Facilitating the adoption of reduced risk approaches to pest management in apples in Ontario

Project Code: PRR09-020

Project Lead

Kelly Ciceran - Ontario Apple Growers


To facilitate the adoption of reduced risk pest management tools and approaches, for the management of insect pests in apple orchards

Summary of Results


The apple maggot (Rhagoletis mendax) and codling moth (Cydia pomonella) are significant pests affecting apple crops in many parts of Canada. When these pests feed on apples they damage the fruit, rendering them unmarketable. The apple maggot is a quarantine pest for which there is zero tolerance in many export markets, and close monitoring and continual protection of developing fruit, is required to prevent crop loss caused by both pests. In light of environmental and human health concerns regarding organophosphate (OP) insecticide use and the need for different modes of action for resistance management, a number of new insecticides have been registered for apple pests in recent years. In general, the new insecticides have different modes of action, are less persistent, and may be more pest-specific. They often target different life stages than the OPs, resulting in different application timing. Growers have been moving away from the use of organophosphates for a number of years. However OP's are still included in many orchard pest management programs. The need for education to increase grower familiarization and confidence in the use of the newer chemistries was identified through stakeholder consultations under the Agriculture and Agri-Food Canada (AAFC) Pesticide Risk Reduction’s Risk Reduction Strategy for Organophosphate Replacement in Pome Fruit.


The aim was to provide growers with the tools and knowledge they needed to advance their integrated pest management programs. The recently revised, 2009 Ontario Ministry of Agriculture, Food an Rural Affairs Integrated Pest Management Guide for Apples (Publication 310) was distributed to growers and spring workshops were held in March 2009 in the key apple growing regions of Ontario: Simcoe, Ruthven, Meaford, Colborne, and St Catharines. Trials addressing regional pest complexes were implemented in 5 apple orchards throughout the province to demonstrate the use of the pest management tools discussed in the spring workshops. Trials compared the efficacy, economics, and environmental impact of reduced risk insecticide programs in apple orchards to Integrated Pest Management (IPM) systems in which organophosphates were used.


Approximately 175 people (growers/members of agri-business) attended the spring workshops in the 5 locations. Grower feedback indicated that the information provided in the workshops was very useful. Efficacy and yield assessments in the 5 demonstration orchards indicated that the reduced risk pesticide programs were as effective as the conventional programs used by growers to manage key pests; and yields were not reduced. However, studies over additional years and under varying pest pressure are required, given the complexity of the apple orchard ecosystem.

Even though the benefits of reduced risk pesticide programs look promising, the higher cost of reduced risk pesticides continues to be a challenge for growers, especially for pests which require management over a long period of time, such as apple maggot. Crops must be protected against apple maggot from July until late August. Due to the higher number of applications required and uncertainty about the efficacy of border sprays with reduced risk products, the cost of controlling apple maggot under a reduced risk program can be 3 times more than the cost of a straight OP program. The Environmental Impact Quotient (EIQ) was used to measure the potential impact that the reduced risk and conventional pesticide programs make on the environment. In this study, in most cases, the EIQ of the reduced risk pesticide program did not differ significantly from the conventional blocks as a result of growers opting to use reduced risk pesticides in their conventional blocks.

Overall, the project provided very useful information to growers about reduced risk approaches to pest management for orchards, which increased interest in the use of reduced risk products. Grower feedback indicated that this project has increased the adoption of reduced risk pesticides through the adoption of new practices and improved spray timing. Continued work is required to incorporate the new chemistries into IPM programs in economically sustainable ways.