia. This rate can be reduced by at least 30 - 50% without affecting yield by efficient but simple methods of N fertilizer management.
Historically most governments in the major rice producing and consuming countries developed policies that maintain stable paddy price for consumers in urban centers and provide subsidies to rice farmers. These policies led to a continuous expansion of rice production and held market prices within the purchasing power of low-income consumers. In countries that are major rice exporters, policies favored the export market; albeit, often at the expense of the producers. The current world prices are the lowest in several decades. Exports from Thailand, the world's biggest exporter, reached a record in 2001/02, even though premium quality white rices sold for only US$ 178/tonnes. This is possible only because of strong government support in Thailand. Global depression in rice prices is also a concern in Latin America where several governments have instituted trade barriers to protect national production. In the U.S. and Western Europe, rice is one of the most highly subsidized crops, resulting in huge government expenditures to support rice growers. These governmental supports, however, are expensive. Also, policies to support the rice sector are limited by commitments under the Uruguay Round on Agriculture and structural adjustment programs. Consequently, sustainable rice production in the longer terms would require improvement in production efficiency.
Finally, there are a plethora of institutional and policy factors that will require significant changes if future needs are to be fulfilled. There will be an increased need for technical assistance in order for farmers to adopt more efficient practices. Where public sector-supported technology transfer programs and other support services suffer from institutional inertia and are inefficient and ineffective, new paradigms are required for providing and financing support services, assisting in technology transfer and improving processing and marketing.
Development and arising issues in rice industry sector and science, on the other hand , offer opportunities, if properly harnessed would lead to sustainable production. The urbanization offers new approaches to rice marketing and increased incomes increased demand for quality rice; thus providing opportunities for market-driven rice based production systems. Biotechnological tools and other advanced breeding methods could help to generate rice varieties with higher yielding potential, more tolerant and/or resistant to biological and a-biological stresses, and more nutritive. Holistic and integrated crop management systems increase yield, reduce cost and environmental degradation through increasing the efficiency of rice growing activities. Higher income from rice production could be realized with the reduction of losses during harvest and post-harvest operations as well as the diversification of intensive rice-rice system.
Increasing the genetic yield potential of rice has been proposed by IRRI as a means for stimulating yields and this belief has lead to the efforts into or "New Plant Types" (NPT). This concept was first developed in the early 1990s based upon crop modeling with the stated goal of identifying NPTs with yield potential of 12-15 toones/ha by the year 2002 (Fisher, 1994; Peng, et al., 1994). Progress with NPTs has been slow.
Hybrid rice is the most significant technology since the identification of dwarf plant-types. Hybrids have consistently shown a 15 -20 % increase in yield compared to conventionally bred varieties. Scientists in China initiated hybrid rice breeding efforts in the late 1960s and the first commercial hybrid was introduced in 1974. In year 2000, it was estimated that hybrid rice was cultivated on approximately 16 million hectares in China; 300,000 ha in Vietnam; 150,000 ha in India and 30,000 ha in Bangladesh (IRRI, 2000). There are also minor plantings of hybrids in Korea DPR, Myanmar and the Philippines. A commercial company in the US has also been active in hybrid research, with the objective of identifying hybrids suitable for production in the temperate regions of the Americas, i.e., southern US, southern Brazil, Uruguay and Argentina. Currently, almost all production is based upon three-line hybrid varieties. China has recently promoted two-line hybrids and in 2001, these hybrids covered approximately 2 million ha (communication with Prof. Yuan Longping, 2001).
In spite of these advances, there are several factors that have tempered the widespread adoption of hybrids. Seed production is the most formidable obstacle to the spread of hybrids. F1 seed production in China was reported to be only 0.41 tonnes/ha in 1976 but technological advances increased the seed yield to 2.5 tonnes/ha in 1995 (Yuan and Fu, 1995). Chinese scientists reported higher F1 seed yields (2.5 - 3 tonnes/ha) from the two-line system. However, outside China, yield of F1 seed production is still low. In both Vietnam and India, F1 seed yields were reported to be only 1.3 - 1.7 tonnes/ha (Quach, 1997, Ahmed, 1997) resulting in higher prices of hybrid seed, thus high costs of commercial hybrid rice cultivation. Consequently hybrid adoption is still limited to areas where labour wages are low and transplanting is practiced. The persistent low yield of hybrid seed production outside China, regardless of considerable investment and efforts by FAO, UNDP, IRRI, AsDB and National Research Systems during the 1990s (Nguyen, 2000) suggest that the wide adoption of hybrid rice outside China still needs the indetification of or the breeding for CMS lines with high ability to maintain the pollen sterility and high out-crossing rate.
