Mutation breeding is one of the best ways to induce genetic variability within a crop species in a short period of time. It is equally a potentially powerful tool for cluster bean as other crops for genetic enrichment. The gamma radiation induced 190 M4 mutant lines of cluster bean [Cyamopsis tetragonoloba (L.) Taub.] obtained from Centre for Biotechnological Research (CBR), Dept. of BCI, College of Horticulture, Bengaluru and which were used for the field experiment on spikelet sterility during kharif 2017 (June - November) at College of Horticulture, Mysore. The present investigation revealed the presence of the 12 sterile mutant lines viz., A5, A16, A23, B52, B60, B61, C93, C94, C102, D124, D136 and (L.) Taub.] | Spikelet sterility studies on induced mutant populations of cluster bean Cyamopsis tetragonoloba L. Taub.