By Adam Varenhorst
Researchers recently determined that the soybean gall midge, discovered in South Dakota in 2015, is actually a previously undocumented species. The origin of the new species, Resseliella maxima Gagné, (Image 1.) is still unknown. Although we can no longer say we don’t know what species it is, we still have a lot of questions to answer. The most pressing questions are regarding the soybean gall midge life cycle and developing a better understanding of when it emerges and attacks soybean.
Image 1. Soybean gall midge adult.
The wet start to 2019 has prevented early plot planting from occurring to evaluate the impact of planting date on the soybean gall midge in South Dakota. However, we will still be evaluating a number of treatments against this pest. It is unlikely that the current conditions are having any impact on the soybean gall midge, and we will continue monitoring for adult emergence.
Based on the distribution of damage in 2018, fields in southeastern South Dakota should be monitored closely for soybean gall midge activity once soybean emerge.