Summary
In order to identify the major characters which account for variation among Dioscorea rotundata, 14 high yielding accessions were studied using Single Linkage Cluster Analysis (SLCA) and Principal Component Analysis (PCA). The accessions were planted under the same environmental conditions for 3 years. Altogether, 40 characters were selected and coded for analyses. Results of SLCA agreed with that of PCA ordination on axes I, II and III. Three Groups of accessions were revealed. The PCA showed that the main distinguishing characters between the yam accessions were Leaf size, tuber size, colour of tuber, number of flower spikes per node and length of spike. Some accessions failed to flower and they were easily differentiated. The discrimination between groups and description of differences between groups were more strongly marked from the PCA than in the SLCA.
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Onyilagha, J.C. Numerical analysis of variation among Nigerian Dioscorea rotundata accessions. Euphytica 35, 413–419 (1986). https://doi.org/10.1007/BF00021849
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DOI: https://doi.org/10.1007/BF00021849