The rediscovery of Mendel’s laws of genetics in 1900 opened up a new era in crop breeding in general, and wheat breeding in particular. Although the art of plant breeding is as old as the beginning of agriculture nearly 12,000 years ago, systematic research in the areas of genetics and cytogenetics, which commenced in the early part of the 20th century, created uncommon opportunities for improving the productivity, profitability, stability and sustainability of wheat production. Even before Mendel (1822–1884), plant hybridizers like Kolreuter, Knight, Gartner and Burbank were able to produce improved varieties of crops through careful observation and selection. The concept of sustainability to which we now attach great importance was recognised long ago as essential for sustained agricultural progress.
During the past 100 years, Mendelian genetics has helped not only to exploit naturally occurring genetic variability but has also accelerated the process of generation, manipulation and combination of new variability. We are now in a state of transition from Mendelian to Molecular breeding. Breeder’s eye for selection and for spotting the winner will continue to play an important part in successful plant breeding.
It is projected that global demand for wheat will increase by 40 per cent by the year 2020. Also, 67 per cent of the world’s wheat consumption will be in developing countries. Between 1961 and 1990, yield increases accounted for 92 per cent of the additional cereal production in developing countries. In the years ahead, there is no option except to produce more from less per capita land and water resources. Can we sustain the yield revolution in wheat? It will be useful to consider this issue in the context of the genetic pathways which led to the wheat revolution of the 20th century.
Wheat is a crop of great antiquity. We can identify at least 4 major phases in the evolution of wheat breeding during the 20th century.
Soon after the re-discovery of Mendel’s laws of genetics in 1900, systematic work on the genetics of resistance to stem, leaf and stripe rusts started. Selection from naturally occurring genetic variability also began.
During the early part of the 20th century, the major breeding challenges were in the area of resistance to rusts and grain quality improvement. A study of the yield improvement achieved between 1900 to 1930 in USA shows only limited progress. The emphasis was more on stability of production through disease resistance than on achieving quantum jumps in yield.
This period was marked by the introduction of cytogenetic knowledge and tools in wheat improvement. This phase of wheat improvement was characterised by widening the gene pool used by breeders, incorporation of genes for the semi-dwarf plant type, shuttle breeding and breeding to meet the challenge of physiologic specialisation in pathogens.
This phase is also generally referred to as the green revolution era. It was characterised by revolutionary progress in improving wheat production and productivity in several developing countries like India and Pakistan. The introduction of the semi-dwarf plant type enabled the wheat plant to yield well under conditions of good soil fertility and irrigation water management. Farmers who were used to harvesting 1 to 2 tonnes of wheat per hectare started harvesting over 5 tonnes/ha (Swaminathan 1993). In view of the widespread interest in this remarkable transformation in India’s agricultural destiny, it will be useful to summarise some of the highlights.
During 1942–43, the Indian sub-continent witnessed a severe famine in Bengal resulting in the death of nearly three million children, women and men. This prompted Jawaharlal Nehru, the first Prime Minister of Independent India to remark in 1948, ‘everything else can wait, but not agriculture’.
In 1964, a National Demonstration Programme was started in farmers’ fields, both to verify the results obtained in research plots and to introduce farmers to the new opportunities opened up by semi-dwarf varieties for improving very considerably the productivity of wheat. When small farmers, with the help of scientists, harvested over five tonnes of wheat per hectare, its impact on the minds of other farmers was electric. The clamour for seeds began and the area under high yielding varieties of wheat rose from four hectares in 1963-64 to over four million hectares in 1971–72. A small Government programme became a mass movement (Swaminathan 1993). Wheat production in India rose from 10 million tonnes in 1964 to 17 million tonnes in 1968. In 1999, Indian farmers harvested about 72 million tonnes of wheat, taking India to the second position in the world in wheat production.
Greater interdisciplinary collaboration among breeders, plant pathologists, agronomists, physiologists, soil scientists, entomologists, nemotalogists, economists and other social scientists, climatologists and policy makers was the principal factor responsible for the success of the green revolution. The green revolution era can also be termed the golden age in interdisciplinary and international collaboration in wheat improvement for sustainable food security. The concept of shuttle breeding transcended continental boundaries and a global college of wheat scientists emerged. Above all, the green revolution showed how to generate synergy between technology and public policy.
