Impact of Neem Extracts, Azadirachta indica A. Juss Induced against Red Palm Weevil, Rhynchophorus ferrugineus (Olivier) Attacking Date Palm Orchards in Egypt

Abstract

Red palm weevil (RPW), Rhynchophorusferrugineus (Olivier) (Coleoptera: Curculionidae) is considered to be themost devastating boring pest attacking the date palm trees, Phoenix dactyliferaL. (Arecales: Arecaceae). During this study the date palm orchards wereinvestigated at Ismailia governorate in Egypt to throughout 2015-2016 andresults revealed the wide distribution of RPW with high infestation rates atthe visited localities. Rates and degrees of infestation were detected throughthe attacked spots showing a direct proportional rate with the total planteddate palm trees in each location recording a highest infestation rate of 91.6%and a maximum infestation degree was 3.4 hole/ tree. Least average infestationlevels were 14.9% and 1.19 hole/ tree. Extracts of neem seeds, Azadirachta indica A. Juss(Sapindales: Meliaceae)were tested in the laboratory against the RPW stages using organic solvents inaddition to the commercial Nemazal brand as a comparison treatment. Laboratoryexperiments revealed a potential effect of the used titers againstboth adult and larval R. ferrugineus stagesresulting in high mortality rates reached 85.4 and 79.5%on average for larval and adult stages, respectively. Consequent field trialswith such agents were conducted on both remedial and protective scalesrevealing a considerable reduction of infestation was 60.8% and 53.1% repellencyon average for all applied treatments. Field trials proved the possibility ofthose treatments usage in the control programs of that borer in Egypt.