Despite technology, breeding desirable varieties takes time

05/08/2012 03:20:00 PM
Vicky Boyd

Being a cherry breeder is sometimes a bit like playing poker — you have to know when to hold ’em and know when to fold ’em.

Nnadozie Oraguzie, Northwest cherry breeder based at Washington State University, Prosser, was set last year to release two new sweet cherry varieties that had built-in powdery mildew resistance. However, input from an industry advisory board and field data suggested he wasn’t holding as strong a hand as he thought.

One variety had a high incidence of fruit cracking after rains, and the other produced fruit less than the threshold of 10 grams.

So Oraguzie ended up not releasing either. Instead, he said he will focus on other varieties in the pipeline that are about five years from being released.

“Considering new variety releases usually take about 15 to 20 years, I would argue we’re close because these are now in advance selection stages,” Oraguzie said.

“We’re collecting more data on those to be sure they really are (powdery mildew) resistant and the fruit quality holds up.”

Kiona, cowiche

One of the most recent releases from his breeding program is kiona, which blooms four to seven days after bing to avoid frosts but harvests six to nine days before bing.

Cowiche, a strongly flavored, large, dark red cherry that matures about four to seven days after bing, is another recent release

In addition to enhanced disease resistance, Oraguzie and his team are working to develop self-fertile varieties that don’t require a pollinizer.

Rather than devoting the typical 10% of acreage to a pollinizer, growers could plant all one variety and not have to rely as much on bees for pollination.

Oraguzie also is part of an effort to develop a stemless sweet cherry industry centered around labor-saving mechanical harvesting.

He rates every potential release for its pedicel retention force, or how easily it is removed from the stem.

Selah and skeena, for example, have low pedicel retention forces and separate easily from stems.

Faster development

Since 2010, Oraguzie and his team have used marker-assisted breeding to speed variety development.

In the past, breeders had to wait up to five years for a cherry tree to bear fruit in the field before they could evaluate it for fruit quality.

With marker-assisted breeding, they can now look for genetic markers that let them know that the plant has the desired traits long before it begins to bear fruit.

This technique doesn’t eliminate the need to plant trees in evaluation trials in Oregon and Washington, Oraguzie said.

Instead, it makes breeding more efficient and weeds out thousands of undesirable plants earlier in the process.



Comments (0) Leave a comment 

Name
e-Mail (required)
Location

Comment:

characters left

Feedback Form
Leads to Insight