ALT Expression of Heterodera glycines Cysteine Protease 1 (CPR1) in soybean roots enhances nematode susceptibility. Transgenic roots in a susceptible Williams 82 background of individual composite plants growing in a sand/soil mixture were inoculated with 2,000 eggs per plant of the soybean cyst nematode (SCN) population TN10, and plants were grown for an additional 4 weeks. Cysts were collected and quantified as described in Materials and Methods. A, Representative images of cysts harvested and counted from CPR1-expressing roots using Nemacounter, which was designed in house at Iowa State University. Images show a mixed population of root debris and cysts (left) and the Nemacounter program detecting and counting the cysts specifically (right).