Variation in growth, total phenolics, and essential oil composition of Rosmarinus officinalis L. under aquaculture and biofloc wastewater irrigation treatments in greenhouse cultivation

Abstract

With the growing shift toward sustainable and organic cultivation of medicinal and aromatic plants (MAPs), the use of nutrient-rich aquaculture wastewater for irrigation presents a promising alternative to conventional practices, offering both environmental and agronomic benefits. This study aimed to assess the variation in the growth parameters, total phenolics, essential oil yield, and composition of rosemary ( Rosmarinus officinalis L.) under different irrigation water quality treatments at two cuts. A greenhouse study was conducted using a completely randomized design with three treatments (T1: fertigation, T2: Biofloc wastewater, and T3: aquaculture wastewater) and three replicates. The study results showed significantly improved plant growth parameters, including plant height, number of side branches, fresh weight, and dry weight, in T1 compared with T2 and T3 in both cut 1 and cut 2. However, the phosphorus, potassium, and total phenolic contents in cut 2 were significantly higher in T3, followed by T2 and T1, respectively. The essential oil yield in cut 2 was higher than that in cut 1 across all the treatments. The three major essential oil constituents in all the treatments in both cuts were Artemisia ketone (30.42–47.15 %), Eudesm-7(11)-en-4-ol (15.18–19.52 %), and γ-Eudesmol (4.26–10.17 %) and T3 contained the highest total percentage concentrations of these essential oil constituents compared with T1 and T2. Moreover, these constituents had good representation on the principal component as indicated by their high Cos2 values. The findings of this study add new knowledge to the greenhouse cultivation of rosemary under organic production, and irrigation of aquaculture wastewater enhances the concentration of certain bioactive compounds in rosemary. • Plants irrigated with aquaculture effluents recorded higher concentrations of total phenolics. • Major essential oil constituents were higher in aquaculture effluent treatment. • The fertigation treatment resulted in improved morphological growth performance. • Plants at cut 2 had more essential oil yield than at cut 1.