Plant civil defense

A novel enzyme in corn helps the plants defend themselves from voracious caterpillars by disrupting the insects' ability to digest food, and ultimately killing them, according to researchers. The enzyme could be used in tandem with other biological pesticides such as the Bt toxin to prevent the pests from developing resistance and making the toxin more effective.

"The enzyme is found in insect-resistant strains of corn, and it breaks down proteins and peptides in the insects' gut. It is a unique active defense against herbivory," says Dawn Luthe, professor of plant stress biology at Penn State.

Luthe and researchers at Mississippi State University have since developed several lines of corn resistant to multiple pests, using conventional plant breeding and insect-resistant strains of corn from Antigua.

All farmers use pesticides no matter what agronomic system they practice. There has been an evolution of pesticides from more toxic and persistent early compounds based on arsenic, lead and other harsh poisons to more benign and selective ones. That's the story that those reasoning in good faith about pesticides should be telling rather than a false story of a dichotomy between those who use pesticides and those who don't. The issue is only which pesticides are used and over time that becomes an increasingly irrelevant distinction since they are all becoming safe as well as effective.