EPG-Calc: a PHP-based script to calculate electrical penetration graph (EPG) parameters
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Electrical penetration graph (EPG) technique is a powerful tool to investigate the hidden feeding behavior of piercing–sucking insects allowing to link recorded EPG waveforms to stylet penetration and complex behaviors related to feeding activities occurring within plant tissue. Calculating the numerous EPG parameters necessary to unravel the complex insect–plant interactions is very time consuming, and few tools have been developed to automate it. EPG-Calc is a rich internet application intended to fill this gap, providing a fast and user-friendly web-based interface that uses analysis files from dedicated software (STYLET+) or database-compatible CSV text files containing waveform codes and cumulative time as input, and produces output files in database-compatible CSV text or Microsoft Excel® XLS format that are directly usable by different statistical analysis softwares. EPG-Calc greatly reduces the time needed for EPG parameters calculation and allows to calculate more than 100 different parameters based on standardized definitions and calculus methods in such a way that avoid confusion between all kinds of definitions and calculations by individual authors.
KeywordsHemiptera Aphid Feeding behavior Insect–plant interaction Automated software
We are grateful to Dr Sébastien Dugravot and Dr Julien Saguez for their help in testing the script. Many thanks to Dr Freddy Tjallingii for his invaluable help in calculation methods.
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