21st March 2017
For example, most supermarket tomatoes have a genetic mutation that partially delays the production of ripening hormones, thereby adding one to two weeks of shelf life. An unintended consequence of the mutation, however, is that flavor and sugar production are also diminished. Meanwhile, when breeders selected for fruit with a uniform red color, they did not realize that the splotchy green patches on wild and heirloom varieties that they got rid of contain chloroplasts essential for sweetness and flavor production, Giovannoni says.
The new study builds on these discoveries by taking a genome-wide look at the chemistry and genetics of hundreds of tomato varieties and connecting the fruit’s chemistry with people’s preferences. The researchers also discovered that when breeders selected for larger fruits, the added girth came at the expense of sweetness: The enzymes required for sugar production got redirected toward bulking up.