Strawberries, blueberries, blackberries, raspberries, and… groundcherries? A little-known fruit about the size of a marble could become agriculture’s next big berry crop.
To prepare the groundcherry (Physalis pruinosa) for mainstream farming, Howard Hughes Medical Institute Investigator Zachary Lippman, Joyce Van Eck at the Boyce Thompson Institute, and colleagues combined genomics and gene editing to rapidly improve traits such as fruit size, plant shape, and flower production.
Their results show that it’s possible to take a plant that’s practically wild and bring it close to domestication in a matter of years. The team describes their work, a shortcut around traditional breeding techniques, October 1, 2018, in the journal Nature Plants.
Groundcherries (also called “husk cherries” and “strawberry tomatoes”) are native to Central and South America and it has some benefits over traditional crop – it is drought tolerant berries. They belong to a group of plants known as orphan crops. They’re grown as small-scale crops, regionally, or for subsistence. Orphan crops rarely make it into mainstream agriculture because of limitations such as poor shelf life or low productivity.
The researchers’ work lays out how genome editing can give orphan crops like the groundcherry an agricultural advantage. Scientists currently use genome editing to engineer desirable traits in mainstream crops like corn, soybeans, and many others. But until now, no one had used the technique to bolster desirable traits in orphan crops.
To ready the groundcherry for store shelves, Lippman and Van Eck needed to address some of the plant’s shortcomings. The researchers wanted to make its weedy shape more compact, its fruits larger, and its flowers more prolific. They used a three-pronged approach to tackle the problem: the team sequenced a sampling of the groundcherry’s genome, figured out how to use the genome editing tool CRISPR in the plant, and identified the genes underlying the groundcherry’s undesirable traits.
That genetic work relied on previous studies Lippman and others have already done in tomatoes. Knowing which genes control certain tomato traits let the researchers find and manipulate those same genes in the distantly related groundcherry.
Next, Lippman wants to fine-tune the groundcherry traits they have begun to improve and manipulate additional characteristics like fruit color and flavor. He notes that some traditional plant breeding will still be necessary to perfect the groundcherry as a mainstream crop. And he can’t say exactly when the fruit might make it to market. Releasing a new variety will first require navigating CRISPR intellectual property rights.
Lippman hopes his team’s work will inspire researchers to examine other orphan crops with well-studied relatives and consider how those crops, too, have potential for rapid domestication.
Zachary H. Lemmon et al, Rapid improvement of domestication traits in an orphan crop by genome editing, Nature Plants (2018). DOI: 10.1038/s41477-018-0259-x