Effects of two juvenile hormone analogues on hemolymph and fat-body metabolites of the eastern spruce budworm, Choristoneura fumiferana (Clemens) (Lepidoptera; Tortricidae)

Sixth-instar larvae of Choristoneura fumiferana were treated with LD50 concn of the juvenile hormone analogues fenoxycarb and methoprene. Fenoxycarb caused an initial decrease, then an increase, in haemolymph concn. Fat-body glycogen was depleted initially, then relatively increased in concn towards the end of the 6-day experimental period. Methoprene caused an opposite effect on haemolymph carbohydrates, but a similar effect on fat-body glycogen. Both treatments decreased protein concn. Fenoxycarb initially decreased, and then increased, the concn of fat-body soluble protein and initially increased and then decreased fat-body lipids. Methoprene decreased lipid concn in the haemolymph after 96 h. Lipid concn in methoprene-treated insects was initially greater, then less, and finally greater than that in controls..