Genetic diversity
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Genetic Diversity
What is genetic diversity? Two quick definitions:
- the genetic variation present in a population or species. For example, the genetic diversity in the hundreds of varieties of potatoes can be seen by their differences in size, shape, color, taste and rate of growth.
- A property of a community of organisms of a certain species, in which members of the community have variations in their chromosomes due to a large number of slightly dissimilar ancestors; this property makes the community in general more resistant to diseases or to changing ecological conditions.
The second definition is critical to understanding the importance of genetic diversity. Variation generally makes any biological community more resistant to a pathogen or environmental fluctuation.
Seed Banks
What is a seed bank? Two quick definitions:
- A facility designed for the ex-situ conservation of individual plant samples through seed preservation and storage.
- The preservation of plant germplasm in seedbanks, (or genebanks), is one of the techniques of ex-situ conservation of plant species
Seed banks are nothing new. Nearly 5000-year-old Bronze Age communities wrapped and buried seeds in the ground, or sealed them up in huts and raised them above the ground to protect from animals, and when possible kept them cool to preserve them.
With the advance of world travel, botanical way-stations were established along the major global trade routes. As an example of their function, if coffee was being transported from Ethiopia to Europe, a botanist in transit could stop along the way at any one of a number of places established for keeping cuttings of live plants, and for seed storage. This limited form of insurance was integral to the growth of scientific botanical taxonomy through the ages.
In WW2 Leningrad, the Vavilov Institute maintained a historically notable seed collection. Vavilov was the first man to collect varieties from around the world and put them in one place, allowing breeders to use them primarily for superior crop creation. With the Nazi siege of Leningrad, the scientists of the Vavilov Institute barricaded the facility and barred entry of the countless hungry people outside who were starving. It is notable that the Vavilov scientists kept the seeds safe, and some scientists actually died of hunger, surrounded by nutritous seeds. They understood that it was important for posterity to save precious varieties. Vavilov survived the Nazi occupation but later died at the hands of Stalin who thought him a bourgoisie geneticist.
Modern seed banks were uncommon until the 1970s. After the Green Revolution inaugurated the explosion of monoculturation of a narrow variety of crops and introduced rural farmers around the world to a petrochemical-industry based economy of scale, it was understood that native varieties of crops were being lost or actually going extinct. This opened the eyes of many botanists, farmers, and researchers that the advent of the monoculturation the Green Revolution had the side-effect of marginalizing smaller-yield unhybridized varieties known as "Land Races". The growth of seed banks in this period was a direct response to this loss of Land Races.
A notable example of a modern seed bank in the news is found in Iraqi national seed bank at Abu Ghraib. The recent war led to the sacking of the national seed bank, and the unfortunate discovery of the many sample containers being emptied on the ground. Fortunately, an Iraqi scientist saved much of the seed bank variety, though in a severely diminished volume, by saving many small samples and transporting them to Aleppo, Syria before the conflict broke out. The intent is to preserve the samples now in Syria until Iraq stabilizes. In an undesirable parallel to the loss of the Abu Ghraib seed bank, Afghanistan's two principal seed banks were destroyed, their contents comingled into worthless mixtures, during that country's internal strife of 2002.
New efforts at maintaining a global seed bank are underway in Norway. There are currently 1400 seed banks around the world, and the aim is for them all to be backed up at the Norway facility, stored in the permafrost environment. In this way, if the lights go out everywhere else and stocks are lost, a backup will exist. The Norway facility is unlike many other seed banks in that it won't be for withdrawal or farm use, but primarily for backup purposes.
Sustainable Development and Genetic Diversity
What is a Sustainable Development? Three quick definitions:
- A philosophy of resource use and management intended to meet society's present needs without compromising the resource for future generations.
- Within a country or region, gradual change characterized by economic growth, increased social equity, constructive modification of ecosystems, and maintenance of the natural resource base.
- The use of components of biological diversity in a way that does not interfere with the natural functioning of ecological process and life-support systems. For example, crops that are managed in an ecologically sound way, including supporting and preserving genetic diversity for the future.
SOURCES
- grain.org - Agrofuels in Latin America
- Monoculture is harmful to the environment, because it destroys other plants and reduces biodiversity. Research into soya and sugar-cane production in Brazil shows that monoculture changes the pattern of rainfall, which becomes more concentrated at a particular period of the year and more torrential. As there is less vegetation to soak up the rainfall, it flows more quickly into the rivers or underground aquifers. Other studies show that the average temperature has been increasing and droughts are becoming more frequent in regions where monoculture prevails.
- corporateeurope.org - The EU's agrofuel folly: policy capture by corporate interests
- Yet, the negative impacts already associated with large-scale monoculture containing genetically engineered crops will be exacerbated by the large expansion of agrofuels. GM contamination is likely to increase and become more complex, when food crops are engineered with traits designed for non-food purposes.
- cropscience.org - In Defense Of Monoculture
- ABSTRACT (partial)- Because yields typically decline, crop monoculture is commonly considered as not sustainable. This yield decline is due largely to soilborne plant pathogens adapted to/specialized for the roots of the crop. For high-value fruit and vegetable crops, yields are maintained with monoculture using soil fumigation or soil solarization.
