Assessment of Intra-Specific Variation in Essential Oil Composition in Amomum subulatum Roxb. Cultivated in Uttarakhand, India

Large cardamom (Amomum subulatum) is native to Sikkim Himalaya and is important cash crop grown under the forest canopy. It thrives well between altitudes of 600 to 2000 m having an annual rainfall of 2500 to 5000 mm. Due to similar climatic condition and economic potential of the species, its cultivation was also started in Uttarakhand. Present study was design to analysis the chemical composition of essential oil and major compounds present in essential oil of capsule of A.subulatum grown in different agro-climatic region of Uttarakhand. The essential oil of 07 plant sample collected from different agro-climatic zones of Uttarakhand was analyzed through Gas Chromatography Mass Spectrometry (GCMS).The aroma analysis of chemicals present in essential oil was also carried out by two-fold, step wise dilution with dichloromethane. Oil yield was found between 2.5% to 3% for the sample of different agro-climatic regions. A total of 31 compounds were identified through Gas Chromatography Mass Spectrometry. 1-8 Cineol with 68% to 82.0% was the most dominant compound in all the samples. Other major compounds are 4-trimethyl (1.87% to 4.82%), β-pinene (1.88% to 3.56%), β-Terpineol (1.21% to 3.83%), Nerolidol (0.62% to 2.82%), DL limonene (1.01% to 2.51%) and Limonene (0.98% to 3.82%). Presence of higher concentration of essential oil (%) in all analyzed sample of Uttarakhand indicated that the species grown in Uttarakhand is may be of higher genotype. The GC-MS analysis of essential oil indicates quantitative variations within intra-specific and may attribute to the micro-climate under which the species grown.