Jun 13, 2012

Strawberry production strategy advances through RosBREED

I had the chance to hear three strawberry breeders speak in East Lansing, Michigan during a meeting of the RosBREED Project. RosBREED aims to improve marker-assisted breeding efforts in the Rosaceae plant family—which includes strawberries—and plays a key role in shaping modern strawberry production strategy.

One of the biggest benefits of RosBREED is the collaboration. Breeders and geneticists gather in one place, working toward common goals and sharing ideas. Jim Hancock, a professor at Michigan State University, called it “cross fertilization.”

Unlocking the strawberry genome

Tom David, a professor of plant biology and genetics at the University of New Hampshire, described himself as more of a geneticist than a breeder. His role in RosBREED is to harvest information from the strawberry genome—which his lab helped sequence—to create tools for breeders.

One of the most exciting developments he shared involves transferring wild strawberry gene into domesticated varieties. North America hold an incredible wealth of wild strawberry germplasm, with traits that can strengthen today’s crops.

“We can find wonderful things we can use right here instead of going halfway around the world,” Davis said.

In particular, he studied pigmentation traits. Cyanidin, one of the pigments responsible for strawberries’ red color, carries a much higher antioxidant potential than others.

“We’ve identified the source of genes from high cyanidin content from a strawberry that grows wild on the coast of Oregon,” he explained.

Thanks to genetic markers, breeders can now integrate traits like this into cultivated strawberries. And they ca do it much faster than in the past.

Breeding for market needs

Chad Finn, a geneticist with USDA’s Agricultural Research Service (ARS), reminded us that the strawberry industry has diverse needs. Each market requires different types of berries, and those needs drive strawberry production strategy, from fresh-market systems to processing crops.

In the Midwest and East Coast, strawberries grow mostly in perennial systems geared toward local fresh sales. In the Pacific Northwest, nearly all strawberries are grown for processing.

“We’re more interested in how they freeze and thaw in the product and how they taste in your ice cream,” Finn said.

Breeding for processing means identifying berries with strong color that retain flavor after freezing and thawing. They also need the right balance of pH and Brix. Finn admitted that it’s a tall order when you’re out in the field on a hot summer day trying to evaluate fruit.

Hopefully, with new genetic tools, breeders can select parents or seedling with desirable traits without relying solely on time-consuming, expensive field traits.

Private partnerships in strawberry breeding

Driscoll’s, the largest strawberry producer in the world, has played a major role in RosBREED. The company provided matching dollars, expertise, and berry populations for study. Many of the populations Finn works with came from overseas through Driscoll’s. Without that partnership, ARS would have sepnt significant time and money sourcing materials.

“We’re appreciative of the private partners we have,” Finn said.

Looking ahead

Listening to breeders reinforced for me how much effective strawberry production strategy depends on genetics. With tools like marker-assisted breeding and access to wild germplasm, the industry can target traits that matter—from antioxidant-rich pigments to flavor and performance in processing.

Collaboration between public researchers and private companies will keep pushing strawberry breeding forward, giving growers more options to meet diverse market demands.

By Matt Milkovich, Managing Editor