Success of any breeding program depends on the ability to determine germplasm diversity and
genetic relationships among breeding materials. Genetic diversity is an invaluable aid in crop
improvement. This study aims at identifying genetic diversity among a set of sixty-six extra-early
yellow maize hybrids and four checks under drought environment. The hybrids were assessed
using cluster and principal component (PC) analyses based on morphological and agronomical
data observed in a randomized incomplete block design experiment with two replications. The
principal component reveals that the first three components account for 65% variability. PC1 gave
maximum variability and PC1 and PC2 can be utilized for hybridization program. The principal
component biplot reveals the relationship among traits and the distance of each variable in
determining variability among hybrids. The cluster diagram reveals four distinct groups. Group I
consisted of 13 hybrids, group II 12 hybrids, group III 18 hybrids and group IV consisted of 17
hybrids and were high yielding hybrids. Both principal component and cluster analysis revealed
the genetic diversity among the hybrids and identified genotypes that can be selected for drought
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