6. Lessons from the green revolution:
towards a new green revolution

Technical background document
FAO, 1996


1. Introduction

1.1 The current perception of history indicates that it is only about 100 000 years ago – some 3 500 generations – that modern humans left the savannahs of East Africa to spread over the entire planet. Since hunters and gatherers settled 10 000 years ago (350 generations) and began relying on food produced from agriculture, there have been major productivity increases from crops and domestic animals. These gains are a result of the interplay of natural selection and deliberate choices of seed for the next season and of animals from which to breed. They also reflect a growing understanding of the farming environment, resulting in improved management techniques. Food production also expanded through the breaking of new land. As long as human populations were small, increased demands for food could also be met by clearing new land for crops and livestock. Global demands for food have been met by a combination of these strategies.

1.2 In the last three decades, productivity increases for the major cereals, rice, wheat and maize, have been a result of the incorporation of scientific advances in plant breeding with technological packages that have allowed the yield potential of the crops to be realized more fully and under conditions experienced by farmers from developing countries. These increases have been called the green revolution. Scientific advances have been supported by significant growth in the commercial sectors providing inputs to agriculture; infrastructures have improved to cover large and small farmers previously beyond the reach of technological innovations.

1.3 In spite of efforts to slow down global population growth, human populations continue to increase and the pressure on existing agricultural land is rising. The area available for suitable agricultural expansion dwindles on all continents. There are still, however, significant areas of Africa and Latin America that can be opened up for agriculture. The high costs for indigenous forest dwellers and for forest and savannah vegetation and biological diversity now deter many governments from pursuing this strategy. The adoption of Agenda 21 and the Rio Declaration during the United Nations Conference on Environment and Development (UNCED) in 1992 by all United Nations Member States has confirmed global concerns for the natural environment and its peoples. In most regions, in the future avenues must be found to increase food production for the food-insecure other than the large-scale conversion of fragile natural habitats into farmland. As conventions based on Agenda 21 principles (e.g. relating to biological diversity, climate change and desertification) come into force, nations are agreeing to legally binding frameworks for sustainable development.

1.4 Joint adherence to these conventions in order to ensure a stable and predictable environment for agricultural production is essential to the determination to meet the global food security challenge and to meet the growing demand from global food consumers.


2. Improving food security for the poor - the alternatives

2.1 Food-insecure people neither consistently produce enough food for themselves nor have the purchasing power to buy food from other producers. During times of famine, food may simply not be available at any price. Given that concerns for the integrity of natural habitats will limit significant further areal expansion of agriculture, other strategies must be found to feed a global population that may exceed seven billion in 2010. A number of alternative scenarios have been put forward (McCalla, 1994). They fall into two distinct groups.

2.2 The first scenario, supported by some analysts and with reference to current economic growth in Southeast Asia, assumes a significant development of the post-General Agreement on Tariffs and Trade (GATT) global economy. In this scenario, continued growth in world trade will allow food-deficit countries in the South to produce and export industrial goods and services that should enable them to purchase significant quantities of food from the food-surplus countries of the North. Many of these rich developed countries have considerable unused production potential, given their technological expertise and their marketing infrastructures. These intensive production methods are being adapted to meet modern requirements of sustainable development. For this food to reach the food-insecure in poor countries, the development of effective national food security policies will be required. These must ensure higher food entitlements for both the rural and urban poor through wider access to food made possible by income generation and employment. While North-South trade may improve national food security in developing countries, it does not directly follow that it will influence household food security for the poor in these countries as a group, or secure greater access to food in remote localities.

2.3 The second scenario, thought by many analysts to be more realistic, suggests that poor countries of the South must increase their own food production significantly and in such a way that it specifically alleviates food insecurity. Towards this end, a number of mechanisms may be invoked:

2.4 There is ample experience now to show that farmers’ willingness to increase food production in many developing countries is closely linked to the existence of markets for their produce 1. Similarly, the adoption by smallholders of improved management techniques on their farms seem to occur when there is ready access to input supplies and assured markets with fair and predictable prices for the produce (Crosson and Anderson, 1995).

2.5 The implementation of the agreements from the Uruguay Round within the World Trade Organization (WTO) is being watched closely in both developing and developed countries. In spite of considerable food purchases in the North by the developing countries, it is now much too early to say how far the first scenario (the reversed industrial and agricultural commodity flows) will materialize, and whether the North (including the countries of the former USSR) ultimately will have the capacity and political will to produce sustainably larger quantities of food for export. (Some will claim that agricultural production at present levels in the North is not wholly sustainable [Ehrlich, Ehrlich and Daily, 1993; Pimentel et al., 1994] but policy changes towards environmentally sustainable agriculture are increasingly being put into effect in the North.) It is also uncertain whether national developments in the South will enable the poor and, most likely, food-insecure to gain adequate access to the imported food (i.e. the dilemmas of national versus household food security). It will require a concerted effort from countries both in the North and the South in all sectors of their economies to facilitate this scenario. These considerations suggest that such a scenario cannot be the main thrust of global efforts to improve food security rapidly for the poor. Hence, food production must be increased also in the food-insecure countries themselves.

