Keywords: biodiversity, conservation, genebanks, genetic resources, plant breeding, food security.
While biodiversity loss receives much publicity, one of its key components is disappearing almost unheralded: the genetic diversity of crops, which underpins food security and is the raw material for crop improvement. While fertiliser- and irrigation-responsive varieties led to the Green Revolution of the 1970s, a new revolution is needed to meet today’s challenges. Future agriculture must be able feed 2-3 billion more people than today while making more efficient use of fertiliser, water, energy and pesticides and this must be achieved in the face of climate change. The genetic diversity contained within traditional varieties and wild relatives makes possible the breeding the new, improved varieties that will be key to meeting these challenges. However, this diversity is threatened; changing circumstances have led many farmers to abandon their traditional crops and varieties and habitat degradation threatens many crop wild relatives. And this is occurring at a time when advances in molecular genetics make such diversity more valuable than ever. In spite of many initiatives to conserve threatened genetic resources much more is needed, for example to conserve ecosystems that are home to crop wild relatives. Many plant-collecting expeditions have been mounted in recent decades with the material collected being maintained in about 1,700 genebanks around the world, including those of the CGIAR that maintain over 700,000 accessions of important food crops. However, many collections, especially in developing countries, are themselves threatened, largely due to insufficient funding. Several important international political and institutional developments have taken place to address the situation. In 2004 the International Treaty on Plant Genetic Resources came into force as a companion agreement to the Biodiversity Convention, and the Global Crop Diversity Trust was established to provide stable, long-term funding for the world’s most valuable collections. A back-up seed repository, the Svalbard Global Seed Vault, has recently been built in the Arctic as a safety net for global seed collections and the Royal Botanical Gardens, Kew, has established the Millennium Seed Bank to store seeds of the world’s flora — many species of which are related to crops and are an invaluable source of new genes. While much remains to be done, measures such as these give hope that crop genetic diversity will remain available long into the future.
Geoffrey Hawtin, Global Crop Diversity Trust, Rome, Italy and Portesham, Dorset DT3 4ET, United Kingdom.
19 pages, 1 table, 27 references.