The U.S. EPA recently approved the first-ever RNA interference (RNAi) trait for insect resistance. Monsanto and Corteva Agriscience (agriculture division of DowDuPont) co-developed the trait to reduce resistance of the western corn rootworm (WCR) to SmartStax corn. A 2017 academic collaboration between the companies and the University of Nebraska found that SmartStax PRO (the trait with RNAi) increases WCR control efficacy under high WCR densities compared to SmartStax. In the U.S., 90% of corn produces insecticidal proteins thanks to transgenic modification, but resistance is emerging. Rather than controling with insecticidal proteins, RNA interference silences the expression of specific genes using double-stranded RNA (dsRNA).