Submitted to: National Sweetpotato Collaborators Group Progress Report
Publication Type: Abstract Only
Publication Acceptance Date: February 2, 2002
Publication Date: April 21, 2002
Citation: Jackson, D.M. and J.R. Bohac, 2002. Resistance of regional and standard sweetpotato entries to soil insects, Charleston, S.C., 2001. Pages 35-36 In W.D. McLaurin (ed.), National Sweetpotato Collaborators Group Progress Report, 2001. Interpretive Summary: Damage by soil insect pests was evaluated on six standard sweetpotato cultivars and 13 regional entries in the National Sweetpotato Collaborator’s Group Test at the U.S. Vegetable Laboratory, Charleston, S.C. in 2001. Sweetpotato entries were evaluated for damage by several insect pests. All regional entries had significantly lower damage ratings to the WDS complex (Wireworm, Diabrotica, Systena), flea beetles and white grubs than did the susceptible control sweetpotatoes, Beauregard and SC1149 19.
Technical Abstract: Damage by soil insect pests was evaluated on six standard sweetpotato cultivars (Hernandez, Beauregard, Regal, Ruddy, Porto Rico, and SCll49-19) and 13 regional entries L94-96, MS-152, MS-K39, NC-97A-04, W-311, W-328, W-334, W-346, W-352, W-359, W-365, W-366, and W-370) in the National Sweetpotato Collaborator's Group Test at the U.S. Vegetable Laboratory, Charleston, S.C. in 2001. Four replications of each entry were grown in single-row, 10-plant plots. Plots were evaluated for the WDS complex (Wireworm, Diabrotica, Systena), sweetpotato flea beetle (Chaetocnema confinis Crotch), and white grub larvae (Plectris aliena Chapin and/or Phyllophaga spp.). Analyses of variance indicated that there were highly significant entry effects for WDS index, percent clean roots, flea beetle ratings, and grub ratings (Table 1). There were no significant replication effects in any of the analyses of variance. All regional entries had significantly lower WDS ratings than SC1149-19 (Table 1). The highest levels of resistance to WDS (based on severity index) were for Regal, Ruddy, W-311, W-328, W-334, W-359, W-365, W-366, and W-370. These entries were also significantly more resistant than the standard cultivars Beauregard and Hernandez. All regional entries had significantly lower infestation levels of flea beetles than SC1149-19, however, none of the regional entries were significantly more resistant to flea beetles than the other standard entries Beauregard, Hernandez, or Porto Rico. All regional entries, except MS-K39, had significantly lower infestations of white grub larvae than SC1149-19. L94-96, Regal, Ruddy, W-311, W-328, W-334, and W366 were also significantly more resistnat to grubs than Beauregard in this test.