Evaluation of phosphate solubilizing bacteria as inoculants in maize

Abstract

Plant-growth promoting rhizobacteria (PGPR) have the ability to solubilize mineral phosphate in soil, as well as producing phytohormones, antibiotic and siderophores. The application of soil microbes that promote nutrition and development of plants provides new alternatives for increasing the yield of major agricultural crops. Three phosphate solubilizing bacteria were isolated from Puna (NOA) using as selection criteria P-solubilizing activity, growth in phosphorus limited concentration and siderophores production. They were identified as Serratia marcescens EV1, Pseudomonas tolaasii IEXb y Pseudomonas sp. SP28 (access number FM202483, FM202487, FM202488 respectively). The growth-promoter effect was determined by inoculating bacteria on maize plants grown under controlled conditions in glasshouse. Pseudomonas tolaasii IEXb was the strain with major capability to promote root and shoot development. Results from these experiments suggest that inoculation of PGPR with different beneficial properties, like P-solubilization, should be the future trends of bio-fertilizer application for sustainable crop production.