Sampling statistics were determined for adults of the froghopper Eoscarta carlIifex (F.) and associated symptoms on sugarcane crops in northern Queensland, Australia. Samples using 10 consecutive stems per sampling unit minimized the variance: mean ratios for all sample sizes used to sample adults. The Taylor power law described the relationship between mean and variance of samples based on 10-stem sampling units better than did the lwao regression model or the negative binomial model. All 3 models indicated that adults we're aggregated in distribution. Relationships to determine sample sizes for fixed levels of prf'c1sion and fixed-precision-Ievel stop lines for sequential sampling of adults were developed. There was a functional relationship between the variance and mean of untransformed froghopper counts, but this was eliminated by the Healy and Taylor transformation. Samples using 5 consecutive stems per sampling unit minimized the variance: mean ratios for all sample sizes used to sample symptoms. The Iwao patchiness regression was the only appropriate model for symptom data, and the slope indicated that damage is distributed uniformly between samples. Relationships to determine fixed-precision-Ievel stop lines for sampling of symptom data were developed.
Document Type: Research Article
Publication date: October 1, 1995
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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.