Experimental site: The present study was conducted at the experimental farm of the CSIR-Institute of Himalayan Bioresource Technology, Palampur (1325 m amsl, 32° 06′ 05″ N, 76° 34′10″ E), India, in 2011. Minimum temperature ranges from 3.5 ℃ to 19.8 ℃, maximum temperature ranges from 15.2 ℃ to 31.4 ℃, relative humidity varies between 62.2% and 94.1% in the morning and 45.0% and 87.2% in the evening, and bright sunshine hour ranges from 2.9 to 8.9 hours. Plant material: A population of approximately 50,000 plants raised from mixed stem cuttings collected from perennial rose plantations at the University of Agriculture, Udaipur, Rajasthan, India, and maintained in the field of the CSIR-Institute of Himalayan Bioresource Technology, Palampur, Himachal Pradesh, India, were utilized as an original gene pool of R. damascena. Two varieties, Jwala and Himroz were diversified through selections of desirable traits (morphological/oil content) across 25,000 plants. The five elites, three of R. damascena var. Jwala, (Indica, Super jwala and Jwala) and two of R. damascena var. Himroz (Hot himroz and Himroz) were developed through field selections and maintained at the Natural Plant Products Division Experimental Farm of the Institute. Rosa bourboniana plants were collected from the Fragrance and Flavour Development Centre, Kannauj, UP, India, during 1992 and maintained at the Natural Plant Products Division Experimental Farm of the Institute.

The essential oil content of the varieties of R. damascena varied from 0.037% to 0.051% and that of R. bourboniana was 0.017%. Super jwala recorded the highest oil content (0.051%). A total of 32 components were identified in the different varieties of rose oil. These components constituted 78.1-93.5% of the total rose oil species. The main components of rose oil were citronellol + nerol (16.3-30.1%), geraniol (15.8-29.3%), linalool (0.7-1.9%), rose oxide (0.9-2.6%), phenyl ethyl alcohol (0.1-0.4%), eugenol (0.3-2.2%), nonadecane (7.3-14.7%). The content of citronellol + nerol (30.1%) and geraniol (29.3%) was the highest in Himroz compared with other varieties.