Isolated bacteria from saline–sodic soils alter the response of wheat under high adsorbed sodium and salt stress

This investigation was carried out for evaluation of indole-3-acetic acid production by bacteria under salinity and salinity–sodicity stress. A total of 298 bacteria were isolated from soils with different levels of electrical conductivity and sodium adsorption ratio. Then, ability of indole-3-acetic acid production under salinity, salinity–sodicity and l-tryptophan concentrations was analyzed. The results indicated that the ability of growth and indole-3-acetic acid production among bacteria was significantly affected by salinity, salinity–sodicity and l-tryptophan concentration. The one of the bacterial species, Arthrobacter siccitolerans, that were isolated from saline–sodic soils can adjust its indole-3-acetic acid production to different levels of salinity and salinity–sodicity stress conditions. Also, its l-TRP use efficiency under salinity–sodicity stress was 5.01% and reported as the most efficient bacterium. Seed inoculation of A. siccitolerans enhanced wheat aerial and root dry matter under salinity–sodicity stress with respect to control by 10.03 and 15.17%, respectively. The study indicates the different effects of salinity–sodicity on indole-3-acetic acid indole-3-acetic acid production and the potential of A. siccitolerans for production of indole-3-acetic acid and enhancing growth of wheat under salinity and salinity–sodicity stress.