Bioactivity of Podophyllotoxin and Deoxypodophyllotoxin against Mythimna separata

Bioactivity of Podophyllotoxin and Deoxypodophyllotoxin against armyworm (Mythimna separata W.) were tested by method of disc leaf append. The results showed that Podophyllotoxin and Deoxypodophyllotoxin both possessed strong antifeedant, AFC_(50) (concentration causing 50%antifeedant rate) of 24 hour, 48 hour and 72 hour after treatment against the fourth instar larvae were 1.4086, 12.4514, 0.8881 mg/mL and 0.4686, 1.1066, 0.2599 mg/mL, respectively; Moreover, Podophyllotoxin and Deoxypodophyllotoxin had high development inhibition against armyworm. The stage of larvae, pupae and adult were all delayed comparing with that of CK, the pupation rate, eclosion rate and oviposition quantity all reduced obviously.