2.6 The experiences accumulated through general development studies and observations of the older green revolution strongly suggest that more general market forces and government market actions override technological packages. Technology alone cannot secure the production of food or access to it, nor can policies alone achieve this. The adoption of available technology largely depends on the incentives farmers perceive from them, and incentives are closely linked to markets; consequently, the essential tasks are:


3. The green revolution and the evolving research paradigm

3.1 Technological progress in modern agriculture builds on the experience gained from almost 150 years of scientific endeavours. The green revolution in wheat, rice and maize forms an integral part of this development. The foundation is a science-based technological ability to modify the environment so as to create more optimal conditions for crops and livestock than nature alone can offer (i.e. if it is dry, irrigate; if soil fertility is low, fertilize; if pests and weeds invade crops, spray or dust; if livestock are threatened by disease, vaccinate and medicate; or if more energy is needed to till the land, mechanize and use fossil fuels). Yield increases in the farming systems of the industrialized countries over the last 150 years can be interpreted as the implementation of this paradigm. The green revolution of the 1960s and 1970s was squarely based on it, where the improved varieties of rice and wheat could benefit from the use of external inputs (including water) that provided good growing conditions for realizing the genetic potential of the new varieties. The creation of socio-economic enabling environments that opened up for the use of these inputs and created markets for the sale of the produce was an integral part of this change.

3.2 As further applications of green revolution technologies are explored, opportunities arise (Sanchez, 1994) for breeding crop varieties that are tolerant to adverse soil conditions (salt-tolerant rice, maize adapted to highly acid soils, more drought-resistant sorghums and millets); the introduction of new crops into, for example, marginal areas (sweet potato and cassava for maize); enhanced soil nutrient cycling (with selected tree species to recover leached nutrients below the rooting zone of crops); maximization of the use of organic sources of nutrients, including biological nitrogen fixation, with supplements of strategically chosen chemical fertilizers; reliance on genetic pest and disease resistance to replace, either partially or fully, chemical and mechanical pest control; the active use of functional biological diversity, where predators and other natural control agents of pests and diseases are actively encouraged through the maintenance of complex ecosystems within and adjacent to farming activities; and increased production from naturally trypanosomiasis-tolerant cattle and small ruminants that can lower the need for large-scale tsetse fly eradication, with its many ecological implications. There are large rural populations that are excluded from access to credit and markets, but where structural changes are not imminent. These populations cannot benefit from conventional food production strategies and so require alternative yet science-based approaches.

3.3 Pursuing the goals of increased productivity per unit area and per unit of labour involves many of the tools of the existing green revolution technology, adapted to the needs of rural food-insecure people. It would allow farmers who live on fertile and otherwise suitable land to learn and to raise agricultural productivity on a sustainable basis. It also attempts to draw more of the poorer farmers into sustainable, higher input-higher output agriculture as a means of poverty alleviation and to increase food security in the rural areas. The green revolution also considers farmers in more marginal areas as well as those who, in the near future, will not be able to benefit from the value of using higher inputs. Their well-being can be improved by creating fiscal and policy environments that encourage them to utilize proven or improved germplasm, obtained from local resources or developed especially for their particular conditions. The possibilities include creating more productive farming systems such as mixed crop-livestock systems, the production of leguminous cover crops and the introduction of new crops, including cash crops. Secure land tenure arrangements and access to credit, for women as well as for men, are also important constituents.

3.4 It is important to realize that:

4. Lessons from the green revolution

4.1 The green revolution was a technology package comprising material components of improved high-yielding varieties (HYVs) of two staple cereals (rice and wheat), irrigation or controlled water supply and improved moisture utilization, fertilizers and pesticides and associated management skills. The utilization of this technology package on suitable land in suitable socio-economic enabling environments resulted in greatly increased yields and incomes for many farmers in Asia and in some developing countries elsewhere. Many of these farmers were well versed in irrigated farming systems already. Statistics indicate that yields of these two cereals, and of maize, approximately doubled between the 1960s and the 1990s (see Box 1). The green revolution has been a major technological achievement, and its effects are continuing. Recent studies of the impacts of the green revolution also suggests that it extended beyond the rice/wheat producers of Asia to include other crops and other socio-economic settings and also to some areas of Africa (with reference to Nigeria, see Goldman and Smith,1995). Eicher (1995) suggests that commercial farmers in what is now Zimbabwe launched a green revolution for maize in 1960, five years ahead of the green revolution in India, and that Zimbabwe repeated this with a second green revolution – for smallholders also – in the first half of the 1980s. HYVs of wheat have had success in the Republic of South Africa, Zimbabwe and Kenya. It is thus not wholly true that Africa missed out on the green revolution. The successes of the technology packages, whether in Asia, Africa or Latin America, were closely linked to the existence of favourable socio-economic and institutional enabling environments, where active market possibilities played important roles.

