Abstract
The use of new agricultural technologies such as soilless and aeroponic cultivation systems is a valuable approach to medicinal plant production. The present study investigated the prospects of enhancing yield and secondary metabolite production in Valeriana jatamansi under aeroponic cultivation using elicitors, such as yeast extract and methyl jasmonate. Plants were evaluated by measuring growth parameters, photosynthetic rate, and secondary metabolites contents (on a dry weight basis). Maximum plant height (36.83 cm), leaf number (17.67), rootlet number (37.33), and rootlet length (6.90 cm) were observed at 0.5 mg/L yeast extract treatment; whereas treatment levels of 1.5 mg/L yeast extract and 150 µM methyl jasmonate resulted in maximum leaf length (6.95 cm) and leaf width (5.43 cm), respectively. Maximum photosynthetic rate (5.4053 µmol m-2s-1) and stomatal conductance (0.0656 mmol m-2s-1) were recorded at treatment levels of 0.5 mg/L and 1.5 mg/L yeast extract respectively, whereas at 150 µM methyl jasmonate treatment, transpiration rate was 0.9046 mmol m-2s-1. In aeroponic cultivation, the maximum content of valerenic acid and hydroxy valerenic acid was detected in leaf (2.47 and 8.37 mg/g) and root (1.78 and 7.89 mg/g) at treatment levels of 100 µM and 150 µM methyl jasmonate, respectively. Acetoxy valerenic acid was highest in leaf (1.02 mg/g) at 1.5 mg/L yeast extract, and in the root (2.38 mg/g) at 150 µM methyl jasmonate. Gas chromatography-mass spectrometry analysis identified twenty-eight volatile compounds in roots, of which three—isovaleric acid (6.72-50.81%), patchouli alcohol (13.48-25.31%) and baldrinal (0.74-25.26%)—were the major constituents. The results revealed that, besides roots, leaves could also be utilized as a prominent alternative source for targeted secondary metabolites. In conclusion, aeroponic cultivation offers year-round quality biomass production and ease to access subsequent roots harvest in V. jatamansi, to meet the demand of the pharmaceutical industries.
Highlights
A plethora of chemically diverse natural medicinal biomolecules is derived from Himalayan herbs
Morphological traits varied in terms of plant growth parameters, i.e. the coefficient of variation in aeroponic and pot cultivations ranged from 1.84% to 17.27%
In aeroponic and pot cultivations, coefficient of variation (CV) values interpreted in percentage (%) were, respectively: plant height 12.62, 11.99; leaf number 22.55, 11.89; leaf length 4.05, 2.42; leaf width 4.48, 5.93; rootlet number 15.23, 15.11 and rootlet length 7.98, 7.28
Summary
A plethora of chemically diverse natural medicinal biomolecules is derived from Himalayan herbs. Due to its medicinal potential, it is commercially used in the pharma-sector for the remedy of hysteria, nervous unrest, asthma, insomnia, cholera, leprosy, and nervous disorders (Hiller and Zetler, 1996; Agnihotri et al, 2011; Bhatt et al, 2012; Joseph et al, 2016; Jugran et al, 2019). The major metabolites, such as valerenic acid (VA), acetoxy valerenic acid (AVA), and hydroxy valerenic acid (HVA) are accumulated mainly in the roots and rhizomes of the Valeriana species (Navarrete et al, 2006; Singh et al, 2006). In India, the market price of dried rhizome and roots of V. jatamansi valued at Rs. 440 per kg, and the estimated annual trade is 10002000 metric tons (Goraya and Ved, 2017)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
