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Abstract The production of aromatic and medicinal plants has been extensively focused in the last few years. There is a return back to use herbs in pharmaceuticals and cosmetics. However, studying the factors affecting production of such plants is paramount. Recently, great efforts have been devoted for increasing and improving the productivity of medicinal and aromatic plants in both quality and quantity. Medicinal and aromatic plants are important economic products which represent significant agricultural export products (Watt and Breyer, 1962). Ocimum gratissimum L. is one of those plants widely known and used for both medicinal and nutritional purposes. It is a perennial plant that is widely distributed in the tropics of Africa and Asia. It belongs to the family Labiatae (Lamiaceae) and it is the most abundant of the genus Ocimum. The common names of the plant are basil fever plant or tea bush and vernacular names include Daidoya ta gida (Hausa), Nehonwu (Igbo), tanmotswangiwawagi (Nupe) and efinrin (Yoruba) (Abdullahi et al., 2003). The plant belongs to the genus of Ocimum (basil) and a species of Ocimum gratissimum. It is woody at the base and has an average height of 1-3 meters. The leaves are broad and narrowly ovate, usually 5-13cm long and 3-9cm wide. It is a scented shrub with lime-green leaves (USDA, 2008). The fresh aboveground parts of O. gratissimum contain 0.8-1.2% essential oil. The chemical composition of the oil is variable and at least 6 chemotypes have been reported, characterized by the main components of the essential oil: eugenol, thymol, citral, ethyl cinnamate, geraniol and linalool. An overview of the occurrence of the various types and possible implications for the taxonomy is lacking. The eugenol type is the most important economically; the thymol type is formerly important, but most thymol is now produced synthetically, while natural thymol is mostly obtained from Thymus vulgaris L. or Trachyspermum ammi (L.) Sprague ex Turrill. The other types are of little economic importance. O. gratissimum is grown for the essential oil in its leaves and stems. Eugenol and to a lesser extent, thymol extracted from the oil are substitutes for clove oil and thyme oil. Poison: The essential oil is also an important insect repellent, medicine: The whole plant and the essential oil have many applications in traditional medicine, especially in Africa and India. Preparations from the whole plant are used as stomachic and in treating sunstroke, headache and influenza. Fertilizers is one of the most important factors limiting the productivity of aromatic and medicinal plants especially N,P and K, as these elements play an important role in the physiological processes of plant growth and partake in structure of many compounds in plant as carbohydrates, proteins ,amino acids ,nucleic acids , phospholipids..etc. (Devlin, 1975). The intensive use of expensive mineral fertilizers in recent years causes environmental pollution problems. Also, the use of chemical fertilizers at extremely high dose for a long period decreased the potential activity of micro-flora and the stability of soil organic matter (Pokorna, 1984). Biofertilizers are produced and practiced in different countries as well as in Egypt. They are nitrogen fixer’s i.e.Rhizobia, Azotobacter, Azospirillum and algae or phosphate solubilizing microorganisms (bacteria and mycorrhiza). Utilized biofertilizers could supply plants with their needs of nitrogen and phosphorus during their by cheap means, which in turn decrease the application of expensive mineral fertilizers and lead to significant decrease in production costs of the different crops. In addition, pollution rates in soil, water and air could be lowered by using of biofertilizers as a result of decreasing the extensive using of chemical fertilizers (Alaa El-Din, 1982). Bacterial strains are highly efficient on promotion of N fixation, CO2 evaluation and ammonification resulting in adjustment of pH media than using each of in single application (Awad, 1998) .The potential of vesicular-arbuscular mycorrhizal (VAM) soil fungi to improve plant nutrition and yield (Bethlenfalvay and Miguel Berea, 1994) to protect plants from pathogens and to improve plant resistant to environmental stress. Microbein as a commercial biofertilizers contain N-fixing bacteria that enhancing the plant growth and oil productivity via increasing the soil fertility. Organic fertilizers are very important for fertilizing the different soils by way the mode of their action lies in improving the physical and chemical characters of soils by their contents from organic acids, sugars, organic matter, cytokinins and nutrients (Abou El-Fadl et al., 1968). To increase the crops quality especially medicinal and aromatic plants, organic fertilization is more acceptable than chemical fertilizers and organic forming is a quality standard to be matched well by small farmers in Egypt (Abou El- Fadl et al., 1990).Thus, the biofertilizers and organic fertilizers are considered cheap feasible alternatives for the expensive chemical fertilizers that cause environmental pollution. Growth media composition is an important factor affecting the performance of the growing plants. It should be provided by adequate and balanced water and nutrients, an abundant oxygen supply for capillary root growth, favorable osmotic tension and reaction that maintain water and nutrients exchange. These properties should be combined to prepare a cheap, low time and labour consuming substrate (Nelson, 1991 |