A new chemotype of palmarosa [Cymbopogon martini (Roxb.) W. Watson] identified from ‘The Aravali Range’ of Rajasthan, India

An exploration was conducted to Aravali range of Udaipur, Rajasthan wherein wild palmarosa covering the entire hills was noticed. Observation of the plants revealed entirely different aroma compared to cultivated palmarosa. Hence, detailed investigation was carried out in this genotype for morphological, yield and quality parameters with released variety of palmarosa vir. PRC-1 as check. Two years observation revealed that though the Udaipur chemotype is short and bushy, it recorded significantly highest dry biomass yield, essential oil content and essential oil yield (0.67 kg/pt, 1.04% and 6.97 mg/pt, respectively) compared to cultivated palmarosa (0.52 kg/pt, 0.93% and 4.8 mg/pt, respectively). Further, morphological characterization carried out based on collar, auricle and ligule of the leaf and involucral bract of the inflorescence revealed no significance variation between these two accessions. However, GC/MS analysis of the essential oils of these two accessions showed entirely different spectra of chemical compounds. The major component of essential oil in cultivated palmarosa is geraniol (78.29%) and geraniol acetate (6.16%) whereas, it's Udaipur chemotype contains limonene epoxide (22.1%), trans carvyl formate (17.31%), limone-10-ol (17.21%), d-limonene (12.95%), dihydro linalool acetate (9.3%), limonene epoxide (5.31%) as the major components. As the newly identified chemotype is wildly distributed in Aravali hills of Udaipur, it can be commercially utilized for its essential oil, once its industrial utility is established and it can also be utilized in palmarosa breeding programme.