Bio fertilization of Cereal and Legume Crops for Increasing Soil available P Uptake Using Nuclear Technique

Application of N and P in uncommon sources such as N2-fixers and AM fungi considered as an important source to save money and reduce pollution. In this concern, two pot experiments were carried out in sandy soils, to study the role of these neutral organisms in increasing the fertility of sandy soil. Wheat and faba bean were used. Seeds of wheat or faba bean were inoculated with Azotobacter or Rhizobium and planted in soils inoculated with and without AM fungi. A 20 mg P/kg soil in the form of single super phosphate (15.5 % P2O5) or rock-P (26.6% P2O5) were applied in the first experiment while KH2PO4 was added in the second one. Dry weight, spore number, root infection, total and specific P were also determined. Maximum shoot growth were gained when either, wheat or faba bean inoculated with mycorrhizae and N2-fixers relative to the control. it was reached to 54 and 73%, respectively. Phosphorus uptake for shoots of both wheat and faba bean had been significantly increased upon inoculating with AM and/or Azotobacter or Rhizobium. Addition of fertilizer P help to identify the P uptake from soil or fertilizer. Mycorrhizal plants induced significant increase in Pdff by about 39 and 27% over inoculated with Azotobacter for wheat and Rhizobium for faba bean and it reached to 95 and 79% when inoculated with combined inoculation. This may be due to AM fungi absorb more available P than do nonmycorrhizal roots. FUE was increased from about 5 to 10% for wheat; 6 to 19% for faba bean. It can be concluded that, bio fertilizers can increase crop production and soil fertility. Rock-P might be recommended as a source of P fertilizer to be applied with AM fungi. (Authors)