An unfortunate and little reported side effect of last year’s Japanese earthquake and tsunami is that thousands of acres of farmland were contaminated with seawater. Rice is a staple crop in Japan, and it requires large amounts of water to grow. The salt in seawater, however, stunts or outright kills the plant. Researchers out of Riken Nishina Centre near Tokyo have been looking at the problem, and it just so happens they have a particle accelerator laying around. You can probably see where this is going.
Researchers have been working to develop a strain of rice that can tolerate salt for a number of years, but this new method could vastly improve rice agriculture. All agriculture is about nurturing desired traits in a crop; it’s just how you go about it that ruffles some feathers. Before modern science, it was a painstaking process to selectively breed plants to express the traits that make them hardier, or better for human consumption — now we can do it faster.
Genetically modified foods are becoming commonplace as we learn more about the genomes of various plants. However, for genetic modification to work, we need to know exactly what genes to manipulate. This would be fast and effective, but genes for salt-resistance are not yet well-understood in rice. That leaves researchers with the more scattershot approach of irradiation.
Mutations naturally accumulate over time (this is evolution), but this rate is far too slow for meaningful research. Past efforts in inducing mutations have relied on X-rays or gamma radiation to cause mutations in crops, but a particle accelerator should be able to accomplish the same thing much faster. Dr. Tomoko Abe is leading the research and hopes that the particle accelerator will prove superior to traditional methods. Initial results indicate this approach can produce 10-100 times more mutations.
In
her experiments, Dr. Abe exposes germinating rice seeds to a stream of
carbon ions for 30 seconds. The ions are simply atoms that have been
stripped of their electrons, and they do a real number on the rice’s
DNA. The irradiated seeds are planted in high-salt rice paddies to see
which, if any, will thrive. After bombarding 600 seeds in her particle
accelerator, Dr. Abe has created 250 mutant strains that were able to
grow in salt water and produce fertile seeds of their own.If this sounds scary, don’t get too worked up. These super-mutants aren’t the end product ready for your dinner table. The next step is to replant the most successful specimens and begin sorting out the traits that make them grow so well. Some will eventually be used for crossbreeding to concentrate the best mutations in the remaining strains. The genetic information gathered could also be used in future biotech rice products.
With enough testing, Dr. Abe hopes to be able to generate an edible strain of rice in four years that can grow in a high-salt environment. If this research is a success, the effects could reach much farther than northern Japan; there are many coastal locations around the world that could benefit from a more hearty strain of salt-resistant rice.
