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PESTICIDE ISSUES. “We need to recognize that pest control is basically an ecological, not a chemical problem” Robert L. Rudd (text, p. 516). To spray or not to spray…. The decision is…. ECONOMIC!. Pesticide Economics.
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PESTICIDE ISSUES “We need to recognize that pest control is basically an ecological, not a chemical problem” Robert L. Rudd (text, p. 516)
To spray or not to spray… • The decision is…. ECONOMIC!
Pesticide Economics • Economic threshold—level where economic losses caused by pest damage equal cost of applying a pesticide • Spraying beyond threshold… -can increase pest resistance and costs Ever-increasing levels? Pesticide Treadmill • Increased pesticide use (above “needed” levels) can also result from: • Spraying extra to make fruits/veggies pretty (cosmetic spraying)
INTEGRATED PEST MANAGEMENT • IntegratedPest Management (IPM) is an approach to managing pests such as insects, diseases, weeds and animals by integrating appropriate: • Physical/Cultivation • Biological • Chemical …tactics that are safe, profitable and environmentally compatible.
First Level of Pesticide Alternatives: • Cultivation practices • Crop rotation • Tree breaks/plant breaks • Polyculture—intercropping, agroforestry, polyvarietal planting • Planting “trap crops” • Genetic/Cultivated solutions—plants “resistant” to pests/diseases • BUT the pests evolve!!
http://forages.oregonstate.edu/nfgc/eo/onlineforagecurriculum/instructormaterials/availabletopics/environmentalissues/ipmhttp://forages.oregonstate.edu/nfgc/eo/onlineforagecurriculum/instructormaterials/availabletopics/environmentalissues/ipm
Biologically-based Pesticide Alternatives • Biological Solutions • Natural enemies—ladybugs, parasitic wasps What are pros and cons of this? • Good: focuses on target, self-perpetuating, minimize genetic resistance in pests • Bad: takes years of research, may be hard to mass produce, can be done incorrectly! What about introducing NON-NATIVE species??
Releasing sterilized males into the wild Both work, but costly and time-consuming on research end Developmental stops—releasing hormones into the wild to prevent an insect from developing Sex and Hormones
Chemical Methods – Two tiers First: • Naturally-occuring: Insecticidal soaps, rotenoids, Bt, cayenne pepper • Bt – bacillus thuringensis toxin from soil bacteria that is naturally toxic to many insect species. Also in GM corn Only then, as a last resort: • Conventional pesticides – Atrazine, organophosphates, carbamates (organo-chlorine compounds like DDT bioaccumulate, biomagnify and are used much less now)
Sources • http://www.scitopics.com/Integrated_Pest_Management.html • http://www.capitalgroundwater.org/h2oquiz/businesspesticide.shtml