The definition of integration is the act of combining several parts into a necessary whole. That’s why integrated pest management (IPM) is so important. Growers need every tool they can use to handle new or changing issues.

Talking about “Bridging the Gap Between Conventional and Biopesticides for Disease Control” at Cultivate’23 was Ann Chase, Ph.D., owner of Chase Agricultural Consulting. She began Chase Horticultural Research in 1994; the ag consulting business started in 2011, specializing in educating and consulting with growers and suppliers in ornamentals and select agricultural crops.

Chase said before you try to link conventional and control and biopesticides, you need to figure out what your motivation for doing so is. “Do you need a ‘green’ program?” she asked. “Are you looking for an improved disease prevention program?” She noted, as an example, that Fusarium has better control with biopesticides.

Pros & Cons of Biopesticides

Biopesticides are certain types of pesticides derived from such natural materials such as animals, plants, bacteria and certain minerals.

Chase noted that some benefits of biopesticides include that they generally have a shorter re-entry interval, are generally lower in residue appearance, are less likely candidates for resistance development (because they don’t have just one mode of action) and are generally safer for workers to be around.

However, there are disadvantage as well: They are generally more expensive, generally less effective and generally harder to use or place in a pest control program. Some biopesticides are alive too – and it takes effort to keep them that way.

Identify Before Taking Action

“What are you trying to prevent?” is another important question Chase asked. That’s something you need to specifically answer before adding a biopesticide to a conventional program.

She said the toughest disease challenges for biopesticides are Anthracnose, black root rot, black spot on rose, Cylindrocladium root/crown rot, downy mildew, Phytophthora aerial blight and southern blight (Sclerotium).

“If you’re dealing with these, it’s not a good place to start with a biopesticide program,” she cautioned. “There are many places to start – most of the ‘spots’ and Fusarium, for instance.”

Once you know for sure what the target it, you have to determine the best conventional and biopesticide products for that issue. When considering biopesticides, find out first if the one you’ve opted for is alive (like the Bacillus products). It’s also good to know if the biopesticide has special temperature ranges or storage conditions it needs to be kept in, or if has any sensitivity to fungicides or insecticides you’re already using.

Types of Biopesticides

Chase listed four types of biopesticides, beginning with biological control agents (BCAs). These are often living organisms used to suppress pest populations, making them less damaging than they would otherwise be, according to the Connecticut Agricultural Experiment Station. Natural enemies of insects play an important role in limiting the densities of potential pests, for example. These natural enemies include predators, parasitoids and pathogens.

One example Chase noted of a BCA is BotryStop, a biofungicide using a beneficial fungus, U. oudemansii, to compete with and control pathogenic fungal diseases. She added that Lallemand has a few BCA products, as does Obtego and RootShield Plus.

There are also BCAs that don’t need to be alive to work, such as Cease (with active ingredient Bacillus subtilis strain QST 713), Stargus, Taegro and Triathlon BA.

Certain plant extracts also work as biopesticides. Ecoswing using essential oils to keep pests away, and Regalia uses an extract from giant knotweed that causes the plants to activate an internal defense system that prevents growth of certain fungi, especially powdery mildew and gray mold, according to the EPA. Triact 70 uses Neem oil to coat fungal spores and then dehydrate them to stop the disease cycle.

There are chemical biopesticides too. Chase listed Grotto, Kalmor, Microthiol Disperse, MilStop, ZeroTol and Oxidate as proven examples.

She noted an easy way to figure out biopesticide compatibility with your current program – use the BioWorks website at

by Courtney Llewellyn