Biological Impacts of Transgenic Yields: Non-target Impacts in Bt Cotton.

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Bug Complex - Western U.S. Cotton. Lygus hesperus. Bemisia tabaci. Pectinophora gossypiella. Key Pests. Sporadic and Minor Pests. Cotton bollwormTobacco budwormArmywormsLoopersCotton leafperforatorSaltmarsh caterpillarCutwormsFleahoppersPlant bugsStink bugsCotton aphidThripsSpider parasites.
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Environmental Effects of Transgenic Crops: Non-target Effects in Bt Cotton This exhibits the consequences of research as it were. Specify of a restrictive item does not constitute underwriting or proposal for its utilization by USDA. Steven E. Naranjo USDA-ARS Phoenix, Arizona & Peter C. Ellsworth University of Arizona, Maricopa, Arizona

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Pest Complex - Western U.S. Cotton Key Pests Sporadic and Minor Pests Cotton bollworm Tobacco budworm Armyworms Loopers Cotton leafperforator Saltmarsh caterpillar Cutworms Fleahoppers Plant bugs Stink bugs Cotton aphid Thrips Spider vermin Pectinophora gossypiella Bemisia tabaci Lygus hesperus

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Insecticide Use Patterns Arizona Cotton Bt cotton Insect development controllers Ellsworth and Jones 2000

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Selective Insecticide Use Arizona Cotton

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Natural Enemy Complex - Western U.S. Parasitoids Predators 30+ species Hyposter Copidosoma Microplitis Lysiphlebus Chelonus Lespesia Eretmocerus Encarsia Anaphes Leiophron 50+ species Geocoris Orius Nabis Zelus Collops Hippodamia Drapetis Chrysoperla Labidura Misumenops

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Natural Enemies – Pectinophora gossypiella Predators  23 species portrayed 9 species (immunological ID) Parasitoids 4 local species depicted (uncommon) 16 intriguing species presented (0 set up)

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Function Abundance Diversity Non-Target Effects (Arthropods)

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General Methods Non-target wealth/differing qualities Replicated exploratory learns at MAC Treatments: Bt cotton/ordinary cotton Unsprayed for any bug Insecticides for all irritations as required Sampling by breadth nets , beat basins, entire plants, entanglement traps ANOVA, EstimatorS V. 5 (Colwell) for assorted qualities examinations

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Natural Enemy Abundance

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Non Bt cotton Natural Enemy Abundance No Insecticides 4530 5611 1999 0.28 0.40 0.34 0.03 0.98 0.37 0.24 0.57 0.08 0.39 2000 0.89 0.18 0.66 0.70 0.16 0.23 0.16 0.51

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Bt cotton Non-Bt Natural Enemy Abundance No Insecticides P = 0.18 P = 0.29

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Bt cotton Non-Bt Unsprayed Sprayed Natural Enemy Abundance Insecticides as Needed (e.g. 1999)

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Arthropod Community Structure

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Community Structure – Pitfall Traps (Bt versus Non-Bt) 68 70 57

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Community Structure – Pitfall Traps (Sprayed versus Unsprayed) 68 69 74 40

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Natural Enemy Function

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Methods Natural Enemy Function Replicated test learns at MAC No bug sprays Estimate rates of predation and parasitism Sentinel pink bollworm egg masses (20 for every plot) Life tables for whitefly sprites (50 for each plot)

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Natural Enemy Function Predation on Pink Bollworm Eggs

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Natural Enemy Function Mortality of Whitefly Nymphs

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Conservation Biological Control An Example Whitefly IPM in Cotton Natural Enemies Bt Cotton IGRs

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Impact of Conservation 1997

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Thanks to Virginia Barkley Kim Beimfohr Becci Burke Melanie Charney Scott Davis Ghislaine Majeau Ruben Marchosky Greg Owens Jeffrey Rivas Doug Sieglaff

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