Phenotypic diversity and trait association in cluster bean (Cyamopsis tetragonoloba)

Cluster bean (Cyamopsis tetragonoloba) is an important industrial crop in arid and semi-arid regions. The present investigation reports phenotypic variability in 219 guar accessions based on 16 morphological traits for two consecutive years. The ANOVA showed significant differences among accessions for all the traits. The high estimates of GCV, PCV, h2b and GA were observed for days to 50% flowering, plant height, number of pods/plant and fruit yield/plant. The seed yield/ plant (SYP) showed significantly positive correlation with the number of pods/cluster, the number of pods/ plant, fruit yield/ plant, and the number of seeds/ plant in both years. Principal component analysis showed that the first three principal components accounted for more than 75% of the total variation in both years. The hierarchical clustering by Ward’s minimum variance grouped all 219 accessions into nine clusters. The cluster analysis revealed that cluster VII was the largest one and contained the maximum accessions in both years. Most of the clusters contained common accessions and cluster IX had the maximum common accessions. The cluster mean revealed that the cluster VIII was characterized by taller plant height, less number of branches, large number of pods/ plant, large pod length and pod width and high fruit yield of the accessions. The present study determines some promising diverse accessions with high potentials that could be useful for further genetic improvement programme in cluster bean. © The Author(s) under exclusive licence to Society for Plant Research 2023.