Study and management of summer diseases of apples

Lead Applicant: Katerina Jordan

Research Priority: Plant Health & Protection

Program Type: Tier 1

Funding Cycle: 2023/2024

Research Centre: Ontario Crops Research Centre – Simcoe

Research Summary: Summer diseases of apples such as bitter rot and black rot (frogeye leafspot) are becoming more prevalent in Ontario orchards. Bitter rot was not even a concern in Ontario before 2010 but climate change has contributed to the increased incidence of both diseases. Bitter rot is caused by many species in the Colletotrichum genus, and although the predominant pathogen in Ontario is C. fioriniae, our recent results show the presence of more species in Ontario orchards. These species could vary in their response to fungicides; therefore, this is the best time to determine more species involved and to craft management strategies for apple growers. A discussion with OMAFRA specialists also indicated sector needs to manage black rot on younger apple trees. This proposal will investigate potential bio fungicides to control these pests in efficacy trials. The project will provide more tools and knowledge for apple growers to manage these diseases.