Proceedings Volume 2010 (format .pdf) - SimpBTH

containing pumpkin extracts (1 ml/l) and IBA (1 mg/l) was quite efficient to induceroot formation and high growth rates (Butiuc-Keul et al., 2002). Malarz et al. (1993)and Weremczuk-Jeżyna and Wysokińska (2000) obtained rooting of shoots in MSmedium without addition of growth regulators. The rooted plantlets were thentransferred to the greenhouse or to the field where they continued to grow up with asurvival capacity varying from 50 to 95% depending of the used rooting media(Zapartan and Deliu, 2001; Butiuc-Keul and Deliu, 2001).The objective of this study was to develop an efficient method for highfrequency root induction and root growth, followed by identification of ex vitroconditions.MATERIALS AND METHODSPlant material: The micropropagated shoots of A. montana (seeds from theCarpathian Mountains, Ukraine) were used as plant materials for in vitro rooting andex vitro acclimatization. For root initiation, newly developed in vitro shoots (1.5 - 2.0cm) were excised individually from proliferating cultures and transferred to rootingmedia.In vitro rooting of microshoots: Half-strength Murashige and Skoog (1962) (MS)medium containing vitamins, 2% sucrose and solidified with 0.6% agar was used.Indole-3-butyric acid (IBA), α-Naphthalene acetic acid (NAA) and Indole-3-aceticacid (IAA) were the different auxin sources. Several types of rooting media weretested, MS0 medium without auxin (control) and MS media supplemented with IBA,NAA or IAA. The effect of different concentrations of auxins (0.5; 1.0 and 2.0 mg/l)on rooting was studied (Table 1). The plants were cultured vertically in the glass tube(150 x 20 mm), containing 8 ml of rooting medium.Two shoots per culture tube wereinoculated and each treatment involved 40 plants.The treatments were repeated twotimes. Data as percentage of root formation, number of roots per plant and rootlength were recorded after four weeks of culture. The data were statistically analyzedusing Sigma Stat computer package (Sigma Stat 3.1, Systat Software, San Jose,California, USA).Ex vitro acclimatization of plants: After in vitro rooting, the plantlets with newlyformed roots were taken out carefully from the culture vessels and washed with tapwater to remove agar sticking to the roots. The plantlets were transferred to smallplastic pots (6 cm diameter) containing different peat mixtures under in vivoconditions for acclimatization. Three types of mixtures were used: Mix1 – peat : coco(2:1 v/v); Mix2 – peat : perlite (2:1 v/v) or Mix3 – peat : perlite: coco (2:1:1 v/v/v).To maintain high humidity, the pots were covered with transparent polyethylene.After two weeks, polythene covers were removed in order to acclimatize the plants toex vitro conditions. Twenty plants were used for each treatment. In our secondexperiment, the plants were classified according to shoot hight and root length beforeacclimatization as short (1.0-1.5 cm and 0.5-1.0 cm, respectively), medium (1.5–2.0259