EFFECT OF CYANOBACTERIA, AND PHOSPHATE DISOLING BACTERIA INOCULATION ON IMPROVING PEANUT PRODUCTIVITY IN PRESENCE OR ABSENCE OF DIFERENT RATES OF ROCK PHOSPHAE FERTILIZER UNDER SANDY SOIL CONDITION

A field experiment was carried out in a sandy soil at EL- Ismailia Agric. Res. Station,   EL- Ismailia Governorate, (A R C), Giza, Egypt, during the summer season of 2005 to study the effect of inoculation with cyanobacteria and phosphate dissolving bacteria (PDB) viz. Bacillus megatherium var. phosphaticum, each alone or both in combination and\or when the inoculation was accompanied with different rates of rock phosphate fertilizer as a natural source of phosphorus on peanut productivity, NP&K uptake of peanut seeds and foliage and the soil total count bacteria, actinomycetes and fungi. Results revealed that inoculation with cyanobacteria and\or PDB each alone or both in combination increased peanut pods weight, seeds and foliage yields, N, P and K contents for both peanut seeds and foliage compared to uninoculated treatments. Also, the combination of both microbial inoculation and rock phosphate fertilizer at any rate increased significantly these parameters than those received either inoculation or rock phosphate each alone. At flowering stage, generally, the inoculation with either cyanobacteria or Bacillus and\or their combination increased the soil total count of bacteria, actinomycetes and fungi compared to those recorded by uninoculated treatments and those recorded initially and harvest for all the other tested treatment. Generally, the use of 600 kg fed^-1 rock phosphate fertilizer along with inoculation with cyanobacteria and Bacillus was superior to those received microbial inoculation only, or rock phosphate fertilizer at the rates of 200 and 400 kg fed^-1 only and\or their combination with dual inoculation with cyanobacteria and Bacillus. This microbial inoculation/rock phosphate integration helps in the fast solubilization of the insoluble phosphate found in rock phosphate that may lead to reduce the cost and the environmental pollution due to the extensive use of the mineral fertilizers.