Sawsan Abbas
GCSAR, Lattakia Research Center,
Tishreen University, Faculty of Agriculture, Biotechnology Division  Horticulture Department
2009

Abstract

The aim of the present study was the morphological and molecular characterizations and the evaluation of variability and genetic relationship of some R. damascene, R. canina and R. hybrida genotypes using PCR-based RAPD technique. According to our observations, there were some morphological differences in prickle density, leaf color, fruit and flower shape that allow differentiation between the three rose species studied. However, these morphological differences were inefficient for differentiation between the genotypes.
Total DNA was isolated from young green leaves of samples followed by running PCR reactions using 24 random primers. Polymorphism of investigated genotypes was observed in reactions with 19 tested RAPD primes which gave repeatable polymorphic products producing a total of 210 bands. The level of polymorphism amounted to 87.6% between the whole genotypes studied, while it amounted to 62.9% in case of R. damascena with a total of 143 bands. The results proved that RAPD was an efficient technique in discriminating between the studied genotypes collected from different areas and representing the genetic relationships in form of dendrogramm.
A successful and detailed in vitro propagation system for rapid micro-propagation of the Rosa damascena Mill.& Rosa canina L. has been developed. Single-node explants were surface sterilized and cultured on Murashige and Skoog medium (MS) supplemented with various combination of  growth regulators (IBA, NAA, BA, Kin and GA3) at different concentrations. Shoot proliferation was best on MS medium supplemented with 4.44µM BA + 0.49µM IBA + 0.58 µM GA3 with 3.17 microshoots per subculture every 4 weeks. Efficient rooting (100%) was achieved on half-strength MS medium with 4.9 µM IBA. Rooted plantlets were gradually acclimatized for 4 weeks and planted out under held conditions with a survival of over 75%.