Regeneration frequency, shoot formation, phenotypic variation, selection for salt-stress tolerance and gene expression were studied in sorghum under the influence of long term culture. Shoot apices multiplication was obtained on MS medium supplemented with 0.5 mg/l 2,4-D and 4 mg/l BA. Use of relatively high cytokinin concentration and its accumulation with time as well as presence of 2,4-D may explain the ability of the cultured apices for multiplication through the formation of adventitious organs without shoot formation resulting in enhancement of somaclonal variation. Under the influence of long term culture, an aspect of somaclonal variation was a serious abolishment of shoot formation from in vitro multiplied buds. All bud clumps failed to form shoots still had the ability for multiplication via formation of adventitious bus and somatic embryos. Induction of somatic embryos increased with the increase of the number of subculture. Further aspects of somaclonal variation under the influence of long term culture were production of white and NaCl tolerant variants. In addition, protein profiles especially denatured PAGE showed an aggressive effect of long term culture on gene expression. The results indicated that somaclonal variation could be avoided if short term culture was followed up to six subcultures.