A digital image analysis system for comparing groups of small nematodes

A digital imaging system was developed for measuring various physical characteristics of individual nematodes and for comparing groups of nematodes. The equipment consists of a microscope, a video camera, a video digitizer, interactive displays, and a computer. Various physical and mathematical methods were incorporated, algorithms devised, and computer software written for image acquisition, editing, and analysis. To test the system, four populations of an isolate of the pinewood nematode, Bursaphelenchus xylophilus, subjected to 100% relative humidity at 22 C for 0, 12, 24, or 48 hours were compared. The results showed that the system can be used to measure physical parameters of individual nematodes and to differentiate groups of nematodes.