In summary, efforts to increase yield by raising the yield-barrier with NPTs or hybrid rice are still hindered by inherent technological difficulties. The biotechnological tools and methodologies could provide solution to these difficulties. The most important achievement in rice biotechnology is the sequencing and mapping of rice genome which has been carried out by the International Rice Genome Sequencing Project (IRGSP) and other public and private institutions. Knowledge on rice genome could effectively assist the breeding of new rice varieties, including the transfer of genes from other crops/organisms to rice.
Currently, there is only one reported variety of rice in commercial production that has been developed using transgenic procedures. However, there are several reports of material in the testing stage. Most involve herbicide resistant and/or use of the Bt gene. Additionally, herbicide resistant mutants will soon be released. The use of genetic modified organism (GMOs) is still highly controversial, but new traits important for consumers and producers will likely be available in the forthcoming decade. Rice producing countries will have to decide on how and to what degree these innovations will be adopted. Biosafety analysis is important, but this is not uniquely a GMO-related consideration.
Most existing high yielding varieties have genetic yield potentials of approximately 10 tonnes/ha. Under excellent management in farmers' field these varieties frequently produce 7-8 tonnes/ha, but average yield by producers is about half this amount. The last session of the IRC recommended FAO to undertake a careful analysis of this yield gap. In September 2000, FAO organized the Expert Consultation on the Yield Gap and Productivity Decline in Rice Production (FAO, 2000). Numerous results from on-farm field studies showed that the yield gap in the developing world was approximately 46% or equivalent to approximately 2.7 tonnes/ha (Table 5). The yield gap is most apparent in the irrigated ecology since the production environment is more suitable for high yields, most growers are already using improved genotypes and much technology exists for irrigated rice production. An increase in production of approximately 130 million tonnes of milled rice could be achieved by bridging the yield gap in the irrigated rice areas of Asia -- which encompasses 72 million hectares. Narrowing the yield gap in irrigated rice, therefore, merits major attention.
The gap results from numerous deficiencies due principally to inadequate crop management practices. Improved crop management technologies are available but many have not been introduced, tested and modified to suit local conditions. Deficiencies in crop management, therefore, are often the result of inadequate technology transfer. Most technology transfer efforts are provided by public sector entities that have limited funding, inadequately trained staff and little incentive for improvement. Furthermore, many extension agencies suffer from institutional inertia. New approaches to technology transfer are essential.
There are examples of innovative means of providing services to growers without massive public sector support. Rice producer associations in Latin America have organized themselves into FLAR (or Latin American Fund for Irrigated Rice) with established collaborative programs that are international in scope to work on common problems thereby avoiding duplication of efforts and facilitating information exchange. In Australia, the RiceCheck technology transfer program has been highly successful in increasing national yields by bridging the yield gap (Clampett, 2000).
There are important differences between "knowledge" and "seed" based technologies. Improved features incorporated into the genes of an elite cultivar are relatively fixed and visually evident and farmers can easily distinguish between disease resistant and susceptible varieties and other improved phenotypic traits. Additionally, once growers accept seed based technologies, they can continue using it without further assistance and costs unless it is based on hybrids. In contrast, it is often difficult for growers to see the impact of improved water management that significantly reduces water usage. Similarly, farmers rarely understand the need to maintain a biological equilibrium for pest management. Farmers can observe the response to N fertilizer but not large losses that occur via volatilization due to inappropriate applications.
