Biopesticides

western tarnished plant bug (Lygus hesperus) killed by the entomopathogenic fungus, Beauveria bassiana, photo credit: Surendra Dara, University of California, Agriculture and Natural Resources

Generally, biopesticides are made of living things, come from living things, or they are found in nature. They tend to pose fewer risks than conventional chemicals. Very small quantities can be effective and they tend to break down more quickly, which means less pollution.

Some biopesticides are targeted in their activity, often working on a small number of species. However, users need more knowledge to use biopesticides effectively. This is because they are often most effectively used as part of an Integrated Pest Management approach.

Types of biopesticides:

Microbes - These are tiny organisms like bacteria and fungi. They tend to be more targeted in their activity than conventional chemicals. For example, a certain fungus might control certain weeds, and another fungus might control certain insects. The most common microbial biopesticide is Bacillus thuringiensis.
Substances Found in Nature – These include plant materials like corn gluten, garlic oil, and black pepper. These also include insect hormones that regulate mating, molting, and food-finding behaviors. They tend to control pests without killing them. For example, they might repel pests, disrupt their mating, or stunt their growth. Some synthethic substances are allowed. However, they must be similar in shape and makeup to their natural counterparts. They must also work in the exact same way against pests.
Plant-Incorporated Protectants (PIPs) – These are the genes and proteins, which are introduced into plants by genetic engineering. They allow the genetically modified plant to protect itself from pests, like certain insects or viruses. For example, some plants produce insect-killing proteins within their tissues. They can do this because genes from Bacillus thuringiensis were inserted into the plant’s DNA. Different types of proteins target different types of insects.

Biopesticide information from NPIC: Bt, citronella oil, neem oil, iron phosphate, methoprene, capsaicin, copper sulfate (possible biopesticides: pyrethrins, spinosad, boric acid)

If you have questions about this, or any pesticide-related topic, please call NPIC at 800-858-7378 (8:00am - 12:00pm PST), or email us at npic@ace.orst.edu.

Additional Resources:

What are Biopesticides? - Environmental Protection Agency (EPA)
Biopesticide Active Ingredients - Environmental Protection Agency (EPA)
Regulating Biopesticides - Environmental Protection Agency (EPA)
Biopesticide and Organic Database for IPM - IR-4 Project, NC State University
Pesticide Registration Manual: Chapter 3 - Additional Considerations for Biopesticide Products - Environmental Protection Agency (EPA)
Biopesticide Registration Tools - Environmental Protection Agency (EPA)
Alternative Pesticide Options for The Home Gardener - University of Arizona Cooperative Extension (This publication is not a recommendation and provides examples only)
Where can I find more information on biopesticides? - Environmental Protection Agency (EPA)

Last updated April 14, 2022

Related Topics:

What are pests?

What are pesticides?