Effects of Methanol Sprays on Essential Oil and Phenol Yields and Vegetative Characteristics of Lavender

An experiment in the form of single factor ANOVA was conducted to study the effects of spraying methanol on essential oil yield and vegetative characteristics of the medicinal plant lavender. The treatments included three levels of methanol (Zero percent or C, the control), 10% (M10), and 20% (M20), and 40% (M40) methanol. A Clevenger-type apparatus extracted the Essential oil. Results showed the highest essential oil yield (1.4%) the maximum wet and dry leaf weight (4.2 and 16 grams per plant, respectively), and the tallest plants (24.56 centimeters) were obtained in the M20 treatment. There were significant differences among the treatments in the length and width of leaves, with the largest leaf length and width belonging to the M20 treatment. The maximum leaf surface areas were observed in the M10 and M20 treatments with 124.6 and 128.6 square centimeters, respectively. The highest dissolved leaf phenol content (171.5?gg^(-1) fw) was also observed in the M20 treatment. Therefore, it can be concluded that methanol application increased essential oil yield and improved the measured vegetative features, that the M20 treatment had greater stimulating effects compared to the other treatments, and that the effects of the M40 treatment were not significantly different from those of the control.