Effects of Rhodojaponin-III on Nervous System of Larvae of Imported Cabbage Worm, Pieris rapae L

Effects of Rhodojaponin-III(Abbr.R-III) on nervous system of 5th instar larvae of imported cabbage worm, Pieris rapae L. under laboratory conditions were reported. Results showed that activities of acetylcholinesterase (AChE), both in vitro and in vivio were not significantly different from that of the control, while contents of acetylcholine (ACh) were remarkably decreased. R-III had reversible activated effects on Na+- K+ - ATPase and Ca 2+ -Mg2+ ATPase activities. R-III activated all ATPase activities when treated after 24h. A low dosage of 1 μg of R -IIIper larva significantly activated all ATPase activities over the control. It's observed that worms treated after 60h by 1～3μg R-IIIper larva recovered. While they were fed with 5～10μg R -III per larva, ATPase activities decreased to levels less than that of the control