(132) Study on Morphological Characteristics and Essential Oil Constituents Bulgarian Oil-bearing Rose

Bulgaria is famous for its 330-year-old-tradition in rose oil production, which is based on the Kazanluk rose ( Rosa damascena Mill. f. trigintipetala Dieck.). The Bulgarian rose oil (otto) is recognized as the ultimate rose oil. For successful selection and breeding work of oil-bearing roses, information is needed on the variation of morphological and phenological characteristics and essential oil composition of locally available genotypes. We estimated the correlation coefficients between yields and morphological characteristics of 15 genotypes of Bulgarian oil-bearing rose. It was found that rose yields depended mostly on the number of flowers, the number of flower branches per bush, and the weight of individual flowers ( r = 0.99, 0.88, and 0.84, respectively). Also, we established correlations between the concentrations of various essential oil constituents of the Bulgarian rose oil. Generally, higher concentration of citronellol + nerol was associated with lower concentration of geraniol and stereo-terpens ( r = –0.76 and –0.59, respectively). Also, higher concentration of citronellol + nerol was positively correlated to increased concentration of terpene aldehydes ( r = 0.63) and esters ( r = 0.48). The geraniol concentration was positively correlated to stearoptenes ( r = 0.57). Both morphological characteristics and essential oil constituents should be used for further selection of high-yielding cultivars with desirable essential oil composition.