Repellency of Palizin® (Coconut Soap) with three laboratory techniques against five stored-product insect pests

Abstract

The heavy economic damages are the major concern in storage that was caused by coleopteran pests. The conventional control that is accomplished by synthetic pesticides created toxicity to non-target organisms, development of resistance and residue’s problems. Nowadays, with changes in legislation and consumer demand, alternatives to synthetic pesticide to manage the store product pest are increasingly needed. The repellent compounds could be considered as one of the mentioned methods in storage. In this study, five widespread species of stored product pest including Sitophilus oryzae Linnaeus, Tribolium castaneum Herbst, Rhizopertha dominica Fabricius, Oryzaephilus surinamensis Linnaeus and Lasioderma serricorne Fabricius were conducted to assay the percentage repellency (PR) of Palizin® (Coconut Soap 65%). Percentage repellency was achieved with beetles which were exposed to 0, 0.5, 1, 5 and 10% concentration using three techniques: filter papers, Y-shape tube and cup bioassays. In each of these methods, the means of PR reacted to increasing concentration except T. castaneum and O. surinamensis after 72 and 48 h. The maximum PR of Palizin® belonged to a concentration of 10% (except R. dominica at 5% and 48 h). Among the methods, except filter paper, degradation process resulted to a decreasing trend of PR. In the present experiment, Palizin® can be recommended as a limiting factor of all beetles and the data which were exported by Cub bioassay were closely adapted to reality condition of storage.