Irrigation dose and plant density affect the essential oil content and sensory quality of parsley (Petroselinum sativum)

Abstract

In the current study the influence of 3 irrigation treatments (ID0 as a control, ID1, and ID2), and 3 plant density treatments (PD0 as a control, PD1, and PD2) were investigated on the production (total yield), volatile composition of essential oil, and sensory quality of parsley (Petroselinum sativum). The results showed that the highest plant yield was obtained when using the highest values of both irrigation dose (ID2 = 1788 m3 ha−1) and plant density (PD2 = 7.41 plants m−2). Hydrodistillation technique was used to extract the essential oil of parsley shoots and GC–MS and GC-FID were used to identify and quantify the components of the essential oil, respectively. The results showed that the main compounds of the essential oil were β-phellandrene, 1,3,8-p-menthatriene, myristicin, myrcene, terpinolene, limonene, α-pinene, and α-phellandrene. The treatment ID1 (861 m3 ha−1) led to the highest concentrations of most of the main compounds: 1,3,8-p-menthatriene (150 mg kg−1), myristicin (46.8 mg kg−1), and myrcene (33.7 mg kg−1); a similar pattern was found for the plant density PD0 (5.56 plants m−2), with contents being 1,3,8-p-menthatriene (143 mg kg−1), β-phellandrene (130 mg kg−1), and myristicin (38.1 mg kg−1). Aroma attributes, such as parsley-like, citrus, and green grass significantly had the highest intensities in ID1 and PD0 plants. The final recommendation based on all data generated is to use the irrigation dose of 861 m3 ha−1 (ID1) and the plant density of 5.56 plants m−2 (PD0) for better yield and quality of the final product under the assayed conditions.