Estimating Absolute Density from Relative Sampling ofLygus lineolaris(Heteroptera: Miridae) and Selected Predators in Early to Mid-season Cotton
作者:
S. J. Fleischer,
M. J. Gaylor,
J. V. Edelson,
期刊:
Environmental Entomology
(OUP Available online 1985)
卷期:
Volume 14,
issue 6
页码: 709-717
ISSN:0046-225X
年代: 1985
DOI:10.1093/ee/14.6.709
出版商: Oxford University Press
数据来源: OUP
摘要:
Functional relationships ofLygus lineolaris(Palisot de Beauvois) and selected predator densities estimated with sweep net, drop cloth, whole-plant-bag samples (WPBS), and visual search were determined in early to mid-season cotton. Slopes of relative as a function of absolute densities were not different between years for most taxa. When compared against absolute density estimates (WPBS or visual search) drop-cloth estimates were generally more precise and captured a larger percentage of arthropods than 10-sweep samples of the sweep net. With few exceptions (notablyGeocorisspp. nymphs) the proportion of the absolute density estimated by drop-cloth or sweep-net samples was low (ca. 10–30%). Reasonably precise relationships (R2>0.50) of relative over absolute density were obtained for nymphs ofGeocorisspp.,L. lineolaris, andOriusspp.;Oriusspp. adults; and spiders. Relationships using total predator counts generally had greater precision than those using individual species and stages. Adults ofGeocorisspp., Coccinellidae, and possiblyL. lineolaris, however, were not estimated with precision by drop-cloth or sweep-net samples.
点击下载:
PDF
(748KB)
返 回