EPG-Calc: a PHP-based script to calculate electrical penetration graph (EPG) parameters
Giordanengo P 2014, Arthropod-Plant Interactions, 8(2):163-169 journal link
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.
EPG systems is a private enterprise that has its roots in Wageningen University. It produces and distributes EPG equipment and consumables, offers free software to operate EPG equipment, to analyze EPG signals, and to process EPG data.
Aphid-AutoEPG software for analysing electrically monitored feeding behaviour of aphids
Prüfer T, Thieme T, Tjallingii FW, European Journal of Environmental Sciences 2014, 4(1):53-59 article link
Aphid-AutoEPG is a new software program, developed to acquire and automatically analyse electrical penetration graph (EPG) signals used for monitoring plant penetration by aphids. Characteristically EPG signals include waveforms that allow one to study the effects of plants on the acquisition and transmission of viruses, plant protection substances on pests and identify the location of resistance in plants to aphids. The success of electrical monitoring arises from the fact that different species of aphids generate similar EPG patterns. But the visual analysis of EPG waveforms in recorded signals is very time consuming, which has greatly hampered the wider application of EPG technology. To overcome this Aphid-AutoEPG software was developed, which has been extensively tested using data files for several different species of aphids, M. persicae, A. frangulae gossypii, M. albifrons, S. avenae, B. brassicae and N. ribis-nigri. The results have also been compared with visual analyses using Stylet+ software. When used in combination with the user friendly correction options Aphid-AutoEPG is not only easy to use but can also result in a considerable saving in terms of time.
Gluing the gold wire on the aphid dorsum from Yvan Pelletier (Agriculture AgriFood Canada) .wmv file
Electrical penetration graph from Wikipedia
A2EPG: A new software for the analysis of electrical penetration graphs to study plant probing behaviour of hemipteran insects
Adasme-Carreñoa F, Muñoz-Gutiérrez C, Salinas-Cornejo J, Ramírez CC, Computers and Electronics in Agriculture 2015, 113: 128–135 article link
This article introduces A2EPG, a new software application capable of automatically analyse signals derived from the electrical penetration graphs (EPG), a technique widely used to monitoring the plant probing behaviour of hemipterean insects. EPG records contain different well-known waveform patterns that are associated to specific behavioural activities inside the plant tissues, which are usually manually labelled in the present. A2EPG incorporates search engines for five EPG waveforms (Np, C, pd, G and E1) and provides output information indicating the time spans of each recognised waveform, which can be easily confirmed or manipulated by an expert user, reducing the overall time devoted to the analysis of EPG data. The application will be useful for researchers aimed to study the probing behaviour of piercing/sucking mouth parts, particularly aphids. The effectiveness of A2EPG was studied in EPG records obtained from individuals of two aphid species, exhibiting a substantial recognition efficacy for most of the considered waveforms. In general, A2EPG constitutes a useful tool for a rapid evaluation of EPG data over currently available software in the field.