Quality evaluation of elite mint cultivars in two cropping seasons in subtropical conditions of Uttarakhand, India

Abstract

Mints (Mentha species) are being cultivated as an industrial crop for the production of their essential oils in northern Indian plains. In sub-tropical regions, Mentha species are cultivated as a spring–summer crop for their essential oils. However, for planting material production, these species are planted in the rainy season (August). The purpose of this study was to analyze and compare the essential oil quality of rain–winter crops (the planting material-producing crop) with the spring–summer crops (main crops) of Mentha spicata cv. MSS-5, Mentha spicata cv. Ganga, Mentha citrata cv. Kiran, Mentha arvensis cv. CIMAP-Saryu and Mentha x piperita cv. Kukrail. The essential oil yield varied from 0.40% to 1.10% in the main cropping season, whereas it varied from 0.15% to 0.60% in the planting material-producing cropping season. Gas chromatography (GC) and GC–mass spectrometry (GC–MS) analyses resulted in the identification of sixty constituents, representing 93.51–99.71% of the oil compositions. Monoterpenoids (77.33–98.14%) were the prevalent constituents of the essential oils, represented by menthol (38.64–78.21%), carvone (≤0.10–57.78%), piperitenone oxide (67.31–80.60%), linalool (≤0.10–44.16%), iso-dihydrocarveol acetate (1.79–42.26%), linalyl acetate (22.34–48.10%), menthyl acetate (3.79–38.31%), cis-dihydrocarvone (≤0.10–24.37%) and menthone (≤0.10–24.30%) in different mint cultivars. Substantial variations in the oil contents and compositions were noticed between spring–summer crop and rain–winter crop of the investigated mint cultivars.