By ALAN4DISCUSSION
Added: Fri, 15 Jul 2011 12:13:02 UTC

I think this will make an interesting topic for discussion. There is a stark contrast between the narrow selection of productive commercial food crops on which we are increasingly dependent, (with the progressive extinction of less productive but possibly more robust varieties) and the genetic diversity of natural species and historic varieties. The recent work on the potato genome and the history of the crop on the five links below provide a good example (plus one last general link on genetic diversity of food).

BBC News - Potato genome sequenced by international team. An international team has uncovered the full DNA sequence of the potato for the first time, the journal Nature reports.

EU Science News :: Potato genome sequence published - Giving more detail of the international project

That's a Potato? - Photos - Unlike the handful of varieties in U.S. markets, potatoes in Peru and Bolivia—the species' geographic center of origin—come in thousands of colors and shapes. They are so varied in flavor and nutrition that a whole diet can be built around them.

One cautionary tale about the perils of relying on a homogenous food source revolves around the humble potato. High in the Peruvian Andes, where the potato was first domesticated, farmers still grow thousands of otherworldly looking varieties. Spanish ships in the late 16th century first brought the tuber to Europe, where by the early 1800s it had become a reliable backup to cereal crops, particularly in the cold, rain-soaked soils of Ireland. The Irish were soon almost wholly dependent on the potato as their food staple. And they were planting primarily one prodigious variety, the Lumper potato, whose genetic frailty would be cruelly exposed by Phytophthora infestans, as fearsome a foe of potatoes as stem rust is of wheat. In 1845 spores of the deadly fungus began spreading across the country, destroying nearly all the Lumpers in its path. The resulting famine killed or displaced millions.

Food varieties extinction is happening all over the world—and it's happening fast. In the United States an estimated 90 percent of our historic fruit and vegetable varieties have vanished. Of the 7,000 apple varieties that were grown in the 1800s, fewer than a hundred remain.

http://ngm.nationalgeographic.com/2011/07/food-ark/food-variety-graphic

TAGGED: GENETICS