The Gene That Makes Tomatoes Sweeter Has Been Identified

On November 14th, in cooperation with domestic research institutions, the Institute of Vegetables and Flowers of the Chinese Academy of Agricultural Sciences and the Agricultural Genomics Institute of Shenzhen identified the "brake genes" CDPK27/26 that inhibit sugar accumulation in tomato fruits. Through gene knockout, the sugar content in tomato fruits can be increased by more than 30% without affecting the single fruit weight and yield per plant.

The relevant research findings were published in "Nature". Tomatoes are deeply loved by consumers for their unique flavor. Sugar content is an important factor affecting the taste of tomatoes, and most consumers prefer sweeter tomatoes. However, there is a negative correlation between sugar content and fruit size. The sugar content in existing commercial tomato varieties, especially large-fruited tomatoes, is generally low. Therefore, how to cultivate delicious tomato varieties without affecting tomato yield has always been the goal of breeding for scientific researchers.

The study found that the expression level of CDPK27/26 continuously increases during the fruit ripening process, and it promotes the degradation of sucrose synthase SUS3 through phosphorylation, thereby inhibiting the accumulation of glucose and fructose in the fruits. In the plants with the CDPK27/26 genes knocked out, the contents of glucose and fructose increased by 35% and 30% respectively. There were no significant changes in fruit size and yield per plant, but the size and number of seeds were affected to varying degrees, indicating that the photosynthetic products may have been redistributed between the fruits and seeds. The relevant research findings provide a new solution for increasing the sugar content in tomato fruits. This research was funded by projects such as the National Natural Science Foundation of China, the National Key R & D Program, the Guangdong Provincial Key R & D Program in Key Areas, and the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences.