Traditional Thai hill farmers help preserve genetic diversity of rice

PhysOrg.com: Rice is one of the most important crops worldwide, as it feeds over half of the world's population. Domesticated rice is an important supply of the world's rice. However, these strains are genetically static and cannot adapt to changing growing conditions. Traditional varieties, or landraces, of rice are genetically evolving and provide a pool of traits that can be tapped to improve crops worldwide.

Research from Barbara A. Schaal, Ph.D., the Mary-Dell Chilton Distinguished Professor of biology in Arts & Sciences at Washington University in St. Louis, and her colleagues at Chiang Mai University in Thailand shows how natural genetic drift and agricultural practices of the traditional farmers combine to influence the genetic diversity of a given landrace of rice.

…Schaal and her colleagues studied a landrace of rice grown by the Karen people in Thailand. They compared the genetic variation among the same variety of rice grown in different fields and villages. The genetics of the rice population fits the isolation by distance model, much like a native plant species. The further apart fields are, the more genetically distinct they are.

…In the lowlands of Thailand, farmers grow modern high-yield rice. In the hills, the Karen people practice traditional agriculture, growing ancestral varieties of rice with traditional practices. Expert farmers play a role in maintaining their crop's genetic diversity by exchanging and choosing seeds to plant the following year....

A rice plantation in Thailand, shot by Martin-Manuel Beaulne, Wikimedia Commons, under the terms of the GNU Free Documentation License, Version 1.2