Creation of variation through gamma irradiation and polyploidization in Vitex agnus - castus L.

•Dry seeds were treated with seven gamma radiation and six antimitotic agent doses.•The LD50 was found as 55 Gy for seed germination and 41.3 Gy for seedling survival.•16 variants, 8 of which derived from 10 Gy irradiation, possessed unique features.•0.05% colchicine resulted with chromosome doubling and created polyploid plant.•Mutation and/or polyploidization have potential to create variation in chaste tree.