Reduced-Risk Pesticides and Biopesticides

Currently, many fruit crop IPM programs in Ontario rely heavily on the use of older, broad-spectrum pesticides to manage key economic pests. A growing number of reduced-risk and biopesticide alternatives are becoming available and registered for use in Canada. This document provides a brief outline and description of these categories of pesticides.

Reduced risk materials are largely defined as those materials that could result in reduced risk to human health and the environment when compared to existing alternatives. These materials exhibit one or more of the following characteristics:

• Low risk to human health
• Low toxicity to non target organisms
• Low potential to contaminate ground water, surface water or other valued environmental resources
• Broaden the adoption and effectiveness of integrated pest management strategies

The designation of reduced risk can be quite confusing. An active ingredient may be considered reduced risk on some crops and pests and not on others: Only certain "crop/pest" combinations are considered reduced risk. A list of all reduced risk and OP replacements registered for use in the US can be found at http://www.epa.gov/opprd001/workplan/completionsportrait.pdf; those available for use in Canada are listed at http://www.pmra-arla.gc.ca/english/pdf/rr/rr2005-02-e.pdf. The number of total registrations can be somewhat misleading: In the US a reduced risk use is assigned to an active ingredient/ pest combination. The Pest Management Regulatory Agency counts actual 'end-use' products in their tally.

Biopesticides are pesticides derived from natural materials (animals, plants, bacteria, minerals). While many are less toxic than conventional pesticides and pose a lower risk, others can be quite toxic. In other words: Natural does not mean non-toxic. There are three major classes of biocides: microbial pesticides, plant-incorporated protectants, and biochemical pesticides. Microbial and biochemical pesticides are applicable to fruit crop production in Ontario.

Microbial pesticides contain beneficial microorganisms (bacterium, fungus, virus or protozoan) as the active ingredient. They are relatively specific to their target pest. Microbial pesticides include the various subspecies and strains of Bacillus thuringiensis, few of which are registered in Canada.

Biochemical pesticides are naturally occurring substances that control pests by non-toxic mechanisms. Examples include insect sex pheromones used for mating disruption (note that these are synthetically produced and not "extracted" from the insects), particle film technology using kaolin clay (Surround WP Crop Protectant), and spinosyns derived from the fermentation of a soil-dwelling bacterium Sacharopolyspora spinosa (Spinosad).

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