Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: Evaluation of Plant Introductions and Dry Fleshed Sweetpotato Genotypes for Resistance to Soil Insect Pests, 2004

Authors
item Jackson, David
item Bohac, Janice

Submitted to: Arthropod Management Tests
Publication Type: Research Notes
Publication Acceptance Date: January 26, 2006
Publication Date: November 15, 2006
Citation: Jackson, D.M., Bohac, J. 2006. Evaluation of Plant Introductions and Dry Fleshed Sweetpotato Genotypes for Resistance to Soil Insect Pests, 2004. Arthropod Management Tests, Volume 31, Report No. M5, Online Journal at http://www.entsoc.org/pubs/index.html.

Interpretive Summary: Most commercial dry fleshed sweetpotato cultivars have little resistance to soil insect pests, which can severely limit marketable yields. Thus, there is a need to develop new varieties that have increased levels of insect resistance. This report describes the field evaluation of advanced dry fleshed sweetpotato entries from the USDA ARS sweetpotato breeding program at the U. S. Vegetable Laboratory (USVL), Charleston, SC. Seventy sweetpotato clones, including three insect susceptible check cultivars, were evaluated for insect resistance in replicated field trials at Charleston, SC. Several of the advanced, dry fleshed germplasm lines were more resistant to soil insect pests than were the susceptible check varieties. The most promising of these advanced clones are being developed as breeding lines or new sweetpotato varieties.

Technical Abstract: This report describes two field evaluations of dry fleshed sweetpotato plant introductions (PIs) and genotypes from the USDA ARS sweetpotato breeding program at the U. S. Vegetable Laboratory (USVL), Charleston, SC. The first field experiment had two insect susceptible, moist orange fleshed check cultivars (‘Beauregard’ and ‘SC1149 19’), an insect resistant, moist fleshed check (‘Regal’), and 20 mostly dry fleshed advanced entries that were evaluated for insect resistance in replicated field trials at the USVL. The second experiment consisted of an insect susceptible, moist orange fleshed check cultivar (‘SC1149 19’), an insect susceptible, dry fleshed check (‘Picadito’), two insect resistant, dry fleshed checks (‘White Regal’ and ‘Sumor’), and 46 mostly dry fleshed entries. For the first experiment, there were highly significant entry effects for percent uninjured roots, WDS index (Wireworm, Diabrotica, Systena), percent sweetpotato weevil damaged (Cylas formicarius elegantulus) roots, and percent flea beetle damaged (Chaetocnema confinis Crotch) roots, but not for percent grub damaged (Plectris aliena Chapin and/or Phyllophaga spp.) roots. Sixteen sweetpotato genotypes had a significantly higher percentage of undamaged roots than ‘SC1149 19’, and eight genotypes had a significantly higher percentage of undamaged roots than ‘Beauregard’. Thirteen of the entries had a significantly lower WDS rating than either of the susceptible check cultivars (‘Beauregard’ and ‘SC1149 19’). Fourteen entries had a significantly lower percentage infestation by SPFB than did the susceptible check cultivars. All entries had a significantly lower percentage of infestation by SPW than did ‘SC1149 19’. For the second experiment, there were highly significant differences for entry effects for all parameters: WDS index, percent uninjured roots, percent SPFB infestations, percent white grub infestations, and percent SPW infestations. Sixteen sweetpotato genotypes had a significantly higher percentage of undamaged roots than ‘SC1149 19’, and 11 genotypes had a significantly higher percentage of undamaged roots than ‘Picadito’. Thirty three entries had a significantly lower WDS rating than ‘SC1149 19’ and four genotypes had a significantly lower WDS rating than ‘Picadito’. Only two entries had a significantly lower percentage infestation by SPFB than did the susceptible check cultivars. Forty genotypes had a significantly lower percentage infestation by white grubs than did ‘SC1149 19’, and eight genotypes had a significantly lower percentage infestation by white grubs than did ‘Picadito’. Forty four of 49 genotypes had a significantly lower percentage of infestation by SPW than did ‘SC1149 19’.

Last Modified: 9/22/2014
Footer Content Back to Top of Page