Ever since hunter-gatherers realized some 12 000 years ago that they could save and plant seeds from season to season, the sum of the world’s plant genetic resources for food and agriculture has been expanding. Over the millennia, farmers learned to save seeds from the crops they deemed easiest to process or store, those most likely to survive growing seasons or even those that simply tasted the best. More than 7 000 species of plants have been cultivated or collected. Many remain important to the food security of local communities. However, it is estimated that only 30 crops now provide 95 percent of human food-energy needs and just five of them – rice, wheat, maize, millet and sorghum – provide about 60 percent. Given the significance of this relatively small group of crop species to global food security, it is of pivotal importance to conserve the diversity within them – which is often immense. The number of distinct varieties of the rice species Oryza sativa is estimated to be more than 100 000. Farm communities in the Andes cultivate more than 175 locally named potato varieties. It is this within-species diversity that allows crops to be cultivated in a range of different regions, in different climates and in different types of soil.
Plant genetic diversity also has the potential to provide traits that can help meet future challenges, such as the need to adapt crops to changing climatic conditions or outbreaks of disease. A variety of Turkish wheat collected and stored in 1948 was ignored until the 1980s, when it was found to carry genes that confer resistance to many disease-causing fungi. Plant breeders now use these genes to breed wheat varieties that are resistant to a range of diseases. Wild botanical relatives of food crops – often found on the periphery of cultivated lands – may contain genes that allow them to survive under stressful conditions. These genes can add important traits, such as robustness or frost resistance, to their cultivated relatives.
Plant genetic resources for food security
African farmers felt little need for alarm when the leaves of their cassava plants occasionally became patchy. However, in 1989, an aggressive strain of cassava mosaic disease, the virus that caused the patchiness, emerged, decimating harvests throughout the Great Lakes region. In Uganda, for instance, the virus-caused food shortages led to localized famine and major economic losses.
In response, national and international experts went into action. They tested some 100 000 cassava samples collected and exchanged among gene banks from around the world. Through a process of genetic selection, they identified a series of resistant varieties and set up nurseries in the affected countries to multiply disease-free cassava seedlings – enabling the recovery of cassava cultivation.
Stemming the loss of plant genetic resources
Plant genetic diversity is threatened by “genetic erosion”, a term coined by scientists to describe the loss of individual genes and of combinations of genes, such as those found in locally adapted landraces. The main cause of genetic erosion, according to FAO’s The State of the World’s Plant Genetic Resources for Food and Agriculture, is the replacement of local varieties by modern varieties. As old varieties in farmers’ fields are replaced by newer ones, genetic erosion frequently occurs, because the genes found in the farmers’ varieties are not all contained in the modern varieties. In addition, the introduction of commercial varieties into traditional farming systems often leads to a reduction in the number of varieties grown. Other causes of genetic erosion include the emergence of new pests, weeds and diseases, environmental degradation, urbanization and land clearing through deforestation and bush fires.
Traditional efforts to counter genetic erosion concentrated on the conservation of seeds in crop gene banks (ex situ). Today, it has become clear that the best strategy combines ex situ conservation with on-the-ground (in situ) conservation, i.e. conservation of crop varieties by farmers in their local agro-ecosystems and conservation of crop wild relatives in, for example, areas protected for their environmental value.
While conserving plant genetic diversity through mechanisms of this kind is vital, sustainable utilization of plant genetic resources is also essential. Plant genetic diversity increases options and provides insurance against future problems (such as those associated with climate change). However, exploiting this potential requires the capacity to improve crop varieties through breeding. It also requires partnerships and networks that encompass all relevant stakeholders: from farmers to researchers to gene-bank managers. An integrated approach is fundamental to the development of mechanisms that will enable farming systems to adapt to future changes and meet future needs.
Encompassing all components of biodiversity for food and agriculture
In 1995, based on the increased awareness of the importance of biodiversity in achieving sustainable development, the Commission’s mandate broadened. In addition to plants, its work now encompasses all other components of biodiversity for food and agriculture – animal, aquatic, forest tree, invertebrate and micro-organism genetic resources – through its Multi-Year Programme of Work.
