Study On Insecticidal Activity Of Plant Secondary Metabolites Against Tomicus Piniperda L

This paper contains four parts. The first part explored the methods of testing repellent activity on adult Tomicus piniperda L. The filter paper, the Y-shaped glass tube, the self-designed equipment of sense smell, the repellent glass box and the cylindrical glassware were used in the experiment. The results indicated that Only the cylindrical glassware can be used to test repellent activity on adult Tomicus piniperda L. because the adults can select their host plant both correctly and rapidly in the cylindrical glassware.The second part studied the contacting toxicity and the repellent activity of the ethanol extracts from twenty plant species against adult Tomicus piniperda L . The ethanol extracts were acquired by Soxhlet extraction from Equisetum arvense L., Paederia scandens (Lour.) Merr., Acorus tatarinowii Schott, Aremisia apiacea Hande, Perlla frutescens (L) Britt., Mentha haplocalyx Briq., Hippochaete hiemale (L.) Boerner ) , Eucalyptus globulus Labill., Eucalyptus robusta Smith, Litrus reticulata Banco, Agastache rugosa (Fisch.et Mey) O. Kuntze, Pterocarya stenoptera L. D. C., Sapium sebiferum Roxb, Nerium indicum Mill, Platycladus orientalis (L.), Ginkgo biloba Linn, Broussonetia papyrifera(. L.)Vent, Aconitum hupehensis Lem., Paris polyphylla Smith and Zanthoxylum bungeanum Maxim. The results showed that the extracts from twenty plant species all had lower both contacting toxicity and repellent activity. Of twenty kinds of plant, the extracts from Paris polyphylla Smith and Nerium indicum Mill had higher contacting toxicity than the rest, but their revised motality is only 33.5% and 33.25% respectively; the extracts from Mentha haplocalyx Briq. had higher repellent activity than the others , but its repellent index is only 51.25% at the concentration of 0.1gDW/ml.The third part studied the repellent activity of eight kinds of plant essential oil to adult Tomicus piniperda L in lab. The eight kinds of plant essential oil was acquired by the water-vapour distillation from Aremisia apiacea Hande, Perlla frutescens (L) Britt., Mentha haplocalyx Briq, Eucalyptus globulus Labill, Cinnamomum camphora (L.), Litrus reticulata Banco, Agastache rugosa (Fisch.et Mey) O. Kuntze and Acorns tatarinowii Schott. The results showed that the oil from Mentha haplocalyx Briq. had the strongest repellencies at the concentrtion of 10%, 2.5% and 0.625% , which repellent index was 100%, 100% and 96.55% respectively; The repellency of the oil from Mentha haplocalyx Briq. also persisted strongly at the concentration of 2.5% 24h ,48h and 72h after treatment, which repellent index was 100%, 95.51 % and 84.13% respectively , but down to 56.54% 7d after treatment.The forth part is the control experiment that the mint oil controlled adult Tomicus piniperda L. in forest. The results showed that the mint oil had the strongest repellencies at the concentration of 2.5%, which repellent index was 83.3%. At the same time, The repellency can persist for 3 days at the concentration of 2.5%, which repellent index was 75%.