About 7,000 species of plants have been cultivated for consumption in human history. The great diversity of varieties resulting from human and ecosystem interaction guaranteed food for the survival and development of human populations throughout the world in spite of pests, diseases, climate fluctuations, droughts and other unexpected environmental events.
Presently, only about 30 crops provide 95% of human food energy needs, four of which (rice, wheat, maize and potato) are responsible for more than 60% of our energy intake. Due to the dependency on this relatively small number of crops for global food security, it will be crucial to maintain a high genetic diversity within these crops to deal with increasing environmental stress and to provide farmers and researchers with opportunities to breed for crops that can be cultivated under unfavorable conditions, such as drought, salinity, flooding, poor soils and extreme temperatures.
Plant genetic resources are the basis of food security and consist of diversity of seeds and planting material of traditional varieties and modern cultivars, crop wild relatives and other wild plant species. These resources are used as food, feed for domesticated animals, fibber, clothing, shelter and energy. The conservation and sustainable use of PGRFA is necessary to ensure crop production and meet growing environmental challenges and climate change. The loss of these resources or a lack of adequate linkages between conservation and their use poses a severe threat to the world’s food security in the long term. The potential of plant genetic resources for food security, sustainable livelihoods, adequate nutrition and adaptation to climate change is enormous, if managed in a sustainable manner.
Presently, only about 30 crops provide 95% of human food energy needs, four of which (rice, wheat, maize and potato) are responsible for more than 60% of our energy intake. Due to the dependency on this relatively small number of crops for global food security, it will be crucial to maintain a high genetic diversity within these crops to deal with increasing environmental stress and to provide farmers and researchers with opportunities to breed for crops that can be cultivated under unfavorable conditions, such as drought, salinity, flooding, poor soils and extreme temperatures.
Plant genetic resources are the basis of food security and consist of diversity of seeds and planting material of traditional varieties and modern cultivars, crop wild relatives and other wild plant species. These resources are used as food, feed for domesticated animals, fibber, clothing, shelter and energy. The conservation and sustainable use of PGRFA is necessary to ensure crop production and meet growing environmental challenges and climate change. The loss of these resources or a lack of adequate linkages between conservation and their use poses a severe threat to the world’s food security in the long term. The potential of plant genetic resources for food security, sustainable livelihoods, adequate nutrition and adaptation to climate change is enormous, if managed in a sustainable manner.
FAO is dedicated to improve knowledge and conservation of plant genetic resources to ensure the sustainable provision of food in the long term, and contributing to make full use of the genetic resources available, including wild relatives of main crops currently used.
The most obvious reason for maintaining plant diversity is because we rely on plants for food, and a blight that targets a major crop could have serious implications. Unfortunately, the world's major staple crops have been greatly homogenized over the years, and that's not a good thing. Many countries have lost agro-biodiversity (or the diversity of their agricultural crops), which puts the cultures and livelihoods of the poorest populations at even greater risk.
Innovative new medicines are another reason to maintain biodiversity among plants. It's a dangerous world out there and plants, being for the most part immobile, have had to evolve some particularly fiendish and unique defenses that scientists can use for medicinal purposes. Even animals, mobile creatures that they are, have had to develop some pretty potent defenses that can help scientists cook up new medicines. But in the most basic sense, the reason we need plants - along with organisms like algae and cyano-bacteria - is because they're essential for a properly functioning planet. We wouldn't even have the oxygen that we're so fond of breathing, for example, without photosynthesis.
Fortunately, conservationists had the insight to begin conserving plants in the 1950s. Some plants are maintained in their original habitats and others are held in gene banks, cell cultures and at various zoos and botanical gardens [source: FAO]. The Food and Agriculture Organization of the United Nations lists 20 major plant gene banks around the world. These banks house various types of seeds but also back up one another in the event of natural and manmade disasters.
Botanists use two methods to preserve and store a plant's genetic material. Drying and freezing seeds mimics the natural process of winter. Seeds stored by this method survive for decades. But frozen seeds must be thawed and planted to produce seeds that will grow crops. Cryonic freezing is more expensive, but it keeps stored genes "fresh" much longer than conventional drying and freezing. At cryonic temperatures, molecular action stops. Think of it as suspended animation. The frozen seed stays in the same condition, not changing or aging. The genetic seed banks around the world use these methods to store genetic and seed samples from hundreds of plants.
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