Efficacy of silica nanoparticles on groundnut bruchid, Caryedon serratus (Olivier) (Coleoptera, Bruchidae)

Abstract

In Senegal, post-harvest losses caused by groundnut bruchid, Caryedon serratus, are detrimental to farmers and affect national economy. The objectivie of this study was to investigate the effectiveness of silica nanoparticles against C. serratus. Silica nanoparticles were synthesized by reverse microemulsion and different concentrations (0.17, 0.33, 0.67 and 1.7 mg kg-1) were tested on mortality and fecundity of C. serratus. Result showed that silica nanoparticles had high toxicity on C. serratus adults. Adults\u2019 mortality increased with concentrations and time of exposure to each concentration. Up to 100% mortality was observed with high concentrations (0.67 and 1.7 mg kg-1) after 6 and 7 days post exposure, respectively. Additionally, fecundity potential of C. serratus was significantly (P<0.05) reduced by silica nanoparticles. Results of this study clearly demonstrated that silica nanoparticles can be used as a valuable tool for the control of C. serratus in stored groundnut ( Arachis hypogaea L.) .Au S\ue9n\ue9gal, les pertes post-r\ue9colte caus\ue9es par la bruche de l\u2019arachide, Caryedon serratus , sont pr\ue9judiciables aux agriculteurs et affectent l\u2019\ue9conomie nationale. L\u2019objectif de cette \ue9tude \ue9tait d\u2019\ue9tudier l\u2019efficacit\ue9 des nanoparticules de silice contre C. serratus. Des nanoparticules de silice ont \ue9t\ue9 synth\ue9tis\ue9es par micro\ue9mulsion inverse et diff\ue9rentes concentrations (0,17\ua0; 0,33\ua0; 0,67 et 1,7 mg kg-1) ont \ue9t\ue9 test\ue9es sur la mortalit\ue9 et la f\ue9condit\ue9 de C. serratus. Les r\ue9sultats ont montr\ue9 que les nanoparticules de silice pr\ue9sentaient une toxicit\ue9 \ue9lev\ue9e chez les adultes de C. serratus. La mortalit\ue9 des adultes augmentait avec les concentrations et le temps d\u2019exposition \ue0 chaque concentration. Une mortalit\ue9 allant jusqu\u2019 \ue0 100% a \ue9t\ue9 observ\ue9e avec les plus grandes concentrations (0,67 et 1,7 mg kg-1) respectivement apr\ue8s 6 et 7 jours d\u2019exposition. De plus, le potentiel de f\ue9condit\ue9 de C. serratus \ue9tait significativement (P <0,05) r\ue9duit par les nanoparticules de silice. Les r\ue9sultats de cette \ue9tude ont clairement d\ue9montr\ue9 que les nanoparticules de silice peuvent \ueatre utilis\ue9es comme un outil pr\ue9cieux pour lutter contre C. serratus dans les arachides stock\ue9es ( Arachis hypogaea L.)