Effect of Z-Asp-CH2-DCB on the dimensions of the TEs produced in Zinnia cell suspension cultures. A. Effect of Z-Asp-CH2-DCB on TE area; B. Effect of Z-Asp-CH2-DCB on TE length. The dimensions were measured at consecutive time points of 24 and 48 h intervals until the completion of TE differentiation at 168 h after the treatments by using differential interference contrast microscopy (Nikon DIC/Fluorescence microscope) with Image J software (Wayne Rasband, National Institute of Health, USA). The cells were treated with 1 mg/L NAA and 1 mg/L BA (0) and combinations of the hormones with 1, 10 and 100 nM of the irreversible broad spectrum caspase inhibitor Z-Asp-CH2-DCB (1, 10 and 100). NIM -non-inductive media. Error bars indicate SEM (n-1).