Limitations in crop management do not exist in isolation but are interlinked. For example, increased seedling vigor from the use of high quality seeds will not affect yield if the crop is inadequately fertilized. Similarly, the crop cannot respond to improve fertility if weeds are permitted to compete. It is also very difficult to obtain high fertilizer efficiency without proper water management. These examples illustrate the importance of developing an integrated approach. However, many of these limitations are often addressed as single issues, resulting in programs such as Integrated Nutrient Management, Integrated Pest Management, and Integrated Water Management. When crop management constraints are integrated into a unified technology transfer program rapid progress can be made. The integrated Ricecheck program in Australia addresses 10 key management factors in a holistic fashion. This integrated program was instrumental in increasing the country average yield from 6.5 tonnes/ha during the 1980s to 8.9 tonnes/ha in the late 1990s. During this period the yield gap was reduced from 45 to 33 %. This accomplishment illustrates the benefits that can be derived from an integrated approach and an innovative extension service (Clampett, 2000).
This program is a decision-making process in which a series of limitations to production have been identified and integrated into a production program. For the Australian conditions the critical management practices include crop establishment, times of planting, N management, weed control, and water management. Farmers are encouraged to follow best management practices based upon "critical checks" that are known to have major impacts on yield. In addition to the development of the "critical checks" concept, the approach to technology transfer is unique and is based upon establishing farmer groups that not only accelerate technology transfer but also serve as a feed-back mechanism for researchers and extension workers.
Improved N management provides another good example of the need for an integrated approach to crop management. In the transplanting system, such as practiced in most of Asia, N management is particularly difficult since the land is prepared in water, the crop is seeded in mud and humid conditions prevail throughout crop development. Application of urea, the most prevalent source of N fertilizer, in water or moist soil results in large losses, normally 70 - 80% of the N applied. These losses produce low N efficiency, usually in the range of 5 - 15 kg of grain/kg of N (Table 6) and contribute significantly to greenhouse gas emissions such as nitrous oxide and ammonia. Recent studies by FLAR in Columbia demonstrate the merit of incorporating N in dry soil prior to planting; N losses were only 20 - 30% with efficiencies of 25 - 30 kg of grain/kg of N (FLAR, 2001). These studies clearly illustrate that N efficiency can be increased 3-fold without additional costs, simply by timely applications, under conditions that reduce losses (dry soil) followed by adequate water and weed management.
Higher yields will only lead to additional production if accompanied by improvements in post-harvest operation. Post-harvesting handling of rice in much of Asia has not improved for decades. Hand harvesting and threshing are common, rudimentary grain drying prevails, and rice is poorly stored. Results from surveys conducted by FAO show losses from these operations amount to 10 -37% of the total harvest (Table 7). There is much technology available for reducing these losses to more acceptable levels.
Losses from improper drying are high in much of Asia. Sun drying is the most common method and provides little control over the rate of drying. Much of the grain is either dried in the field in windrows or spread out on surfaces (roadsides) after threshing. Lack of control of moisture loss during drying results in fissured grain that breaks during milling. Additional losses in the milling process are caused by inadequate technical performance of milling equipment. For example, the popular Engleberg type's single pass mill is notorious for breaking grain during milling and milling yields are often only 50%, as compared to milling yields of 70% with modern milling equipment.
Normally the price ratio of intact or ¾ grain to broken grain is 3:1. Consequently, high grain breakage represents large financial losses. For decades most Asian countries were concerned with rice self-sufficiency and limited attention was given to quality. However, in recent years consumer purchasing power has increased and quality rice is preferred. Additionally, the export market demands high quality rice. Improving milling yields and reducing breakage are factors readily amendable but require major private sector investments.
Besides improving the drying process, there are also other technologies for reducing milling losses. A new genetic trait labeled "tolerance to delayed harvest" permits grain to dry in the field to low levels (19%), thereby allowing flexibility in harvesting without inducing losses due to breakage during milling (Berrio, et al, 2002). Tolerance to delayed harvesting has been found in two US commercial varieties and several sources have been identified in tropical and temperate regions of Latin American. Tolerance to delayed harvesting is becoming a major breeding objective in Latin American. This genetic trait has not been used in Asian breeding programs but could be a valuable trait.
