|Mueller, John - CLEMSON UNIVERSITY|
Submitted to: Arthropod Management Tests
Publication Type: Research Notes
Publication Acceptance Date: September 4, 2002
Publication Date: September 4, 2002
Citation: JACKSON, D.M., BOHAC, J., MUELLER, J.D. EVALUATION OF ADVANCED SWEETPOTATO ENTRIES FOR RESISTANCE TO SOIL INSECT PESTS, 1999. ARTHROPOD MANAGEMENT TESTS. 2002. v.27. Report No. M-12. Interpretive Summary: Most commercial sweetpotato varieties 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 two field evaluations of advanced sweetpotato clones from the from the USDA-ARS/Clemson program at Charleston, SC, 1999. Forty-seven entries, including two insect-susceptible check cultivars, wer evaluated for insect resistance in replicated field trials at Charleston, SC. Some of the advanced lines were more resistant to soil insect pests than were the susceptible check varieties. The most promising of these advanced clones will be developed as breeding lines or new sweetpotato varieties.
Technical Abstract: Most commercial sweetpotato varieties have little resistance to soil insect pests. Thus, there is a need for new varieties that have insect resistance. This report describes two field evaluations of advanced sweetpotato entries from the USDA-ARS/Clemson program at the U. S. Vegetable Laboratory (USVL), Charleston, SC, 1999. For the first field experiment, two insect-susceptible cultivars, an intermediate check, an insect-resistant check, and 23 advanced entries clones were evaluated for insect resistance in replicated field trials at the USVL. There were highly significant entry effects for WDS index (Wireworm, Diabrotica, Systena), percent flea beetle-damaged (Chaetocnema confinis) roots, percent grub-damaged (Plectris aliena and Phyllophaga spp.) roots, and overall percentage of undamaged roots. Six advanced entries had a significantly higher percentage of uninjured roots than SC1149-19 or 'Beauregard'. Sixteen entries had significantly lower WDS ratings than SC1149-19 or 'Beauregard'. Eleven entries had a significantly lower level of infestation by flea beetles than did SC1149-19. Grub infestations were severe for this experiment, and none of the entries had significantly lower infestations than the checks. The second experiment had the same check clones plus 20 advanced sweetpotato entries. There were highly significant entry effects for WDS index, percent uninjured roots, and percent flea beetle infestations, but not for percent grub infestations. Ten advanced entries and 'Regal' had a significantly higher percentage of uninjured roots than did SC1149-19. Seventeen entries had significantly lower WDS ratings, and 22 entries significantly lower levels of infestation by flea beetles than did SC1149-19.