M. Layeghhaghighi; M. Hassanpour Asil; B. Abbaszadeh; F. Sefidkon; M. Matinizadeh
Abstract
About 67 species of the genus Nepeta have been found in Iran and Nepeta pogonosperma Jamzad is endemic to Iran. In order to investigate the effect of water deficit on Nepetapogonosperma, an experiment was conducted under field conditions in 2015, at the Alborz Research Station, Research Institute of ...
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About 67 species of the genus Nepeta have been found in Iran and Nepeta pogonosperma Jamzad is endemic to Iran. In order to investigate the effect of water deficit on Nepetapogonosperma, an experiment was conducted under field conditions in 2015, at the Alborz Research Station, Research Institute of Forests and Rangelands, Karaj, Iran. The experiment was conducted in a randomized complete blocks design with three replications. Treatments consisted of three levels: 30, 60, and 90% of field capacity. Harvesting was done in full flowering stage. Essential oil was extracted by distillation for 2 hours and 30 minutes. The percentage of essential oil components was determined using GC and GC/MS. In the Nepeta pogonosperma Jamzad essential oil, 16 components were identified and the highest percentage of 15 components including α-thujene, α-pinene, sabinene, β-pinene, myrcene, α-terpinene, ρ-cymene, e-β-ocimene, γ-terpinene, terpinen-4-ol, α-terpineol, 4aα,7α,7aα-nepetalactone, 4aα,7α,7aβ-nepetalactone, E-caryophyllene and β-bisabolene was related to the control treatment. Analysis of variance revealed that water deficit significantly affected the essential oil percentage, yield, and components detected. The highest essential oil percentage with an average of 3.18% belonged to the severe stress treatment (30% FC). The highest oil yield (78.321 kg per hectare) was recorded for the moderate stress treatment (60% FC). The highest content of 1.8-cineole belonged to 30% FC. The highest total content of nepetalactone with an average of 28.2% was obtained in the control group. Our results clearly showed that severe and moderate water deficit stress could be recommended for the production of plants with high essential oil content. However, no water deficit stress is recommended to obtain high content of nepetalactone.
