1. INTRODUCTION
Rice is the staple food of Asia and part of the Pacific. Over90 percent of the worlds rice is produced and consumed in the Asia-PacificRegion. With growing prosperity and urbanization, per capita rice consumptionhas started declining in the middle and high-income Asian countries like theRepublic of Korea and Japan. But, nearly a fourth of the Asian population isstill poor and has considerable unmet demand for rice. It is in these countriesthat rice consumption will grow faster. The Asian population is growing at 1.8percent per year at present, and population may not stabilize before the middleof the next century. A population projection made for the year 2025 shows anaverage increase of 51 percent, and in certain cases up to 87 percent over thebase year 1995. So far the annual growth rate for rice consumption in theAsia-Pacific Region over a period of 45 years (1950 to 1995) has kept pace withthe demand, more through yield increase rather than area expansion. Improvedvarieties have made a significant impact (Khush, 1995) in an ever increasingorder during this period. The world rice supply has more than doubled from 261million tonnes in 1950 (with Asian production of 240 million tonnes) to 573million tonnes in 1997 (including the regions production of 524 milliontonnes). Production has more than doubled overtaking the population growth ofnearly 1.6 times in Asia. A measure of this success is reflected by the fall inthe price of rice in the world markets.
The Asia-Pacific Region, where more than 56 percent of theworlds population live, adds 51 million more rice consumers annually. As aresult of this the thin line of rice self-sufficiency experienced by manycountries is disappearing fast. How the current 524 million tonnes of riceproduced annually will be increased to 700 million tonnes by the year 2025 usingless land, less people, less water and fewer pesticides, is a big question. Thetask of increasing substantially the current level of production will faceadditional difficulties as the avenues for putting more area under modernvarieties and using more fertilizers for closing the yield gap, bringing inadditional area under rice or under irrigation are becoming limited. Theirrigated rice area currently occupies about 56 percent of the total area andcontributes 76 percent of the total production. It would be hard to increasethis area due to the problems of soil salinity, high cost of development, waterscarcity, alternative and competing uses of water, and environmental concerns.Thus, increased productivity on a time scale has to make the major contributionacross ecosystems by using more advanced technologies.
2. CURRENT RICE SITUATION
2.1 Production-Consumption Scenario
Rice is the crop of the Asia-Pacific Region. The projecteddemand by the year 2025 is mind boggling (Hossain, 1995), as in major Asiancountries rice consumption will increase faster than the population growth. Insummary, in Asia, the rice consumption by the year 2025, over the base year1995, will increase by more than 51 percent (Table 1). Another significantchange will be the development of many mega cities of the size of 10-15 millionpeople over and above the general urbanization of the populace. Thus, the numberof consumers will grow and the number of producers will be reduced dramatically.The current demand of 524 million tonnes is expected to increase to over 700million tonnes. Rice will continue to supply 50-80 percent of the dailycalories, and thus the average growth rate in production has to keep pace withthe growth rate of the population.
Table 1. Projections of Population in Major RiceProducing and Consuming Countries in Asia, 1995 to 2025
| Country | Population | Annual Growth Rate | Projected | Percent | |
| 1995-2000 | 2020-2025 | ||||
| China | 1199 | 0.9 | 0.5 | 1471 | 23 |
| 934 | 1.7 | 1.0 | 1370 | 47 | |
| Indonesia | 192 | 1.4 | 0.8 | 265 | 38 |
| Bangladesh | 121 | 1.8 | 1.1 | 182 | 50 |
| Vietnam | 74.1 | 2.0 | 1.2 | 117 | 58 |
| Thailand | 60.5 | 1.3 | 0.7 | 80.8 | 34 |
| Myanmar | 46.8 | 2.1 | 1.1 | 72.9 | 56 |
| Japan | 125 | 0.3 | -0.3 | 124 | -1 |
| 69.2 | 2.2 | 1.2 | 115 | 66 | |
| Rep. of Korea | 44.8 | 0.8 | 0.3 | 52.9 | 18 |
| Pakistan | 130 | 2.7 | 1.6 | 243 | 87 |
| Asia (excluding China) | 2244 | 1.8 | 1.1 | 3389 | 51 |
Source: World Bank Population Projections, 1994-95EditionDuring 1997 the Region produced 91.37 percent of theworlds rice during the decade 1987-1997, with an average annual growthrate of 1.8 percent. In the last 3 decades, starting with the era of the greenrevolution triggered by IR 8, rice production in Asia increased by more than 100percent outstripping the population growth of 80 percent. This increased theavailability of rice and decreased the price, which fully justified theinvestments in research, thus creating a sense of social justice. Severalcountries like Cambodia, China, India, Indonesia and the Philippines achievedself-sufficiency, even though short-lived in some. Liberalization of economies,increasing consumer wealth and the proliferation of grey-channel trade ignitedthe demand for high quality rice imports. Chinas imports are increasingsteadily (Anon. 1998). In addition to Thailand, countries like Australia, India,Myanmar, Pakistan, Sri Lanka and Vietnam became rice exporters. During the year1995, together they exported 17.1 million tonnes of rice (FAO, 1997) whichaccounted for 73.4 percent of the total world export in rice. The rice exportgrew during the 1985-1995 period by an average annual growth rate of 6.1 percent(FAO, 1997). This has been possible even in the light of the fact that the majorproducers like China increased their imports by an annual growth rate of 2.4percent during this period. However, the number of rice farmers has beendeclining faster in proportion to the development stage of the countries, (4.3percent on average in the Asia-Pacific Region). In addition, growth rate infertilizer usage has leveled off in general and use of modern varieties is alsoplateauing with major producers. There has been almost no growth (0.4 percent)in the rice area but the production (1.8 percent) has grown due to the growth inthe productivity (1.4 percent on annual basis) during the period of 1987-1997.In some countries like Bangladesh, Bhutan, China, DPR Korea, Fiji, and theRepublic of Korea, the rice area decreased during this period.
