Enhancement of Growth, Yield and Chemical Constituents of Rosemary (Rosmarinus officinalis, L.) Plants by Application of Compost and Biofertilization Treatments

This investigation was carried out at the Experimental Farm of Fac. of Agric. Al-Azhar Univ. Assiut, Egypt during two successive seasons of 2010 / 2011 and 2011 / 2012. The research aimed to study the effect of compost levels (10,15 and 20 ton/fed) and some biofertilizers namly Azotobacter Chroococcum & Azospirillum brasilense (Azo.), Bacillus megaterium var. phosphaticum (B.M) alone or in a mixture with or without compost on growth, yield, and chemical constituents of Rosmarinus officinalis, L. plants. The results showed that, in both seasons at all cuts, the highest values plant height; number of branches; herb fresh and dry weights, and essential oil ( percentage and yield) as well as N, P & k % were given by adding compost at 20 ton/ fed compared to control and other compost treatments. In regard to bio-fertilizer treatments, all of them led to increase the growth, yield and essential oils %. The best results in terms of these characters were obtained due to inoculating the plants with Azo. + B.M In most cases, the combined effect of compost and bio-fertilizer treatments on Rosmarinus officinalis, L. plants parameters was statistically significant. In general, inoculating the plants with Azo. + B.M plus compost at 20 ton/ fed. and Azo. plus 15 ton/fed., respectively were the most effective treatments concerning growth, yield, as well as, chemical constituents and the percentage of the main compounds in the essential oil (camphene , 1.8 – cineole, and borneol).