Isolation and Characterisation of Indigenous Phosphate Solubilising Microbes and their Probiotic Potentials in Malawi Aquatic Ecosystems

Abstract

Phosphate solubilizing microbes (PSM) were isolated from the rhizosphere of different aquatic plants, water and benthic soils of aquatic ecosystem with the aim of having cheap and environmental friendly biofertiliser and probiotics. Extensive research has been performed with respect to PSM isolation from the rhizospheres of various plants in different locations, but little is known about the in-depth of PSM and their probiotic potential in Malawi aquatic ecosystem.  Isolates were screened on the basis of solubilizing inorganic Phosphorous (P) using Pikovskaya’s media, soil and rock supplemented. Molecular characterization of the conserved genes (16S rRNA and 18S rRNA) and biochemical test were employed in taxonomic analysis. Candidacy of strains was primarily based solubilisation index of more than 3 complimented by production of diverse plant growth promoting, bioremediation and probiotic traits. The selected strains with commercial implications were identified as Alcaligenes ammonioxydans, Enterococcus faecium, Citrobacter braakii, Enterobacter cancerogenus, Geotrichum sp. and Aspergillus sibiricus. Isolates showed higher solubilisation values In-vitro through synergistic effect of co-inoculation. The present compilation of these diverse diazotrophs along with P solubilisation, probiotic and plant growth promoting traits potentially suggests that these indigenous microbes can be exploited as biofertilisers. The present study explores potentiality of indigenous microbe’s ability to solubilize insoluble phosphates like tricalcium, aluminium, and iron phosphate for development of biofertiliser.