Comparing hydroponic and aquaponic rootzones on the growth of two drug-type Cannabis sativa L. cultivars during the flowering stage
Metadata:
type: 📥
- Cite key: yepComparingHydroponicAquaponic2020
- Tags: ⭕, review, aquaponics
- Item Type: Article
- Authors: Brandon Yep, Nigel V. Gale, Youbin Zheng
- Date: 2020
- Date Added: 2021-02-05
- DOI: 10.1016/j.indcrop.2020.112881
zotero_url: * Local library - PDF Attachments
Abstract
The cultivation of drug-type Cannabis sativa Lin. (C. sativa) employs a variety of rootzone systems, yet little is understood about rootzone-effects on plant physiology, inflorescence biomass, and cannabinoid potency. To determine if rootzone systems can affect C. sativa growth, physiology, and inflorescence biomass and phytochemicals, two C. sativa cultivars, colloquially known as ‘Nordle’ and ‘Sensi-Star’, were grown in three rootzone systems in a controlled environment. The three tested rootzone systems were: 1) an 11-litre pot containing a peat-based growing substrate, top fertigated with a synthetic fertilizer solution (“hydroponic”); 2) an 11-litre pot containing a peat-based growing substrate, top fertigated with aquaculture effluent solution (“aquaculture”); and 3) a 3-litre pot containing a custom made, predominantly peat-based growing substrate, with the lower portion of the roots submerged in a conventional aquaponics deep-water culture system (“aquaponics”). Throughout the experiment, plant growth (height, branch number, canopy volume), leaf-level physiological traits (e.g., chlorophyll) foliar mineral nutrition, and substrate physio-chemical properties were measured. At experimental completion, inflorescence yield (dry biomass) and potency (mass-based cannabinoid and terpene concentrations) were determined. Results revealed, significant rootzone-effects on most growth and physiological traits measured. Plants performed best in the in the hydroponic rootzone: e.g., producing 42–116% greater inflorescence biomass than the other rootzone systems. In contrast, however, Nordle plants in the aquaponics treatment had greater Δ9-tetrahydrocannabinolic acid (THCA), cannabidiolic acid (CBDA), and the terpenes ß-pinene and limonene, relative to their congeners grown in the other rootzones investigated. Pronounced differences in substrate macro-nutrient availability and foliar nutrient content occurred among the rootzones, suggesting a potential mechanism to explain the observed growth, physiological, yield and potency responses. This work underscores the importance of the rootzone environment for the cultivation of C. sativa, specifically in indoor systems focused of medical or research production.