2.2 Rice Balance in the Region
Aggregate rice output growth rate for Asia increased from 2.2percent per annum during 1950-1965 to 2.9 percent during the 1965-1980 period,outstripping the annual population growth of 2.23 percent. This growth declinedto 2.6 percent during 1980-1990 and to 1.8 percent during the 1987-1997 period.Despite an anticipated decline in per capita rice consumption, aggregate demandfor rice is expected to increase by about 50 percent during 1990-2025. As incomegrows, per capita rice consumption is expected to decline as consumerssubstitute rice with high-cost quality food containing more protein and vitaminssuch as processed preparations of rice, vegetables, bread, fish and meat. Japanand the Republic of Korea have already made this transition, and rest of theAsia will be making it in proportion to the pace of their economic growth. Butthese declines will be offset by the population growth (Table 1) and additionalincome (Table 2), increasing the net demand of rice to over 700 million tonnesby 2025. It is frightening to note that the rice production growth rate of1975-85 (3.2 percent) which declined to 1.8 percent during 1987-97 (Table 3) isdeclining further. As a result in the next 10 to 20 years most Asian countrieswill find it hard to be self-sufficient and in fact, helped by tradeliberalization under the General Agreement on Tariff and Trade (GATT), willlikely become net rice importers. Several countries that are now self-sufficientin rice may find it more profitable to import rice in exchange for divertingproduction resources to more remunerative activities. But who will produce thisrice is yet another issue to be understood and answered.
Table 2. The Demand Response to Incomes and Prices forRice (Estimates for Selected Asian Countries)
| Country | Percent Increase in Demand | Percent Increase in Demand |
China | 0.09 | -0.26 |
India | 0.06 | 10.23 |
Indonesia | 0.11 | N/A. |
Bangladesh | 0.41 | -0.20 |
Thailand | 0.08 | -0.93 |
Philippines | 0.08 | -0.93 |
Japan | -0.25 | -0.17 |
Rep. of Korea | -0.11 | N/A |
Source: IRRI/IFPRI, 1995. Rice Supply and DemandProject
Table 3. Rice Production, Yield, Area and Growth Rates inProduction (P), Yield (Y) and Area (A) in the Asia-Pacific Region(1987-1997)
| Country | Production (P) | Area (A) | Yield (Y) | Growth Rate (%) | ||
| P | A | Y | ||||
| Australia | 1,352 | 164 | 8,244 | 6.2 | 4.5 | 1.6 |
| Bangladesh | 28,183 | 10,177 | 2,769 | 1.1 | -0.4 | 0.7 |
| Bhutan | 50 | 30 | 1,667 | -0.2 | 0.1 | -0.2 |
| Cambodia | 3,390 | 1,950 | 1,771 | 4.4 | 2.4 | 2.2 |
| China | 198,471 | 31,348 | 6,331 | 1.0 | -0.7 | 1.6 |
| DPR Korea | 2,347 | 611 | 3,841 | -5.1 | -1.7 | -3.3 |
| Fiji | 18 | 7 | 2,246 | -5.5 | -7.1 | 0.8 |
| India | 123,012 | 42,200 | 2,915 | 2.6 | 0.5 | 2.1 |
| Indonesia | 50,632 | 11,100 | 4,449 | 2.2 | 1.2 | 0.8 |
| Iran | 2,600 | 550 | 4,240 | 4.9 | 1.5 | 2.8 |
| Japan | 12,531 | 1,953 | 6,416 | - | -0.5 | 0.5 |
| Laos | 1,414 | 554 | 2,902 | 2.1 | - | 2.8 |
| 1,970 | 655 | 3,008 | 1.6 | 0.1 | 1.5 | |
| Myanmar | 18,900 | 6,070 | 3,064 | 4.0 | 3.3 | 0.6 |
| Nepal | 3,711 | 1,511 | 2,455 | 1.3 | 0.5 | 0.9 |
| Pakistan | 6,546 | 2,316 | 2,827 | 3.3 | 1.2 | 2.1 |
| Papua New Guinea | 1 | - | 3,023 | - | - | 0.1 |
| Philippines | 11,269 | 3,842 | 2,933 | 2.7 | 1.8 | 1.0 |
| Rep. of Korea | 7,100 | 1,045 | 6,794 | -1.8 | -2.3 | 0.5 |
| Sri Lanka | 2,610 | 660 | 3,954 | 1.3 | - | 1.3 |
| Thailand | 21,280 | 9,932 | 2,143 | 1.3 | 0.2 | 1.1 |
| Vietnam | 26,397 | 7,021 | 3,760 | 5.5 | 2.4 | 3.1 |
| Total | 523,784 | 133,696 | 3,918 | 1.8 | 0.4 | 1.4 |
| Rest of World | 49,479 | 16,115 | 3,070 | 2.0 | 0.3 | 1.7 |
| World | 573,263 | 149,811 | 3,827 | 1.8 | 0.4 | 1.4 |
Source: FAO/RAP Publication: 1998/213. BALANCE SHEET OF PROBLEMS
The task of producing the additional rice to meet the expecteddemands of the year 2025 poses a major challenge. The danger is that stabilityin rice production is linked to social and political stability of the countriesin the Asia-Pacific Region (Hossain, 1996). The scope of area expansion in somecountries is offset by the reduction in rice lands in major rice producingcountries. So far irrigated rice which occupies about 57 percent of the area andproduces 76 percent of total rice has helped double the rice production. It willbe easier to produce the necessary increases in productivity under irrigatedconditions than under rainfed or other ecosystems. The question turns moreproblematic when we think that production increases have to be realized annuallyusing less land, less people, less water and less pesticides. There areadditional difficulties of putting more area under modern varieties and usingmore fertilizers for closing the yield gap, or bringing in additional area underrice or under irrigation. The irrigated rice area would be hard to increase asthe problems of soil salinity, high cost of development, water scarcity,alternative and competing uses of water, environmental concerns of the emissionof green house gases like methane (rice fields contribute 20 percent) andnitrous oxide (fertilizer contributes 19 percent). The difficulties are furtheramplified when potential consequences of increased cropping intensity are takeninto account. Estimates of the Inter Centre Review instituted by theConsultative Group on International Agricultural Research (CGIAR) indicate thatabout 70 percent of additional production will have to come from the irrigatedrice ecosystem and almost 21 percent from rainfed lowland. To achieve this, itwas estimated that the yield ceiling of irrigated rice in Asia, for example,would need to be increased from its late 1980s level of about 10 tonnes/ha toaround 13 tonnes/ha in 2030. Simultaneously the yield gap would have to bereduced from 48 to 35 percent to produce average yields of about 8.5 tonnes/haor about double the current level. One of the several ways GATT will affectresearch will be through funding and comparative resource allocation. With themovement from subsistence to a market-oriented economy, rainfed rice productionmay bring additional changes in many countries which depend on this ecosystemheavily and have no resources to convert rainfed to irrigated systems (Pingaliet al. 1997).
