Scuba rice: Building a better food from past innovations
In June of 1942, at a small beach on the French Riviera, explorer Jacques-Yves Cousteau slid on a pair of rubber fins, hitched an ungainly contraption to his back, and plunged into the water. Like no other human before him, he swam far below the surface without having to come up for air.
Cousteau is often credited with inventing scuba (self-contained underwater breathing apparatus) technology. But his advance actually came from blending existing technologies, a process that Andrew Hargadon, a professor at University of California, Davis, calls “recombinant innovation.” Cousteau started with an open-circuit, compressed-air device invented decades earlier by Yves Le Prieur. Because of its constant air flow, it could only supply air underwater for short periods. But Cousteau combined it with a regulator that had been recently developed to allow cars to run on cooking gas, as a way to cope with wartime gasoline shortages. He modified the regulator so that it released air as the diver breathed in, and scuba technology was born.
Hargadon argues that historically, some of the most effective and important technological developments and products—from electric lighting to the graphical user interface of the Windows operating system—have been pieced together in just this way, from pre-existing inventions.
Seven decades after Cousteau’s first dive, researchers at the International Rice Research Institute (IRRI) have taken a similar approach to solving a problem that could save lives and livelihoods in many parts of the world: developing flood resistant crops. The result is “scuba rice.” Named for Cousteau’s apparatus, this rice is engineered to thrive even in flooded paddies, and like his diving gear, it was created by weaving together existing innovations.
This advance could be crucial. Rice is the world’s most important food crop. Today, roughly 3 billion people count on rice for a good part of their daily sustenance, and 1 billion people are involved in its production, processing and marketing. Yet crops in many lowland locations are vulnerable to flooding. Once submerged, most rice varieties push to survive by stretching their leaves and stems toward the air. Too often, though, this effort drains their energy reserves, and they die after four or five days. With global warming lifting ocean levels, flooding threatens to depress rice production in developing countries by 15 percent in the coming decades. The all too likely result will be famine.
This grim scenario drove researchers at IRRI, a global nonprofit organization, to attempt to breed rice that could thrive underwater. In the 1990s, former IRRI scientist David Mackill, then a rice breeder at the University of California, Davis, provided one piece of the puzzle. From IRRI’s vast collection in its gene bank, he obtained a variety of rice that originated in a highly flood-prone region of Orissa, India. Mackill and his students observed that when this rice was submerged, rather than try to grow, it entered a dormant state until the water receded. Then it began to grow again. This hibernation–like response, they found, appeared to be controlled by a single gene they named SUB1.
Unfortunately, when this variety was crossed with cultivated rice, it created unappetizing hybrids. They were low yielding and nutritionally poor. Yet Mackill wasn’t working in the dark. Thanks to new genomic research, he could consult another innovation: a genetic map featuring thousands of DNA markers spread across rice’s 12 chromosomes. With funding from the Rockefeller Foundation, Mackill and his colleagues were able to use this map to identify specific DNA markers, and to trace inheritance of the SUB1 locus in progeny plants.
In 2001, Dr. Mackill moved back to IRRI as head of the lowland rice breeding programs. He combined the genetic materials and markers developed in California with IRRI’s ongoing breeding programs. In this way, he was able to move the SUB1 gene into high-yielding rice varieties targeted to the major flood prone areas of Asia, including Orissa. Collectively these varieties, which can withstand up to 20 days under water, are called scuba rice.
Scuba rice is a perfect example of an innovation that leveraged the inventions that came before it to create a revolutionary product—one that could save the lives of millions as the earth’s waters rise.