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New Multi-State Entomology Publications (05/10/18)

Management Of Insecticide-Resistant Soybean Aphids E1878 & Pulse Crop Insect Diagnostic Series Field Peas, Lentils And Chickpeas E1877

New Multi-State Entomology Publications


Soybean producers have a new tool to help them manage insecticide-resistant soybean aphids. This new extension publication summarizes the development of insecticide resistance in soybean aphids in the upper Midwest and how to manage insecticide resistance using an Integrated Pest Management approach. The series was a collaborative effort among Extension Entomologists from the University of Minnesota, Iowa State University, NDSU and South Dakota State University.

In 2017, failures of certain pyrethroid insecticides for management of some soybean aphid populations were observed in commercial fields (see red areas on map on page 2), and resistance to bifenthrin and lambda-cyhalothrin has been documented through small-plot research and laboratory bioassays.

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Key IPM strategies to slow the development of insecticide-resistant soybean aphid include:

  • Use the economic threshold (E.T.) of 250 aphids per plant with >80% of plants infested to decide when to treat fields (Or, use speed scouting).
  • Apply insecticide using the full labeled rate with proper spray technology (good coverage) and under favorable environmental conditions (winds <10 mph).
  • If more than one application is necessary for soybean aphids or other insect pests, rotate to a different mode of action (MOA).

In E1878, two foliar-applied insecticide tables are included that list the different MOAs for insecticides with a single active ingredient and for premix insecticides with two active ingredients.

The “Management of insecticide-resistant soybean aphids E1878” is available online at

This work is supported by the North Central Soybean Research Program and each state’s soybean society including the Minnesota Soybean Research & Promotion Council, Iowa Soybean Association, North Dakota Soybean Council and South Dakota Soybean Research & Promotion Council.




Pulse crop producers have a new tool to help them identify insect pests that attack chickpeas, field peas and lentils in the major pulse-growing areas of the U.S. The new “Pulse Crop Insect Diagnostic Series” from the North Dakota State University Extension summarizes insect pests of the northern Plains (Montana, North Dakota and South Dakota) and the Palouse area of the Pacific Northwest (Washington, Idaho and Oregon). E1877 was a collaborative effort among NDSU, University of Idaho, South Dakota State University and Montana State University.

The series features integrated pest management (IPM) tools for managing major insect pests of pulse crops. Sections of the series include pest identification, crop damage, monitoring or scouting tips, economic threshold, cultural control, host plant resistance, biological control and chemical control. The insect pests covered in the series are wireworms, cutworms, pea leaf weevils, grasshoppers, Lygus bugs, pea weevils and pea aphids.

Some of the beneficial organisms that attack these insect pests of pulse crops also are addressed. For example, Lady beetles (adults) and larvae that consume about 50 to 300 aphids per day are an example of beneficial organisms. Other effective predators covered are lacewings or aphid lions, minute private bugs, and Syrphid flies or hoverflies. The series also includes information about tiny parasitic wasps called parasitoids that lay eggs inside the body of aphids, and as larvae hatch from the eggs, they eat the aphid from the inside out, killing it.

The “Pulse Crop Insect Diagnostic Series” is available online at

This work is supported by the U.S. Department of Agriculture’s National Institute of Food and Agriculture, Crop Protection and Pest Management Program through the North Central IPM Center (2014-70006-22486).

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Janet J. Knodel

Extension Entomologist


This site is supported in part by the Crop Protection and Pest Management Program [grant no. 2017-70006-27144/accession 1013592] from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed are those of the website author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

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