Alleged Relationship of Fireflies, Rootworms, and Bt Corn in Indiana

Unusual flashing of fireflies have been observed and reported during the first weekend of May in Indiana. The emergence of fireflies is usually a life cycle indicator of the start of rootworm egg hatching. However, the observed flashing of fireflies extended for another three weeks is not normal.

Steve Mrockiewicz of Syngenta Crop Protection in WC Indiana also observed this strange sighting. Mrockiewicz' thesis in 1990 confirmed that the emergence of adult fireflies under genus Photuris happens at the same time as the hatching of western corn rootworm, a devastating corn pest. Researchers at Purdue University observed that rootworm development have changed patterns in recent years. One of the probable causes of this change in pattern is the widespread planting of Bt corn. The researchers aver that Bt corn may have slowed down the development of rootworms and increased the survival of fireflies, but they still need more years of study in order to confirm this assumption.

The original article is available at http://extension.entm.purdue.edu/pestcrop/2010/issue6/index.html#rootworm.