Cutting vegetables

Elizabeth Frick is speeding up vegetable breeding by means of genome editing at the KWS Gateway Research Center in St. Louis in the U.S. There have been restrictions on using the new breeding method in Europe to date. Planned changes will also benefit KWS, for example through Elizabeth’s work.

Elizabeth Frick’s scissors are minute. So tiny that they fit inside a bacterium. The cutting tool – an enzyme in liquid – is designed to penetrate a plant and sever its blueprint at a specific point. Elizabeth uses the bacterium for that. “It does the hard work and puts the scissors into the plant – and that’s when the really cool and fun part comes in,” says the Research Lead Genome Editing at the Gateway Research Center (GRC) in St. Louis. Elizabeth has given the scissors instructions as to where exactly the cut should be made. She then lets the plant grow in a petri dish for six to eight weeks. After that, she can see if the scissors have worked and the cut has had the desired effect.

Elizabeth joined KWS at the GRC two years ago. Her focus is on genome editing. “The new breeding technology is a critical part of the Strategic Planning 2035, as it will accelerate our breeding technologies and shorten our timeline to get new products with new and improved traits to the market,” says Elizabeth. As part of that, for example, she first has to find out which scissors are suitable for cutting the specific spot in the plant she’s targeting – and how the plant reacts. “A lot of it is trial and error. What makes me excited every day is to explore ways in which the process can ideally be made more cost-effective.”

She does that in collaboration with her 50 colleagues at the GRC, most of whom are involved in genome editing for different KWS crops. Colleagues using the new breeding technology were looking for cheaper alternatives to the available licensed enzymes used for cutting. However, some of these alternatives were ineffective or unsuitable for use with plants, like an enzyme that only cut at 50 degrees Celsius. Other alternatives were much more promising. “And on the recommendation of a GRC colleague, we decided to try this out on tomatoes. It actually worked. Seeing this alternative deliver results was one of my biggest wow moments so far.”

Different breeding goals

Elizabeth is responsible for tomatoes, peas and spinach at the GRC – three crops with very different requirements. The focus with peas is primarily on flavor: The objective is to make them taste better. When it comes to tomatoes, taste and disease resistance are important – as is efficiency. “Genome editing is also a tool for the breeding process itself, not just for new traits.” In the case of spinach, the task is to make it resistant to fungal diseases – because the most popular product is baby leaf spinach, which is grown several times a year. “That means fungal diseases have many opportunities to infest it, and we want to prevent that.”

Elizabeth works closely with breeders and trait scientists from Andijk to tackle all these challenges. They know what consumers demand from a vegetable variety and use this knowledge to determine which genes need to be modified in order to achieve a desired trait. Elizabeth is then tasked with implementing these requirements by means of genome editing. “For example, breeding assumes that a certain gene alters the taste. The question is then: Should it be knocked out? My job is to furnish the proof.”

The fact that Elizabeth is responsible for this task at KWS fits like the next piece of the puzzle in her résumé. “I was always interested in science. But at college, I realized I couldn’t stick a needle in anyone, so medicine was out for me.” Nor could she harm animals, as she had to in a toxicology course. She felt inspired by the many opportunities for research in the field of plants – and she liked the mindset of the people working there. That’s why she studied Plant Biology at Washington University in St. Louis. Her doctoral dissertation dealt with how plant cells under stress multiply important cell structures in order to better cope with adverse conditions. She wanted to answer this question with reference to a specific crop because “the industry is looking for people with experience.” She chose tomatoes.

After completing her doctorate, she found a postdoc position at the University of Florida and remained loyal to tomatoes. Her topic this time: Finding out which genes influence their taste. This was followed by her first job at a soybean breeding company. “My background in the field of flavor was decisive in this regard. The work in tomato breeding involved improving the taste, while soybean breeding was about eliminating it.” A job posting finally helped her find her way to KWS, just across the parking lot at the GRC. “What attracted me to KWS was its focus on genome editing.”

Genome editing in Europe

KWS opened the GRC in the U.S. 10 years ago to conduct further detailed research into genome editing. “The hands-on work in sugarbeet, for example, is carried out in Einbeck, but in Europe only greenhouse trials are possible, not field trials,” she explains. The same applies to vegetables, which were added at the GRC in 2023. Elizabeth believes concerns about genome editing are unfounded. “In mutation breeding, you have to make many changes to a plant in order to get your desired change, including ones that aren’t beneficial to the plant. With genome editing, we know exactly what we’re changing in a plant – and where.” In addition, genetic modification also takes genes from other plant species, whereas in many applications of genome editing only genes from the same species are used.

The European Commission has recognized this difference and proposed a new regulatory framework for plants derived from new genomic techniques (NGTs). Ratification by the European Council and the EU Parliament is pending, after which it will take up to two years for the implementation to be finalized and the new law to come into force. The new framework stipulates that certain NGT plants are classified as “conventional” if they meet specific scientific criteria, as such plants could also be produced using conventional breeding methods – like with genome editing.

Elizabeth believes this is an important step: Until now, genome editing in vegetables has primarily been used as a validation tool to check whether a particular gene actually has the desired effect. The expected new legislation in Europe means there is also a greater focus on marketability. “Genome editing is an important tool for developing new varieties. This benefits our customers, as we can offer improved characteristics in our varieties.” |