4-12 IAT Resistance

 The evolution of resistance. 

Farmers have waged battle with the western corn rootworm for years. Most often this war is fought at planting time. There were decades through which the weapon of choice was simple crop rotation. And then in the mid-1990’s - the western corn rootworm adapted. The corn planter remained the delivery method for control - but soil insecticides were applied along with the seeds sown.

It was the turn of the century when  Monsanto introduced YieldGard Bt corn - and the soil insecticides were set aside. And now - a decade later - the western corn rootworm has adapted once again - according to Entomologist Mike Gray:   “We know that the evolution of resistance to the Kry 3 BB-1  protein has occurred and was confirmed by Aaron Gasp, a professor at Iowa State University, going back to 2011. Aaron noted that where evolution of resistance occurred, there were several patterns that were fit. Number 1 among continuous corn in many cases for several years some non-rotation of crops as well as non-rotation of that particular trait.