Detecting spores of Pucciniastrum geopertianum, the fungus that causes blueberry witches’ broom rust

Richard Hogue, researcher

Richard Hogue

Researcher

418 643-2380
ext 420

Contact Richard Hogue

Description

Witches’ broom is a recurring problem in in all highbush blueberry fields. It was particularly widespread in 2016. However in Québec the disease has never been found on the witches’ brooms themselves. The brooms are just a symptom. According to the literature, the disease is probably caused by a rust fungus. Rusts are peculiar in that they complete their life cycle on two separate hosts.  In the case of witches’ broom rust, the hosts are highbush blueberry and balsam fir. In balsam fir, the disease causes needle rust. The spores are often observed in July, but the beginning and end of the sporulation period has not been determined in Québec. Witches’ broom rust causes economic loss in both these hosts. The aim of the project was to determine whether the witches’ broom symptom on blueberries is really caused by the rust Pucciniastrum geopertianum, which attacks balsam.

Objective(s)

  • Using PCR tests and isolation on agar plates, study the symptom chronology of the rust caused by P. geopertianum, which grows on balsam fir and blueberries, by testing weekly samples of balsam needles and blueberry witches’ brooms throughout the season
  • Determine sporulation start and end dates on each host
  • Identify fungi in samples using PCR testing
  • Determine whether the disease can be spread from one blueberry field to another

2016

Project duration

Fruit production

Activity areas

Pest, weed, and disease control

Service

This project will help growers reduce economic losses due to witches’ broom, a problem present in all blueberry fields.

Partners

Ministère de l'Agriculture, des Pêcheries et de l'Alimentation du Québec | Appui au développement de l'agriculture et de l'agroalimentaire en région (PADAAR)

This may interest you

Fire blight infection
2015-2018 • Fruit production

Distribution of the infection period required by individual ascospores of Venturia inaequalis

Improving the RIMpro software to better predict the risk of infection during rainfall.

Researcher: Vincent Philion

Read more about the project

Vincent Philion
Blueberries
2015-2019 • Fruit production

Sound water management for lowbush blueberries under fluctuating and changing climatic conditions

Using sound irrigation management to control frost and water stress in lowbush blueberry helps stabilize yield while minimizing environmental impacts.

Researcher: Carl Boivin

Read more about the project

Carl Boivin
Lowbush blueberries
2017-2018 • Fruit production

Exploring the potential of thermal imaging data acquired by drone for the detection of water stress in lowbush blueberries

Exploration of the potential of detecting water stress in lowbush blueberries using a thermal infrared imaging sensor installed on a drone.

Researcher: Carl Boivin

Read more about the project

Carl Boivin