Bracken and locust ecdysones: their effects on molting in the desert locust.

Bracken contains ecdysone derivatives that are active when injected into locusts. However, when fed to the desert locust as its sole or chief diet, it does not affect molting, growth, or development. There is evidence that, in locusts, the active ecdysones are dehydroxylated to (alpha)-ecdysone and passed out through the gut in the feces. There is no evidence for any uptake of ecdysones from the gut.