The Commission on Genetic Resources for Food and Agriculture
Supporting global initiatives to support crop genetic diversity
The Commission on Genetic Resources for Food and Agriculture was established in 1983 as a forum that would deal specifically with issues related to plant genetic resources. Within its mandate, the Commission has helped coordinate and guide a series of critical international initiatives that have raised awareness in the international community of the rapid increase in the erosion of plant genetic resources. It has spearheaded concerted policy-level efforts to promote conservation. The Commission developed the Genebank Standards for Plant Genetic Resources for Food and Agriculture and the International Code of Conduct for Plant Germplasm Collecting and Transfer. The Genebank Standards, which contribute to minimizing the loss of genetic diversity in ex situ collections, have been updated and expanded to cover standards for the conservation of non-orthodox seeds and vegetatively propagated plants.
The Commission keeps a watchful eye on threats to plant genetic diversity and on trends in its conservation and use by guiding periodic updates of The State of the World’s Plant Genetic Resources. As part of its Multi-Year Programme of Work, the Commission also oversees the implementation, and facilitates the updating, of the Global Plan of Action for Plant Genetic Resources for Food and Agriculture.
In 2009, at its Twelfth Regular Session, the Commission endorsed The Second Report on the State of the World’s Plant Genetic Resources for Food and Agriculture as the authoritative assessment of the sector. The second report is an update of the first report (see below) and identifies the most significant changes that occurred between 1996, when the latter was published, and 2009. It analyses the status and trends of plant genetic resources and their use, in situ management and ex situ conservation. It also addresses the state of relevant programmes, training needs and legislation at national level. It discusses regional and international collaboration in the management of plant genetic resources, taking into account the question of access to these resources and the sharing of benefits derived from their use, as well as the contributions that their sustainable use makes to food security and poverty alleviation. It also looks at the role of plant genetic diversity in sustainable agriculture and the provision of ecosystem services. For each of the main subjects addressed, the report includes an analysis of gaps and needs. The report provided the basis for the development of the Second Global Plan of Action for Plant Genetic Resources for Food and Agriculture.
In 1996, the first State of the World’s Plant Genetic Resources for Food and Agriculture was welcomed by 150 countries attending the Leipzig International Technical Conference on Plant Genetic Resources as the first comprehensive worldwide assessment of the status and use of plant genetic resource conservation. The conference also adopted the Global Plan of Action for the Conservation and Sustainable Utilization of Plant Genetic Resources for Food and Agriculture.
Building on the Global Plan of Action, work proceeded on two other groundbreaking initiatives.
- The International Treaty on Plant Genetic Resources for Food and Agriculture, negotiated by the Commission, went into effect in 2004 and has been ratified by more than 130 countries. Through the Treaty, countries agree to establish a Multilateral System to facilitate access to the genetic resources of 64 of our most important crops and forages, and to share the benefits arising from their use in a fair and equitable way. The Treaty provides for benefit sharing through exchange of information, access to and transfer of technology, and capacity-building. It also foresees a funding strategy for mobilizing funds for programmes to help, above all, small farmers in developing countries. The funding strategy also covers the sharing of the monetary benefits paid under the Multilateral System.
- The Global Crop Diversity Trust, launched in 2004, spearheads international efforts to endow the world’s most important collections of crop diversity. The Trust is an essential element of the Treaty’s funding strategy, specifically supporting the ex situ conservation of crop genetic diversity.
Building respect for minor crops and diversifying our food basket
Oca, quinoa, teff, fonio and canihua are underutilized crop species, but in certain parts of the world they are critical to household food and livelihood security. They are grains and tubers that, although conserved and used by local communities, are often overlooked by agricultural research and extension programmes. Yet, they and countless other neglected species have widespread potential to contribute to agriculture and to diet diversification, bringing benefits to farmers and consumers. The development and commercialization of underutilized crops is one of the priority activities of the Second Global Plan of Action.
The Trust, the Treaty and the Commission contribute in different but mutually supportive ways to ensuring the conservation and sustainable use of plant genetic resources.