Genetic Evaluation of Polycross Hybrids of Sweet Potatoes

Sweet potato is an important staple crop in Papua New Guinea (PNG). Evaluation of polycross hybrids of sweet potato to identify tuber bearing progenies was conducted at PNG University of Technology farm, LAE, between March and November 1991. Sweet potato seeds were obtained from a polycross nursery of nine sweet potato clones adapted to PNG. Nine hundred and eight seeds were scarified and sown. Out of 689 germinated and established seedlings, 77 mature plants (11%) were selected as having the potential to produce tuberous roots. These selected progenies were advanced into their first clonal generation for further yield evaluation. The highest yielding half-sib progeny was obtained from a hybrid parent UIB-52. Heritability values for tuber yield, tuber number and vine weight were 0.80, 0.62 and 0.10, respectively. Parental clones UIB-37, K-42 and Merlkan showed good general systems in improving sweet potato in the lowlands of PNG.