Wheat Stem Maggot (Diptera: Chloropidae): An Emerging Pest of Cover Crop to Corn Transition Systems

Authors

Gabriela Inveninato Carmona, University of Nebraska-LincolnFollow
Jennifer M. Rees, University of Nebraska - LincolnFollow
Ronald C. Seymour, University of Nebraska - LincolnFollow
Robert J. Wright, University of NebraskaFollow
Anthony J. McMechan, University of Nebraska - LincolnFollow

Document Type

Article

Date of this Version

2019

Citation

Published in Plant Health Progress 20:3 (2019), pp 147–154.

doi:10.1094/PHP-01-19-0009-S

Comments

Copyright © 2019 The American Phytopathological Society. Used by permission.

Abstract

The wheat stem maggot (Meromyza americana Fitch) (WSM) is a minor pest of wheat, rye, and other grasses. In 2017, growers in Nebraska reported dead center whorls and excessive tillering in early-season cornfields that followed wheat or rye terminated after planting corn. A survey was conducted to evaluate the risk factors for this insect in cover crop to corn transition systems. In each field, management practices and the percentage of injured plants were recorded. Symptomatic corn plants were collected from each field and dissected to determine larval and plant characteristics. In a few cases, small patches of a field were planted to a cover crop to manage soil erosion, and injured plants were only found where the cover crop was present. From these observations, the hypothesis is that terminating a cover crop after planting corn allowed the WSM larva to move from the dying cover crop to corn to complete its development. Cornfields infested with WSM had a frequency of injured corn plants from 0 to 60% with yield losses estimated at 30 bushels/acre. This paper provides the first detailed documentation of WSM injury in corn and addresses important management practices that may have influenced this uncommon situation.