Environmental assessment of MON 87411 maize expressing DvSnf7 RNA targeting western corn rootworm (Diabrotica virgifera virgifera) on beneficial soil arthropods and microorganisms

Nontarget soil dwelling organisms provide key functional ecological processes that contribute to biological control, soil quality, nutrient availability and fertility, and are important bioindicators in environmental assessments of agronomic crops genetically engineered with pest protectant traits.  As part of the ecological risk assessment for a maize product expressing a dsRNA targeting the Snf7 ortholog (DvSnf7) in western corn rootworm (WCR; Diabrotica virgifera virgifera), we conducted Tier 1 hazard tests on soil-dwelling arthropods and microorganisms. Where applicable, standardized test approaches were used and multiple ecologically relevant endpoints were considered to evaluate the potential adverse effects of DvSnf7 RNA on edaphic nontarget organisms. The nontarget organisms tested using worse case exposure scenarios include: Poecilus chalcites (Carabidae), Folsomia candida (Collembola), Eisenia andrei (Lumbricidae), and soil microorganisms. The results for the survival, growth and development of the soil macro-organisms including reproduction of F. candida, in addition to the carbon and nitrogen transformation by soil microorganisms, indicate no adverse effects to these taxa from exposure to DvSnf7 RNA at concentration  levels that greatly exceed ecologically relevant field exposures.