ARS | Publication request: Response of Sweetpotato Genotypes to Southern Root-Knot Nematode

Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: February 5, 2007
Publication Date: June 1, 2008
Citation: Thies, J.A., Harrison Jr, H.F., Labonte, D. 2008. Response of Sweetpotato Genotypes to Southern Root-Knot Nematode. HortScience. 43:622.

Technical Abstract: Fourteen sweetpotato [Ipomoea batatas (L.) Lam.] genotypes were characterized for resistance to Meloidogyne incognita in greenhouse tests. The following sweetpotato genotypes were evaluated: Beauregard, Sulfur, LSU 01-29, LSU 02-32, LSU 01-29, LSU 02-32, LSU 99-35, LSU 02-21, Bienville, Regal, Excel, Nemagold, Liberty, Jewel, U.S. Plant Introduction (PI) 399163, and Sumor. Root gall severity was rated using a 1.0 to 5.0 scale, where 1 = no galls, 3 = 26 to 51% root system galled, and 5 = more than 80% root system galled. Ratings of 1 and 2 were classified as resistant and ratings of 3 to 5 were susceptible. Gall indices ranged from 1.0 for Sumor to 4.4 for Beauregard. Numbers of eggs per gram fresh root ranged from 65 for Sumor to 17,693 for Beauregard. Reproductive indices ranged from 0.01 for PI 399163 to 3.42 for Beauregard. Based on results of these tests, Sumor, Liberty, PI 399163, Nemagold, Excel, Regal, and Bienville were highly resistant. Jewel, LSU 02-32, and LSU 02-21 were intermediate in resistance. LSU 99-35 and LSU 01-29 were moderately resistant, and Beauregard and Sulfur were susceptible.