Biomass, content, yield and chemical composition of mint (Mentha x villosa Huds.) essential oil in response to withholding irrigation

Abstract

The current work aimed at evaluating the influence of withholding irrigation on biomass production, content, yield and chemical composition of mint essential oil. The experimental design was completely randomized with five treatments and eight repetitions; totally forty plots; being conducted in pots inside a greenhouse for 58 days. The treatments consisted of withholding irrigation (NS) at different levels: control (daily constant irrigation at day zero by withholding irrigation), light NS (withholding irrigation for three days before harvesting), intermediate NS (withholding irrigation for six days before harvesting), severe NS (withholding irrigation for nine days before harvesting) and very severe NS withholding irrigation for twelve days before harvesting). Then, the following characteristics were evaluated: shoot fresh mass (SFM), shoot dry mass (SDM), root fresh mass (RFM), root dry mass (RDM), root volume (RV), conten, yield and chemical composition of mint essential oil. Results indicated that some characteristics were affected by withholding irrigation, such as SFM RFM, RDM, RV and some essential oil components (i.e. 3-octanol; linalool; limonene; p-cymen-8-ol; 3-octanol, acetate; cis-β-ocimene and cis-Piperitone epoxide). However, there was no significant difference between content and yield. Therefore, the current study showed that suppressing irrigation for 12 days before harvesting (very severe NS) did not affect plant development, since mint is commercialized in dry form.