Researcher: Stalking the Wild Tomato : Plant genetics: UC Davis scientist has roamed the world gathering material. And while his collection is in good hands, others may not be so lucky.
DAVIS, Calif. — During a nearly 50-year pursuit, Charles M. Rick slogged through Colombian swamps, scrambled across rugged terrain in Chile and Peru and made his first crossing from Ecuador to the Galapagos Islands in a boat of questionable seaworthiness.
Now white-haired and stalling retirement, Rick spends most of his days in this bucolic university town, shuttling between his jam-packed office at the University of California and nearby fields and greenhouses to tend and fine-tune the treasures of his adventures. He’s at work on an autobiographical book and may call it “Stalking the Wild Tomato.â€
In the seemingly sedate realm of agricultural research, there have always been intrepid explorer-collectors like Rick. They’ve gone to primitive villages in Africa for little-known beans, to the drought-parched soils of Ethiopia in search of coffee, to remote corners of the Philippines for rice. They have labored largely out of the public eye and certainly without the acclaim that attaches to other adventurers, tales of their exploits relegated to dry academic journals rather than heroic stories and movies of popular culture.
Rick remembers the “wooden tub,†meant for plying Ecuador’s coastal rivers, that had been lengthened three times, had no keel and a radio that worked only sporadically, yet was his only means of getting to the Galapagos in 1956. “This thing didn’t sail for two weeks after they announced the sailing date and I had plenty of time to look at that thing tied up in the docks,†he said. “The more I looked at that thing, the less I had a desire to take the trip.â€
But it’s lucky he did. Many of the materials he collected are extinct in their native environments and now exist only in his collection.
Amid the destruction of genetic diversity, the collections of Rick and other researchers are now being recognized as irreplaceable caches of conservation. Such collections store genetic information from the past that can endow tomorrow’s plants with untold improvements, resistance to diseases and pests and resilience in the face of changing environments.
Because of links to research funding, commercial interests have often determined the scope of such collections. But many scientists and conservationists worry that agribusinesses put an emphasis on collections of commercially significant food crops, such as wheat, rice and corn, while neglecting potentially valuable genes of little known or less commercially significant plants.
And even in seed banks and collections that seem healthly, the valuable contents may be slowly losing their ability to reproduce the very traits that made them valuable.
“Some of these seed banks are really seed morgues,†said Major M. Goodman, a statistical geneticist at North Carolina State University. “What goes in won’t come out alive.â€
Much of the work of tending Rick’s collection involves replanting and harvesting seeds. Those seeds are being used by researchers around the world to develop new varieties with a succession of improvements worth millions of dollars to tomato growers and processors.
Companies that distribute and process tomatoes have especially benefited from his research: Rick discovered genetic properties that code for meatiness in tomatoes, a factor that helps canners get more fruit solids and less water from each tomato; tomatoes whose genes code for thicker than average skins, a trait that helps in long-distance shipping; and tomatoes that have no crooked elbow-like stem attaching the fruit to the plant, which makes them more suited to mechanical harvesting and shipping.
Breeding lines developed from the gene that increases meatiness already have been worth about $8 million annually to tomato processors.
In many cases, the fate of a significant collection is tied to that of a single collector or researcher; sometimes when the researcher retires or dies, the collection is left to wither away on the shelves. Rick has stayed on at the university seven years past his official retirement to tend his collection.
But now, thanks to California’s Genetic Resources Conservation Program, an official curator has been hired to head a program, costing about $1 million during the next five years, to improve, maintain and staff Rick’s tomato stocks center and its collection of more than 2,500 specimens.
But there is not enough money to rescue all the endangered collections. State officials see the problem growing unless changes are made in research grant policies. They suggest that a portion of such funding grants be earmarked for long-term preservation and maintenance.
Also alarming to scientists is the sorry state of some of the world’s largest gene banks.
In 1986, the International Board on Plant Genetic Resources began a survey of some of the seed banks in its network. It evaluated 17 banks with a “base†collection--the primary storage site for seeds or other genetic materials of a vital food crop. Conditions at seven of the 17 were found unacceptable.
The world’s largest and, many say, most important bank--the National Seed Storage Laboratory at Ft. Collins, Colo.--also got the unacceptable rating.
Its problems included understaffing and poorly designed fire protection, but the most serious situation involved the inadequacy of seed sample sizes and rate of regeneration of seeds.
Adding to scientists’ concern is a growing awareness that many species of plants are unsuited to gene bank storage and that, in some instances, seeds alone are not enough to ensure preservation.
In the late 1950s, for example, Rick made several frustrating attempts to germinate seeds of tomatoes he had collected in the Galapagos Islands. He believed desirable genes of the Galapagos tomatoes could be bred into domestic tomatoes.
Traditional botany methods were of no use in trying to grow the foreign tomatoes. Many trials, including one using soil from the Galapagos and rain water, failed. Success finally came in 1960, when Rick collaborated with a colleague and two young Galapagos tortoises the colleague had brought to Berkeley a few years earlier.
In what is politely called a “rumination test,†the seeds were fed to the tortoises and retrieved after they had passed through their digestive systems. Seeds collected after 17 days and then planted had a 95% germination rate.
From Rick’s trial with the Galapagos tomatoes came not only the genes to develop the jointless tomatoes that aid harvesting, but also a reminder of the complicated weave of nature and relationships between living things that cannot be preserved in banks.
