Effects of Myrsine stolonifera extracts on growth and developmentof Plutella xylostella larvae

Objective  To study the effects of Myrsine stolonifera extracts on growth and development of Plutella xylostella larvae.

Method  The bioactivities of M. stolonifera root, stem and leaf methanol extracts, and ethanol fractions of methanol extracts through macroporous resin against P. xylostella were determined by disc leaf method. The effects of ethanol fractions of extracts through macroporous resin on P. xylostella growth and development were studied.

Result  The root, stem and leaf methanol extracts of M. stolonifera and ethanol fractions of extracts through macroporous resin displayed stomach toxicity against P. xylostella. The 50% ethanol fraction of leaf extracts had the strongest insecticidal activity with an adjusted mortality of 75.56% after 72 h. The 95% ethanol fractions of root and stem extracts and 50% ethanol fractions of leaf extracts showed strong antifeedant activities and growth inhibition effects against P. xylostella larvae, with the antifeedant rates and growth inhibition rates over 90%. The extracts affected pupation and eclosion of P. xylostella.

Conclusion  M. stolonifera extracts display strong insecticidal activities against P. xylostella larvae. The insecticidal ingredients and mechanisms should be further studied.