‘Covington’ originated from botanical seed harvested from the sweetpotato clone NC1528 (female parent). NC1528, an NCSU breeding line derived from ‘Regal’ (Jones et al., 1985), was one of 26 genotypes present in the sweetpotato breeding and genetics program 1997 open-pollinated polycross Streptomyces soil rot (SSR) breeding nursery. The SSR breeding nursery was planted at the North Carolina Department of Agriculture and Consumer Service's (NCDA&CS) Central Crops Research Station in Clayton, Johnston County, NC. The 26 genotypes present in the SSR breeding nursery were randomly mated; therefore, the male parent of ‘Covington’ is unknown. Seedlings from the SSR breeding nursery were planted in the NCSU Horticultural Sciences greenhouses in Mar. 1998. A single cutting was taken from each seedling and planted in the field in May 1998 in an “on-farm” trial and selected as a “single-hill selection” on 9 Sept. 1998. A “single-hill selection” includes the storage roots derived from the single plant cutting, typically ranging from two to 15 storage roots with two to 10 storage roots from selected hills being saved for asexual plant propagation the next year. The trial was conducted in Green County near Kinston, NC. ‘Covington’ was vegetatively increased, evaluated, and advanced as the clone NC98-608 with “98” referring to the year in which ‘Covington’ was selected as a “single-hill” and “608” indicating that ‘Covington’ was the 608th “single-hill selection” made by the breeding program in 1998. ‘Covington’ was first recognized as being a potentially competitive commercial cultivar after two further cycles of simultaneous increase and evaluation at the NCDA&CS Horticultural Crops Research Station, Clinton, NC, and the NCSU Cunningham Research Station, Kinston, NC, during 1999 and 2000.
Edmunds, B.A. & Holmes, G.J. 2008 Susceptibility of sweetpotato tablestock and high dry matter cultigens to Rhizopus soft rot Plant Dis. Mgt. Rpt. Report no. 2:V146
Jones, A., Dukes, P.D., Schalk, J.M., Hamilton, M.G., Mullen, M.A., Baumgardner, R.A., Paterson, D.R. & Boswell, T.E. 1985 ‘Regal’ sweet potato HortScience 20 781 782
Rolston, L.H., Clark, C.A., Cannon, J.M., Randle, W.M., Riley, E.G., Wilson, P.W. & Robbins, M.L. 1987 ‘Beauregard’ sweet potato HortScience 22 1338 1339
Schalk, J.M., Jones, A., Dukes, P.D. & Peterson, J.K. 1991 Approaches to the control of multiple insect problems in sweet potato in the southeastern United States 283 301 Jansson R.K. & Raman K.V. Sweet potato pest management, a global perspective Westview Press Inc Boulder, CO