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Seed conservation: cold, or dry?

Another fine guest post from Jacob van Etten.

Places with extreme conditions are good for conservation, whether it be Timbuktu with its dry, hot climate for books or Spitsbergen with its freezing cold for crop seeds. Next year the seeds will start to come to Spitsbergen from across the world to stock the “doomsday seed vault”. Right now the vault is being cooled down, to be reaching -18°C soon.

Low temperatures are key to ex situ conservation of seeds. Cold chambers and freezers stuffed with seeds are found near any plant scientist around the world. The Svalbard project is not only unique because of the size of the vault but also because of its location. The low temperatures on the island will make the vault less expensive to cool as well as less vulnerable to energy failure, a common preoccupation of seed bank managers in those countries where tropical temperatures, unreliable energy networks and unpaid bills tend to converge. An alternative solution, however, seems to be on the horizon. The latest Technology Quarterly section of The Economist runs an interesting story about dry storage of biological materials at room temperature. Wrapped in polymers or sugars, DNA molecules are less vulnerable to degeneration. Perhaps this technology will also be available to seeds some day?

Continue reading “Seed conservation: cold, or dry?”

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Three into one for new wheat

Scientists at the Australian CSIRO and Sydney University, working with colleagues at CIMMYT in Mexico, have built a chromosome that brings together the disease resistance genes of two wild wheat species into a single genetic package. 1 This should make life easier for wheat breeders; while they may be able to find valuable genes in wheat’s wild relatives, those genes are often accompanied by large blocks of other genes that often bring bad qualities. Getting the harmful genes out of the cross is apparently sometimes so difficult that breeders give up.

Thinopyrum intermedium (intermediate wheatgrass) contributed resistance to barley dwarf yellow virus, while Th. ponticum (tall wheatgrass) supplied a couple of rust resistance genes. They are both on the short arm of one of the wheat chromosomes, but without the baggage normally associated with genes from wild relatives. Crosses with bread wheats resulted in fertile offspring with the required resistance. These are being used to study the genes further in search of molecular markers that will help breeders to identify valuable crosses.

According to a press release:

By developing new DNA markers and by careful testing the team has produced a number of the disease resistance packages for wheat breeders, making it faster and easier to include these important disease resistance traits in future wheat varieties.

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Lightning strikes coconuts twice (and more)

I’m still in the Philippines, but I’ve moved from rice to coconuts. That’s in terms of what I’m discussing, not what I’m eating. I’m participating in a meeting of the curators of the five different regional components of the International Coconut Genebank, organized by COGENT. There’s a lot of interesting stuff coming out, but what I wanted to share with you now (it’s actually the afternoon tea break) is something that was shown earlier today 2 to illustrate the problems that conservation of coconuts in field genebanks can face.

The image below comes from Google Earth and shows a small piece of one of the largest and most important coconut genebanks in the world, at the Marc Delorme Research Station just outside Abidjan, Ivory Coast. Those large gaps in the otherwise beautifully laid out genebank were caused by lightning strikes! The labourers grow their cassava there now. I’d never heard of this particular threat to ex situ conserved agrobiodiversity. This particular parcel seems to have been particularly unlucky, attracting strikes repeatedly over the years.

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New pandanus poster from Pohnpei

Dr Lois Englberger of the NGO Island Food Community of Pohnpei, Federated States of Micronesia has just announced the release of a colorful new local food poster entitled “Pohnpei Pandanus:  Carotenoid-rich Varieties.” 

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Photographs and nutrient content of nine varieties of pandanus from Mwoakilloa Atoll and two varieties from Kapingamarangi Atoll are presented, along with the message that these carotenoid-rich foods can help protect against cancer, heart disease, diabetes, vitamin A deficiency and anemia or weak blood. 

The development of the poster started in 2003 with the collection of samples and arranging for analysis for provitamin A and other carotenoids, including beta-carotene, the most important of the provitamin A carotenoids.  Note that rice contains no carotenoids.

We hope that this poster may help to promote this neglected food crop, to raise awareness about the distinct varieties of pandanus and to increase understanding about the important health benefits that may be obtained by consuming this fruit.

Warm thanks are extended to the Pohnpei Cancer Coalition, Global Environmental Facility Small Grant Program, Sight and Life,  Center for Indigenous Peoples’ Nutrition and Environment, Australian Embassy, SPC GTZ Pacific German Regional Forestry Program, Pohnpei Agriculture, Pohnpei Departments of Health and Education, and the College of Micronesia-FSM for funding and other support, to the Secretariat of the Pacific Community in Suva, Fiji, for assistance in getting the poster developed, printed and laminated, and to all those assisting in this project.