3.1 Germplasm Availability and VarietalDevelopment
In the past agriculture, plant germplasm, and crop varietieswere treated differently from the industry and industrial products with respectto Intellectual Property Rights (IPR). When the UPOV convention initiated apatenting right for the plant varieties and micro-organisms in 1961 (UPOV,1991), only a few countries had become signatories. Most of the Asian countriesthat had not signed had sizeable public research investments for technologygeneration, which was seen as government support to feed the people. The IPR hasits roots embedded in World Intellectual Property Organization (WIPO)established by a convention in 1967, enforced in 1970, and attached to theUnited Nations Organization (UNO) as a specialized agency in 1974 (WIPO, 1988;WIPO, 1990). It is generally argued that IPR and patenting will assure returnsto research investment by providing product secrecy, and will attract privateinvestment for agricultural research. In GATT, there is provision for patentingalong the lines of IPR. Although, only a recommendation, it yet becomes bindingfor the signatory country to provide some alternative means of protectionfor such plants. The GATT provisions state: The only types ofinventions that countries can exclude from patentability are those whoseexploitation would prejudice public order or morality, those involvingdiagnostic, therapeutic or surgical methods for the treatment of humans oranimals, and inventions of plants and animals or essential biological processesfor their production. Countries taking advantage of this provision topreclude the grants of patents for new plants must, however, provide somealternative means of protection of such plants. In the absence of IPR andpatenting, germplasm moved unrestrictedly and made contributions globally(Chaudhary, 1996), which can no longer be tolerated.
The historic discovery of the semi-dwarfing gene (sd1) ofDe-Geo-Woo-Gen variety in the district of Taichung in Taiwan ROC(province of China), revolutionized rice production in the world. Todayvarieties carrying this gene are cultivated in almost all the tropical ricegrowing countries. Can one imagine if the world has to pay Taiwan for this gene?Grassy stunt virus during the 1980s threatened the cultivation of ricegrown without the use of costly and hazardous pesticides. A single accession ofOryza nivara had the requisite gene later named as gsv. Eversince, all the IR varieties starting from IR 28 incorporating this gene weredeveloped and released. Dr. G. S. Khush (personal communication) mentionsthat at its peak a single variety IR 36 carrying gsv gene was planted in11 million ha in the 1980s. IR 64, another variety carrying gsvgene is planted in about 8 million ha. There is no fair estimate available ofthe area under gsv gene but a rough guess is that in Asia alone it willbe more than 100 million ha. One can very well imagine the production impact ofa single freely available gene simply taken from a rice producing area in theeastern part of Uttar Pradesh in India. Can one imagine if this gene waspatented by a private company? What if the world has to pay for this gene to thecommunity from where the accession carrying this gene was collected?
3.2 Stagnation, Deceleration and Decline ofProductivity
Yield decline is noticed when in order to get the same yieldlevel, increased amounts of inputs are needed. This trend has been felt byfarmers in irrigated rice systems, and reported by Cassman et al. (1997). Yielddecline may occur when management practices are held constant on intensiveirrigated rice systems, owing to changes in soil properties and impropernutrient balance. It also leads to a depletion of soil fertility when inputs donot replenish extracted nutrients. The need for designing regional programmes ofaction to enhance and sustain rice production and to attain durable foodsecurity and environmental protection in the Asia-Pacific Region was alsorecommended by an earlier FAO Expert Consultation (FAO, 1996). It wasrecommended that different countries should undertake systematic studies on theactual and potential downward yield trends (deceleration, stagnation, anddecline), quantify these processes and delineate the affected areas asaccurately as possible. These could find a place in the research agenda of theCGIAR institutions like IRRI, WARDA and other centres. The development of morelocation specific technologies for crop management, Integrated Pest Management,Integrated Nutrient Management, technology transfer to further reduce the yieldgap, and manpower development in appropriate areas would have to be handled byNARS. The sharing, testing and utilization of technology and knowledge acrossnational boundaries have to be facilitated by the CGIAR institutions and FAOthrough various networks supported by them (Tran, 1996). FAOs work onagro-ecological zones (AEZs) and the CGIARs Eco-Regional approach havelots of common ground for this new paradigm in technology assessment andtransfer.
3.3 Declining Production Resources
Rice land is shrinking owing to industrialization,urbanization, crop diversification and other economic factors. Under thesepressures in China, the rice area declined from 37 million ha in 1976 to 31million ha in 1996. A similar trend of negative growth is visible in manycountries even over a relatively shorter period from 1986-1996 (Table 3).Similarly, the number of rice farmers is also declining fast in most countries.In the Republic of Korea during 1965-95, the numbers of rice farmers declined by67.3 percent. It is estimated that by the year 2025, more than 50 percent ofpeople will live in urban areas compared to 30 percent in 1990. Growingurbanization and industrialization will further reduce the agricultural labour,increase the labour wages and farm size, needing more mechanization.
The Green Revolution technologies used in irrigated andfavourable rainfed lowlands, which stabilized rice production and reducedprices, are almost exhausted for any further productivity gains (Cassman, 1994).In fact, a net decline in the irrigated area may be expected if problems ofsalinization, waterlogging, and intensification-induced degradation of soil isnot handled forthwith. It is predicted that quality and quantity of water foragriculture will be reduced. Water will become scarce and costly for agriculture(Gleick, 1993) and the next war may be fought over water. The water to riceratio of 5,000 litres of water to 1 kg of rice has remained unchanged over thelast 30 years, yet the availability has declined by 40 to 60 percent in Asia. Inaddition industrial and agricultural pollutants have degraded the water qualityin most countries.
3.3.1 Declining factor productivity
A significant problem in Asia is the yield decline nownoticeable in irrigated and rice-wheat rotation areas. Long-term experimentsconducted at IRRI, the Philippines, have indicated that the factor productivityhas gone down over the years. At the fixed level of fertilizer, the productivityhas been going down, and to get the same yield a higher level of fertilizer hasto be added. Cassman and Pingali (1995) concluded that decline in theproductivity is due to the degradation of the paddy resource base. They analyzedthat at any nitrogen level, the long term experiment plots at IRRI are givingsignificantly lower yields today than in the late 1960s or and early1970s. The same may hold true for farmers fields. Productivity ofrice has been declining faster in mono-crop rice areas as well as underrice-wheat rotation (Cassman et al. 1997). Sizeable areas in Bangladesh, China,India, Myanmar, Nepal, Pakistan and some in Vietnam and Thailand are underrice-wheat rotation. Thus, this problem needs attention soon without any senseof short-term complacency.
