Effects of different growth regulators, gelling agents and carbon sources on in vitro growth of Berberis vulgaris var. asperma

Berberis vulgaris var. asperma, is a medicinal plant of Iran and lack of healthy vigorous seedlings is the main limitation of barberry cultivation. This research was carried out to develop a suitable technique for mass micropropagation of the species. Effects of different plant growth regulators, different gelling agents and different carbon sources on in vitro growth of barberry were studied in several experiments. Based on the results of the experiments, nodal segments containing 1-2 axillary buds of semi-hardwood shoots were the best explants for establishment of clean in vitro cultures. Surface disinfection of plant materials originated from adult trees was performed with immersion in 2 gl -1 of Benomyl solution for one hour, then 1% solution of commercial bleach for 15 minutes and rinsed three times with sterile distilled water. Explants cultured on media solidified with Phytagel were significantly better than the media with DifcoBacto agar and Agargel for shoot production. Addition of 3 gl -1 activated charcoal resulted in control of nutrient medium and explants browning, improvement of survival and in vitro growth of the explants. DKW medium containing 2 mgl 3 gl -1 activated charcoal and solidified with 2.5 gl -1 -1 BA, 0.5 mgl -1 IBA , 2 mgl Phytagel was optimum for in vitro growth of barberry and recommended for shoot multiplication of the species. Rooting experiment was carried out using a two phase procedure, root induction in media with high concentration of IBA, followed by transferring to growth regulators free medium for root development. No rooting was observed and further research is needed.