Submitted to: Journal of Nematology
Publication Type: Abstract Only
Publication Acceptance Date: June 2, 1997
Publication Date: N/A
Technical Abstract: A reliable, efficient method for extracting all root-knot nematode stages from potato tubers was developed. Tuber tissue was excised to a depth of 12 mm in 3 mm intervals from 10 tubers with varying levels of nematode infestation. Tissue was incubated in a pectinase plus cellulase solution on a shaker overnight at room temperature. Sugar flotation-centrifugation was used to separate nematodes from plant tissue. Nematodes in the supernatant were stained with acid fuchsin and counted by stage and sex. Nematodes remaining in the pellet were also counted. The supernatant contained 97% of the total nematodes, with 3% remaining in the pellet. The percentage recovered in the supernatant varied significantly with stage; 99.7% for J2, 97% for J3/4, 86% for females, and 93% for males. These percentages did not vary significantly with tuber or depth of tissue. Population estimates based on this technique are significantly higher than those based on counts of nematodes in stained tuber tissue.