Dr. Surendra Dara, Strawberry and Vegetable Crops Advisor and Affiliated IPM Advisor with University of California Cooperative Extension, has long been a proponent of incorporating biopesticides as a valuable tool in IPM programs. We caught up with him for a preview of his presentation at the upcoming Biocontrols USA 2016 Conference & Expo in Monterey, CA, March 3-4, 2016, to share some tips to help you get the best possible results with your biopesticides.
Q: What are the first things growers need to do when integrating a biopesticide into their IPM program?
Dara: It’s most important to understand the mode of action of the biopesticide and determine if it is appropriate for the pest they are concerned about. They should also choose the biopesticide based on the pest species and the life stage. This is similar to choosing a chemical pesticide depending on the pest and its life stage. For example, Bt products are generally used for lepidopteran pests; pyrethrins are used for a variety of pests; azadirachtin can be used when immature stages are present; and entomopathogenic fungi can be used against sucking pests.
Q: What should a grower look for when determining the effectiveness of a biopesticide and how soon after application, in general, should they see results?
Dara: Effectiveness of the biopesticide depends on multiple factors including time of application, combination with surfactants or other pesticides, target pests, application rates, infestation levels, and how fast control is needed. Some biopesticides can take one or more days or applications before their effect is seen. This can be similar to what you expect from some chemical pesticides.
On the other hand, a chemical insect growth regulator like novaluron and its botanical counterpart, azadirachtin, could both take a few days for their effect on target pest population because they interfere with molting.