Climate-smart lemongrass (Cymbopogon khasianus (Hack.) Stapf ex Bor) yields quality essential oils consistently across cuttings and years in semi-arid, tropical southern India

Abstract

The study investigated the variation in the amount of essential oil and the composition of the lemongrass (Cymbopogon khasianus (Hack.) Stapf ex Bor) cultivar CIMAP Suwarna, obtained six times over three years, for morphological and chemical alterations. A gas chromatography and gas chromatography-mass spectrometry analysis was performed to chemically profile the essential oils, which found distinct chemical components in the essential oils. Plant height, tiller number, leaf number, leaf area, leaf breadth, leaf length, fresh weight, and essential oil yield all gradually rose. It also significantly increased oil production per plant. The concentration of citral in essential oil has been shown to have increased considerably. The findings showed a significant increase in the morphological characters affected by harvesting times, including plant height (C1) = 70.09–167.30 cm, tillers/plant (C2) = 10 to 38, no. of leaves/clump (C3) = 39 to 207, leaf width (C4) = 0.43–0.83 cm, leaf length (C5) = 31.82–59.87 cm, leaf area (C6) = 60.21–64.82 cm2, leaf area index (C7) = 0.033 to 0.043, and fresh herb yield/clump (C8) = 42.56–136.33g. However, they responded differently to individual cuts. In contrast to the preceding traits, the remaining five qualitative characteristics, namely C10–C14, have responded differently between cuttings. During the three years, some critical study factors had significant beneficial relationships with each other. Significant positive correlations existed in all three years between the essential features like C1 and C2; C1 and C3; C1 and C8; C2 and C3; C2 and C5; C2 and C8; C3 and C9; and C4 and C5 and C9. After 90–100 days of harvesting, a significant amount of high-quality citral ((Z)- and (E)-citral) essential oil was extracted. Finally, the lemongrass cultivar CIMAP Suwarna should be harvested after 90–100 days for a high concentration of high-quality citral essential oil. Therefore, for the highest essential oil content, yield, and citral content, the ideal harvesting period should be between 90 and 100 days. With continued climate change, the timing of lemongrass growth and maturity may be altered by weather and temperature fluctuations. Future agricultural practices may include climate-smart agriculture approaches to adapt to these changes. Farmers can use options like shifting planting times, changing watering systems, or implementing protective measures to reduce the influence of climate change on lemongrass growth and optimize harvesting dates. The potential for greater precision, efficiency, and decision-making in agricultural practices is highlighted by these future perspectives on the date of lemongrass harvesting. Farmers may optimize the timing of lemongrass harvesting to maximize yield, quality, and economic returns while guaranteeing sustainable farming practices by leveraging technical breakthroughs, genetic enhancements, and data-driven techniques. Kew wordsCutting; Cymbopogon khasianus; multi-cutting; (Z)- and (E)-citral; vitamin A; seasonal change.