Abstract

Tigernut (Cyperus esculentus L.) is a nutritious crop of the sedge family.  In Ghana available local accessions have not been collected and characterized for conservation and utilization purposes. The objective of this study was to collect, conserve and characterize twenty-four local accessions of tigernut in Ghana based on agro-morphological traits. The ANOVA revealed significant (p<0.05) differences among the accessions for all the traits studied except for hundred nut weight, indicating the presence of sufficient variability among the accessions.  The hierarchical cluster analysis put the accessions into six major groups confirming a wide range of diversity among the accessions. The biplot of the principal components analysis revealed the scattering of the accessions in all the quarters which further suggest a higher level of variability among the accessions studied. The PCA also revealed that the first five PC accounted for a total of 88.4% variability among the accessions. PC1 accounted for 45.6% of the total variation with an Eigenvalue of 6.84. The correlation analysis among the traits showed significant and positive correlation between number of nuts and good nuts (r=0.94) and detached nuts and attached nuts. However, there was significant negative correlation among nut width and detached nuts (r = - 0.88) and harvest index and biological yields (r = - 0.77). Based on the study, accessions TPY, CCB, BB, DY, ADL, KB, KAY, WY1 and BKB which recorded high values for number of nuts, good nuts, nut length, nut width and harvest index could be included in breeding programs for varietal development of tigernut in Ghana.

Key words: Tigernut, Cyperus esculentus, Ghana, morphological characterization, cluster analysis, germplasm, principal component analysis, correlation, variability.