A RAPID AND SIMPLE FLOUR-DISK BIOASSAY FOR TESTING SUBSTANCES ACTIVE AGAINST STORED-PRODUCT INSECTS
- 1 October 1996
- journal article
- Published by Cambridge University Press (CUP) in The Canadian Entomologist
- Vol. 128 (5), 865-875
- https://doi.org/10.4039/ent128865-5
Abstract
A rapid and simple flour-disk bioassay was developed to assay biologically active substances on several species of stored-products insects. The speed, simplicity, and parsimony of the bioassay derive from a single-step mixing of the test substance in aqueous solution with flour. Aliquots (100 μL) of the stirred suspension are then pipetted onto a polystyrene Petri dish using an Eppendorf pipettor and allowed to dry at room temperature overnight to produce uniform flour disks containing the test substance. After equilibration at 30 ± 1°C and 70 ± 5% relative humidity for 24 h, the disks are individually weighed and transferred to Petri dishes with weighed stored-products insects. After 3 days, the remainder of the disk and the living insects are weighed again for calculations of food consumption, utilization, growth, and mortality. Based on the flour-disk bioassay, the neem-based insecticide, Margosan-O®, significantly reduced consumption, growth, feeding, and dietary utilization in Cryptolestes ferrugineus (Stephens), Sitophilus oryzae (L.), and Tribolium castaneum (Herbst) in a dose-dependent manner. Margosan-O® also caused mortality, but the species differed widely in sensitivity, C. ferrugineus being the most sensitive and T. castaneum the least. The mortality of C. ferrugineus and S. oryzae was a consequence of both toxic and antifeedant (starvation) effects, but mortality of T. castaneum was caused entirely by its toxic action. Using a whole-kernel bioassay, it was found that Margosan-O® caused a dramatic reduction in the F1 progeny of all three species.Keywords
This publication has 14 references indexed in Scilit:
- A new bioassay for testing plant extracts and pure compounds using red flour beetleTribolium castaneum HerbstJournal of Chemical Ecology, 1994
- Repellent, toxic, and food protectant effects of pithraj,Aphanamixis polystachya extracts against pulse beetle,Callosobruchus chinensis in storageJournal of Chemical Ecology, 1994
- Biological activity of extracts of Trichilia species and the limonoid hirtin against lepidopteran larvaeBiochemical Systematics and Ecology, 1994
- Deterrent and insecticidal effects of extracts of pithraj,Aphanamixis polystachya (Meliaceae), againstTribolium castaneum in storageJournal of Chemical Ecology, 1993
- Effects of azadirachtin on the dietary utilization and development of the variegated cutworm Peridroma sauciaJournal of Insect Physiology, 1991
- Quantifying Food Consumption and Growth in InsectsAnnals of the Entomological Society of America, 1989
- Consumption and Utilization of Three Maize Genotypes by the Southern Armyworm12Journal of Economic Entomology, 1982
- BIOLOGICAL ASPECTS OF ANTIFEEDANTSEntomologia Experimentalis et Applicata, 1982
- Methods for Studying Aggregation and Feeding Behavior of the Confused Flour Beetle, Tribolium confusum (Coleoptera: Tenebrionidae)1Annals of the Entomological Society of America, 1965
- A Method of Computing the Effectiveness of an InsecticideJournal of Economic Entomology, 1925