Parasitoids in North American soybean fields: the effect of neonicotinoid seed treatments and hyperparasitism on soybean aphid biological control, by J.S. Dregni, M. Ferrer-Suay, K, Welch, J.M. Kaser, and G.E. Heimpel. Presented to the Entomological Society of America, 2018.
In brief:
Neonicotinoid seed treatments had no measurable effect on the biological control of soybean aphid by parasitoids.
Hyperparasitoids were found in soybean fields attacking Aphelinus certus at rates of 4 to 17 % of mummies emerging as hyperparasitoids.
We found one of the most abundant hyperparasitoids, Alloxysta brevis, is thelytokous, i.e., an unmated female adult can produce female offspring.
We were unable to recover evidence of biological control agents released in Minnesota from 2009 to 2017.