Abstract
DUE to increasing importance of roses in producing secondary products including essential boils and pharmaceutical compounds as phenolics, several protocols were developed from different explants of roses. For that purpose, an efficient callus initiation procedure for Rosa damascena Mill. cultivated in Taif, KSA was developed by using petal explant cultures supplemented with nine elicitors for improving phenolics content. As well, related genetic expression variation of the elicited calli was studied by biochemical (protein and isozyme) analyses. Except for rose and geranium oils, seven elicitors increased the phenolics content in R. damascena calli compared with the control. High qualitative differences were observed in their banding patterns reflecting biochemical aberrations in treated calli. A dendrogram, based on UPGMA method of cluster analysis, upheld the notable fluctuations in phenolics content and gene expression occurred by different elicitors.