Mar 22, 2017

Variety development includes genetic approaches

Kevin Folta is eager to discuss the next big breakthroughs in genetic technology that are eventually going to lead to improvements in fruit and vegetable crops.

Folta does that regularly through his podcast (www.talkingbiotechpodcast.com), and he talked extensively on the topic as the keynote speaker at the most recent Great Lakes Fruit, Vegetable & Farm Market EXPO in Grand Rapids, Michigan.

From 2007 to 2010, Folta helped lead the project to sequence the strawberry genome, and continues to research photomorphogenesis in plants and compounds responsible for flavor in strawberries. Folta has been active as a science communicator since 2002, especially relating to biotechnology. He said he has faced controversy over his views regarding genetic technologies.

“What are the next varieties going to look like and how are we going to devise those?” asked Folta, a professor and chairman of the Horticultural Sciences Department at the University of Florida, Gainesville.

“The big breakthroughs that we’re seeing are still in facilitating traditional breeding – the way we’ve always made new crops,” he said. “The way we’re doing it now, though, is requiring what’s called genomic wide selection, where we’re able to use the information from the DNA of the organisms to select who are the best parents by sequencing individual plants.

“We’re able to put together the best plants in the beginning of the process in order to have a higher likelihood of getting offspring that have the production traits we’re looking for,” Folta said. “That’s one really big breakthrough.”

Folta said the other big development is called gene editing.

“You may have heard this referred to as CRISPR, or CRISPR/Cas9 technology,” he said.

The type II prokaryotic CRISPR/CAS (clustered regularly interspaced short palindromic repeats) has been shown to facilitate RNA-guided, site-specific DNA qualities.

“Think of this as gene editing – the ability to go into all the DNAs of a nucleus and change one base, or remove one base, or maybe add a couple,” Folta said. “The idea is to make very small, tailored, precise changes to critical genes in a plant to change them. It isn’t really this ‘GMO’ stuff. This is different. This is being able to go in and make the change, and then all the hardware that created the change goes away.”

Folta said the technology is “really nice, because it allays all of the problems people would suspect – all of the issues that we’ve had with curiosity or skepticism about genetic engineering. That’s not a problem with gene editing. It creates exactly the same thing that we get when we traditionally breed, only we know where the changes are.

“You have all of these neat new technologies that can make varieties faster, but how do we get them to the consumer the fastest and how do we see them reach their application? That’s been a problem with genetically engineered crops. We have a lot of good solutions that are still stuck on the shelf.

“What the next generation needs to do, at least the next generation of communicators, farmers and other agriculture concerns, is we need to be better at talking to consumers,” Folta said. “We need to be doing it by talking about our values – what’s important to us as scientists and agricultural producers. Why do we do what we do, and why is new technology an important part of that?

“Then we need to be meeting them with these messages in the spaces they’re in. We need to be in social media, whether we like it or not. We have to be on Facebook, Twitter, Instagram – any place where we can put a positive message about agriculture and the new technologies that are being used – we have to be there promoting it.

“When we look back at the new wave of technologies that are coming, how well they’ll be adopted is purely dependent upon how willing we are as an agricultural community to talk about it, and that’s one place where I think we can make the biggest difference,” he said.

Folta said plant genetic improvement becomes a matter of “defining the targets for consumers and breeders. It involves appealing to consumers’ senses. Psychophysics quantifies the relationships.

“The next generation of genetics starts with what we want to breed that makes sense – not doing it just because we can. We need to actually make the target a lot more evident. We need to get away from the term ‘genetically modified’ or ‘GMO.’ Use ‘genetic engineering’ in our messaging.

“The future of horticultural crop genetics is breeding. There will continue to be new breakthroughs in development, sequencing,” Folta said. “Statistics and computational techniques enable faster ‘conventional breeding.’

“What changes in DNA are always associated with a certain trait? That’s genetic selection. There’s a revolution in genomic selection. It involves the surgical dissection of a genome. It’s the same as traditional breeding, but directing where changes take place.”

There is an innovation pipeline in horticultural crops, including beta carotene- producing bananas, low acrylamide, non- browning potatoes and late blight resistance.

Folta said breakthroughs are leading to the Artic Apple (non-browning) and the BS2 tomato, in which a pepper gene eases bacterial wilt.

“We have eggplants that protect themselves from insect pests; we’ve seen grapes resistant to Pierce’s Disease, and we’re stopping citrus greening,” Folta said.

“Genetic improvement starts with the consumer; plant breeding is the best method for genetic improvement; it’s faster and more flexible,” he said.

Growing practices also play a role in how food crops are developed.

“Could controlled environments open a new niche for some specialty crops in urban centers?” he asked. “The entire process of conversion can take three to four years. This represents an opportunity for high tunnel growers to continue in the same site over longer periods of time.”

— Gary Pullano, associate editor