Plans Within Plants

Managing sheer number of samples, volume of data is focus for breeding program.

Kate Evans shows one of the program’s new seedlings and a page from the cross breeding “cull” sheets she and her staff use when moving plant material through the Washington State University pome fruit breeding system in Wenatchee, Washington, on Monday, April 23, 2018. (Photo by TJ Mullinax,  Good Fruit Grower )

Kate Evans shows one of the program’s new seedlings and a page from the cross breeding “cull” sheets she and her staff use when moving plant material through the Washington State University pome fruit breeding system in Wenatchee, Washington, on Monday, April 23, 2018. (Photo by TJ Mullinax, Good Fruit Grower)

Breeding fruit poses a monumental logistical challenge.

The plant material, traits and data points of 600 crosses and 300,000 seeds must be counted, labeled, indexed and not only stored accurately, but in a way that’s easy to find.

“One of the biggest challenges in a breeding program is just keeping track of your material,” said Kate Evans, the Washington State University apple breeder who oversees the program that released the much-hyped Cosmic Crisp.

Just take a look at her greenhouse. Tiny green seedlings stretch on tables the length of a basketball court, and that’s just from one year. More grow elsewhere at the university’s research stations and commercial trial blocks throughout the state, either making their way through a breeding journey that lasts 20 years, or waiting on standby to be used as parents.

The hunt for new varieties continues, as research technician Bonnie Schonberg uses a pencil eraser to apply pollen to the stamens of an unnamed variety at the university’s Sunrise research orchard near Wenatchee. Schonberg previously stripped and emasculated the blooms to isolate the cross pollination. (Photo by Ross Courtney,  Good Fruit Grower )

The hunt for new varieties continues, as research technician Bonnie Schonberg uses a pencil eraser to apply pollen to the stamens of an unnamed variety at the university’s Sunrise research orchard near Wenatchee. Schonberg previously stripped and emasculated the blooms to isolate the cross pollination. (Photo by Ross Courtney, Good Fruit Grower)

The breeding process all starts with the spring cross, gathering flowers in Ziploc bags from “father” trees, collecting their pollen and applying it with the eraser of a pencil to the stigma of “mother” trees — over and over again, row by row, tree by tree.

The seeds sprout in tiny pots made of irrigation pipe segments and spend the first year in the greenhouse slotted in racks of 96 because that’s how many the university’s DNA laboratory analyzes at a time. A staff member’s friend constructed them of plastic mesh especially for the breeding program.

Evans compresses the reams of data into a simple map with green or red for each rack — green for keep, red for cull. The culls are either thrown away or donated as bug food for an entomology project. Their DNA simply did not have the genetic markers of the traits the breeding program seeks.

In spite of technology, it’s all a rough guess. Evans cannot know for sure if she discards an absolute gem, the apple that would redefine apples.

“There’s never really a wow moment,” Evans said. It’s just a huge process of elimination, she said, though she prefers the term “selection.”

The seedlings that make the cut are nurtured at Willow Drive Nursery in nearby Ephrata, then grafted onto Malling 9 rootstocks in an orchard, usually Columbia View, a plot overlooking the Columbia River about 15 miles north of Wenatchee to mature for about three or four years.

Only then do they enter phase one selection based on their growth habits and fruit production. That lasts for about another three or four years. The favorable samples advance to phase two, replicated to 15 trees at three trial sites. Over the winter, Evans predicted 10 new selections would be planted for phase two this year.

Phase three gets serious, with grower evaluations, taste surveys, focus groups and storage tests. The grower-funded Washington Tree Fruit Research Commission, which funds some of the breeding program’s work, has partnered with the university to manage those phase three trials.

The whole process takes as long as 20 years. 

(Graphic by Ross Courtney and Jared Johnson,  Good Fruit Grower . Illustrations provided by WSU)

(Graphic by Ross Courtney and Jared Johnson, Good Fruit Grower. Illustrations provided by WSU)

Meanwhile, Evans keeps many of those crosses passed over in earlier phases, using them as parents for new crosses, meaning her program will continually grow. Her goal is to keep the 20-year pipeline full, so new varieties are always on the way. She does not believe any single apple, even a good one, will prop up Washington’s apple industry by itself.

So far, the university has two cultivars, known as L and M, in phase three. They are crosses of Cripps Pink and Honeycrisp, planted in commercial trials in Quincy. Evans and her team still use variety numbers internally but began publicly identifying their samples with letters to protect patent and trademark odds down the road. They predate Evans, who started in 2008.

Both varieties are tart, crisp and juicy and typically generate excitement when the university passes the apples out with survey forms at trade shows and conferences. Still, their future is far from certain. “There’s no guarantee that either of them will make it,” Evans said. But if she has her way, there will be more new apples right behind them.

Article by Ross Courtney, Good Fruit Grower

Growers get latest Cosmic Crisp horticultural tips

Stefano Mussachi, WSU tree fruit physiologist, shows growers a Cosmic Crisp apple tree in spindle tree style at the WSU Sunrise Research Orchard near Rock Island, Wash., in spring of 2016. Growers are keen on learning horticultural aspects of what the industry hopes will be a great new variety. (Photo by Dan Wheat,  Capital Press ).

