Abstract:
Identification of diversity among germplasm collections is a prerequisite to select parents with
favourable traits for plant breeding programmes. Sweet potato (Ipomoea batatas (L.) Lam.)
genotypes frequently exhibits extensive variations in terms of its morphological characteristics.
A field experiment was carried out at National Root Crops Research Institute, Umudike, Abia
State, Nigeria during 2015 and 2016, to characterize morphological diversity among population
of 38 first filial generation (F1) sweetpotato genotypes derived from seeds generated through
controlled cross systems from International Potato Center, Kumasi, Ghana, comprised of three
different sweetpotato families (Ligri x Faara, Ligri x Apomoden and Ligri x Sauti), including
two local checks (UMUSPO3 and TIS87/8700). Morphological traits for the sweet potato
genotypes were scored using a descriptor manual at 90 days after planting for the shoot
morphology and at 120 days after planting for root morphology. Twenty characters were
introduced into SPSS software (Version 22) for cluster analysis which done on all the 20
characters, based on Euclidean distance and similarity matrix and a dendrogram generated using
the ward’s method. Most of the genotypes had pink skin colour and creamy flesh colour. Cluster
analysis revealed that all the genotypes were grouped into four different classes based on their
morphological traits. The results of this study revealed a suitable breeding strategy for superior
F1 genotypes for yield. This would provide a large gene pool for effective recombination to raise
promising sweet potato variety of considerable agricultural importance. |