The intensive cultivation of irrigated rice has been advocated as a means of increasing production per unit area to meet food security. Many countries promoted early varieties in the 1980s to facilitate three rice crops per year. However, rice is a labour-intensive crop in much of Asia. Labour requirements in five major rice producing countries range from 243 person-days/ha in Bangladesh, 195 in India, 156 in Indonesia and 60 - 80 in the more mechanized production systems of the Philippines and Thailand (Pingali, et al., 1997). Combining information on average yields in these areas with government support prices and labour requirements permits a gross estimate of the return-to-labour. In India, the return-to-labour is estimated at US$ 1.53/day, in Bangladesh $2.57/day, Thailand $6.06/day, Indonesia $5.58/day and Philippines $7.28/day (Table 8). Such low returns-to-labor are feasible only when there are no alternative means of employment.
The returns-to-labour are directly related to yield. Improvements in yield combined with greater production efficiency increases the returns-to-labour. One of the primary benefits from narrowing the yield gap would be greater return-to-labour. Recently, due to adequate national rice production and restrictions on irrigation water, several countries are currently discouraging intensive rice cultivation. Also, markets for more highly lucrative crops such as vegetables offer opportunity for increasing farmers' incomes. Crop diversification within the irrigated rice system is often advocated as a means to stabilize rice yields, to reduce methane emission and to increase farmers' incomes. In many cases, diversification is hindered by the lack of suitable crops that can produce on heavy, ill-drained rice lands, especially during the rainy season. Crop diversification requires more attention but efforts need to focus on identifying alternative crops suitable for heavy soils that can be marketed.
There are several practices for reducing intensive labour use in rice, such as direct seeding to avoid the laborious task of transplanting. Direct seeding is the standard means for crop establishment in the Americas; consequently, the technology (know-how) for direct seeding is readily available. Much technology for reducing other labourious practices is also available but must be adjusted to local conditions. Farm labour is a major source of employment in several Asian and African countries so any attempt to reduce labour must be in balance with social concerns, especially as related to rural employment.
An overview of the current rice situation indicates that the situation is much more positive than frequently reported. The most concerning issue is low rice prices in the international market that could have a depressing affect on production in Asia if this situation continues. However, several countries have taken advantage of the poor economic returns on rice cultivation and are adjusting production accordingly. China is decreasing the area under cultivation and also discouraging intensive cultivation. Vietnam is also reducing support to rice production. Most counties are working within the framework of international trade agreements but also providing significant support to rice prices because there is a strong linkage between rural poverty and rice production in many Asian countries. It is unclear how long many of the countries can continue to provide the required support due to the huge financial costs involved.
The hysteria of a pending rice crisis does not appear to be justified. Future rice needs may not be as great as reported due to declining consumption in several Asian countries, especially China. However, meeting future rice demands will be a challenge. Yield stagnation in the more favored irrigated production ecology is the principal limitation to increased production. There are several potential mechanism for addressing yield stagnation, including narrowing the yield gap of current varieties and identification of higher-yielding genetic material, i.e., hybrid rice, NPTs and perhaps the new NERICA for Africa. Regardless of the approach, improved crop management practices will be required in order for varieties or hybrids to express more of their yield potential. The most appropriate means of addressing rice needs in the immediate (10 years) term is by bridging the yield gap in irrigated rice. Production from the irrigated sector, which accounts for 75% of global production, can be increased by 45% by improving crop management. Much of the technology for narrowing the yield gap is available. Weak technology transfer programs is the limiting factor for reducing the yield gap.
Significant progress can also be made in increasing rice output by reducing post-harvest and milling losses. Milling losses are significant and require upgrading of the milling operations. There is an increasing demand for better quality rice and this should provide a stimulus for upgrading the milling infrastructure in several Asian countries.
Fig. 1. Recent worldwide trends in rice production, consumption, and ending stocks (Source of data: USDA, Food Crop Database, 2002).
Table 1. Current and estimated rice production (milled) in year 2010, current and 2010 estimates of per capita, annual growth rates of production and per capita consumption between 2000-2010 and projected trade trends of rice (milled).
|PRODUCTION||PER CAPITA CONSUMPTION||TRADE1|
|LATIN AMERICAN & CARIBBEAN||13.9||17.1||1.8||27.9||28.5||0.17||-1.4||-0.9|
1 Trade Data: - = import, + = export. Trade data for World is total exchange. 2Others=Transitional Eastern Europe, CIS and Baltic countries. Source: FAO, Commodities and Trade Division, 2002.