Stefano Mussachi, WSU tree fruit physiologist, shows growers a Cosmic Crisp apple tree in spindle tree style at the WSU Sunrise Research Orchard near Rock Island, Wash., in spring of 2016. Growers are keen on learning horticultural aspects of what the industry hopes will be a great new variety. (Photo by Dan Wheat, Capital Press).

Washington State University tree fruit researchers shared their latest perspectives on how to grow the new Cosmic Crisp apple variety with growers at a recent field day south of Wenatchee.

ROCK ISLAND, Wash. — Mechanical pruning works well on Cosmic Crisp apple trees by the fourth year and cutting the tips of one-year old limbs controls growth better than limb bending.

Those were main points growers learned at a Washington State University field day at Sunrise Research Orchard south of Rock Island, Sept. 27.

Cosmic Crisp is the new WSU-bred apple tree the industry is starting to plant in a big way with plans for the first apples to hit grocery stores in the fall of 2019 and quickly ramp up thereafter.

Promoters say cosmic Crisp is a great eating apple with great flavor and good crispness and firmness that consumers will love more than Honeycrisp, one of its parents. It stores well without storage disorders such as water core, internal browning and superficial scald that hampers other varieties.

Perhaps it’s only negative is vigorous growth causing too much spacing between fruit, called blind wood, resulting in fruit on outer edges rather than closer to tree trunks where desired.

Stefano Musacchi, WSU tree fruit physiologist, “now believes that’s better controlled by cutting the tips of one-year-old limbs and cutting tips in subsequent years rather than by bending limbs down,” said Karen Lewis, WSU Extension tree fruit specialist. Musacchi calls it click pruning. Bending limbs down actually creates more blind wood, according to a tip sheet the scientists wrote for growers.

Apple trees produce the plant growth regulator auxin in their stems and shoot tips inhibiting bud formation. Cutting limb tips or girdling or notching every foot of a trunk on two-year-old trees interrupts auxin flow allowing more buds to form where desired.

The tip sheet gave equal credence to spindle and biaxial (two trunks off a one) tree structure for good fruit coloring and automation and mechanization of pruning and harvest while European V is more problematic for mechanized pruning and harvest.

“At the end of the day, Cosmic Crisp responds well whether vertical or angle (V),” Lewis said. “Growers need to put the math to it (what’s profitable) and their ability. They’ll do what they know.”

Musacchi is now experimenting with a fourth tree structure, what he calls top grafting which is grafting Cosmic Crisp onto stumps of other varieties above their rootstocks to develop three trunks, she said.

Lewis has focused a lot on mechanical pruning, also called hedging. Mechanical pruning in June eliminates blind wood by producing buds closer to stems and produces higher quality fruit, she said.

“We’ve also noticed that in the first couple of years when hedging the tree responds vigorously (more growth), but in the fourth year it settles down and gives you the tight narrow canopy you’re looking for,” she said. But it can result in smaller fruit which is something to consider, she said.

Article by Dan Wheat, Capital Press

Comment

Blind Renaissance

Since 1972, Blind Renaissance has an extensive history of creating the strong visual identity and cohesive media presence demanded by the sophistication of marketing environments. We design engaging, client-specific promotional materials by combining an educated artistic sensibility, knowledge of advertising trends in multiple industries and the ability to appropriately utilize new design, web and printing technology.

WSU WA 38 Field Day

Join WSU for a fall field day discussing horticulture and tips to optimize fruit quality of WA 38, WSU’s newest breeding program release. With more than 637,224 WA 38 trees in the ground already, WSU and the Washington Tree Fruit Research Commission are working hard to provide growers with the information they need to choose training systems, pruning systems, rootstocks, pollinizers, and management techniques for high quality fruit.

WA 38 Tips to Optimize Fruit Quality

September 27, 2017 @ 3:00 to 4:30 pm

WSU Sunrise Orchard, Rock Island WA

The focus of this field visit is management tips for consistently superior fruit quality. Stefano Musacchi, WSU Professor of Horticulture will demonstrate a new top grafting trial and discuss how horticulture systems impact pack out. Ines Hanrahan, Washington Tree Fruit Research Commission, will describe tips to achieve high pack outs, including how to determine optimal harvest dates, pluses and minuses of one versus two picks, and the utility of pre-harvest fungicide applications. Karen Lewis, WSU Extension will show ways to incorporate mechanization, such as hedging, in WA 38 management.

  • See the impacts of pruning, hedging and training strategies on fruit quality.
  • Learn how to use the new WA 38 starch scale.
  • Discuss management for high pack outs.
  • Taste WA 38 fruit.
  • See mechanical pruning tools.

Please note the Sept 6 field day in Prosser had to be canceled due to the later season. Fruit is not near enough to maturity for discussion.
 

Directions

WSU Sunrise Orchard, off highway 28 on Sunrise Lane, about 11 miles south of Wenatchee.