APPLICATION OF BIOFERTILIZERS IN POTATO PRODUCTION

Abstract

The effect of inoculation with multi-strains inoculant containing Azotobacter vinelandii Al (asymbiotic N2-fixer), Bacillus megaterium F5 (phosphate dissolver), Bacillus circulans Tal (potassium dissolver), Pseudomonasjluorescens Asl(siderophores producer) andPseudomonasjluorescens G5 (antagonist against of Ralstonia solanacearum caused brown rot disease of potato plant) on growth, yield, NPK content and controlling potato rot disease in presence of different levels of nitrogen and potassium, and different sources of phosphate as a mineral fertilizers in pots and field experiments. A comparative study was carried out between different carriers materials (peatmoss, venniculite and rice husk) to evaluate their effect on the survival of five strains of bacteria used as multi- biofertilizers and biobactericide agent (during 90 days of storage at 5 and 30°C). The obtained results can be summarized in the following: 1 .One hundred and fifty Bacillus and eighty five Pseudomonas isolates were screened for selecting active P­ dissolving microorganisms having the capability to antagonize the bacterial pathogen Ralstonia solanacearum causing rot disease of potato plants.