Seed and biotech firm Pioneer Hi-Bred has picked up both Canadian and U.S. clearance for a new insect-protection trait package to be offered in corn hybrids, with lower requirements for refuge crops. The DuPont subsidiary recently announced approvals for its Optimum Intrasect package, which it said will combine Dow AgroSciences’ Herculex I and Monsanto’s YieldGard Corn Borer traits and allow growers to “significantly reduce” structured above-ground refuge in their cornfields.
The Canadian Food Inspection Agency (CFIA) in January and the U.S. Environmental Protection Agency (EPA) in late 2010 allowed a lower-structured refuge requirement of five per cent for Optimum Intrasect corn crops, down from 20.
Monsanto’s Genuity SmartStax “stacked” traits, which also include insect-resistant Bt proteins, have also previously been allowed just a five per cent refuge.
Most other Bt crops now available come with a required minimum non-Bt refuge of 20 per cent, which in corn crops must be seeded in blocks, strips or on a field’s headlands or perimeter.
A non-Bt refuge is meant to ensure the survival of target insects that haven’t bred resistance to the Bt protein. Keeping a small amount of non-Bt plant matter in a field is meant to help dilute or eliminate any resistance traits that may develop through exposure to Bt over several generations.
The company’s Optimum Intrasect hybrids are to be the base for its Optimum AcreMax insect protection products which, upon separate CFIA approval, would combine both the Optimum Intrasect seed and the minimum above-ground refuge requirements in a single seed bag.
While grain from the trait package has been approved in Canada, the U.S., Mexico and Korea, the full Optimum AcreMax single-bag package isn’t yet available for sale or use and its products won’t be available for sale or distribution until field testing is complete and federal regulators approve it.
Pioneer Hi-Bred, meanwhile, plans to hold “wide-scale” on-farm demonstrations of the new corn hybrids across North America during 2011.