MAY 23, 2019

The Genetic Answer to Bland Tomatoes

WRITTEN BY: Annie Lennon

Every year, the world consumes around 182 million tons of tomatoes. Yet, thanks to years of genetic editing and crossbreeding, 90% of modern, domesticated tomatoes are known for having a watery or bland taste. This may change soon however as scientists have now identified a flavor-making gene variant usually not present in cultivated tomatoes, that may help produce tastier tomatoes.

Previously, tomatoes have been selectively bred for producing desirable traits that give the most economic return. This meant that genes promoting longer shelf-life, larger yields and larger sizes were largely encouraged, while those enhancing flavor were lost or negatively selected. This resulted in today’s average supermarket tomato to both lack genetic diversity, making it more prone to disease, and flavor.

Yet, new research analyzing the tomato genome has shed new light on what influences a tomato’s taste. Researchers from Cornell University analyzed genetic data from 727 cultivated and closely related wild tomatoes. Compiling this data into a pan-genome, they then compared it to the genome of the Heinz 1706 variety of domesticated tomato, first sequenced in 2012.

This comparison revealed 4,873 previously undocumented genes. In particular, they noted that the Heinz 1706 genome was short of a rare allele, a variant of the TomLoxC, a gene that facilitates the production of a group of organic compounds known as apocarotenoids. Giving the tomato its red pigment, it is responsible for multiple fruity and floral odours, as well as the tangy flavors found in some tomatoes.

Although 90% of wild tomatoes had this gene, only 2% of older domesticated tomato varieties did. Despite this however, the allele may be making a comeback as the researchers found it present in 7% of modern tomato varieties. This may be as breeders have started to focus more on flavor than other metrics in recent decades.

To conclude, researchers hope that their findings will be considered by breeders when growing their crops. In doing so, they will not only be able produce tastier tomatoes, but also diversify their genes, building genetic resistance to diseases currently addressed by pesticides and other cost-intensive and environmentally damaging methods.

 

Sources

Smithsonian Mag 

Big Think