ABSTRACT

One of the many qualities that Dr. Maven values about Blanche is her logical approach to problems. So, when Blanche suggests that advance planning might improve the quality of the bioassays that they have planned for the future, Paula Maven listens attentively. They have already started several types of bioassays, among them continuous monitoring of the responses of their laboratory population; comparisons among more field populations when they can be collected; tests with chemicals, microbials, and, perhaps, physical factors; and periodic comparisons of the laboratory population, with its source populations collected from the field. In the future, surveys to determine patterns of resistance might even be necessary. Blanche explains her position quite firmly: in her opinion, they were just plain lucky in their first tests with the Fairfax, Pixley, and Schaeferville

populations. In two of the experiments, she tested five doses, but only had enough time to test four doses with the population from Pixley. The overall sample size for the Schaeferville experiments was almost twice that of the other two bioassays, but the number of doses was the same. The number of insects in the treatment groups was simply not consistent. Blanche needs a guide for dose selection and sample size because without it she could waste time, effort, and valuable insects and still not achieve the results that seem deceptively simple to obtain.