Effects of Tansy Essential Oil from Tanacetum vulgare on Biology of Oblique-Banded Leafroller, Choristoneura rosaceana

The formulations TSW (tansy essential oil, surfactant, distilled water) and TSWD (tansy essential oil, surfactant, distilled water, dillapiol) increased the feeding rate of oblique-banded leafroller (OBLR) larvae with increasing concentrations of tansy essential oil. When tansy essential oil was continuously present at 0.1% and 1% in the diet, all OBLR larvae from susceptible and resistant populations died. The presence of 0.01% tansy essential oil in the diet affected female pupal weight, but not larval weight gain, larval developmental time and male pupal weight. Our results suggest that the concentration of tansy essential oil that significantly affects the developmental variables should be between 0.01% and 0.1% of tansy essential oil. Residues of the formulation TE (tansy essential oil, ethanol 95%) deterred oviposition of OBLR female.     

Insecticidal defenses of Piperaceae from the neotropics

Insecticidal and growth-reducing properties of extracts of 14 species of American neotropical Piperaceae were investigated by inclusion in diets of a polyphagous lepidopteran, the European corn borer,Ostrinia nubilalis. Nutritional indices suggested most extracts acted by postdigestive toxicity.Piper aduncum, P. tuberculatum, andP. decurrens were among the most active species and were subjected to bioassay-guided isolation of the active components. Dillapiol was isolated from the active fraction ofP. aduncum, piperlonguminine was isolated fromP. tuberculatum, and a novel neolignan fromP. decurrens. The results support other studies on Asian and AfricanPiper species, which suggest that lignans and isobutyl amides are the active defence compounds in this family.