Second generation of soybean gall midge now emerging

July 12, 2019 4:06 PM
Blog Post

My lab has been collecting adult and larval soybean gall midge for a few weeks. We used emergence cages in several habitats to collect adults. This year, they were only collected from 2018 soybean fields in Iowa. Two of my trapping locations have identified second-generation adult captures this week.

Soybean gall midge on soybean.
If you see areas of soybean with rapid wilt/death, look for midge larvae by splitting open stems.

Female and male soybean gall midge.
Female (about 2 mm in length) and male soybean gall midge collected in southwest Iowa in 2019. 

In addition to traps, we have been monitoring for positive larval detections in soybean this summer. As of 12 July 2019, eleven counties are reported to be infested. Several counties are new reports for Iowa (Ida, Sac, Mills, and Montgomery). Infested plants have been concentrated at field edges, close to 2018 soybean fields. Plants with soybean gall midge rapidly wilt and turn brown; dead plants have already been confirmed from the first generation larvae.

Soybean gall midge activity in Iowa.
Positive soybean gall midge larval detections for Iowa, as of 12 July 2019.

If you see soybean gall midge injury in any other county, send a photo via Twitter (@erinwhodgson) or email (ewh@iastate.edu). Many thanks!

 

Author: 

Erin Hodgson Associate Professor

Dr. Erin Hodgson started working in the Department of Entomology at Iowa State University in 2009. She is an associate professor with extension and research responsibilities in corn and soybeans. She has a general background in integrated pest management (IPM) for field crops. Dr. Hodgson's curre...