Rhizosphere and endophytic bacteria for induction of salt tolerance in gladiolus grown in sodic soils

Abstract

Extensive development of canal irrigation system led to formation of unproductive sodic lands, which limited the cultivation of flower crop gladiolus in the basins of major rivers. The purpose of this study was to isolate native rhizospheric and endophytic bacteria from sodic environment and evaluate their growth enhancement and bio-ameloirant properties in gladiolus under sodic soils. Sixteen isolates of plant-growth–promoting rhizospheric and endophytic 15 bacteria were isolated and screened for growth promotion potential. The promising strains were identified and evaluated for growth and production in gladiolus. The plants treated with strains CSR-G-1, CSR-B-2, and CSR-B-3 significantly produced marketable spikes and higher number of florets/spike. Also, the treated plants showed an increased activity of superoxide dismutase, phenyl alanine lyase, catalase, peroxidase, phenols, and proline than control. Further, the soil pH, total carbonates, and sodium adsorption ratio were lower in treated soils. The Na+/K+ ratio in leaves of treated plants 20 was observed to be lower than control. In conclusion, these bio-inoculums can be used as growth enhancer and bioameliorant in sodic soils as an eco-friendly management strategy.