Researchers at Johns Hopkins University and Cold Spring Harbor Laboratory have identified genes that control the size of tomatoes and eggplants, a discovery that could lead to larger, more commercially viable crops.
The findings, published in Nature and detailed in a JHU news release could help expand agricultural markets worldwide.
The study focused on the genetic mechanisms that determine how many seed cavities, or locules, develop within these fruits. By using gene-editing techniques such as CRISPR-Cas9, scientists altered specific genes to increase fruit size.
“Once you’ve done the gene editing, all it takes is one seed to start a revolution,” JHU geneticist Michael Schatz said in the release. “With the right approvals, we could mail an engineered seed to Africa or anywhere it’s needed and open up entirely new agricultural markets.”
The research is part of a broader initiative to map the genomes of 22 nightshade crops, including tomatoes, potatoes, and eggplants. The team used computational analysis to compare genome sequences and track gene evolution over time. They found that more than half of the genes examined had been duplicated at some point, a process that influences traits such as flowering time and fruit size.
In African eggplants, a species cultivated for its edible fruit and leaves, researchers identified a gene called SaetSCPL25-like, which regulates locule formation. When the gene was edited in tomatoes, the fruit developed more seed cavities, resulting in larger tomatoes.
“Having full genome sequences for these species is like having a new treasure map,” said Katharine Jenike, a researcher who helped assemble the genome sequences. “They allowed us to find size-related genes in a really unexpected place.”
By leveraging knowledge from tomato genetics, the team was able to accelerate research on African eggplants. This approach, known as pan-genetics, offers a way to enhance a wide range of crops and introduce new varieties to global markets.
“This work highlights the importance of studying multiple species together,” Schatz said. “It opens endless opportunities to bring new fruits, foods, and flavors to dinner plates around the world.”
The study was funded by the National Institutes of Health, the National Science Foundation, and the Howard Hughes Medical Institute.