4.2 The green revolution technologies were not without their problems: the need for a significant use of agrochemical-based pest and weed control in some crops has raised environmental concerns as well as concern about human health; as irrigation areas expanded, water management required skills that were not always there; gender roles were shifted; and there were new scientific challenges to be tackled. Although HYVs often replaced older landraces, it is less certain that the world has actually suffered significant genetic erosion.

4.3 The greatest beneficiaries of the green revolution may be the consumers. Real food prices in Asia, indeed throughout the world, have steadily declined over the past 30 years through the application of yield-increasing, cost-reducing technologies built around improved seed-fertilizer-weed control components. Lower real food prices benefit the poor relatively more than the rich, since the poor spend a larger proportion of their available income on food. The green revolution technologies have also led to increased rural incomes. Stationary threshers, tubewells and flour mills have all reduced the drudgery of women. The move to a higher-input environment naturally favoured those farmers who had access to capital and skills. They strengthened their roles in society, sometimes at the expense of less well-endowed groups. Many studies have also claimed gender biases in the development of the green revolution. The established roles of women in the farming systems were challenged by the new technology and the new economic structures. Efforts to introduce the new technology may often have overlooked the rights of women to benefit also from the technological advances and reduced their power base (Shiva, 1991; Serageldin, 1995).


Box 1


During the period 1963-1983 (important green revolution years) total production in developing countries of paddy rice, wheat and maize rose by 3.1, 5.1 and 3.8 percent per year. During the next decade (1983-1993) annual production increases were reduced to 1.8, 2.5 and 3.4 percent, respectively.
Yields per hectare rose less steeply for the same three crops during 1963-1983: 2.1, 3.6 and 2.9 percent, falling to 1.5, 2.1 and 2.5 percent during 1983-1993. This is partly explained by less productive areas being brought into cultivation and by difficulties in sustaining yield increases under more intense cultivation practices. Although Africa contributes less to global cereal figures than Asia and Latin America, total annual production increases for Africa have been higher for rice and wheat than global developing country averages, particularly during the last decade (6.0 and 6.6 percent, respectively), but slightly lower for maize (an important staple for many) at 2.9 percent. For sorghums and millets, on which many food-insecure dryland people depend, African farmers have recorded greater total annual production increases than the developing country averages during the last decade (+1.8 percent as against -1.5 percent for sorghum, and +2.5 percent as against -0.4 percent for millet).

However, while African farmers during the period 1963-1983 had approximately the same yield per hectare as the developing country average, they have not been able to increase productivity during the last few years compared with other developing regions: mean yields for paddy rice, wheat and maize in the period 1991-93 were
2 029 kg/ha, 1 731 kg/ha and 1 369 kg/ha, respectively, against global developing country averages of 3 488, 2 420 and 2 627 kg/ha.

Many African farmers did not benefit from the green revolution in the way farmers on other continents were able to.

4.4 With hindsight it is easy to see the profound and often unforeseen impacts that the green revolution technologies had in many farming communities beyond the actual production sectors. In this sense, the green revolution shares the pros and cons of many of the technological advances that have changed and built modern global societies. There have been both winners and losers. The green revolution clearly averted a major food crisis in Asia, it became the foundation for startling economic growth in China, Southeast Asia and South Asia. It inspired the subsequent development of more environmentally benign methods of, for example, pest control in rice. Wheat and rice prices have continued to decline in the world market, offering cheaper food for all, not least for the huge numbers of urban poor in the developing countries.

4.5 Experiences with the green revolution are varied. A recent review (Freebairn, 1995) of more than 300 academic studies on the green revolution during the period 1970-1989 concludes that the most obvious trend to be found in the studies is that authors from Western developed countries, those employing an essay approach and those looking at multicountry regions, tended to report increased income inequalities. Authors of Asian origin, especially those with study areas in India and the Philippines and using case-study methods, tended to report that increased income inequalities are not associated with the new technology. Over 80 percent of the studies reviewed by Freebairn concluded that greater inequalities resulted. However, several authors, and notably a moderate green revolution critic such as Lipton (Lipton and Longhurst, 1989), acknowledge that some of the more persistent claims on declining welfare associated with the green revolution have little empirical support. Goldman and Smith’s (1995) case-studies from villages in India and northern Nigeria suggest that broad sets of mutually reinforcing changes have been associated with the apparent adoption of new agricultural technologies. Zimbabwe’s relative successes with maize both for commercial and smallholder farmers (Eicher, 1995) relied heavily on institutional infrastructures, and on (possibly unsustainable) economic incentives. The technological packages as such have been necessary but not exclusive components of success in reducing food insecurity.

