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Release Date: 02/22/2021

Fast Fonz Facts: Updates from Dr. Chris DiFonzo - Michigan State University

An updated version of the Handy Bt Trait Table is now posted on the Trait Table website (link below). The table is your one-stop shop to keep track of the many trait packages available in corn

This year, a new trait appears on the table.  The SmartStax Pro trait package, set for commercialization in 2022, has the same herbicide tolerances and Bt traits as SmartStax, but with one additional trait representing a unique mode of action: RNA Interference or RNAi. On page 1 of the updated table, I attempt to explain this mode of action. RNAi does not involve producing a toxin, as in Bt traits. Instead, RNAi interferes with or shuts down production of a particular protein. This process happens naturally in living things, but organisms can also be genetically modified for RNAi for a particular purpose. SmartStax Pro is a ‘first’ in several ways. It is the first use of RNAi technology for pest control and the first use where one species interferes with another. SmartStax Pro plants make a double-stranded RNA molecule that shuts down production of a specific key protein in the rootworm gut so that larvae slowly die as they feed on the roots. Both Bayer and Corteva have versions of SmartStax Pro coming soon, but you may see hybrids in field demonstrations this season.

You may also be interested in this video, ‘When Good Bts Go Bad’, recorded by me and my colleague Pat Porter from Texas A&M. This 40-minute talk covers the evolution of caterpillar resistance to Bt crops in the US and the factors that contributed to that resistance. View it free at: