Effect of Endomycorrhizal Fungi, N2- Fixing Bacteria and Biological Potassium Fertilizer on the Yield and Quality of Nigella sativa in Calcareous Soil

Document Type : Original Article


 TWO FIELD experiments were carried out during winter seasons 2008/2009 and 2009/2010 at the Farm of Nubaria Agricultural Research Station. The aim of the work was to study the effect of the mycorrhizal fungus Glomus etunicatum, non-symbiotic N2-fixing bacteria (Halex), and Bacillus circulans, under different rates of mineral N, P, and K fertilizers (0, 25, 50, 75 and 100%) on the yield and quality of Nigella sativa plants growing in calcareous soil. The experiments were arranged according to a completely randomized split–plot block design with four replicates. The highest percentage of mycorrhizal root length colonization were 38.3% and 54.2% in case of plants inoculated with G. etunicatum in the presence of P75% and the mixture of inocula at the rate of NPK75 % of mineral fertilizers, respectively, whereas the un-inoculated plants ranged (18.4%). The highest percentage increase in NPK- uptake of shoots in case of inoculated Nigella plants with a mixture of inocula under the different rates of mineral NPK fertilizers compared to un-inoculated once. Significant increase was obtained in seed yield (534.4 kg/fed) in case of plants inoculated with a mixture of inocula (Halex, G. etunicatum and B. circulans), as compared to the un-inoculated plants (516.0 kg/fed ) in the presence of NPK75% of the recommended dose of NPK fertilizers. The highest significant value of fixed oil percentage was (34.7%) by inoculation mixture of inocula compared to un-inoculated once (33.0%) in the presence of NPK75% of the recommended dose of NPK-fertilizers. From the above mentioned results, it is clear the positive use of beneficial soil microorganisms on the plant growth and yield, in order to decrease using mineral fertilizers and chemical pollution.