Apr 19, 2018

New UF blueberry variety machine-friendly

At an education session at January’s Southeast Regional Fruit and Vegetable Conference, University of Florida (UF) Assistant Professor of Blueberry Breeding and Genomics Patricio Muñoz showed a list of blueberry varieties the university has released over the years.

Those 21 blueberry varieties have many different characteristics, but one of the new releases is unlike its predecessors.

That’s a lot of new blueberry varieties! #SERFVC pic.twitter.com/oFu40cXQu7

— Fruit Growers News (@FGNews) January 12, 2018

Optimus, released in 2017, is UF’s first variety developed for machine harvesting, Muñoz said. The new variety’s name is a tongue-in-cheek reference to Optimus Prime, a robot in the Transformers movies, toys and animated TV shows.
Optimus and two other 2017 UF releases, Wayne and Magnus, have been patented, and are a few years away from commercialization. Licenses are available in 2018 to Florida nurseries.

Wayne and Magnus are named for former UF blueberry breeders Wayne Sherman, and Paul Magnus Lyrene.

The advantage of blueberries that can be harvested mechanically is that they could help U.S. growers currently dependent on labor during harvest. Muñoz anticipates large savings for growers.

“I understand very well profitability is what matters to our growers,” he said during the presentation.

Florida blueberry growers have been vocal about their competition with Mexican growers for the spring marketing window.

“Mexico realizes several cost savings benefits in the form of lower labor costs and environmental standards, which puts Florida producers at a competitive disadvantage,” the Florida Blueberry Growers Association board wrote in a 2017 letter submitted as public comment on NAFTA negotiations with Mexico and Canada.

Optimus is made for mechanical harvesting in that the fruit is able to withstand a drop from the bush into a harvester’s hopper. It’s exceptionally firm, while not crisp or crunchy, Muñoz said.

“I really like this,” he said. “It kinds of bursts in your mouth. It’s juicy.”

But breeding better berries isn’t simple, and Muñoz says there’s much work to be done.

“There are many traits that are important for machine harvesting,” Muñoz said. “It’s hard to line them up.”

Blueberry breeders, he said, hope to align a number of different traits:

• Attachment force of ripe fruit – What the breeder desires is a weak attachment of ripe berries to the bush, and a strong attachment to unripe fruit. A big differential in attachment strength could allow green berries to stay on the bush – and out of the harvest bins – while being mechanically harvested.
• Length of fruit stem – Long fruit stems are desirable so that berries are not hung up on each other and so each berry drops independently, he said.
• Architecture of the bush – “A very open cone, basically, is what we like,” Muñoz said. The conical structure allows the machine to better reach the berries.
• Scarring quality – Small, dry scars from picking-related injuries will be less susceptible to disease, he said.
• Uniform ripening – “Ideally, the more concentrated you are, the better,” Muñoz said.
• Firmness – Berries should be resistant to vertical drops and other roughness expected from machine harvesting.

Muñoz said that while UF continues to work on new varieties, the reality is the machines also should be improved. Watching a mechanical harvester sling berries around makes him wince.

“I was suffering when I was seeing that fruit bouncing all the way up on the machine. We need improvement in the technology that we are using,” Muñoz said. “Hopefully that’s coming, because that fruit is suffering there.”

– Stephen Kloosterman, FGN Assistant Editor

Above: University blueberry bushes during February, when the University of Florida conducts its breeding trials. Photo: University of Florida Blueberry Breeding Program