4.6 The many studies, and the experience gained by development organizations, have nevertheless given new insight into social science issues and scientific and technology aspects. Armed with this and the knowledge that there are still almost 800 million food-insecure people requiring support in the form of initiatives for a green revolution, the prime goals of the renewed effort must be to create improved conditions for increased agricultural production for increased national food security and to ensure that the food-insecure benefit from production increases.

4.7 While the productivity gains in rice and wheat in Asia have been significant, farmers growing other crops and those in other parts of the developing world have also responded to increased demands for food from growing populations over the last three decades with modest but respectable productivity increases. These increases have not, with the possible exception of maize, been based on the large-scale application of green revolution technologies. It is clear that limited research efforts have been devoted to globally less important crops than rice and wheat. It has been argued that this may explain why productivity gains have been smaller in many minor African crops (United Nations, 1995). Maredia and Eicher (1995), using wheat research as an example, have also argued that the distribution of research funds between international and national research institutions requires rethinking. Tribe (1994) and Swaminathan (1994) both argue strongly for the role of research to sustain productivity growth. In particular, they argue that the research must not be restricted to the conventional staple cereals but must be increasingly focused on other crops and on livestock, poultry and fish, which are all important for well-balanced diets for the poor. Many of the food-insecure could benefit from more productive mixed farming systems on which fewer research efforts have been expended.

4.8 Other crops and livestock have not so far responded equally to yield enhancement research, but the production of horticultural crops and of livestock has nevertheless increased. Less favourable enabling environments for yield increases may also explain the slow progress in farming systems based on other crops and animals. There has been a focus on cereals, which constitute about 60 percent of human foods, with relatively less attention to vegetables, livestock and fish products. The statistics are normally kept at the national level, thus giving less insight into changes experienced at the household level.

4.9 In Africa and Latin America, increased food production has mostly been based on expanding the cropping area, often into more marginal lands with a lower yield potential. Frequently, farmers have been forced on to marginal lands as a result of population pressure, which has intensified traditional shifting cultivation practices and reduced the stability of production. Until recently, incentives for the intensification of production have often been absent in many African countries. With little access to either appropriate technologies, capital or skills to implement new farming systems, farmers have extended their proven farming practices on to new land. Labour productivity has been low and access to mechanization and energy to enhance labour productivity very limited. Increased urbanization, with the associated expansion of markets, and a growing political awareness of the increasing numbers of both rural and urban food-insecure in Africa now appear to offer more realistic enabling environments for the development and implementation of new and appropriate agricultural technologies (Goldman and Smith, 1995). Political changes in Eastern European and other countries with transitional economies pose new challenges to production systems, with greater diversification likely.

4.10 Similarly, the recent changes in the global political climate and the lowering of barriers to international food trade may offer incentives for the development of more sustainable farming practices in developing countries in Africa, Asia and Latin America and also in the developed countries. A wider, more equitable access than was possible in the past to relevant farming technologies for both men and women farmers will be a prerequisite for improving access to food. Government extension services need to take the lead in fostering conditions that encourage non-governmental organizations (NGOs), agribusinesses, mass media, educational institutions and farmers’ groups to develop complementary delivery systems of innovations and revived traditional knowledge. Innovative schemes to encourage more efficient and relevant extension services in developing countries should be devised and implemented.

4.11 Politicians will need to ensure that appropriate technologies become available for implementation in areas where they can contribute substantially to improved food security. Issues of equity within and between generations, environmental concerns (including biological diversity) and national institutional ownership are central to the development and implementation of the new technologies. During the green revolution the variety of sustainable institutional arrangements necessary to underpin the technological changes were sometimes overlooked in some countries (Eicher, 1989) but, in other countries, strong institutional structures developed. There has now been a generation of farmers’ experience in green revolution agricultural development. With this historic insight, new possibilities can be offered to areas and groups of people who did not benefit from progress made in the green revolution.


5. Productivity objectives

5.1 Through the work of the international agricultural research centres (IARCs) within the Consultative Group on International Agricultural Research (CGIAR) and advanced research centres in the developing and developed countries, the genetic potential of the current generations of advanced breeding materials of crops and animals is reasonably well known. Where rice is concerned, some farmers in Southeast Asia have begun to equal the yields achieved on research stations but, for other crops, there are large yield gaps between research yields and farmers’ yields. Typically, dryland farmers obtain between one-tenth and two-thirds of research station yields each year, and most farmers normally reach less than one-half (see Box 2).

