In order to optimize callus induction in Pistacia atlantica Desf. subsp. kurdica Rech. f., the effect of different plant growth regulator (PGR) combinations were studied. Inflorescence axis explants were cultured on WPM medium supplemented with 1, 2 and 3 mg/L of TDZ or 1, 2 and 3 mg/L of BA, in combination with 1mg/l different auxins: 2, 4-D, NAA and IBA . Callus initiation was observed in a...