Brazilian farmers have noted increased resistance to first-generation Bt technology in corn is on the increase.
And most researchers believe the irregular use of refuges has a significant part to play.
"Varieties that are still used in the U.S. and Europe simply aren't effective here anymore. We can't run through these technologies so quickly," said Richardt Tegnher, commercial manager at Braganca Agronegocios, which plants 55,000 acres in northern Mato Grosso.
Ag tech firms recommend farmers plant up to 20% of their area with non-Bt corn as a strategy to slow the growth of caterpillar resistance in this tropical farming environment ...