5.2 Such yield gaps are very common and cannot be explained by differences in soil and climate alone. This suggests that changes in the socio-economic enabling environments for farmers, including access to additional knowledge, have the potential to create large yield increases in farmers’ fields for a wide variety of crops. The incentives for narrowing the yield gaps, particularly access to markets for surplus produce, have often been lacking. The closing of the yield gap in paddy rice, albeit for a limited number of progressive farmers and at a high yield level, offers a fresh challenge to rice breeders and rice agronomists. This challenge is being actively pursued at the International Rice Research Institute (IRRI), where the production objective for rice is now 15 t/ha per year as compared with the current world average yield of 3.5 t/ha per year.

5.3 Some critics, such as Brown and Kane (1994), argue that the lack of yield gaps indicate that agricultural science is running out of fresh ideas on how to increase productivity. However, small yield gaps in rice demonstrate that research and extension can work in favourable socio-economic enabling environments. This situation is a further challenge to research. While it can be easily argued that there will ultimately be limits, it is also clear that research institutions still achieve sizeable yield increases with conventional research tools, that new tools from biotechnology are becoming available and that many crops and many livestock and fish breeds have not been subject to much improvement. A decade of genetic improvement on fish species such as Atlantic salmon and African tilapia has achieved 45 to 75 percent yield increases (see Figure). Genetic improvements for tree species have also just begun.


Box 2


At the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in Andhra Pradesh, India, CGIAR research scientists have been able to obtain about 6 t/ha per year of sorghum/maize plus pulses (chickpea/pigeon pea) in a double cropping system on vertisols. Traditional single-crop systems in the area typically yield only about 0.6 t/ha of sorghum or 1.2 t/ha of chickpea.
Similar yield gaps have also been recorded in Latin America and particularly in Africa, even under comparable growing conditions between experimental plots and farmers’ fields. Not only access to inputs but management skills are vitally important.

The research community can deliver greatly increased yields. The challenge is to find mechanisms that allow the farmers to narrow the yield gaps.


Figure: Trends in productivity gains for farmed animals

5.4 A clear objective of the green revolution is to narrow the present yield gaps without degrading the natural resource base. In a world of 800 million food-insecure people, the realization by farmers of the efforts of research workers is a credible objective. Realistically, if average annual farm yields per hectare approach two-thirds of research station yields under comparable climatic conditions, food availability will not be lacking. Increasing farm yields to this level and lowering the sizeable harvest and post-harvest losses (which may easily reduce food available for consumption by a further one-tenth to one-third depending on the crop, environments and markets) are both targets which are within reach. The main tools to implement the green revolution will be new modes of communicating with farmers, rejuvenation of extension systems and changes in the policy enabling environments. In particular, poverty reduction efforts will encourage resource-poor farmers to invest in soil and water conservation measures. Successes in extension derived from incentive schemes aimed at extension workers should also be pursued further.

5.5 Classical tools for germplasm enhancement formed the backbone of the green revolution. Recent advances in biotechnology, not available at the time of magic rice and magic wheat, including genetic engineering, have yet to manifest themselves significantly in varieties and breeds available to the tropical smallholder. With innovations still largely at the laboratory stage and subject to intense international debate concerning ethical, biosafety and intellectual property rights issues, experience to date suggests that it may take 10 to 20 years for them to reach farmers’ fields. Improved technology delivery systems are the key to bringing the benefits of science-based technology to small-scale farmers, including the benefits of genetic engineering. The heavy investments currently being made by private sector industry in developed countries in biotechnology, particularly in plant genetic engineering, indicate clearly their perception of future developments.

5.6 Provided precautionary principles are adhered to, the prospects for biotechnology remain good, particularly efforts to build genetic resistance to pests and diseases into useful crops and animal breeds. Crop and animal losses make up a significant part of the reduction in yields experienced by small farmers but their access to agrochemicals for controlling such losses is still limited. The limited education level of many smallholders often prevents a proper understanding of both the environmental and health risks associated with agrochemical use. Linking the use of genetic resistance to methods of integrated pest mangement (IPM) holds a lot of promise, particularly in view of the significant successes achieved in rice cultivation in Southeast Asia. It is fundamental that these and other advances in biotechnology do not bypass food-insecure farmers. It is, as always, possible that disease and insect resistance will break down, but the introduction of new combinations of resistance may be much faster than using conventional breeding methods.

5.7 Much of the advanced work in biotechnology is currently focused on farming issues in the developed countries and is not specifically designed to support tropical farmers. A major challenge is to ensure that the global community does not develop policies and procedures that will exclude tropical farmers and herders from benefiting from advances in biotechnology. Instead, a determined effort should be made to encourage the rapid transfer of safe and appropriate new technology also to those in greatest need. Since access to large genetic pools is important to biotechnological efforts to create improved crops and breeds, there is a strong challenge to retain the large genetic diversity in the present pools. This will probably encourage different approaches to the release of improved varieties and breeds as compared with approaches used during the green revolution. More of the final selection process is likely to remain with the farmers, who will actively select the material which they deem to be particularly suited to local conditions. The role of the farmers, both as curators and selectors of genetic material, should thus be redefined. This calls for new policies and procedures to ensure workable and just solutions to the new situation.

