Thursday, August 2, 2012
Grand Ballroom
A regeneration system was developed for oriental lily (Lilium orientalis) based on leaf and bulb scales. Adventitious shoots were regenerated from leaves and bulbs of in vitro cultures using a MS medium containing thidiazuron (TDZ) or 6-benzylaminopurine (BA), and naphthaleneacetic acid (NAA). The highest percent regeneration from leaf explants was 74.2% grown in a medium containing 10.8 µM TDZ and 0.54 µM NAA. The highest mean number (4.4) of shoots generated from bulb scale explants was obtained using a medium containing 0.54 µM TDZ and 0.54 µM NAA. Adventitious shoots from both leaf and bulb sources were successfully rooted at rates ranging from 79.2% to 100%. The rooted plantlets survived after acclimatization in the greenhouse. Eighteen ISSR markers were employed to determine the genetic stability of the regenerated shoots in comparison to their mother plant. Eleven primers in total produced 70 clear and reproducible bands. Genetic similarity indicators among the clonal derivatives and the mother plant ranged from 0.92 to 1.0. Using this marker approach we were able to successfully group 15 micro-propagated progenies and the mother plant in a single major cluster with a similarity level of 92%. The somaclonal variation rate across the plantlets was estimated at 4.2%, indicating that direct shoot formation from explant regeneration is a safe method for multiplication of ‘true-to-type’ plants.