Over the decades, taste has drained out of supermarket tomatoes.

Harry J. Klee, a professor of horticultural sciences at the University of Florida, thinks he can put it back in within a couple of years.

In this week’s issue of the journal Science, Dr. Klee and his colleagues describe flavor chemicals that are deficient in most modern varieties of tomatoes. In addition, they have located genes that produce these chemicals, and identified heirloom and wild varieties of tomatoes that possess better versions of these genes.

Work has begun to breed a hybrid that restores much of the flavor yet retains the traits — large size, sturdy enough for shipping — that growers need to succeed.

“Now we know exactly what needs to be done to make it right,” Dr. Klee said. “We just have to turn the crank.”