The last 20 years have witnessed great progress in using sophisticated approaches to wheat breeding. Hybrid wheat is reaching the possibility of large scale commercial cultivation. The use of genetic-cytoplasmic male sterility and of chemical hybridizing agents (CBA) are responsible for progress in the commercial exploitation of hybrid wheat. Different management practices such as lower seed rate, raised bed planting, split nitrogen application and different row width are being tried to enhance the expression of hybrid superiority. The cultivation of hybrid wheat is slowly gaining in momentum in South Africa, Australia (New South Wales), China, Argentina and France. The use of wild relatives in genetic engineering is growing (Khush & Baenziger 1998). The global average yield of wheat is 2.5 t/ha; the low average yield of wheat is because of large areas of wheat being under rainfed conditions. Progress in improving yield is however steady. So far, advances in yield improvement have been associated with increases in harvest index (i.e., grain-straw ratio). Further advances will depend upon greater biomass production and not merely on partitioning the phytosynthates.
At the dawn of the 21st century, we can look back with pride and satisfaction on the revolution, which farm men and women have brought about in our agricultural history during the 20th century. The Punjab farmer, hardworking, skilled and determined, has been the backbone of the revolution.
While we can and should rejoice about the past achievements of farmers, scientists, extension workers and policy makers, there is no room for complacency. We will face several new problems, of which the following are important.
Since land and water will be shrinking resources for agriculture, there is no option in the future except to produce more food and other agricultural commodities from less per capita arable land and irrigation water. In other words, the need for more food has to be met through higher yields per unit of land, water, energy and time. It would therefore be useful to examine how science can be mobilised for raising further the ceiling to biological productivity without associated ecological harm. It will be appropriate to refer to the emerging scientific progress on the farms as an evergreen revolution, to emphasise that the productivity advance is sustainable over time since it is rooted in the principles of ecology, economics, social and gender equity and employment generation.
The green revolution based on Mendelian genetics has so far helped to keep the rate of growth in food production above population growth rate. The green revolution was however, the result of public good research supported by public funds. The technologies of the emerging gene revolution based on molecular genetics in contrast, are spearheaded by proprietary science and can come under monopolistic control. How can we take the fruits of the gene revolution to the unreached? This is a challenge, which we need to address.
I would like to list 5 major challenges, which will confront the wheat scientists during this century.
The Convention on Biological Diversity (CBD) stipulates that plant exploration, collection and introduction should be based on the principles of prior informed consent and equity in benefit sharing. Therefore exchange of wheat genetic resources in the future will be possible only on the basis of Material and Knowledge Transfer Agreements.
Ecological sustainability of high productivity will be an important determinant in relation to the choice of technologies. For example, if hybrid wheat can enable us to produce 8 to 10 t/ha, over 300 kg. of nitrogen will be needed by the crop. It is obvious that if the nutrient needs of hybrid or other high-yielding wheat varieties are to be met entirely through mineral fertilizers, there will be serious environmental problems including nitrate pollution of ground water. Hence, success in achieving high productivity on a sustained basis will depend upon our ability to develop new methods of feeding the plant. Research on breeding and feeding should be carried out concurrently by a team of breeders, physiologists, agronomists and soil scientists.
There are growing public and political concerns relating to GMOs. The concerns relate to food and environmental safety and bioethics. It is essential that these concerns are carefully addressed through a mechanism for risk-benefit analysis, which inspires public confidence. An integrated disease management strategy should be developed to ensure that GMO’s with novel genetic combinations for disease resistance do not break down due to the emergence of new physiological strains of pathogens. Also, regulatory procedures should be transparent and should inspire public confidence. There is also need for integrating molecular breeding with organic farming methods.
The world is witnessing an expansion of proprietary science governed by Intellectual Property Rights (IPR). Public good research supported from public funds, in contrast, is shrinking. What will be the impact of such a situation on international varietal or other trials organised by CIMMYT? Is the golden age of cooperative research coming to an end? How can we find a balance between public good and private profit?
Will molecular breeding resulting in ‘super wheats’ lead to a high degree of genetic homogeneity in farmers’ fields? We know that genetic homogeneity will enhance genetic vulnerability to biotic and abiotic stresses. Hence, we should foster an integrated programme of pre-breeding and participatory breeding. Pre-breeding will help to generate novel genetic combinations, while participatory breeding with farm families will help to combine genetic efficiency with genetic diversity. Numerous location specific varieties can be developed in this manner. This will be the most effective way of meeting challenges arising from potential changes in temperature, precipitation and sea level as a result of global warming arising from the growing imbalance between carbon emissions and absorption.
In a predominantly agricultural country like ours, agricultural progress serves as the most effective safety net against hunger and deprivation. There is need for intensifying our efforts to improve agricultural productivity, quality and income. An urgent need in this area is the strengthening of institutional structures, which can help to confer on small and marginal farmers, the ecological and economic benefits of scale at both the production and post-harvest phases of farming. The following are some of the institutional structures whose reach has to be extended.
