Although the cladoceran Daphnia magna Straus, or water flea, is sensitive to a broad group of insecticides, a satisfactory rearing method for bioassay is necessary for its practical use. A method has been developed using wide-mouth gallon jars for immature animals. They are then transferred to another chamber consisting of a large plastic funnel which has a plastic stopcock fused to the stem. To the lower outlet of the stopcock is fused a plastic bottle cap which holds an 8-oz bottle. A plastic ridge inside and near the bottom of the funnel holds a plastic ring covered with a fine screen, causing the adults to remain in the funnel, while the young pass through the screen and down into the bottle in response to light. Production consistently averaged 600 young daily for 18 months using 5 of these chambers. This method requires about one-third the time of previous methods. Many possible foods were studied. Best results were obtained with a mixture of algae (Scencdesmus obliquus) and yeast. Several artificial waters have been investigated, the best of which failed to maintain the culture satisfactorily after 32 generations. Search for a satisfactory defined water continues. Artesian water is used presently for maintenance of the culture as it is less variable than pond, lake, stream, or river waters.
Document Type: Research Article
Publication date: December 1, 1964
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.