Plant Pathology and Microbiology
Journal or Book Title
Plant Health Progress
Growing soybean cultivars that are resistant to the soybean cyst nematode (SCN), Heterodera glycines, is an effective way to preserve soybean yield and limit increases in population densities of the nematode. The ability of SCN populations to reproduce on germplasm lines that are used in soybean breeding programs to develop SCN-resistant cultivars was measured and classified originally by the race test (Golden et al. 1970; Riggs and Schmitt 1988) and more recently by the HG type test (Niblack et al. 2002). The “HG” represents the first letters in the genus and species names of SCN, Heterodera glycines. Seven different soybean germplasm lines or cultivars that have been registered in a scientific journal currently are the indicator lines in the HG type test. The indicator lines are assigned index numbers 1 through 7, and the ability of an SCN population to reproduce on each of the HG type indicator lines is determined by calculating a female index. The female index is the average number of SCN females produced on the HG type indicator line relative to the number produced on a standard, susceptible soybean cultivar in a 30-daylong HG type test conducted in a greenhouse (Niblack et al. 2002).
The American Phytopathological Society
Beeman, Augustine Q.; Harbach, Chelsea J.; Marett, Christopher C.; and Tylka, Gregory L., "Soybean Cyst Nematode HG Type Test Results Differ Among Multiple Samples from the Same Field but the Management Implications Are the Same" (2016). Plant Pathology and Microbiology Publications. 202.