3.3.2 Deteriorating soil health
The continuous cropping of rice, either singly or incombination, has brought about a decline in soil health through nutrientdeficiencies, nutrient toxicity, salinity and overall physical deterioration ofthe soil (Cassman et al. 1997). Saline and alkaline soils cover millions ofhectares in several South and South-East Asian countries. Also upland ricecultivation has promoted soil erosion in the fields and clogged irrigation anddrainage canals down stream. The over use or improper use of irrigation withoutdrainage encouraged waterlogging, resulting in salinity build-up and othermineral toxicities. Proper technology backed by policy support and politicalwill is needed for addressing these issues.
3.3.3 Low Efficiency of Nitrogen Fertilizers
Urea is the predominant source of nitrogen (N) in the ricefields. But its actual use by the rice plant is not more than 30 percent meaningthereby that 70 percent of the applied nitrogen goes either into the air or intothe water, endangering the environment and human health. Further research isneeded to understand and avert this situation. Related to nitrogen useefficiency is the area of proper use of nitrogenous fertilizer. Use of thechlorophyll meter and leaf colour chart to improve the congruence of N supplyand crop demand is a good tool, for example, to save on fertilizer and optimizefactor productivity. However, this knowledge intensive technology has its ownhidden costs.
3.3.4 Ever-changing balance of rice and pests
Pests (including insect-pests and diseases) of rice evolvedunder the influence of host genes are changing the rice-environment. Thus,scientists are in a continuous war with ever changing races, pathotypes andbiotypes of rice pests. New and more potent genes, being added continuouslyusing conventional or biotechnological tools, fight a losing battle. But theseefforts are essential to add stability to production and avoid the recurrence ofthe great Bengal famine of the Indian sub-continent, or brown plant hoppercatastrophe of Indonesia and the Philippines, or blast and cold damageexperienced in the Republic of Korea and Japan during 1996.
3.3.5 Aging of rice farmers
The average age of rice farmers is increasing in almost everycountry in proportion to rate of its industrialization. The younger generationis moving away from agriculture in general, and backbreaking rice farming inparticular. The result is that only the old generation is staying with the ricefarming, which has manifold implications. This also raises a serioussocio-political issue.
3.3.6 Increasing cost of production
By the adoption of modern rice varieties and technologies, theunit cost of production and global rice prices came down. But since thebeginning of the 1990s, unit production costs are beginning to rise andrice farmers are facing declining profits. A stagnant yield frontier anddiminishing returns to further intensification are the primary reasons for thereversal in profitability. Contemporaneous changes in market factors -especially land, labour and water - are driving up input prices. Rapidwithdrawal of labour from the agricultural sector, diversion of land for otheragricultural and non-agricultural purposes, increased competition for water, andwithdrawal of subsidies for inputs have contributed to the current situation andmay worsen it in the future. Politically, sound lower rice prices are welcomebut who is losing?
3.4 Rice Trade and Price Incentive
Although less than 5 percent of the rice production is tradedin the international market, yet it influences the local rice prices. GATT hasincreased pressure to liberalize trade and to open up rice markets in the middleand high-income countries. It has also an indirect effect on research prioritysetting and rice production by introducing a market-oriented decision makingprocess. Though a modest expansion in rice trade can be expected due to openingof the closed markets of Japan and Republic of, yet due to a special riceclause the Philippines and Indonesia negotiated for tariff reductions. Thetariff reduction by USA and EU may lead to additional exports of specialty riceand global trade may increase in general. Subsidies at input level by individualcountries may reduce production costs marginally. The movement from subsistenceto market-oriented rainfed production may bring in additional changes (Pingaliet al., 1997). Given the long-term impact of GATT on increasing competitivenessamong ecosystems, irrigated ecosystem may get 50 percent of the research share.Issues of intensification versus diversification, yield enhancement versusquality improvement, knowledge-intensive technologies versus farmers time,private sector versus public funded research need further investigation andalignment to set research priorities (Pingali et al., 1997).
3.5 Post-Harvest Losses
It is extraordinary that the tremendous efforts being made tolift rice productivity through modifications and manipulations of the rice plantand its environment, are not matched by corresponding efforts to address thedramatic post-harvest losses of 13 to 34 percent (Chandler, 1979) that continueto occur through much of the rice growing world. Part of the productivity gainsthat have been laboriously achieved through decades of research and developmentare simply thrown away after harvest in many cases.
3.6 Weeds
Weeds reduce rice yield by competing for space, nutrients,light and water, and by serving as hosts for pests and diseases. Underfarmers conditions, weed control is not generally done properly or timely,resulting in severe yield reduction. In Asia, losses run up to 11.8 percent ofpotential production. Effective weed control requires knowledge of the names,distribution, ecology, and biology of weeds in the rice-growing regions. One oranother form of weed control has been used during the last 10,000 years (DeDatta, 1981), but no single weed-control measure gives continuous and best weedcontrol in all the situations. Various weed control methods includingcomplementary practices, hand weeding, mechanical weeding, chemical weeding,biological control, and integrated approaches are available (De Datta, 1981). Asmentioned earlier, these methods need to be fine-tuned for specific regions,ecosystems, cropping systems, and economic groups.
It is worth mentioning also that red or wild rice has become amajor problem of rice production in Malaysia, the Central Plain in Thailand andthe Mekong Delta in Vietnam where direct seeding has been increasinglypracticed.
3.7 Biotic and Abiotic Stresses
Rice has been under cultivation over thousands of years and in115 countries. As a result, it has served as a host for a number of diseases andinsect-pests, 54 in the temperate zone, and about 500 in tropical countries. Ofthe major diseases, 45 are fungal, 10 bacterial, 15 viral (Ou, 1985), and 75 areinsect-pests and nematodes. Realizing the economic losses caused by them,efforts have been directed to understand the genetic basis of resistance andsusceptibility. The studies directed to understand the host-plant interaction inrice have given rise to specialized breeding programs for resistance to diseasesand insect-pests. Ten major bacterial diseases have been identified in rice (Ou,1985). The major ones causing economic losses in any rice growing country arebacterial blight, bacterial leaf streak, and bacterial sheath rot. Many of theserious rice diseases are caused by fungi. Some of the diseases like blast,sheath blight, brown spot, narrow brown leaf spot, sheath rot and leaf scald areof economic significance in many rice growing countries of the world. Twelvevirus diseases of rice have been identified but the important ones are tungro,grassy stunt, ragged stunt, orange leaf (in Asia), hoja blanca (America), stripeand dwarf virus (in temperate Asia). Brown plant hoppers, stem borers and gallmidges are among the major insect-pests in rice production.
