Effect of "external" superoxide anion on apoptosis in coleoptiles of wheat seedlings.

A derivative of phthalic acid, dibutylphthalate (DBP), which has gametocidal effect at the concentration of approximately 10(-4) M, increased apoptosis in coleoptiles of wheat seedlings. This was associated with activation of chromatin margination and generation of mitochondria-containing vesicles. At the same concentration, DBP activated the release by the coleoptiles of superoxide anion into the environment. Lower (10(-5) M) and higher (10(-3) M) concentrations of DBP virtually had no effect on either process. A probable mechanism of effect of the "external" superoxide anion on apoptosis within the plant cell is discussed.