New Seed Banks for biodiversity

Evolutionary biologists recognize that the gene pool of any species is a dynamic resource that changes over time as a result of random events such as highly destructive climatic events like hurricanes, but also through sustained and ongoing processes like evolution by natural selection.
While most scientists agree that the climate is changing, the extent to which species will be able to evolve to keep up with these changes is unknown.

Repeatedly sampling the gene pool of plants held at seed banks to  compare the attributes of the gene pools that are sampled at different times to a baseline.
Then comparing the genetics of the DNA from seeds that collected on an annual or some periodic basis would allow scientists to see the effect of various changes on any given plant population over time. At present scientists don’t know whether or not the environmental changes that are ongoing, due to changes in climate or land use practices, are reducing the amount of genetic variation in the wild. If they are, the only way it can be detected will be by sampling representative seeds from a large number of populations at very regular intervals.

This approach will allow a number of things that a one-time, seed-sampling event doesn’t.  First scientists can evaluate the impact of the effects of climate change, land use change, and other kinds of environmental changes such as the spread of disease on the gene pool.

Second seed banks now focus on species that have been under cultivation for a long period which decreases genetic variation because their genes are being manipulated to produce certain traits. Wild plant species show a high degree of genetic diversity in most traits which is the natural way plants can adapt to environmental changes over time.

“The approach that we would use is not simply to collect seeds over various time intervals and to archive them, but in the future to raise them in a common environment comparing seeds that were collected in 2010, 2030, and 2050, for example,” said Mazer. “If we found, for example, that the plants that come from seeds that were collected 50 years from now flower much earlier than those that were collected today, we could logically infer that natural selection over 50 years had favored plants, that is genotypes that flowered earlier and earlier, relative to those that delayed flowering.” This would be a new type of seed bank focused the  importance of recording adaptive changes plants are making over time.

On the other hand the value of Svalbard Global Seed Vault, on the island of Spitsbergen in Norway planning to preserve hundreds of thousands of varieties of agricultural plant species, but most of those samples represent only a tiny fraction of that which you would find in a wild population of a wild species. Both types of seed banks are needed.
October 17, 2008, For more information: http://www.sciencedaily.com/releases/2008/10/081015144135.htm
seed images: http://search.live.com/images/results.aspx?q=Seeds&FORM=QSIR16

and at http://en.wikipedia.org

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