Variation in the Essential Oil Yields and Compositions of Myrtle (Myrtus communis L.) Populations Collected from Natural Habitats of Southern Iran

As a medicinal and industrial plant, Myrtle (Myrtus communis L., Myrtaceae) has got numerous pharmacological, food, and cosmetic applications. In the current study, variabilities in the leaf essential oil (EO) compositions of 23 Myrtle populations, collected from the natural habitats of different regions in Fars Province, Iran, were studied. The EO yields of the populations varied from 0.53% (Polemord) to 1.75% (Bajgah) based on dry matter. According to GC/MS analysis, α-pinene (12.2-60.4%), 1,8-cineole (6.2-27.3%), limonene (1.4-26.7%), linalool (0.7-21.0%), myrtenyl acetate (0-29.1%), and geraniol (0.3-8.3%) were the major compounds. Using the hierarchical cluster analysis, the myrtle populations in Fars province were classified into four groups based on the main EO components, namely I α- pinene/1,8-cineole, II α-pinene/1,8-cineole/linalool, III α-pinene/limonene/1,8-cineole and IV myrtenyl acetate/limonene/linalool. Among the mentioned populations, the plants collected from Eram were characterized by possessing the highest concentration of myrtenyl acetate (29.09%); however, other populations were almost devoid of this compound. Additionally, a correlation was found between soil and climatic conditions of natural habitats and the main EO components. Therefore, clay- and silty-textured soils, organic matter, and altitude can be suggested to be the most important environmental factors affecting α-pinene and 1,8-cineole amounts in myrtle populations, while linalool content can increase with soil acidity. In conclusion, this study gave new insights into the breeding programs for obtaining potential plant materials through their commercial cultivations.