August 29, 2010 | 9
An apple a day keeps the doctor away, but can knowing its genetic secrets help feed the nine billion people expected on this planet by 2050? Scientists hope so, especially considering they have added wheat this week to the list of crops that have had their genetic instruction set read.
Wheat, which is a grass, might seem like a simple sequencing task, but the crop actually has a genome five times bigger than a human’s three billion DNA base pairs. Scientists from the U.K. released the list of the genetics of the Chinese spring wheat variety online on August 27 in a bid to "increase the efficiency of breeding new crop varieties," said team member Keith Edwards of the University of Bristol in a statement.
Previously, agriculturists such as the late, great Norman Borlaug had to laboriously cross-breed varieties to develop new traits, such as the high-yielding dwarf wheat Borlaug bred in the mid-20th century that staved off famine for billions. Now breeders can simply focus on increasing yield under, say, the drought conditions experienced in Russia this summer. (They will be hard pressed, however, to develop a wheat variety that can withstand that country’s concomitant catastrophic fires.)
And on August 29, another team of researchers reveal in Nature Genetics the code behind the fruit that led to the fall of man (in the Judeo-Christian tradition): the apple, specifically, the Golden Delicious variety. And if the origins of the apple are to be any guide, the Garden of Eden must have been in the mountains of southern Kazakhstan, because that’s where the apple’s wild ancestors still live. And it seems to have evolved extra genetic code to survive the mass extinction event that killed the dinosaurs 60 million years ago.
Ultimately, the hope of all this genetic sequencing is to match specific genes with specific desirable traits, such as disease resistance or better taste. The Golden Delicious apple that was sequenced is distinctly less delicious than it once was thanks to modern agricultural techniques and Chinese spring wheat is not the hard red wheat that feeds much of the world, though it is closely related. But finding a roadmap to help that vital grass resist the depredations of the fungal infection known as rust, spreading again across the globe, or produce more calories on less land would go a long way to solving the world’s agricultural problems.
Image: © iStockphoto.com / Emilia Kun