High throughput nematode counting with automated image processing
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Nematode counting forms the basis for almost every assay in nematology: population surveys and culture density estimates all rely on accurate, rapid nematode counting. Accurate, rapid nematode counting is especially important for bioassays of entomopathogenic nematodes used for biological control. While manual microscope-based counting has traditionally been the standard, automated image processing holds promise for high-throughput nematode counting. Here we develop image capture and processing techniques to facilitate standard curve development and automated counting of two species of entomopathogenic nematodes. The techniques not only produce accurate nematode counts but also are rapid: timesavings over traditional manual counting are large and increase with increasing sample size. These techniques will likely be generally useful for quantification of all nematode species and potentially other small animals requiring quantification using microscopy.
KeywordsAutomated counting Entomopathogenic nematode Nematode quantification
We thank Karen Addison for maintaining nematode cultures. Wendy Meyer and Larry W. Duncan provided valuable comments on draft versions of the manuscript.
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