Seeds of angico vermelho (Piptadenia peregrina Benth) were submitted to water potential by using polyethylene glycol (M.W. 6000). Decrease in germination percentage was observed when PEG concentration was increased up to - 6 bars, with no germination for higher water potencial. Presence of ABA in solution, having PEG or not, increases germination percentage. ABA effects apparently occurred only at cell-wall level because no changes were observed in native or denatured protein standards.