Screening For Bioactivities Of Plant Extracts Against Phyllotreta Striolata (Fabricius) And Pilot Study On The Action Mechanism Of The Activities

In this thesis, Non-choice antifeeding and contact toxic effect of crude extracts of 93 species of plants from GuangXi were evaluated by the laboratory bioassay against the adults of Phyllotreta striolata(Fabricius); The pesticidal component of the four highest bioactive crude extracts— branches and leaves of Annona squamosa, roots and stems of Zanthoxylum nitidum, branches and leaves and stems of Gelsemium elegans, branches and leaves of Heynea trijuga were primarily isolated by different polarity solvents. The pilot studies about pesticidal activities, jointed pesticidal effect and action mechanism of bioactive isolation were evaluated further. The aim of these was providing scientific basis for the exploitation of medical plants of GuangXi, the effectual control of Phyllotreta striolata(Fabricius) and for the exploitation of botanical pesticides.The results of bioactive screening showed that most of the crude extracts had some bioactivities in different degree. When tested concentration reached 10g/L, the ethanol extracts of branches and leaves of Heynea trijuga, branches and leaves of Annona squamosa and root of...