Heavy security means high value for corn pests
As security expert Bruce Schneier says, “If something is protected by heavy security, it’s obviously worth stealing.” That’s the case with maize plants, which protect their roots with poison. The poison, however, isn’t spread evenly through the tissue; seedlings distribute most of the poison to their crown roots, which are the source of the growing stem and contain most of the nutrients. For most insects, the high dose of poison is enough to make them consider lower profile embryonic roots. The corn rootworm, however, have developed immunity to the poison, and have evolved a fascinating response:
The larva of this beetle eats the roots of maize, corn and other cereals and it’s a significant pest that can ravage entire crops. Its success stems from its ability to turn maize’s defense against it. Robert found that the rootworm, unlike other insects, ignore the embryonic roots and head straight for the crown ones.
When Robert gave rootworms a mutant plant that couldn’t produce [poison], it lost its interest in the crown roots. Rather than being deterred by the plant’s poisons, the rootworm actually uses them to track down the most nutritious meals.
This is a pretty amazing evolutionary adaptation.