Effect of different levels of irrigation on quantitative and qualitative factors of rosemary (Rosmarinus officinalis)

Some medicinal plants are drought tolerance and irrigation shortage not only do not damage the plant but also increase the quality of secondary metabolites in this group of plants. In order to investigate the effect of irrigation shortage stress on the quantity and quality of rosemary, an experimental study was conducted in a randomized complete block design with four treatments and three replications in the research greenhouse of Imam Khomeini International University. Experimental treatment included different levels of irrigation (۱۰, ۲۰, ۴۰ and ۶۰% of field capacity or FC). For this purpose, rooted cuttings with uniformed shape and size were prepared and planted in pots. After complete establishment of the plant, experimental treatments were applied. Plant growth factors were measured weekly. At the end of the experiment, samples of plant branches were harvested and essential oil was extracted by using Clevenger. The oils obtained from three distillations of each treatment were injected to GC and GC/MS. The results showed that different levels of irrigation had a significant effect on the number of branches per plant, so that the highest number of branches was obtained in the treatment of irrigation with ۴۰% of field capacity, but there was non-significant difference in plant height, stem diameter and leaf length and width. Essential oil percentage, leaf chlorophyll content and essential oil compositions were affected by experimental treatments so that the highest percentage of essential oil (۱.۲%), the highest amount of chlorophyll (۵۶.۶۱ mg / g), alpha-pinene (۱۲.۲ %), ۱-۸-cineole (۱۱.۵%) and camphene (۹.۶%) were obtained in plants under irrigation with ۶۰% FC.

کلیدواژه ها:

Essential oil ، Field capacity ، Growth factors