4. BRIGHTER RAYS OF HOPE
4.1 Raising the Yield Ceiling
The yield barrier of about 10 t/ha set by IR 8 (140 days) hasbeen broken on a per day productivity front only by the shorter durationvarieties (110 - 115 days). But to raise the yield ceiling by breaking the yieldbarrier set by IR 8, new approaches need to be implemented vigorously. Thesecould be feasible by using the concepts of hybrid rice and the New Plant Type(super rice). However, the New Plant Type is not yet available tothe farmers, and hybrid rice remains the only viable means to increase yieldpotential in rice at present.
4.1.1 New Plant Type rice
In narrowing the yield gap it is also necessary to raise theceiling of yield potential for further increase in rice yield, where applicable.The yield potential of rice is 10 t/ha under tropical conditions and 13 t/haunder temperate conditions. The present technology of hybrid rice can increasethe yield ceiling by 15-20 percent compared to the best commercial varieties.The New Plant Type of rice, which has been developed by IRRI, may raise thepresent yield potential by 25-30 percent (Khush, 1995). Rice biotechnology,which has recently made considerable progress, may also provide an opportunityto increase the rice yield in a more effective and sustainable manner.
To break the current yield potential barrier, IRRI scientistsproposed New Plant Type (NPT) rice, referred to in the media as SuperRice. The basic architecture of the plant has been redesigned to produceonly productive tillers (4-5 per plant), to optimize the allocation ofassimilates to the panicles (0.6 harvest index), to increase nutrient and watercapture by roots (vigorous roots), and thicker culm to resist lodging underheavy fertilization. Reduced tillering is thought to facilitate synchronousflowering, uniform panicle size, and efficient use of horizontal space (Janoria,1989). Low-tillering genotypes are reported to have a larger proportion ofhigh-density grains. A single semi-dominant gene controlled the low tilleringtrait, and this gene has a pleiotropic effect on culm length, culm thickness,and panicle size. The future rice plant (NPT) is also expected to have largerpanicle (200-250 grains) as compared to 100-120 of current varieties, sturdystems to bear the weight of larger panicles and heavy grain weight, and givehigh (13-15 t/ha) yields (Khush, 1995). The NPT rice will be amenable to directseeding and dense planting and, therefore, would increase land productivitysignificantly. While architecturally, the design is virtually complete, it hasnot been possible to realize the full potential (15 t/ha) of the New Plant Type.One of the principal limitations is the inability to fill all of the largenumber of 200-250 spikelets. Addressing this problem will require furtherintensive research into the physiology of photosynthesis, source - sinkrelationships, and translocation of the assimilates to the sink. Incorporationof better disease and insect-pest resistance and improvement of grain qualitywould be highly desirable, which are also being currently addressed.
4.1.2 Hybrid rice
Hybrid rice has become a reality over a period of 30 years.The rice area in China (Virmani, 1994; Yuan, 1996) under hybrid rice has reachedmore than 60 percent. Countries like India, Vietnam, Myanmar and the Philippineshave a strong interest in this direction. The Government of India has set atarget of putting 2 million ha under hybrid rice by the year 2000. All the ricehybrids grown in India, Vietnam, the Philippines, and most in China areindica hybrids. In the northern part of China, japonica hybridsare under cultivation. Now it is proven beyond doubt that indica xtropical japonica hybrids give higher yields than indica xindica hybrids. It is apparent that the next breakthrough in yield may beset in motion by the use of indica x tropical japonica andindica x NPT rice (Virmani, 1994). Currently the three-line system ofhybrid rice production is being followed. But it is known that the two-linesystem, based on the Photosensitive Genetic Male Sterility System (PGMS) or theThermosensitive Genetic Male Sterility System (TGMS) are more efficient and costeffective. NARS must re-orient their hybrid rice breeding programmesaccordingly. The one-line system using the concept of apomixis is under activeresearch at IRRI and NARS will benefit the moment any system becomesavailable.
4.1.3 Transgenic rice
Over the last two decades humanity has acquired biologicalknowledge that allows it to tamper with the very nature of creation. We are onlyat the beginning of a process that will transform our lives and societies to amuch larger extent than all inventions of the last decades. Ownership, propertyrights, and patenting are terms now linked to living matter, and tools to createthem. No global code of conduct is yet in sight. Biotechnological developments(James, 1997) are poised to complement and speed up the conventional riceimprovement approaches in many areas (Khush, 1995), which could have immediateand long term impacts on breaking the yield ceiling, stabilizing the productionand making rice nutritionally superior. In summary, the tools of geneticengineering will help to increase and stabilize rice yields under variedsituations of its growing, and thereby reducing the yield gap. These tools couldbe used to introduce superior kinds of plant resistance through widehybridization, anther culture, marker aided selection, and transformation. Thesetools, and tagging of quantitative trait loci would help enhance the yieldpotential. Rice transformation enables the introduction of single genes that canselectively perturb yield-determining factors. Approaches like differentialregulation of a foreign gene in the new host for partitioning sucrose and starchin leaves, the antisense approach as used in potato, and transposable elementsAc and Ds from maize have opened up new vistas in breaking yield barriers(Bennett et al. 1994). Identifying the physiological factors causing differencesin growth rate among rice genotypes seems fundamental to success in germplasmdevelopment for greater yield potential. Increasing the rate of biomassproduction, increasing the sink size, and decreasing the lodging susceptibilitywould enhance these efforts (Cassman, 1994).
4.1.4 Stable performing variety
Superior yielding varieties are available (Chaudhary, 1996),which can take farmers yield to 8.0 tonnes/ha if grown properly. But theirperformance is variable due to higher proportion of Genotype X Environment (G XE) interaction. G X E interaction is a variety dependent trait (Kang, 1990;Gauch, 1992; Chaudhary, 1996). While the genetic reasons of stability in theperformance may be difficult to understand, resistance to biotic and abioticstresses, and insensitivity to crop management practices are the major reasons.There is a need to identify and release stable yielding varieties even on aspecific area basis, as against relatively less stable but on a wide area basis.There are strong genotypic differences among varieties for this interaction,providing opportunities for selecting varieties which are more stable acrossenvironments and methods are available to estimate these (Kang, 1990; Gauch,1992). Thus, two varieties with similar yield may have different degrees ofstability. During the final selection process, before release, it is possible toselect varieties which are more stable and thus giving stable performance evenin poorer environments or management regimes.
