Field Performance and Clonal Variability in Sweet Potatoes Propagated in Vitro

Abstract

Abstract Six methods of propagating sweet potato (Ipomoea batatas L.), including 3 in vitro propagation methods, nodal propagation, and propagation by slips and cuttings from bedded roots of ‘Jewel’, were evaluated for field performance of the resulting plants and for the degree of plant-to-plant variability. The 2-year experiment (1982 and 1983) included a carryover study with plants obtained from the bedded roots of the first year's study. Plants were evaluated individually for yield, skin and flesh color, mutation frequency, dry matter, and protein content. In both years, plants propagated by stem cuttings and by slips from bedded roots produced higher yields than those propagated by tissue culture methods. Plants propagated by regeneration from cultured leaf explants were consistently lower in yield than plants obtained by all other methods. In the 1983 study, plants from stem cuttings from field-bedded roots significantly out-yielded plants from all other treatments. Stem cuttings from roots bedded in pots in a growth chamber out-yielded all tissue culture propagation methods, even though the tissue-culture explants also were obtained from these same roots. The carryover study showed that all differences in yield due to propagation method were dissipated with a single cycle of the normal propagation method for sweet potato. When yield data were analyzed according to the mother root origin of the plant material, there were significant differences among plants originating from different roots. Differences in skin color mutation frequencies due to propagation method existed in the 1982 study; however, the 1983 study demonstrated that these differences were also due to the origin of the plant material.