Content and composition of the essential oil of Rosa alba L. during flower development

A. Dobreva, M. Gerdzhikova
Abstract. In 2010 the content and composition of the essential oil from Rosa alba L. in the different phases of the development of blossom is examined. Quantitative and qualitative changes of the essential oil are traced. Flowers from the population of white rose in 6 phases were investigated. The study was conducted at the Institute of roses and essential oil plants Kazanlak. It was found that optimum for the quantity and quality of the essential oil is not exactly at one time, but there is a correlation between the two indicators. The maximum content of essential oil is in phase IV – in semi-opened petals (in %). Optimal composition was recorded in (IV) and (V) phase, where the fundamental terpene alcohols: citronelol + nerol and geraniol are within limits, respectively 21,33 ÷ 22,19% and 8,11 ÷ 8,02% and the values of the ratio of terpene alcohols/hydrocarbons are the largest. White rose must be picked in semi-opened and opened flowers stage. After detachment of flowers processes of biosynthesis in the tissues continue and in storage both phases are matched. Thus optimal conditions for accumulation of maximum quantities of quality essential oil are created.