4.2 Agronomic Manipulation
Other than using genetic means of raising yield ceiling,avenues of agronomic manipulation need to be explored. The success story ofBangladesh in becoming a self-sufficient country with stable yield by using Bororice instead of deepwater rice is a case in point. This is a case of matching atechnology in its proper perspectives.
4.2.1 Improving nitrogen (N) recovery efficiency,resourcing and management
Nitrogen being the major nutrient and in demand, it is appliedin every crop season. Thus, efforts in improving the N recovery-efficiency willsave quantity and cost, and reduce the cost of rice production. Avenues exist toenhance the recovery further, and also to augment its supply (Table4).
Nitrogen is the nutrient that most frequently limits riceproduction. At current levels of N use efficiency, the rice world will requireat least to double the 10 million tonnes of N fertilizer that are annually usedfor rice production. Global agriculture relies heavily on N fertilizers derivedfrom petroleum, which in turn, is vulnerable to political and economicfluctuations in the oil market. N fertilizers, therefore, are expensive inputs,costing agriculture more than US$45 billion annually (Ladha et al.,1997).
Rice suffers from a mismatch of its N demand and N supplied asfertilizer, resulting in a 50-70 percent loss of applied N fertilizer. Two basicapproaches may be used to solve this problem. One is to regulate the timing of Napplication based on needs of the rice plant, thus partly increasing theefficiency of the plants use of the applied N. The other is to increasethe ability of the rice root system to fix its own N (Table 4). The latterapproach is a long-term strategy, but it would have enormous environmentalbenefits while helping resource-poor farmers. Although N use has increased,still a large number of farmers use very little of it, primarily due tonon-availability, lack of cash to buy it, and poor yield response or high risk.Furthermore, more than half of the applied N is lost due to de-nitrification,ammonia volatilization, leaching and runoff. It is in this context thatbiologically fixed N assumes importance. Furthermore, farmers more easily adopta genotype or variety with useful traits than they do with crop and soilmanagement practices that may be associated with additional costs.
Table 4. Conventional and Future Biological NitrogenFixation (BNF) Systems, their Potential and Feasibility
| BNF | N supply | Rice Yield | Rice | Technology | Feasibility |
Conventional BNF systems | |||||
Free-living/Associative | 50-100 kg/ha | 3-6 t/ha | ANFS NAE NUE | 3-5 years | High |
Green manure (Azolla, Sesbania) | 100-200 kg/ha | 5-8 t/ha | NAE NUE | Available | Low |
Future BNF systems | |||||
Endophytic | ? | ? | Endo+ fix+ NUE | 3-5 years | High |
Induced symbiosis (Rhizobia, Frankia etc.) | > 200 kg/ha | > 8 t/ha | Nod+ fix+ NUE | > 5 years | High |
Nif gene transfer | > 200 kg/ha | > 8 t/ha | nif + fix+ NUE | > 5 years | High |
ANFS = associative N2 fixationstimulation; NAE = nitrogen acquisition efficiency; nod =nodulability; NUE = nitrogen utilization efficiency; Endo =Endophytic; fix = N2 fixation ability;nif = N2 fixation geneRecent advances in understanding symbiotic rhizobium-legumeinteraction at the molecular level, the discovery of endophytic interactions ofN fixing organisms with non-legumes, and the ability to introduce genes intorice by transformation have stimulated researchers world-wide to harnessopportunities for N fixation and improved N nutrition of rice. The developmentof symbiotic N2 fixation between legumes and Rhizobia is a multi-stepprocess in which genes from both host plant (nodulin genes) and bacterium(nod, nif, exo, lps, and ndv genes) play essential roles (Khush andBennett, 1992). Small signal molecules pass between the two organisms,activating genes and eliciting developmental responses which culminate in theformation of a cluster of bacterial cells rich in nitrogenase and protected fromexternal O2 by a complex molecular barrier. Nodules take sucrose fromphloem, convert it to succinate, and through bacterial respiration generate theATP and reduced ferredoxin required for conversion of N2 to ammonia.The plant component of the nodule takes up the ammonia and assimilates it intoglutamine and asparagine in temperate legumes or into the ureids, allatonic acidand allantoin in tropical legumes. The assimilate is then taken to the rest ofthe plant via the xylem. The engineering of plants capable of fixing their ownnitrogen is an extremely complex task, requiring the coordinated and regulatedexpression of 16 nif genes; 8 core genes (B, E, D, H, M, N, K, V), and 8housekeeping genes (S, T, Q, U, W, X, Y, Z) assembled in an appropriate cellularlocation (Dixon et al., 1997). Additional genes to maintain nitrogenase in anactive form may also be needed. Dixon et al. (1997) suggested that plastids mayprovide a favourable environment for nif gene expression and the damageof nitrogenase enzyme can be protected from oxygen by regulating that nif genesfunction only in the dark.
Once incorporated, these genes can become part of theseed-based input in rice with high potential of adoption. This becomes moresignificant when it is realized that every tonne of rice harvested containsabout 12 kg N, half of which comes from soil N and biologically fixedN2. The share of biologically fixed can be increased to suffice theentire need of rice plant. In that case the yield gap due to nitrogen may bereduced a to bare minimum. Currently, it appears a dream but is reasonable andrealizable, as nodule formation is a reality (Reddy et al., 1998).
4.2.2 Integrated fertilizer use and balanced use offertilizers
In addition to chemical fertilizer, there are avenues toaugment it through organic manure, biological nitrogen fixation, and theadoption of Integrated Plant Nutrition Systems (IPNS). Recent efforts of IRRI intransferring the nodulating genes to rice roots is an innovative approach whichmay help rice plant fix atmospheric nitrogen for its own and future use. Whilethis is recognized as a breakthrough using biotechnological tools, futureresearch should be based on the current gains to create a nodulation rice plantin the near future. Until that is accomplished, the addition of a legume cropeither in rice - wheat rotation or in a rice - rice system would beimperative.
Soil degradation and quality deterioration limit crop yieldsin many intensively cultivated farms in Asia. Changes in organic matter and soilnutrient supplying capacity, nutrient imbalance and multi-nutrient deficiency,waterlogging and iron toxicity, soil salinity and alkalinity, and development ofhard pans at shallow depths are some of the major indicators of deterioratingsoil quality. A lot of yield gaps can be attributed to knowledge gaps.Techniques (Balasubramanian et al., 1998; Cao et al., 1984) which can be used tohandle the soil degradation, include the chlorophyll meter (SPAD) and leafcolour chart (LCC), N placement methods, use of modified coated urea materials,phyto-availability soil tests, nutrient-efficient rice varieties, periodic deeptillage to exploit the subsoil N reserve, catch crops to tap pre-riceaccumulated soil nitrate, and use of biofertilizers.