- fishinsects.suite101.com - Honeybees and Monoculture
- Single Crop Plants cover Large Areas and often Many Bees are needed. Our reliance on the Western Honeybee to pollinate many food crops inevitably exposes the bees to predators, diseases and our own attempts to control other insects.
- fishinsects.suite101.com - Colony Collapse Disorder
- Hives of Honeybees Die Without Apparent Cause. This is a worldwide problem, particularly bad in America, where honeybee colonies are dying off at an alarming rate.
- http://foodconsumer.org/7777/8888/Agri_amp_Environ_41/090606082007_Virus_linked_to_colony_collapse_disorder_in_honey_bees.shtml foodconsumer.org - Virus linked to colony collapse disorder in honey bees]
- The researchers used a technology known as termed high-throughput sequencing to sequence the genetic material from the healthy and unhealthy bees. They found one pathogen in 96 percent of samples from honey bees with CCD, but not in non-CCD colonies. The virus was the Israeli acute paralysis virus (IAPV), a discistrovirus that can be transmitted by the varroa mite.
- USDA - Germplasm and Seed Bank Resources
- Databases, Collections and Stock Centers, Germplasm Evaluation, Seed Industry and Professional Associations, Seed Suppliers, Internet Sites, Magazines, Books, Reports and Articles
- N.I. Vavilov Institute of Plant Industry
- The N.I. Vavilov Institute of Plant Industry is the only research institution in Russia whose activities include plant genetics resources (PGR) collection, conservation and study. This Institute, its accomplishments, and role in maintaining the global ex situ collection are well known world-wide. Its global PGR collection represents plant diversity encompassing 320,000 accessions of 155 botanical families, 2,532 species of 425 genera.
- NPR - Seed Banks Move to Save Threatened Species
- "I don't like to argue numbers," says Ed Guerrant, head of the Berry bank. "But it's pretty clear that biodiversity is being lost at a rate we really haven't seen since the dinosaurs."
- TheHindu - A seed bank to safeguard food supplies
- The new Svalbard International Seed Vault will serve as a repository for crucial seeds in the event of a global catastrophe, said Norway's Agriculture Minister Terje Riis-Johansen. Carved into the permafrost and rock of the remote Svalbard peninsula, it will eventually house 3 million seed samples from every country in the world.
- sciencenewsmagazine.org - Afghanistan’s Seed Banks Destroyed
- It was a looting of the worst kind—a theft of that agrarian country's stockpiled agricultural heritage. In it were seeds to help that nation's 22 million people rebuild the capacity to feed themselves.
- Consultative Group on International Agricultural Research (CGIAR) Secretariat - WORLD BANK
- The CGIAR is a strategic alliance of members, partners and international agricultural centers that mobilizes science to benefit the poor.
- International Center for Agricultural Research in the Dry Areas (ICARDA)
- With its main research station and offices based in Aleppo, Syria, ICARDA works through a network of partnerships with national, regional and international institutions, universities, non-governmental organizations and ministries in the developing world; and with advanced research institutes in industrialized countries.
- news.com - Agriculture epidemics may hold clues to Net viruses
- Computer security experts see similarities between the way a disease can devastate agricultural crops and the way a virus can attack Internet infrastructure. The reliance on one type of technology, software or protocol has created digital "monocultures," a phrase borrowed from botany that refers to ecosystems vulnerable to disastrous harm from a single disease.
GLOSSARY
genetic diversity - A property of a community of organisms of a certain species, in which members of the community have variations in their chromosomes due to a large number of slightly dissimilar ancestors; this property makes the community in general more resistant to diseases or to changing ecological conditions.
botany - Botany is the scientific study of plant life. As a branch of biology, it is also sometimes referred to as plant science(s) or plant biology. Botany covers a wide range of scientific disciplines that study the growth, reproduction, metabolism, development, diseases, and evolution of plants.
hybridization - Crossing of individuals from genetically different strains, populations, or species.
monoculture - The culture of a single species only, opposite of polyculture. Intensive cultivation of only one or two types of crops. In the short term, this method can increase production, but in the long term, it can make plants less resistant to diseases and pests, and increase the need for costly inputs.
seed bank - A facility designed for the ex-situ conservation of individual plant samples through seed preservation and storage. The preservation of plant germplasm in seedbanks, (or genebanks), is one of the techniques of ex-situ conservation of plant species.
taxonomy - The classification of organisms in an ordered system that indicates natural relationships.
Green Revolution - An agressive effort between 1950 and 1975 where agricultural scientists applied modern principles of genetics and breeding to improve crops grown primarily in less-developed countries. Sponsored by the United Nations Food and Agricultural Organisation (FAO), the effort was to increase world food production by introducing high-yield cereal varieties developed in the Philippines and Mexico.
Sustainable Development - the use of components of biological diversity in a way that does not interfere with the natural functioning of ecological process and life-support systems, for example, crops that are managed in an ecologically sound way, including supporting and preserving genetic diversity for the future
biofuels - Wood, waste, and alcohol fuels.
biogas - The gas produced from the anaerobic decomposition of organic material in a landfill.
biogenic - Produced by the actions of living organisms.
biomass - The total dry organic matter or stored energy content of living organisms that is present at a specific time in a defined unit of the Earth's surface.
biosphere - The portion of the Earth and its atmosphere that can support life. The part of the global carbon cycle that includes living organisms and biogenic organic matter.
