Abstract:
Objective: To characterize 43 Kenyan yam cultivars using morphological characters.
Methodology and results: Yam cultivars were collected in the major yam growing districts in Kenya. Data of
17 morphological variables measured on these accessions were subjected to multivariate analysis using
Principal Component Analysis (PCA) and clustering criterion. The results indicated that the characters
contributing most to variability were twining direction, stem colour, spine shape, leaf type and presence or
absence of flowering for above ground plant parts; and tuber flesh colour, skin colour, shape of the tuber,
hardness of the tuber when cooked, and presence or absence of roots on the tuber surface for the parts
below ground. The pruned dendogram generated through agglomerative hierarchical clustering based on
the similarity matrix revealed four main groups of this species. One group had only one cultivar which was
collected in only one locality in Meru. This is possibly a newly discovered cultivar that has not been
previously documented.
Conclusion and potential application of findings: This study has showed that there is wide variability in the
major yam cultivars grown in Kenya and this can be used to breed higher yielding varieties or screen for
cultivars resistant to pests and diseases. The results would also be useful for conservation planning and
genetic improvement of the crop. Nevertheless further confirmatory research is required using molecular
tools to analyze the diversity detected
