Tackling a mystery that's killing blueberries in the field

Sadie Harley
scientific editor

Andrew Zinin
lead editor

Identifying the cause and prevalence of a costly disorder in blueberries is the goal of a team of researchers at The University of Queensland.
Scientists at UQ's Queensland Alliance for Agriculture and Food Innovation are leading an investigation into root wrapping and associated crown disorders, which causes significant fruit loss globally each year.
Project lead Dr. Alice Hayward said there was little published data on the disorder and what was causing it.
"Symptoms include roots wrapping around each other or restricting the crown—where the above-ground parts of the plant meet the roots," Dr. Hayward said.
"It's an emerging problem where plants in the field are losing yield, especially under periods of high growth demand—canes or branches are dying and whole plants can die.
"We're trying to figure out the physiology of the disorder and if there are any practice changes in recent years that could be causing or amplifying it."
Blueberries are the second biggest berry industry across the world after strawberries.
In Australia, the industry had a production value of more than $505 million in 2023–2024 (Australian Horticulture Statistics Handbook 2023/24).
The QAAFI team, along with the UQ School of Agriculture and Food Sustainability, other project partners and growers Mountain Blue, Costas, and Hart's Nursery, is looking at a number of potential causes.
"Ultimately, we want to identify practice recommendations or an early screening tool that identifies if a plant is going to have problems," Dr. Hayward said.
"It doesn't look like it's a pathogen or a pest, so we are focusing on something physiological.
"We have a few hypotheses we want to test, including looking at how the blueberry is propagated and taken through the nursery process to field planting.
"We are altering practices suspected to influence the disorder.
"We'll also be looking at root and shoot architecture and measuring hormone levels to determine if that has any correlation to symptom development.
"There is heavy investment in breeding for berries, so including different genetics is also important."
The team is also hoping to better understand and quantify the extent of the problem in Australia by surveying the industry.
"We want to gather as much information as we can about how many people are affected, and what are the impacts and symptoms they're seeing," Dr. Hayward said.
More information: All blueberry growers are being invited to answer this .
Provided by University of Queensland