5.8 Genetic enhancement and biotechnology alone are, however, unlikely to ensure increased production in support of improved food security. For example, evidence from the recent drought in southern Africa indicates that about two-thirds of the yield increases obtained from improved sorghum varieties based on ICRISAT material can be traced back to better management at farm level, even during a time of severe drought. Extension efforts accompanying the release of higher-yielding improved seed are at least as important as the genetic material itself, also under low-input conditions. A recent CGIAR review of progress in marginal agriculture in West Africa indicates that moderate successes have also been recorded in low-potential areas. This is important for the social and political stability of less well-endowed regions, which often harbour a large proportion of those who are currently food-insecure. In these areas, where there are fundamental biological limitations to agricultural production, the focus must be on education and off-farm employment opportunities to reduce pressure on the land.

5.9 Moreover, there is evidence available that, for some livestock commodities, modern science is a long way from realizing the genetic potential of the producing species (see Figure, which schematically covers the 50-year period from 1940 for chickens, dairy cows, pigs and farmed Atlantic salmon). In tropical aquaculture, genetic improvements in carp species and tilapia over the last ten years have led to yield gains of from one-third to one-half, at the farm level over the last five years, offering hope of a growing availability of valuable protein at lower prices in the future. For fish species, and for some types of livestock, current research efforts appear to be at the lower end of steeply rising productivity curves. The maintenance and utilization of animal genetic resources for productivity gains and greater disease resistance are of increasing importance in the green revolution. It is also important to see these advances in the context of production systems, as smallholders frequently practise mixed farming as part of their food security strategies. Nutrition and health issues must also be addressed.


6. Sustainability objectives for the green revolution

6.1 There has been considerable progress since 1992 in defining sustainable development in operational terms. A particularly useful notion is the division of total capital to be maintained (or enhanced) within and between generations into four separate components: capital from nature, human capital, institutional capital and social capital. This concept (see Serageldin, 1995) accepts that the components may change in size, so that it is legitimate to allow (in a wise way) capital from nature to be spent in order to build, for example, human or institutional capital.

6.2 Sustainable agricultural development therefore assumes that actions taken must enhance the total sum of capital components, even though their relative proportions may change. While researchers are still struggling to find ways of quantifying the individual components, this approach seems to give more direct guidance in the evaluation of whether so-called sustainable interventions really contribute to the total capital.

6.3 The current concept of the green revolution attempts to ensure that all four components of the total capital are strengthened in ways which ensure that each reinforces the other. New communication tools have emerged which allow for a novel dissemination of knowledge in support of changes in farming systems.

6.4 Approaches to sustainable development also presuppose popular support for principles of good governance. Equity issues are central to sustainable development, both within and between generations, and they are therefore important. Truly participatory approaches to the introduction of higher-potential farming systems must be a prerequisite and aim at ensuring that otherwise vulnerable groups in the community, including the young, the old and women, become equitably involved in the planned changes.

6.5 During the green revolution it was observed that the lack of technical skills among farmers had been a disincentive to the adoption of more productive farming systems. As labour productivity must increase to improve incomes, the introduction of draught animals is therefore an important tool for increased productivity. With the lesson from the original green revolution in mind, it can be expected that once new seed and fertilizers are available, farmers will take up the new crop technologies and generate finance for further expansion, for example with tubewells for irrigation.

6.6 The genetically homogeneous monocultures of the green revolution increased the potential for massive pest and disease attacks on rice and maize, triggering in its turn the large-scale application of standard pesticides. In recent years, lessons learned from the initial phases of the green revolution have yielded innovative approaches to a more integrated pest management. A wide variety of techniques, including biological control, are replacing heavy applications of agrochemicals, particularly in rice production, for the tropical smallholder. FAO has played a leading role in the introduction of such techniques in Southeast Asia. The green revolution takes IPM as a starting point and explores more widely the interrelations between natural and adjacent ecosystems and farmland. Maintaining a multitude of options for pest, disease and weed control is a major principle of the new approach. By ensuring a large natural variability among pathogens and pests, it is possible to reduce the risks of creating resistance to specific control measures. Greater genetic variations within crops and livestock also offer new options for control. Another advance has been the development of the concept of integrated cropping system management, which includes both IPM and integrated nutrient management (INM).

