The U.K. journalist Miles Kington quipped that knowledge is knowing a tomato is a fruit; wisdom is knowing not to put one in a fruit salad. It wasn’t always this way. Decades of commercial growing have altered the tomato’s genetic makeup, turning it from a once-sweet fruit into today’s relatively tasteless sandwich topper. Now, a new study has uncovered which flavor-enhancing genes have been lost, giving growers a “roadmap” to breed tastiness back into their tomatoes.
“This is great work, which I believe could only be done by very few groups on Earth,” says Changbin Chen, a horticultural scientist at the University of Minnesota in St. Paul, who wasn’t involved with the study. “This is doable for commercial growers who supply the fresh tomato market.”
Tomatoes are among the highest-value crops in the world. In the United States—the world’s second largest tomato grower behind China—they account for more than a billion dollars in sales annually. Nutritionally, they are important sources of vitamins A and C. But the large, plump, ruddy tomatoes available year-round in grocery stores taste much different than the small, multihued, berry-sized fruits that evolved more than 50 million years ago near Antarctica and were first domesticated in Central and South America some 2500 years ago. The fruits spread throughout the world following Spanish colonization in the 16th century. Over the next 400 years or so, hundreds of regional cultivars of tomatoes emerged, but they mostly stayed small, sweet, and flavorful.
Then, commercial agriculture exploded after World War II, and tomato crops were bred for higher yields, disease resistance, redder color, and firmness, explains Harry Klee, a horticultural scientist at the University of Florida in Gainesville and one of the study’s authors. These traits helped growers sell their crops for more money, but growers neglected genes responsible for taste, Klee says, and many of these were lost or tamped down over thousands of generations.