Topic: diversity

Mints are one of the most popular herbs in Al -Madinah Al Munawwarah region – Saudi Arabia. Mentha longifolia is the most common species grown in Al -Madinah which is locally known as Al -Madinah mint (locally known as Hassawi and Habaq). The fresh plant is traditionally used as herbal drink by extraction in boiled water as a flavoring agent with hot tea. Also, in traditional medicine it is widely used for treatment of many gastrointestinal disorders (El -badry, Al -ali, & El -badry, 2010) and respiratory disorders. The M. longifolia essential oil showed antioxidant antimicrobial, antispasmodic, and decongestant activities (Iqbal, HussainChatha, Naqvi, & Bokhari, 2013). Most studies done on Mentha species is confined on medical and pharmaceutical aspect, or chemical composition and properties of its essential oils. Very few studies done about Mentha longifolia in Saudi Arabia. But no published data discuss Mentha microbiome. A metagenomicis quite helpful approach that reveals both culturable and unculturablendophytic microbial communities (Dinsdale et al., 2008). It avoids the need for isolation and cultivation of individual species (Kaul et al., 2016). Usinmetagenomics in studying the diversity of Mentha microbiome will provide better understanding of Mentha longifolia growth requirements and shall evaluate the high potential of the endophyte community in promoting plant growth and yield and enhancement of plant stress tolerance in different conditions. The Metagenomics studies have improved our understanding of the diversity of microbes in various habitats including plants (AkinsanyaGoh, Lim, & Ting, 2015b). Such studies are important to illuminate endophytes confer stress tolerance and growth Mentha spp. are the most popular herbs that widely used in Saudi Arabia. Mentha longifolia is the most common species grown in Al -MadinaAl -Munawwarah region which is locally known as Al -Madinah mintHassawi and Habaq. Large number of researches were performed to support the use of M. longifolia as a traditional popular herbal tea drink both in fresh and dried form. As well as a folk remedy due to many benefits for human health (Farzaei et al., 2017; Mikaili, Mojaverrostami, Moloudizargari, Aghajanshakeri, 2013) .2.1.1 Mentha longifolia Essential OilAmong the various types of compounds, essential oils from aromatic and medicinal plants are receiving particular attention due to their great benefits. Essential oils are very complicated mixtures of natural compounds quite different concentrations (Bozin, Mimica -Dukic, Simin, & Anackov, 2006). Reports showed that many factors interfere with essential oil composition of the different Mentha members. Among these factors, the habitat environment (growth location, soil characteristics), climatical (moisture presence, temperature, etc.), seasonal, and geographical conditions of the regions where the species grow. As well as phenological factors (phase of the plant collection), plant part used for essential oil extraction (flowers, stems, leaves, entire aerial parts or inflorescences), type of material (fresh or dry), and even methods used for essential oil extraction. In addition to environmental stress which can negatively affect the quality of mint essential oils (Hussein, El -Sherbeny, Hendawy, El Gohary, & Ghazal, 2014; Iqbal et al., 2013; Kr?giel et al., 2018).