Optimization of an efficient micropropagation protocol and assessment of plant genetic fidelity by RAPD markers in pistachio (Pistacia vera L.)

Abstract

An efficient protocol for the micropropagation of pistachio (Pistacia vera L.) is reported. Various concentrations and combinations of 6-benzyladenine (BA), kinetin (KIN), gibberellic acid (GA<inf>3</inf>) and naphthalene acetic acid (NAA) were tested in order to optimize axillary bud development and multiple shoot formation from uni-nodal explants, excised from in vitro-grown seedlings. The best shoot proliferation was obtained on Murashige and Skoog (MS) medium supplemented with 8.0 ?M BA and 1.0 ?M GA<inf>3</inf>. Elongated shoots were rooted in MS medium, containing 12.0 ?M indole-3-butyric acid (IBA), and successfully acclimatated in greenhouse conditions. Microshoots, which underwent at least ten cycles of in vitro subculturing, were used in random amplified polymorphic DNA (RAPD) analysis in order to assess the maintenance of genetic fidelity to the donor plant A total of 624 amplified reproducible bands were produced from 10 random decamer primers out of 16; 76 were found to be polymorphic (producing polymorphisms ranging between 5.3 and 48.5%), and the average number of bands produced per primer was 6.2. The similarity matrix established through analysis of the band patterns ranged from 0.83 to 0.99 between the donor and micropropagated plants, and from 0.79 to 0.96 among cloned plantlets. The study suggests that somaclonal variations may be present in microshoots of pistachio which came from many cycles of axillary bud proliferation. © 2008 Elsevier B.V., All rights reserved.