Development of End-User Preferred Sweetpotato Varieties

Sweetpotato (Ipomoea batatas (L.) Lam) is the fourth most important root and tuber crop in Ghana, in terms of production. Attainment of increased sweetpotato utilization has become an important breeding objective in Ghana recently. The major emphasis in breeding is on the development of farmer/consumer preferred varieties. This study aimed at developing farmer/consumer preferred sweetpotato cultivars for increased utilization in Ghana and beyond. One hundred and fifteen sweetpotato accessions were collected and evaluated at two ecozones in the major and minor cropping seasons in 2011 to identify low sugar parents for hybridization. Two released varieties (Histarch and Ogyefo) and eight breeding lines (AAT-03-025, CIP 442264, CRIWAC 25-10, CRIWAC 30-10, DOS 03-006, CRIWAC 11-10, CIP 440095 and CRIWAC 19-10) were selected and used as parents. Genetic variability was significant for all the traits studied. Sufficient useful genetic variation was present in the materials studied and was exploited to provide for substantial amount of improvement through selection of superior genotypes. Negative heterosis was observed for sugar content and this is very important for breeding because Ghanaians prefer non-sweet varieties. Fifteen percent of the F1 hybrids of Histarch and Ogyefo were non-sweet. These will meet the staple food needs of Ghanaians. Eight hybrids were identified as potential non-sweet varieties for further testing multilocation on-farm for release. These were Ogyefo × Histarch-11, Histarch × Ogyefo-13, Histarch × Ogyefo-52, Histarch × Ogyefo-37, Histarch × Ogyefo-65, Histarch × Ogyefo-88, Histarch × Ogyefo-39 and Histarch × Ogyefo-16.