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CLIFF OHMART Vineyard View Biopesticides Come of Age F or as long as pesticides have been used—and particularly since the invention of synthet- ic pesticides—there has been great interest in developing ac- tive ingredients that have mini- mal impact on non-target organisms. An active ingredient in a pesticide is the ma- terial that kills the pest. The other mate- rials, inert ingredients, do not affect the pest but are in the pesticide formula to make it stable in the environment, mix well with water for spraying, etc. Finding active ingredients that do not negatively impact non-target organisms has proven to be a real challenge. Historically speaking, most of the syn- thetic pesticides that were very effective in killing pests have had significant nega- tive impacts on non-target organisms. Ex- amples are the organochlorine insecticides like DDT and the organophosphates like Lorsban and Guthion. Often their efficacy was due not only to their direct toxicity to NEW ETHANOL ASSAY AVAILABLE Also Available Potassium • Malic Acid • Acetic Acid Ammonia • Lactic Acid • Glucose/Fructose T +1 304 728 2890 E marketing@randox.com www.randox.com Randox Laboratories US Limited 60 Wines & Vines JULY 2011 the pest, but also their residual effect (they remained toxic in the environment for an extended period.) While this was great in terms of pest control, it was not so great for non-target organisms. Finding active ingredients that do not negatively impact non-target organisms has been a real challenge. As the need and demand for reduced- risk pesticides grew, the chemical indus- try responded by developing some active ingredients with much lower impacts on non-target organisms. Scientists discov- ered that certain naturally derived chemi- cals also could control pests. This class of materials became known as biopesticides, and they are playing an increasingly im- portant role in pest management. In some circles, however, their efficacy is viewed with skepticism. I thought I would devote a few paragraphs to this important class of pesticides in an attempt to clear up some misunderstandings about them. Biopesticides are naturally occur- ring chemicals or micro-organisms that control pests through various modes of action. Some people use the term biora- tionals instead of biopesticides, but as far as I can determine this is not an of- ficially recognized term. Biopesticides come in two basic classes: 1) microbials (pesticides derived from microbes), which are microorganisms such as fungi, bacte- ria, viruses, protozoans and nematodes; and 2) biochemicals such as pheromones, plant extracts that are not directly toxic to pests, or fatty acids and soaps. Microbials and biochemicals Microbials function as effective pesticides in different ways. Some microbials that are effective in controlling arthropods (e.g. in- sects, spiders and mites) produce a toxin such as Bacillus thuringiensis (Bt), which is lethal when ingested. Some bacteria and viruses are ingested by an arthropod and reproduce inside it, killing the pest through production of toxins such as nuclear poly- hedrosis viruses (NPVs). Some fungi enter Find Vineyard Supplies Suppliers Online www.winesandvinesbuyersguide.com