Larvicidal Activity of Silver Nanoparticles Synthesized from Azadirachta indica Leaf Extract Against Oryctes rhinoceros (L.) Beetle.

The coconut rhinoceros beetle, Oryctes rhinoceros (L), has been one of the major pests of coconut in India and other coconut producing countries causing direct or indirect losses to the crop. It can be controlled by eliminating the places where they breed and by manually destroying adult and immature (larvae). Botanical insecticides are relatively safer, degradable and are readily available source of biopesticides. Biosynthesis of pesticides from plant extracts is most promising approach for pest control. The present investigation aims to find out the possibility of eco-friendly management of the pest Oryctes rhinoceros by incorporating with silver nanoparticle synthesized from neem plant extracts. The silver nanoparticles (AgNPs) were synthesized by using aqueous extracts of Azadirachta indica. Formation of silver nanoparticles was observed by colour change of the solution, UV, FT-IR and SEM analysis. The Larvae is treated against different concentrations of plant extract and silver nanoparticles solution. 100% larval mortality was observed in higher concentration of silver nanoparticle solution. This result concluded that both silver Nanoparticles and leaf extract have larvicidal properties but Silver nanoparticles are more efficient and it serves as an alternative to synthetic insecticides for controlling harmful pest larvae. Hence the synthesized silver nanoparticles from the A.indica can be used as potential biolarvicidal agent against Oryctes rhinoceros.