Abstract:
Macadamia germplasm in Kenya originated from six seeds of Macadamia tetraphylla introduced in to Kenya in 1946 from
Australia . A study was done to determine diversity among 39 accessions of Kenyan Macadamia germplasm using leaf, fruit and
flower morphological traits. Analysis of variance indicated significant differences in leaf length, petiole length, number of spines per
leaf, fruit length and width, cluster length, number of fruits per cluster, raceme length and number of flowers per raceme. UPGMA
cluster analysis and principle component analysis (PCA) revealed inter- and intra-specific variation among species. Three major
clusters were formed corresponding to the two cultivated species; Macadamia integrifolia and M. tetraphylla, and their natural
hybrids. Leaf traits were the most effective in distributing the accessions in to respective clusters. PC1 accounting for 56.2% of leaf
variability was effective in separating the two species on opposite sides. These results showed the relationships among the
accessions and can, therefore, guide in cross breeding decision-making. However, molecular characterisation is required to confirm
genetic identity and genetic distances.