Phosphorus, potassium, sulfur and zinc deficiencies in riceproduction have been increasingly observed in Asia. Therefore, more attention isneeded in this direction. A balanced use of fertilizers is equally as importantas other issues.
4.2.3 Water and irrigation
Water is essential to rice cultivation. Adequate water supplyis one of the most important factors in rice production. In Asia, the rice cropsuffers either from too little water (drought) or too much of it (flooding,submergence). Most studies on constraints to high rice yield indicate water asthe main factor for yield gaps and yield variability from experiment stations tofarms. A recent study conducted by the International Water Management Institute(IWMI), estimates that by the year 2020 a third of the Asian population willface water shortages. The next wars may be fought over water (Gleick, 1993). Thegrowth rate in the development of irrigation has already declined (Barker et al.1998). Even the existing irrigation systems are labeled as inefficient based onthe irrigation efficiency calculated as the ratio of requirement to thepercentage of water used. With the growing scarcity and competition for waterthere is an increased demand for research to identify potential areas forincreasing the productivity of water in rice-based systems. The major challengefor research in the coming decade lies in identifying specific situations forthe optimum combination of improved technologies and management practices thatcan raise water productivity at farm, system, or basin level.
Improved water use at the systems and farm levels areimportant considerations. Development of on farm water reservoirs for waterharvesting, selection of drought tolerant varieties, land leveling, subsoilcompaction, and need based irrigation scheduling may play a major role inincreasing water use efficiency and decrease yield gaps.
4.2.4 Integrated crop management (prescriptionfarming)
Based on the extensive and critical testing of rice varietiesand the crop management technology, it is possible to develop aprescription rice farming for individual farmers and each situation.The concept was tested on a limited scale in Indonesia during1996-1997.
It is essential, therefore, that crop management practicesshould not be applied in isolation but be holistically integrated in IntegratedCrop Management Packages (ICMPs) with flexibility for adjustment to fit toprevailing environmental, socio-economic and market factors. The development ofICMPs, which are similar to the Australian Rice Check package, and theirtransfer could effectively assist farmers in many countries to narrow the yieldgaps as well as to reduce rural poverty. The ideal ICMP, however, must aim toimprove farmers knowledge not only on crop production and protection butalso on the conservation of natural resources and market dynamics. This requiressubstantial improvement to the system of collection and dissemination ofinformation on rice, its production factors, and its technologies as well as themodification of the extension systems in many countries.
4.3 Bridging the Yield Gap
A gap between the potential yield that can be achieved atfarmers field level and what they actually get is very wide (Table 5).Bridging this yield gap offers a very lucrative opportunity to produceadditional rice even by using the available technologies.
Table 5. Rice Yield Gap (kg/ha) in DifferentAgro-Ecological Zones and Rice Eco-Systems in Asia (Evenson et al.1996)
| Country | AEZ/Ecosystem | Best Farm | Actual Farm | Gap |
Southern India | Warm and semi tropics/irrigated | 4562 | 4012 | 550 |
Eastern India | Warm and sub-humid tropics/irrigated, rainfed, lowland,flood-prone, upland | 3802 | 2041 | 1761 |
Bangladesh | Warm humid tropics/irrigated, rainfed, lowland, flood-prone,upland | 3937 | 3055 | 882 |
Northeastern China | Warm arid and semi-arid/irrigated | 8654 | 5617 | 3037 |
Central China | Warm and sub-humid subtropics/irrigated, rainfed, lowland,upland | 9080 | 5297 | 3783 |
Nepal | Warm and sub-humid subtropics/irrigated, rainfed, lowland,upland | 3940 | 2267 | 1673 |
Northern China | Warm cool humid subtropics/irrigated | 8361 | 5257 | 3104 |
Western China | Cool subtropics/irrigated | 9207 | 5465 | 3742 |
4.4 Reversing Yield Decline
The yield decline appears real even at farm level. To reversethis trend, a strong research base is essential on an area specific basis,rather than on factors cutting across the continents. Setting up of a jointFAO/IRRI/NARS programme to identify causes, and arrest the decline wasrecommended by Cassman et al. (1997).
4.5 Policy Support to Increase Production
Government policies provide the environment to benefit fromresearch investment, improve productivity, alleviate poverty, ensuresystems sustainability, protect the environment, and provide foodsecurity. It is therefore imperative that through appropriate policies,socio-economic adjustments should be effected in terms of input-output pricing,institutional support, and to redress the needs of rice farmers in order tocomplement the technological gains.
4.5.1 Credit
Drastic policy changes are needed in making credit facilitiesavailable to small and marginal farmers. The interests of these producers andrice policy makers are inter-linked.
4.5.2 Input availability
Fertilizers, especially nitrogen, play an important role inrice production and productivity. Farmers need adequate amounts of fertilizer atthe right time for obtaining high yields in rice cultivation. The supply offertilizers needs to be decentralized to village markets and the quality offertilizers should be assured. Small farmers are usually unable to buysufficient quantity on time for application; hence, the provision of villagecredit could greatly help them. The Bangladesh Grameen Bank is an interestingexample of providing rural credit to landless and resource-poor farmers. Theloan proposals are received by the bank only on a group basis (at least 5persons), focusing on technology loan, housing loan, joint loan and general loan(Dadhich, 1995). The principle of the Grameen bank could be deployed in otherdeveloping countries, with some modification for adaptation to local conditions.The problems of credit and input supply cannot be quickly resolved unless thereis strong government intervention. The issue of village credit and input supplyis being tackled where FAO and Governments are implementing Special Programmesfor Food Security (SPFS).
4.5.3 Institutions
Availability of agricultural credit, inputs (seeds,fertilizers, pesticides) supply, availability and quality of contract servicesand machinery for different farm operations, and repair and maintenance servicesin rural areas will influence the rate of adoption of knowledge intensivetechnology (Price and Balasubramanian, 1998). The government and privateinstitutions associated with credit, input and pricing directly influence theadoption and level of the use, and thereby the yield level. The kind ofproduction environment provided by these agencies must be harmonious as any oneof these factors is capable of becoming a bottleneck factor.
