Response to in vitro culture of Scilla siberica was found to be both explant and hormone specific. Bulb scale explant showed optimum response to callusing in MS medium with 2,4-D and kinetin supplement. Leaf explants did not show callusing and optimum result for direct regeneration of shoots was obtained on MS medium with BAP supplement. This explant specificity to in vitro response in S. siberica is evidently under genetic control and a measure of genetic diversity. Chromosome studies of regenerants also indicate the presence of marker heteromorphic chromosomes as reported in in vitro plants in this laboratory. The aged callus also retains cell viability but regeneration competence of the variants was not recorded in the medium used. © 2002 Elsevier Science B.V. All rights reserved.