Antifeedant effect of polygodial and drimenol derivatives against Spodoptera frugiperda and Epilachna paenulata and quantitative structure-activity analysis.

BACKGROUND: The antifeedant activity of 18 sesquiterpenoids of the drimane family (polygodial, drimenol and derivatives) was investigated. RESULTS: Polygodial, drimanic and nordrimanic derivatives were found to exert antifeedant effects against two insect species, Spodoptera frugiperda and Epilachna paenulata, which are pests of agronomic interest, indicating that they have potential as biopesticide agents. Among the 18 compounds tested, the epoxynordrimane compound (11) and isonordrimenone (4) showed the highest activity [50% effective concentration (EC50 ) = 23.28 and 25.63 nmol cm-2 , respectively, against S. frugiperda, and 50.50 and 59.00 nmol/cm2 , respectively, against E. paenulata]. CONCLUSION: The results suggest that drimanic compounds have potential as new agents against S. frugiperda and E. paenulata. A quantitative structure-activity relationship (QSAR) analysis of the whole series, supported by electronic studies, suggested that drimanic compounds have structural features necessary for increasing antifeedant activity, namely a C-9 carbonyl group and an epoxide at C-8 and C-9. © 2018 Society of Chemical Industry.

Screening for extracts with insect antifeedant properties in native plants from central Argentina / Evaluación de la actividad antialimentaria de insectos en extractos de plantas nativas del centro de Argentina

Ethanol extracts obtained from aerial parts of 64 native plants from Central Argentina were tested for their insect antifeedant activity against Epilachna paenulata (Coleoptera: Coccinellidae) by choice test. Extracts derived from Achyrocline satureioides (Asteraceae), Baccharis coridifolia (Asteraceae), Baccharis flabellata (Asteraceae), Ruprechtia apetala (Polygonaceae) and Vernonanthura nudiflora (Asteraceae), showed more than 97 percent inhibition of the feeding of E. paenulata at 100 micrograms/cm2. These active extracts were further evaluated for their effectiveness against Spodoptera frugiperda (Lepidoptera: Noctuidae). All these extracts except for that derived from A. satureioides, negatively influenced the feeding behavior of S. frugiperda at 100 microrams/cm2...

Se evaluaron los extractos etanólicos obtenidos de las partes aéreas de 64 plantas de la región Central de Argentina, como antialimentarios de insectos mediante ensayos de elección, contra Epilachna paenulata (Coleoptera: Coccinellidae). Los extractos derivados de Achyrocline satureioides (Asteraceae), Baccharis coridifolia (Asteraceae), Baccharis flabellata (Asteraceae), Ruprechtia apetala (Polygonaceae) y Vernonanthura nudiflora (Asteraceae) mostraron mas de 97 por ciento de inhibición de la alimentación de E. paenulata a 100 microgramos/cm2. Estos extractos fueron posteriormente evaluados en su efectividad contra Spodoptera frugiperda (Lepidoptera: Noctuidae). Todos ellos, con excepción del extracto de A. satureioides, afectaron negativamente el comportamiento alimentario de S. frugiperda a 100 microgramos/cm2...