4.6 Quality Seed
Use of quality seed is the first and foremost way of realizingthe yield potential of the recommended technology. High quality pure seedensures proper germination, crop stands, freedom from weeds and seed borne pestsand diseases. It is recognized in general, that quality seed ensures 10 to 15percent higher yields under the same set of crop management practices. In thecase of superior quality rice, it even ensures higher price and profit.Unfortunately, in most countries sufficient quantities of certified seed are notavailable from all the seed sources put together. As a result more than 80percent of the area is cultivated using farmers own seed. Thus, there areseveral issues associated with the use of good quality seed. While the privateseed producers need to be encouraged to produce more seed of the releasedvarieties and hybrids, governments have to come up with proper legislation wherethe seed industry can prosper. Even an ambitious programme cannot stop the useof self-grown seeds (now that CGIAR system and most countries have rejectedTerminator Technology) by the farmers, thus knowledge can play itspart.
4.7 Post-Harvest Loss Reduction
Introduction of more efficient technologies for handling,drying, storage and milling rice at the village level is essential to reducepost-production losses (PPL). The present impressions are that post-productionis labour intensive, as the operations involve harvesting hand-reaping, fieldsun-drying before threshing, threshing by trampling, and wind winnowing. Thisresults in poor quality milled rice including grain discoloration. The physicallosses are more in wet season harvests, with problems in drying, and the use ofantiquated mills. Basic beliefs are that people in communities whose livelihoodis affected are likely to provide their own motivation for change to ensureincreased benefit for themselves. It is also believed that the local farmers andentrepreneurs are, therefore, to be given the opportunity to define theirpost-production needs and to be consulted in the selection of appropriatetechnologies. But one must also bear in mind that community organizations arerequired to make concerted efforts in the introduction of newtechnologies.
4.8 Research and Knowledge Transfer
The support of research and extension can ensure the effectivebridging of yield gap of rice. Farmers adoption of the above-mentionedimproved technologies depends on the capability of national agriculturalresearch centres and extension services, which need more government resourceallocation and training. The research scientists should understand well thefarmers constraints to high rice productivity and provide them withappropriate technological packages for specific locations to bridge the gapunder participatory approaches (IRRI, 1998; Price and Balasubramanian, 1998).The extension service should ensure that farmers use correctly andsystematically recommended technological packages (ICMPs) in the rice fields,through effective training and demonstrations. For example, only relevantapplication of nitrogen fertilizers from seeding to heading, in terms ofquantity and timing, will make significant contributions to narrow the yield gapof rice while avoiding unnecessary losses of nitrogen, which increase the costof production and pollute the environment. The transfer of knowledge based onscientific principles aimed at altering farming practices requires a good fitbetween the knowledge system of the farmers and that of scientists (Price andBalasubramanian, 1998). If new components were added to the knowledge system andif these were couched in familiar terms, there would be latitude forexperimentation at the local level that could eventually develop into afunctional fit. The current blanket recommendation approach givesfarmers information without understanding it, and provides information but notthe knowledge.
5. CONCLUSIONS
· Rice is the life-blood of theAsia-Pacific Region where 56 percent of humanity lives, producing and consumingmore than 90 percent of the worlds rice. The demand for rice is expectedto grow faster than the production in most countries. How the current level ofannual production of 524 million tonnes could be increased to 700 million tonnesby the year 2025 using less land, less water, less manpower and feweragro-chemicals is a big question. Alternative ways to meet the challenge byhorizontal and vertical growth have their own prospects and limitations. Basedon this scenario, the bridging of the yield gap for producing more rice appearsto be promising.
· Development of more locationspecific technology for crop management as well as technology transfer andadoption, coupled with manpower development in appropriate areas, has to behandled by the countries themselves. The sharing, testing and utilization oftechnology and knowledge across the national boundaries have to be facilitatedby Regional and International bodies through various networks supported bythem.
· The Integrated Crop Managementapproaches, including available location-specific technologies coupled withactive institutional support from governments, particularly for input andvillage credit supplies as well as stronger research and extension linkages, canexpedite the bridging of yield gaps and thus the increase in production.Location specific packages of technologies moving towards prescriptionfarming could be made available and popularized. However, there is a needfor better understanding of the yield gaps and national policies on thisissue.
· The yield deceleration,stagnation and decline observed in high-yield environments must be arrested,first by systematic studies to understand the causes and then by the developmentof new varieties and crop management practices. As the phenomenon affects themost productive ecosystem - the irrigated rice, and the permanent asset - thesoil, it is of great concern in which Eco-Regional Initiatives and AEZs networksmay help.
· Technical knowledge is animportant factor in determining the adoption of improved crop managementpractices and increased yields. Transfer of knowledge intensive technologies hasto receive priority. The bridging of knowledge gaps can bridge yield gaps.New paradigms need to be added to transfer and use newer seed and knowledgebased technologies under new policy environments.
· Yield variability is drivenprimarily by variability in the natural environment, and the challenge toresearch workers is to confront such variability in productivity by genetic andinput manipulations. On the genetic side, there is ample evidence thatconsiderable progress has been made (and can be further expanded) in exploitingnatural tolerance to both biotic and abiotic stresses, which are polygenicallycontrolled. But the diversion of resources towards risk reduction in phenotypicexpression must be traded off against more direct progress in terms of meanyield performance. Thus, one has to consider the trade-off between high yieldand yield stability. Development of varieties with high stability may thereforebe considered.
· The efforts to break the riceyield ceiling (NPT rice, hybrid rice, and agronomic manipulation) need to begeared-up to attain higher yields. The technology must be made available throughIRRI and FAO operated networks for testing and deployment by NARS. However,hybrid rice is the only technology available at present for raising the ceilingof rice yield potential.
· Technologies to decrease thecost of production and increase profitability must be considered very seriouslyat the same time. Issues in poverty alleviation, social justice anddiversification in agriculture are inter-linked and should be handled at thatlevel. The Asia-Pacific Region has the resilience to meet its future demand andremain a net exporter of rice, provided concerted efforts are continued withgreater vigor and thrust.
· The trade globalizationprovided by GATT, WTO and COMESA, and geographic comparative advantages ofproducing a crop, can provide major incentive for farmers to strive hard andbridge the yield gap. The Region may also focus on other continents to answerquestions. Africa can be a promising Future-Food-Basket for Asia,but concrete policy framework and support background under the South-SouthCo-operation and NAM must be added. The combined strength and synergistic linksbetween Asia and Africa can work wonders. This can be a boost and provide asolid platform for a shared prosperity for both continents.
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