Author
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Castle, Steven |
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Henneberry, Thomas |
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Submitted to: Entomology International Congress Proceedings
Publication Type: Proceedings Publication Acceptance Date: 8/1/1996 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Bemisia tabaci (SPW) as a world-wide pest has accelerated over the past 15- 20 yrs. Resistance to insecticides has been documented, although connection between identification of resistance and loss of field control has not always been clear. Other insecticide-related effects such as depredation of natural enemy populations and/or hormoligosis due to sub-lethal pesticide residues may also have contributed to outbreaks. Three consecutive years o monitoring responses of populations to insecticides failed to detect progression to higher resistance levels. Bioassay data indicated that susceptibility to most insecticides increased during this period, while insecticide field trials demonstrated good field efficacies for many insecticide treatments. Natural control has been inadequate even in organically grown crops, and there has been no indication of accelerated population growth due to hormoligosis. Populations still have grown to outbreak proportions, demanding a more comprehensive consideration of factors that contribute to outbreaks than just insecticide-related factors. The outbreak pyramid is a conceptual presentation of 4 principle components that contribute to outbreaks. A lush agricultural system in a hot, arid climate can increase populations at a rate whereby they escape their natural enemies and is beyond the economic and/or practical feasibility of management inputs to suppress populations below economically damaging levels. |
