Evaluation of perennial species for response to , and .

Root-knot ( (Kofoid & White) Chitwood), reniform ( Lindford & Oliveira), and lesion nematodes ( (Cobb) Filipjev & Schuurmans Stekhoven) are plant-parasitic nematodes that feed on soybean ( (L.) Merr.) roots, limiting seed production. The availability of resistance in soybeans to these nematodes is limited. However, new sources of resistance can be discovered in wild relatives of agronomic crops. Perennial species, wild relatives to soybean, are a source of valuable genetic resources with the potential to improve disease resistance in soybean. To determine if these perennials have resistance against nematodes, 18 accessions of 10 perennial species were evaluated for their response to and , and eight accessions of six perennial species were evaluated for their response to . Pot experiments were conducted for and in a growth chamber and in vitro experiments were conducted for . We found both shared and distinct interactions along the resistance-susceptible continuum in response to the three plant-parasitic nematode species. Ten and 15 accessions were classified as resistant to based on eggs per gram of root and gall index, respectively. Among them, plant introductions (PIs) 446983 and 339655 had a significantly lower gall index than the resistant soybean check cv. Forrest. Of three resistant accessions identified in this study, PI 441001 showed significantly greater resistance to than the resistant check cv. Forrest based on nematodes per gram of root. In contrast, no resistance to was recorded in any perennial species.