Skip to main content
ARS Home » Pacific West Area » Parlier, California » San Joaquin Valley Agricultural Sciences Center » Crop Diseases, Pests and Genetics Research » Research » Publications at this Location » Publication #324328

Title: Capabilities of the new “Universal” AC-DC monitor for electropenetrography (EPG)

item DOWELL, ANDREW - Consultant
item Backus, Elaine
item Cervantes, Felix
item Redinbaugh, Margaret

Submitted to: International Congress of Entomology
Publication Type: Abstract Only
Publication Acceptance Date: 6/17/2016
Publication Date: 6/17/2016
Citation: Dowell, A., Backus, E.A., Cervantes, F.A., Redinbaugh, M.G. 2016. Capabilities of the new “Universal” AC-DC monitor for electropenetrography (EPG). International Congress of Entomology. Available:

Interpretive Summary:

Technical Abstract: Electropenetrography (EPG), invented over 50 years ago, is the most rigorous and important means of studying the feeding of piercing-sucking crop pests. The 1st-generation monitor (or AC monitor) used AC applied signal voltage and had fixed amplifier sensitivity (input resistor or Ri) of 106 Ohms. The 2nd-generation monitor (DC monitor) was introduced in 1978 and uses DC applied signal with fixed Ri of 109 Ohms. In 2009, a 3rd-generation (AC-DC) monitor was introduced, providing either AC or DC applied signal with six selectable Ri levels of 106 Ohms (outputting pure R component for aphids) to 1010 plus 1013 Ohms (the latter outputting pure emf for aphids). Herein, capabilities of the AC-DC monitor are summarized. These include: 1) modern, updated electronics removing artifactual signals; 2) selectable settings to adjust the monitor recording characteristics to match the insect; 3) backwards-compatibility to reproduce the waveforms of any past type of monitor (AC or DC) for any arthropod, thus 4) making waveforms comparable across monitors for the first time; and 5) ability to produce a waveform library, a collection of waveform appearances of the same behavior from different Ri levels, to determine R and emf components. Block diagrams of AC-DC monitor electronics are displayed and used to illustrate the above monitor capabilities. In addition, examples of waveform libraries for various hemipteran species are displayed. Widespread adoption of the AC-DC EPG monitor will aid in development of resistant crop plants, more effective insecticide applications, and other novel management tactics for large hemipterans such as stink bugs, chinch bugs, tarnished plant bugs, and other important pests.