The quest for tastier tomatoes without GMOs

People who grow tomatoes want varieties that produce as much saleable crop as possible. People who eat tomatoes are less interested in yield, and more in taste. The tension between taste and yield can get pretty intense. What's a poor tomato plant to do?

Enter Zach Lippman, a plant geneticist from Cold Spring Harbor Laboratory in New York. "Our interest is in how we can boost productivity, yield, fruit production, without compromising any of the fruit quality traits such as size and flavor," he says.

The quality of a tomato plant's fruit is critically dependent on the interplay between the plant's need to have leaves for generating energy, and its need to have flowers and fruit for reproduction. Lippman's approach involves moderating these two competing needs using two plant proteins: florigen and its nemesis, anti-florigen.

"These two proteins are working in many ways against each other," says Lippman. "Florigen is promoting the flowering process, the transition from leaf production to flower production. Anti-florigen is repressing the transition."

By selecting plants that have different versions of the florigen and antiflorigen genes, Lippman says it's possible to optimize yield without sacrificing flavor.

As they write in the journal Nature Genetics, he and his colleagues have developed tools that make it easier for plant breeders to find plants with the optimal version of these two proteins for a particular variety of tomato. The technique doesn't involve inserting genes, as with genetically modified organisms, but rather, selecting desired genes in tomatoes.

"I think there is an immediate application for the big tomato processing industry and the fresh market industry," says Lippman.

That would be welcome news to consumers who bemoan the taste of today's supermarket tomatoes, which are largely selected for yield and ease of transport, rather than flavor.

And Lippman says there's also going to be an opportunity to produce varieties grown by the home gardener.

That day may be a ways off, however, says John W. Scott, a professor of tomato breeding and genetics at the University of Florida in Gainesville.

"This is some interesting work and may well provide yield benefits in the future," says Scott. "Work needs to be done in other labs to explore the actual potential."

Tomato lovers around the world will eagerly await the results of that exploration. Copyright 2019 NPR. To see more, visit https://www.npr.org.