September 13, 2005
By Zhang Jun,
English.eastday.com via
Checkbiotech
A group of local scientists
announced yesterday they have found and cloned a key genetic
code in rice that is responsible for salt-tolerance - a
breakthrough that could eventually lead to higher yields.
The group's findings were
published on the online version of "Nature
Genetics" - a UK-based scientific journal - on Sunday and
the print issue will be published next month, scientists said.
"Hopefully, our research can speed up the country's development
of high-yielding rice species," said Lin Hongxuan, a professor
at the Shanghai Institute of
Plant Physiology and Ecology - an arm of the Chinese Academy
of Sciences.
Funded by both the central and Shanghai governments, Lin and
more than 13 researchers and students spent the past five years
completing the project, which they say is a key achievement in
the country's agricultural development.
The group was also supported by researchers from the University
of California. During the past five years, Lin and his
companions traced the genetic material in six generations of a
specially grown hybrid rice.
Each generation took around half a year to grow, Lin said.
By a technique called "precise location," they finally found and
cloned the SKC1 gene, which is responsible for salt-tolerance in
rice.
Lin said soil with a high salt content can severely affect rice
yields, particularly in some coastal areas and the country's
northwest regions. Under extreme conditions, it can even reduce
rice yields by more than 50 percent.
"Normally, it will take several years for agricultural experts
to utilize the discovered gene to optimize rice species and to
lift rice yields," Lin said.
He said it might be possible to use the breakthrough to create a
genetically modified species of rice.
As the most important grain crop, rice sustains half of the
world's population. Improving yields could solve world hunger
problems.
According to Wang Guozhong, head of the Shanghai Agricultural
Technology Service Center, the discovery will speed up efforts
to lift rice yields in the country, although high salt levels
aren't a problem for local farmers.
"The discovery is very enlightening and will help farmers
increase rice yields in rural areas," he said.
Copyright
English.eastday.com
Related article
Gene for salt tolerance found in rice
Jia Hepeng,
SciDev.Net
Researchers in China and the United States have identified a
rice gene linked to salt tolerance, raising hopes of improving
the ability of Asia's most important crop to grow in saline
soils.This discovery
could have tremendous significance for China's food security
because approximately eight per cent of its rice fields have
high levels of salt, says lead researcher Lin Hongxuan of the
Shanghai Institute for Biological Sciences.
In 2001, another group of
Chinese researchers developed genetically modified salt-tolerant
rice, which is currently undergoing field trials.
But Lin points out that the
rice developed by those researchers contains genes from other
species. But the gene Lin's group identified — SKC1 — occurs
naturally in a variety of Japanese rice called Nona Bokra.
Having a
naturally occurring gene for salt tolerance means it should be
possible for researchers to develop new salt-tolerant rice
varieties using either traditional breeding or genetic
engineering techniques.
The SKC1 gene controls the
amount of sodium — a component of salt — that builds up in rice
plants as they grow. Too much sodium is detrimental to plant
growth.
Lin's team used genetic
engineering methods to insert the gene into a rice variety with
low salt tolerance. The sodium concentration in the modified
plants fell by 25-30 per cent.
"Meanwhile,
SKC1 improved the concentration of the mineral potassium by 20
per cent, which is beneficial for rice growth," Lin told
SciDev.Net.
"But more work, such as testing
how SKC1 interacts with other genes, must be done before this
gene can be used to develop a new salt-tolerant rice variety,"
Lin adds.
Lin's team, from the Shanghai
Institute for Biological Sciences, the Chinese Academy of
Sciences and the US-based University of California at Berkeley,
published their findings online in Nature Genetics,
11 September. The paper will also appear in October's print
edition of the journal.
Link to abstract of paper in
Nature Genetics:
www.nature.com/ng/journal/vaop/ncurrent/abs/ng1643.html
Reference: Nature Genetics doi:10.1038/ng1643 |