Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Thai Hill Farmers Help Preserve Genetic Diversity of Rice

31.07.2009
Traditional rice cultivation methods practiced in the isolated hillside farms of Thailand are helping preserve the genetic diversity of rice, one of the world's most important food crops, according to a new study by researchers at Washington University in St. Louis and Chiang Mai University in Thailand.

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 is also involved in science policy, serving as vice president of the National Academy of Sciences and recently appointed to the President's Council of Advisors on Science and Technology.

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.

The research, published in the Proceedings of the National Academy of Sciences, is funded by the McKnight Foundation and the Thailand Research Fund.

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.

"It's interesting to see how the expert farmers interact with the plants. For example, there was a purple mutation that occurred in one of the expert farmer's fields. He was very curious about it. He took the seeds and grew it off in a corner because he wanted to see what it looked like and tasted like. That's probably how humans domesticated plants, smart people were making smart choices in what to plant and grow," Schaal said.

Many crops grown today have been genetically optimized to consistently give a large yield. Seeds are purchased from a supplier and the plants are all genetically similar.

"Most modern varieties of crops, like corn in the Midwest or high-yield rice in the lowlands of Thailand, are artificial constructs developed by plant breeders. They are extraordinarily important in feeding the world. But they are static and not evolving in farmer's fields," Schaal said.

The rice that the Karen people grow is genetically dynamic, due to natural drift and the farmer's artificial selection. Each year, the farmers choose the seeds that grow best in their fields, which may differ in soil type, elevation, and temperature from other fields, to plant next season. Their crop is constantly evolving in response to local conditions.

"My colleagues believe that those local varieties bred within a village are better than any one single variety could be. Under these circumstances, the farmers have it right," Schaal said.

Although most agriculture in the United States focuses on growing high-yield crops to produce food for people living in cities, landraces of corn and other crops exist in seed banks.

"There is a movement among Native Americans in Arizona to grow ancestral varieties of crops. These varieties are important because they are adapted to hot and dry conditions, something that will become more prevalent as our climate changes," Schaal said.

Time will tell if those farmers "get it right" too.

Gerry Everding | Newswise Science News
Further information:
http://www.wustl.edu

More articles from Agricultural and Forestry Science:

nachricht Light green plants save nitrogen without sacrificing photosynthetic efficiency
21.11.2017 | Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign

nachricht Filling intercropping info gap
16.11.2017 | American Society of Agronomy

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New proton record: Researchers measure magnetic moment with greatest possible precision

High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons

The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Lightning, with a chance of antimatter

24.11.2017 | Earth Sciences

A huge hydrogen generator at the Earth's core-mantle boundary

24.11.2017 | Earth Sciences

Scientists find why CP El Niño is harder to predict than EP El Niño

24.11.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>