Sampling Adults of Eoscarta carnifex (Hemiptera: Cercopidae) and Their Associated Symptoms on Sugarcane
| Autor: | K. J. Chandler, P. G. Allsopp |
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| Rok vydání: | 1995 |
| Předmět: | |
| Zdroj: | Journal of Economic Entomology. 88:1301-1306 |
| ISSN: | 1938-291X 0022-0493 |
| DOI: | 10.1093/jee/88.5.1301 |
| Popis: | Sampling statistics were determined for adults of the froghopper Eoscarta carnifex (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 were aggregated in distribution. Relationships to determine sample sizes for fixed levels of precision and fixed-precision-level 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-level stop lines for sampling of symptom data were developed. |
| Databáze: | OpenAIRE |
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