Qualitative Determination, Quantitative Evaluation and Comparative Insecticidal Potential of Ruta Graveolens Essential Oil and Its Major Constituents in the Management of Two Stored Pests Sitophilus Zeamais (Coleoptera: Curculionidae) And Corcyra Cephalon

Abstract

Eco-chemical control based on essential oil mediated plant-insect interactions is an alternative method to the unsystematic use of insecticides, due to advanced structural diversity and allelopathic potential of essential oils. In this sense, present work was aimed at qualitative and quantitative investigation of chemical composition and the evaluation of insecticidal activities of Ruta graveolens essential oil and its major constituents against Sitophilus zeamais and Corcyra cephalonica in stored maize. Fresh leaves were subjected to hydrodistillaton and the chemical composition of oil was studied. Essential oil and its major constituents were then assessed for their allelopathic activity on test insects. Fifty components were identified, where long chain aliphatic 2-methyl ketones predominated the oil as major constituents. Results revealed strong concentration-, insect species- and time-dependent toxicities, in which oil caused 100 % mortalities at concentrations of 1.52 and 0.46 µL/cm2 against S. zeamais and C. cephalonica respectively after 24 hours of exposure. In aliphatic 2-methyl ketone series, respective congeners having odd and even number of carbon atoms were more effective on S. zeamais and C. cephalonica. These findings provide a scientific basis for the eco-potential of using essential oil of R. graveolens and its major constituents in integrated insect pest management programs.

Cytotoxic Plant Extracts towards Insect Cells: Bioactivity and Nanoencapsulation Studies for Application as Biopesticides

“…Given the high number of samples under study (22), we were interested in knowing which samples were the most toxic towards the Sf9 cell line. To this end, all extracts were evaluated at the same concentration (100 µg/mL) for their impact in the viability of these cells after 24 h of incubation.…”

“…zeamais in storage pest management programs [ 20 ]. Lee et al isolated essential oils from the flowers and leaves of R. graveolens , which were evaluated using fumigant and contact toxicity bioassays against store food pests, supporting the eco-potential of using R. graveolens essential oil and its major constituents in the management of stored pests [ 21 , 22 ].…”