Rearing the soil arthropod Folsomia candida (Collembola: Isotomidae) on agar plates and estimating biomass by protein staining with Ponceau S

Abstract

Folsomia candida Willem (Collembola: Isotomidae) is a common soil arthropod used in standardized toxicological testing. We describe a simple method for rearing Collembola on agar plates and evaluating toxicity in the absence of charcoal, which has potential detoxifying effects. We developed a quantitative method for determining biomass by reversible protein staining of hexane-treated Collembola with Ponceau S. Protein staining has advantages over photometric methods for enumerating Collembola, and agar substrate provides a simple medium for testing toxicity of water-soluble substances independent of soil composition. Using these protocols, the 50 % effective concentration (EC50) for the insecticide imidacloprid is ~0.2 µM, or 0.05 mg/kg agar substrate.