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.
Pest, weed, and disease control
This project will help growers reduce economic losses due to witches’ broom, a problem present in all blueberry fields.
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)
The aim of this project is to determine the combined impact on fungicide efficacy of rain and the appearance of new leaves to more accurately identify how long treatments remain effective.
Researcher: Vincent Philion
The aim of this project was to test the general hypothesis that exclusion nets, when properly used, can prevent attacks by most apple pests and reduce disease incidence with no major adverse effects on fruit quality.
Researcher: Gérald Chouinard