Table 2. Projections of world rice demands for human food in years 2015 and 2030 and growth rates in demand (%/year), taking into account current estimates of GDP growth, emerging consumption patterns, population trends and other variables, such as urbanization.
|Rice Demand, million MT (milled)||Per capita Growth in Demand, %/year|
|Rice as Food, kg per capita|
|- East Asia||106||100||96|
|- E, Asia, excluding China||132||129||124|
|- South Asia||79||84||81|
Source: FAO (forthcoming), "World Agriculture: Towards 2015/30, an FAO Study", Rome
Table 3. Population and GDP projections for the periods of 2015 and 2030.
|Population, million||Annual Population
Growth Rate, %
|Total GDP Growth
|Per capita GDP
|1997/99||2015||2030||1997/99- 2015||2015- 2030||1997/99- 2015||2015-20310||1997/99- 2015||2015-20310|
|Near East/North Africa||377||520||651||1.9||1.5||3.7||3.9||1.8||2.4|
Source: FAO (forthcoming), "World Agriculture: Towards 2015/30, an FAO Study", Rome.
Table 4. Nutritional aspects of rice consumption in selected countries of the world.
|g/day||% of Recommended Daily Intake|
Source: Kenny, Gina. 2001. FAO. ESNA Consultant. Report "Nutrient Impact Assessment of Rice in Major Rice Consuming Countries.
Table 5. Estimates of the yield gap in irrigated rice in selected countries.
|COUNTRY||Improved Yield||Farmers' Yield||Yield Gap||% Yield Gap|
|IRRI - 9 countries||8.2||3.7||4.5||55|
Sources: Information extracted from Proceedings of the Expert Consultation on the Yield Gap and Productivity Decline in Rice Production, September 2000.
Table 6. Mean N fertilizer rate and N fertilizer efficiency in five Asia countries.
|SITE/COUNTRY||N FERTILIZER RATE||N FERTILIZER EFFICIENCY|
|Kg N/ha||Kg grain/kg of N|
|Mekong Delta, Vietnam||46||8.6|
|Central Luzon, Philippines||136||12.5|
|Northwest Java, Indonesia||108||5.3|
|Central Flood Plains, Thailand||114||11.4|
|Tamil Nadu, India||115||15.3|
Source: Olk, D.C., K.G. Cassman, G. Simbahan, P.C. Sta. Cruz, S. Abdulrachman, R. Nagarajan, Pham Sy Tan and S. Satawathananont. 1996. Congruence of N fertilizer management by farmers and soil N supply in tropical irrigated low rice systems. IN: Proceedings of the International Symposium on Maximizing Sustainable Rice Yields Through Improved Soil and Environmental Management. Nov. 1996. Khon Kaen, Thailand.
Table 7. Estimates of losses in Southeast Asia during various stages from harvest to processing.
RANGE OF LOSSES, %
|HARVEST||1 - 3|
|HANDLING IN THE FIELD||2 - 7|
|THRESHING||2 - 6|
|DRYING||1 - 5|
|STORAGE||2 - 6|
|TRANSPORT||2 - 10|
10 - 37
Source: FAO. 2000. Information Network on Post-Harvest Operations. Information extracted from DeLucia and Assennato. 1994. FAO Agriculture Services Bulletin No. 93.
Table 8. Estimates of gross returns on labor in irrigated rice in selected Asian countries
|Price of Rice2
|Return on Labor4
Source: 1Pingali, P.L., M. Hossain and R.V. Gerpacio. 1997. Asian Rice Bowls: The Returning Crisis. IRRI. 2Government support rice from Review of Basic Food Policies. Commodities and Trade Division. FAO. 2001. 3Average irrigated yield extracted from IRRI, 1993. 4Assuming material inputs (fertilizer, pesticides and etc) amount to US$120/ha, based upon studies in the Philippines, extracted from Pingali, P.L. et al, 1997).