Induced growth promotion under in vitro salt stress tolerance on solanum lycopersicum by fluorescent pseudomonads associated with rhizosphere

Saline stress in soil and strategic management of soil salinity is a major issue of agriculture sector in many countries. Application of plant growth promoting pseudomonads is a known way of approach, in order to protect the plants from detrimental effects caused by salinity. In this study, the ability of pseudomonads to combat the in vitro saline stress in tomato plants is checked. Pseudomonads from rhizosphere samples using 8-hydroxy quinolone were isolated and biochemically characterized. Isolates were also checked for their plant growth promotion traits, such as IAA, siderophore, hydrogen cyanide and ammonia production, and phosphate solublization. Isolates were tested in tomato seedlings under normal condition. Fifteen isolates were shortlisted based on direct and indirect plant growth promotion traits, and tested on tomato plants under 3ds, 6ds and 9ds saline conditions. A marginal increase in germination percentage, vigour index and dry weight was shown by the tested isolates under different saline conditions. Initial study on isolates offer promising saline stress tolerance agents, which can be further tested.