The Effect of Explant Types and Plant Growth Regulators On Callus Induction of Geranium (Pelargonium graveolens L’Her) In Vitro

Abstract The purpose of this study was to determine the effect of explant types and plant growth regulators on callus induction of geranium ( Pelargonium graveolens L’Her). Callus induction was carried out by culturing leaf and petiole explants from ex vitro geraniums on MS + 0.5 mg/l 2.4-D + 0.1 and 0.3 mg/l Benzyladenine (BA) or Kinetin. Each culture was carried out in 5 replications, cultures were incubated in rooms 25°C and 600 lux. The parameters days for callus induction and percentage of callus formation were observed. Geranium callus formation was influenced by types of explants and plant growth regulators. Petiole explants was able to induce callus better than leaf explants. Days for callus induction at second week and percentage of callus formation of petiole explants were 58 and 58% compared to leaf explants were only 53 and 54%. Plant Growth Regulators BA combined with 2.4-D was able to induce callus better than kinetin. The best callus formation was produced from petiole explants cultured on MS + 0.5 mg/l 2.4-D + 0.3 mg/l BA by 84%.