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ARS Home » Pacific West Area » Maricopa, Arizona » U.S. Arid Land Agricultural Research Center » Pest Management and Biocontrol Research » Research » Publications at this Location » Publication #308218

Title: Save money the easy way with bio-control

Author
item VANDERVOET, T - University Of Arizona
item ELLSWORTH, P - University Of Arizona
item Naranjo, Steven
item BROWN, L - University Of Arizona
item FOURNIER, A - University Of Arizona

Submitted to: University of Arizona Cooperative Extension
Publication Type: Other
Publication Acceptance Date: 8/6/2014
Publication Date: 8/8/2014
Citation: Vandervoet, T., Ellsworth, P.C., Naranjo, S.E., Brown, L., Fournier, A. 2014. Save money the easy way with bio-control. University of Arizona Cooperative Extension. 08/2014.

Interpretive Summary: Sweet potato whitefly is a key insect pests affecting cotton and many other agronomic and horticultural crops in the southwestern U.S. Prior research has shown that arthropod natural enemies, particularly predators, can have a significant impact on whitefly population dynamics and can regulate populations of this pest under certain conditions. The cotton integrated pest management (IPM) program in Arizona is well established and has been deployed for many years in Arizona and a number of other U.S. states and countries. It depends on careful monitoring of whitefly abundance and adherence to economic thresholds to determine the need to apply remedial insecticides. When insecticides are applied, growers are encouraged to use selective options that do not harm the natural enemy complex. This extension circular describes the research behind a new approach to whitefly management that takes into account not only whitefly abundance but also the abundance and activity of 4 key predator species commonly found in cotton. For each predator we estimated a predator to prey (whitefly) ratios that can be used to decide when additional control actions are warranted. When the ratio is high control actions can be delayed; when the ratio is low it is likely that control actions are necessary. Ratios in between these levels requires careful consideration of the relative abundance of predators and whiteflies. A companion circular describes how to determine the abundance of both whiteflies and predators and how to use ratios for decision-making. The approach should not only reduce the need for insecticide applications but also reduce the risk to growers from pest insect losses.

Technical Abstract: Sweet potato whitefly is a key insect pests affecting cotton and many other agronomic and horticultural crops in the southwestern U.S. Prior research has shown that arthropod natural enemies, particularly predators, can have a significant impact on whitefly population dynamics and can regulate populations of this pest under certain conditions. The cotton integrated pest management (IPM) program in Arizona is well established and has been deployed for many years in Arizona and a number of other U.S. states and countries. It depends on careful monitoring of whitefly abundance and adherence to economic thresholds to determine the need to apply remedial insecticides. When insecticides are applied, growers are encouraged to use selective options that do not harm the natural enemy complex. This extension circular describes the research behind a new approach to whitefly management that takes into account not only whitefly abundance but also the abundance and activity of 4 key predator species commonly found in cotton. For each predator we estimated a predator to prey (whitefly) ratios that can be used to decide when additional control actions are warranted. When the ratio is high control actions can be delayed; when the ratio is low it is likely that control actions are necessary. Ratios in between these levels requires careful consideration of the relative abundance of predators and whiteflies. A companion circular describes how to determine the abundance of both whiteflies and predators and how to use ratios for decision-making. The approach should not only reduce the need for insecticide applications but also reduce the risk to growers from pest insect losses.