6.7 The maintenance of large gene pools, in situ and ex situ, for important crops will remain very high on the agenda of the green revolution. Further advances in international cooperation towards this end will be actively pursued by the international research community in close cooperation with national agencies and within the context of international undertakings. The basis for development, which was hitherto largely focused on rice, wheat and maize, will be extended to other crops, including the mandated crops of the CGIAR. There is clearly further scope for exploration of the genetic potential for increased productivity even when external inputs are low, for example. by developing crop varieties that are tolerant to saline or acid soil conditions, or which can tap more efficiently strongly held soil nutrients. Drought tolerance and genetic resistance to diseases, pests and parasitic weeds need to be continually explored for their potential incorporation in new varieties for farmers’ use.

6.8 There is an increasing demand for livestock products, as a result of both population growth and changing dietary habits owing to increasing prosperity, not least in Asia. While many of the world’s poor still rely mainly on vegetarian diets, the genetic potential of large and small ruminants, pigs, poultry and fish will play important roles in improving human nutrition in the future. The maintenance and wise use of animal and fish genetic resources will remain essential. Past experience with livestock breeding in developed countries suggests that particular attention should be paid to ensuring the survival of local breeds and the genetic resources they represent. Genetic improvement of local breeds must also receive renewed attention in the effort to attain better animal nutrition and husbandry to exploit the yield potential of established improved breeds. The development of sustainable mixed crop-livestock systems forms an important part of increasing animal production.

6.9 A greater understanding of soil-plant relationships has created new platforms for nutrient cycling, thereby reducing the need for heavy fertilizer applications so commonly associated with the green revolution. In intensive farming systems, runoff from fields has caused pollution problems also in developing countries, where fertilizer use is otherwise low. In 1992, the average fertilizer consumption per hectare of cropland in Africa was about 20 kg of nitrogen, phosphate and potassium (NPK), against 300 kg in China and about 100 kg in the developed countries. In practice, in African smallholder staple food crops, applications of less than 5 kg/ha are common. Improving both the access to and the wise use of fertilizer are important components of the green revolution. There is no escape from some simple facts of severe phosphate deficiencies in many African soils and the need to ameliorate highly acid soils in Africa and Latin America to obtain significant yield increases. At the same time, there are technologies available for the enhanced use of atmospheric nitrogen through improved nodulation in legumes and from agroforestry practices, as pioneered, for example, by the CGIAR institutes, the International Center for Research in Agroforestry (ICRAF) and the International Institute of Tropical Agriculture (IITA). While the incorporation of effective nitrogen fixation in other major crops may become technologically feasible in the future, it is not likely to be decisive for the tropical smallholder during the next decade. Biological nitrogen fixation in crop plants and the use of green manure and leguminous trees all require water and nutrient resources and may be in competition with other crop plants. In some farming systems they may be complements to mineral fertilizer use rather than substitutes. Better utilization of subsurface nitrogen accumulations (which now often only contribute to groundwater pollution) by recycling through tree crops with deep rooting systems may become part of the green revolution approach.

6.10 Soil degradation is severe in many areas, both in highly productive regions and in more marginal lands. Severely eroded lands are extremely costly to rehabilitate. Preventive measures are much more cost-effective. Good land husbandry is another major principle of the green revolution. Soil conservation research has provided new options for sustainable land use, also in marginal areas, including low-cost farmer-friendly techniques of terracing, use of vegetative borders and agroforestry techniques. Similarly, conservation tillage using environment-friendly herbicides can play a major role in controlling soil erosion, improving moisture conservation and building up organic matter in addition to being a labour-saving technology. These alternative approaches are less labour-intensive than earlier techniques that farmers often found to be unsustainable within their production systems.

6.11 Good water management is another key to productivity gains in many tropical and subtropical farming systems. The disappointing performances of many large-scale irrigation schemes, in terms of their economy, has reopened the issue of the role of irrigated agriculture2 in a green revolution. The understanding of the underlying causes of past failures has improved, pointing to technical design faults, including: inadequate drainage; irresponsible water pricing schedules, which encourage the improper use of water resources; poor general maintenance and management of physical infrastructure; and inadequate knowledge transfers to otherwise inexperienced irrigation farmers.

6.12 Water management in the tropics and subtropics with high evapotranspiration rates and variable water qualities is likely to remain a challenge.

6.13 Modest increases in irrigated areas, often in the form of low-cost high-intensity schemes, particularly in Africa, will form an important element of new green revolution efforts. It will also be important to ensure that there is equitable sharing of water and land resources for communities practising different farming systems. Competition between, for example, pastoralists and irrigators for water and land should be minimized. Linked to the expansion of irrigation should be a new and better understanding of the role water can have in the spread of human diseases, and of how proper management and increased public awareness of health risks can help to reduce disease incidence. Close cooperation on such issues has developed among FAO, the World Health Organization (WHO), the United Nations Environment Programme (UNEP) and the United Nations Centre for Human Settlements, known as HABITAT.

