London: Scientists have cracked and published almost all of the highly complex genetic code of wheat -- a staple food for more than a third of the world`s people -- and say breeders can now use their findings to improve yields.
The draft gene map is for a variety called Chinese Spring wheat and gives scientists and breeding companies access to 95 percent all wheat genes -- knowledge that should help them devise ways of breeding more robust and plentiful crops to meet the threat of global food shortages.
"The information we have collected will be invaluable in tackling the problem of global food shortage," said Neil Hall of Liverpool University, who is part of a British research team working on the wheat project. "We need to be breeding now what we`ll need to be eating in 10 years` time."
Wheat production worldwide is under threat from climate change and rising demand from a growing human population. World wheat prices reached a two-year high earlier this month after a record drought in Russia and crop problems in other countries.
Hall said the genome sequence data of this Chinese Spring wheat -- which scientists have chosen as a reference variety -- would allow researchers to probe differences between varieties with distinct characteristics.
"By understanding the genetic differences between varieties with different traits we can start to develop new types of wheat better able to cope with drought, salinity or able to deliver higher yields," Hall said.
Data Available Publicly
In the past, the wheat genome has been viewed as all but impossible to sequence because of its sheer size. It is made up of 17 billion base pairs of the chemicals that make up DNA -- five times more than the human genome -- so cracking wheat`s genetic code is one of the largest genome projects undertaken.
As a result, wheat is the last of the major food crops to have its genome sequenced. The gene maps of rice and maize, two other world food staples whose genetic codes are far simpler, have already been completed.
Hall said he and his colleagues had sequenced the entire wheat genome to five-fold coverage -- meaning that every single base pair has now been measured five times.
"In reality, when that is assembled it`s still fragmented -- so what it results in is a draft genome," he said in telephone interview. "But for the purposes of people involved in wheat breeding this provides the vast majority of the information they require to identify important traits."
The team used gene sequencer machines made by the Swiss pharmaceuticals firm Roche and the wheat genome data is publicly available at www.cerealsdb.uk.net .
Anthony Hall, another member of the team from Liverpool University, said some experts predict that world food production will need to be increased by 50 percent over the next 40 years to meet growing demand.
"Developing new, low input, high yielding varieties of wheat will be fundamental to meeting these goals," he said in a statement. "Using this new DNA data we will identify variation in gene networks involved in important agricultural traits such as disease resistance, drought tolerance and yield."
First Published: Friday, August 27, 2010, 13:38