Inter-plant compensation for southwestern corn borer (Diatraea grandiosella) injury

An emerging insect resistance management concept in field corn (Zea mays L.) is a “refuge-in-a-bag” approach. This involves corn packaged as a 5 or 10% blend of non-Bt (refuge) seed with seed of a stacked Bt corn hybrid. Tests were done in 2010 and 2011 by infesting southwestern corn borer larvae (Diatraea grandiosella Dyar) on non-Bt plants that were interspersed within a stand of VT3Pro corn, simulating a refuge-in-a-bag system. Larvae were infested at three different growth stages of corn. Our objective was to determine how infestations affected yield of both the non-Bt and neighboring (Bt) plants.  The goal was to evaluate how Bt plants might compensate for injury to neighboring non-Bt plants in a refuge-in-a-bag system.