story to find out more.
Garlic shoot tips (above) are immersed in
droplets of cryoprotecting solution, then plunged into liquid nitrogen to
preserve genetic diversity. Below, plant physiologist Christina Walters (left)
and technician Lisa Hill collect the seeds and label the flowers of wild-rice
plants growing in a greenhouse for a study of how their seeds develop.
Click the images for more information about them.
Preserving Wild Rice and Other Crops
By Marty Clark
April 20, 2005
Nearly half a million samples of plant
and animal germplasm are tucked away at the Agricultural Research Service's
Center for Genetic Resources Preservation in Fort Collins, Colo. But some
species do not store well using conventional storage methods.
That's where plant physiologist
Walters' team in the
Germplasm Preservation Research Unit plays an important role. Team members
find new methods to preserve samples that don't store well.
For example, wild rice seeds don't survive long and don't preserve easily.
Many breeders just stick their wild rice seeds in a refrigerator.
Walters found that the water content of seeds can be optimized to make them
neither too wet nor too dry. Some drying slows down seed aging and germination
but does not hurt the seed. Drying also means less chance that lethal freezing
will occur, so the seeds can survive at lower temperatures for longer times.
Walters' group has shown that wild-rice seeds can be stored for at least three
years at -5 degrees Celsius.
Scientists in Walters' unit are trying to solve a diverse array of
germplasm-storage problems. Some recent projects include looking at ways to
correctly identify garlic varieties--which are impossible to distinguish by
variety name, and difficult to identify by appearance--to prevent unnecessary
duplication in storage; trying to assess the genetic diversity of the
bristlecone pine, which could be one of Earth's oldest living inhabitants; and
developing new methods for storing grape germplasm.
more about the research in the April 2005 issue of Agricultural
ARS is the U.S. Department of
Agriculture's chief scientific research agency.