6.14 Most farmers, not least of all those who are food-insecure, are also averse to risk. Their strategies often involve spreading risk over many activities. It may be more acceptable to them to encourage a wider integration of a multitude of crops, livestock and tree crops into smallholder production systems in order to reflect the approach to sustainable livelihoods that often prevails in economically marginalized communities. But one should not overlook the role that new cash crops can play for smallholders: the successes of the oil palm production system in Southeast Asia and soybean production for oil and protein in India are good examples of farming systems that offer potential for sustainable development. Non-wood produce offers still more scope for increasing sustainable utilization, combining the effects of potentially improved watershed management with increased contributions to meet dietary needs.


7. Target areas for the green revolution

7.1 Early and large gains from a green revolution are most likely to come from more fertile areas. That is, it is most important to capitalize on the better-endowed environments in regions where real food deficits exist. Increased food production, for the market also, induces greater economic activity, with subsequent positive effects – notably, augmenting incomes and employment, including for the poor. Increased production from more fertile areas will, in the first instance, improve national food security and improve household food security for poor farmers living in these areas. Experience has often shown that developing fertile lands reduces the pressure to bring more vulnerable areas under production.

7.2 Successful developments in better-endowed areas may be expected to encourage investment in more marginal lands as well. Marginal lands are not always vulnerable lands (e.g. the acid soil areas of South America and southern Africa) but they may offer less prospect for rapid and large returns on investment. However, slight improvements in production in marginal areas may benefit many of the food-insecure at the household level, and more directly than “trickle-down” effects expected from investments in high-potential areas. Less-endowed areas must also be considered in order to avoid creating social and political imbalances at the national or regional levels. With growing demands from expanding urban markets and the possibility of shifts in urban diets towards higher-value agricultural produce, as producers, today’s food-insecure may be offered new opportunities by the market to enter into growing economies or to find off-farm income opportunities generated by the generalized economic expansion.

7.3 Of particular interest to the urban food-insecure is the potential of peri-urban agriculture (often vegetable and smallstock production) to supplement the staple foods produced in the rural areas. Growing urban and peri-urban agriculture and forestry activities benefiting from the short distance to consumers with above-average purchasing power have a competitive advantage. There is unused potential both for food and fuel production and employment generation in peri-urban agriculture and forestry. Actual local land prices, or the value of land in other terms, may influence these developments.


8. New tools for the green revolution

8.1 The lessons from the green revolution taught that scientific advances alone cannot solve the food security problems of developing countries. Political leaders must create suitable socio-economic and institutional enabling environments, while access to credit and markets should play a key role in improving productivity. Greater equity does not necessarily arise from greater food production. The environmental consequences that the introduction of high-input/high-output agriculture can have are also appreciated, as well as the vulnerability of high-potential and low-potential lands alike when farming systems change dramatically. Sustainable progress nearly always involves broad popular participation, allowing people themselves to select from among the new tools and to blend these with the technological, social, cultural and economic settings which were created by their traditional systems.

8.2 Those countries that have achieved greater national and household food security, also for the poor, have a track record of strong political emphasis on agriculture, careful consideration of economic incentives for agricultural production, and human and economic investments in research, extension and training.

8.3 Armed with this knowledge, the world community can assist in supporting efforts in the poor countries and in the donor community to ensure that the results of research can be transferred to farmers and that the yield gaps that exist between proven practices in research and experimental fields, on the one hand, and on farmers’ fields, on the other, can be significantly narrowed. However, research efforts need to be promoted at the national and international levels to ensure that the time-lag between initiating research and the ability to provide results for farmers’ use will not limit new demands that will be put on food production by the year 2010 and beyond.

8.4 The main tools available for these efforts are:


9. Conclusions

9.1 There is an immediate need for a new thrust to the green revolution to meet the legitimate needs of the food-insecure, both at the national and at the household level. Growing population pressure in many countries adds to the urgency. The main objective is to assist farmers in developing countries to narrow, and hopefully close, the current yield gap between experimentally proven yields and those which farmers actually obtain.

9.2 There is an urgent need to increase investment in agricultural research, both from national funds and in the international donor community. There are considerable longer-term prospects in biotechnology, IPM and post-harvest processing that require determined efforts, particularly in developing those alternatives that specifically target the food-insecure. Also required are renewed efforts in agricultural research to achieve further yield increases in crops where the yield gap is small at present (notably for rice and wheat) and to encourage further productivity gains for livestock and in aquaculture.

9.3 The realization of the green revolution needs to happen in the context of sustainable development. Politicians must strive towards more equity within and between human generations, including their food security, as this is the foundation for the implementation of this technological change. What is needed is a global understanding of the serious shortfall in political commitment to agricultural development in many countries facing food insecurity and in the donor community.



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1 See also WFS companion paper 8 Food for consumers: marketing, processing and distribution.

2 See also WFS companion paper 7 Food production: the critical role of water.