October 10, 2022

CRISPR Plant Breeding Technology May Help Save Lettuce as Climate Warms

Although not yet available in the market, lettuce created from what is known as CRISPR plant breeding techniques may be the key to the continued production of lettuce as the planet warms.

California and Arizona are the two largest producers of lettuce and leafy greens making up for over 90 percent of what U.S. consumers eat. This past summer saw some of the hottest temperatures on record in California and drought continues to be a serious issue for farmers throughout the state. Arizona is always hot, which is one reason why we all enjoy lettuce in the winter.

But what will happen when climates here get even hotter? For some years now, researchers at the University of California, Davis have been working to develop varieties of lettuce that will grow in warmer climates and with less water. Traditional lettuce varieties don’t do well in warm climates, but by salvaging seeds from wild lettuce plants, breeders are hoping to develop varieties that will germinate even in hot temperatures.

A gene-editing process called CRISPR — which stands for Clustered Regular Spaced Short Palindromic Repeats —has allowed researchers to precisely improve a plant without incorporating DNA from another species.

With CRISPR, plant breeders can select specific plant characteristics for certain qualities such as higher yields, tolerance to drought, longer shelf life or better nutrition. All of this is achieved by deleting, editing or replacing specific traits working only with existing diversity of that plants’ genetic family.

In 2021, a tomato became the very first genome-edited food made with CRISPR technology to be available on the market and sold in Japan. The tomato contains high levels of gamma-aminobutyric acid (GABA), an amino acid believed to aid relaxation and help lower blood pressure.

What’s extremely beneficial about CRISPR technology, is that it allows breeders to dramatically reduce the time it takes to breed improved varieties. It is one more tool to develop sustainable solutions to ensure continued food production in the face of climate change.

Using CRISPR, scientists have the ability to improve the nutrition of some vegetables, improve animal welfare and help both plants and animals be more resistant to disease. More beneficial uses are on the horizon as well, including those developed through other gene editing techniques like Zinc Fingers, TALEN, and other methods which similarly use an enzyme to edit genes.

Because these genome-edited crops lack foreign genes, they are currently not subject to stringent regulatory approval like what is required for products. If this remains the case, developers will save millions of dollars and shave as much as 10 years from the process involved in getting a CRISPR product to market.

Even still, it will be awhile before lettuce varieties using CRISPR breeding technology will be available for sale. But with all the other concerns we have when it comes to climate change, it’s good to know that scientists are working to make sure our favorite vegetables will survive.

To learn more about how the project to develop CRISPR lettuce began, check out this video produced by the American Seed Trade Association here.