It’s a border crossing of the worst kind. US biotechnology has spread southward to Mexico, its effects showing up in the native corn of remote southern villages. The high-tech invasion may threaten the birthplace of corn, which is also a key center of biodiversity.

The controversy poses a new question for biotech crops: If the new genetics invades its own cradle, will it weaken the old genetics? Or will it, oddly, enhance it?

0