Illinois Fertilizer & Chemical Association
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Corn Rootworms Poised to Stage a Comeback as Bt Resistance Spreads

After several years of low corn rootworm populations, the "billion-dollar bug" is catching eyes again in the Corn Belt.
 
Populations of both western and northern corn rootworm are rebounding after a mild winter and favorable egg hatch conditions this year, and they're bringing some bad habits along: growing Bt resistance.
 
Corteva Agriscience recently confirmed their second report of western corn rootworm resistance to Cry34/35Ab1, the Herculex RW trait that is the underpinning of most pyramided rootworm hybrids, this summer. The trait is usually offered in pyramids that cross many brand platforms, with names such as SmartStax, QROME, Intrasect Xtreme, AcreMax Xtreme and Agrisure 3122.
 
With resistance already established against the other three rootworm Bt traits, growers in intensive corn-growing regions may need to be more innovative than ever when it comes to managing this pest, entomologists told DTN.
 
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