SYNERGISTIC INTERACTION OF BRADYRHIZOBIUM AND ARBUSCULAR MYCORRHIZAL FUNGI WITH LEVELS OF MINERAL NITROGEN, PHOSPHORUS AND MOLYBDENUM ON PEANUT GROWN IN SANDY SOILS

Abstract

A field experiment was conducted in the newly reclaimed sandy soils at El-Bostan area, to investigate the influence of bio and mineral fertilizers on yield and yield components of peanut plants (Arachis hypogaea L.). Treatments include single or dual inoculation of Bradyrhizobium (BR) and the vesicular-arbuscular mycorrhizal fungi (VAM), as biofertilizers. In addition, eight mineral fertilizer treatments, nitrogen (75, 100 and 120% of recommended dose), phosphorus (50, 75 and 100% of recommended dose) and two molybdenum treatments (with 200 g ha-1 Mo as ammonium molybdate and without) under randomize complete block statistical design (RCBD). The results indicate that inoculation with VAM+BR significantly increase hundred kernel weight, kernel, pods, hay and biological yield by 34.00, 26.12, 45.81, 26.80 and 34.32 %, respectively compared to uninoculated treatments followed by single treatments of BR then VAM. Data also revealed that bacterial–mycorrhizal–legume symbiosis increase significantly VAM infection and number of spores, nodule number and BR count, nitrogenase activity and alkali phosphatase compared with uninoculated. Also, the plant nitrogen, phosphorus and potassium (NPK) concentrations, protein content and shelling percentage were significantly increased due to dual biofertilizers followed by the single inoculation. Application of molybdenum increased nodules number per plant and BR count by 4.35 and 10.97% when compared with without molybdenum application. Generally, inoculation with VAM and BR can, synergistically, remove the deficient effect of N and P in the soil of low nutrient content. At the same time, increase the NUEs and PUEs. Bio-Dependency of pods, hay and biological yields increased significantly by 29.70, 36.89 and 45.87; 15.08, 21.02 and 26.93; and 20.76, 27.18 and 34.28%, respectively with inoculation with VAM, BR and VAM+BR.