Without socially relevant and beneficial institutional structures, the extrapolation domain of successful experiences and development efforts will remain limited.
|
S. No |
Sector |
Institutional Mechanism |
|
1. |
Dairy |
Cooperatives |
|
2. |
Poultry |
Egg Coordination Council |
|
3. |
Integrated on-farm and off-farm employment |
Biovillages |
|
4. |
Power of scale to small producers |
Small Farmers’ Agri-business Consortium |
|
5. |
Technological upgrading of production and post-harvest sectors |
Agri-Clinics Agri-business Centres |
|
6. |
Group action for micro-enterprises supported by micro-credit |
Market-driven Self-help Groups |
|
7. |
Timely and affordable credit |
Kisan Credit Cards, Integrated Informal and Formal banking systems |
|
8. |
Operation of minimum support price |
Food corporation of India and State Food Corporations, as well as assured buy-back arrangement and contract farming by the private sector |
Dr K R Narayanan inaugurated the JRD Tata Ecotechnology Centre at the M S Swaminathan Research Foundation (MSSRF) in 1998. In the second part of my lecture, I shall briefly summarise the work done in MSSRF on issues relating to linking ecological security with food and livelihood security in a mutually reinforcing manner.
In 2005, MSSRF whose work has always received encouragement and support from Dr K R Narayanan will be completing 15 years of work in the areas of research, education, capacity building, mentoring, policy advocacy and networking. In retrospect, the decision made in 1990 to choose integrated coastal zone management for priority attention with a view to linking the ecological security of coastal areas and the livelihood security of coastal communities (both fisher and farming families) in a mutually reinforcing manner has proved to be a wise one. The Coastal System Research (CSR) programme of MSSRF was designed to give concurrent scientific attention to sea and land surfaces along the shoreline. The CSR programme was initiated in anticipation of potential adverse changes in sea level as a result of global warming. An early scientific step in this process was the conservation of mangrove genetic resources and the rehabilitation of degraded mangrove wetlands in Tamil Nadu, Andhra Pradesh, Orissa and West Bengal. Such mangrove forests served as ‘bio-shields’ during the Tsunami attack on 26 December 2004. They had also served a similar purpose during the super cyclone in Orissa in 1999. These observations have helped to generate at both the political and public levels interest in the development of bio-shields along the shoreline.
The following are among the major contributions of the CSR programme during 1990–2005.
The CSR approach helped MSSRF to propose a comprehensive and integrated strategy for launching a ‘Beyond Tsunami’ programme based on concurrent attention to ecological, livelihood, agronomic, psychological and educational rehabilitation. The experience gained by MSSRF in developing integrated coastal zone management procedures helped a National Committee set up by the Ministry of Environment and Forests under my Chairmanship to review the Coastal Regulation Zone Notification of 1991, to propose 12 basic guiding principles for the sustainable and scientific management of the Coastal Zone. Some of these are:
Based on the experience gained during the last 15 years, it is proposed to establish in Chidambaram a Resource Centre for Integrated Coastal Zone Management, for the purpose of imparting training in the erection of bio-shields, the development of biovillages and the establishment of Village Knowledge Centres. Tool Kits for these purposes have already been prepared.
In addition to the above, steps have been taken in association with the Tata Relief Committee and the World Fish Centre (ICLARM) to establish a Fish for All Training and Resource Centre at Akkarapettai village near Nagapattinam for imparting training in all aspects of capture and culture fisheries through the principle of learning by doing. The Centre will give attention to capacity building of fisher women and men in every step in the chain of capture / culture to consumption.
During 2004–05, MSSRF’s strategic and participatory research to meet the challenges of climate change, which has been so far confined to the coastal zone, was extended to the arid and semi-arid areas of Andhra Pradesh and Rajasthan with financial and technical help of the Swiss Agency for Development Cooperation (SDC) and in partnership with Action for Food Production (AFPRO) and the National Institute of Agricultural Extension Management (MANAGE). This project will help to study vulnerability to adverse changes in temperature and precipitation and develop mitigation and adaptation strategies. Such proactive measures are essential to prevent human suffering resulting from agricultural collapse during drought and flood. The climate change programme will take into account the impact of radiation, carbon dioxide concentration in the atmosphere, temperature and precipitation. It will also help to understand and chronicle traditional coping mechanisms, so that these can be conserved and strengthened. Computer simulation models on the impact of variations in temperature and precipitation will be developed and contingency plans to mitigate the adverse impact of climate change will be introduced.
Besides developing a methodology for conserving the Gulf of Mannar Biosphere Reserve for posterity through a multi-stakeholder trusteeship system of management, MSSRF has evolved during the last 15 years three other major institutional innovations in areas of significance to sustainable food and livelihood security and poverty eradication. These are described briefly below.