PLANT GROWTH-PROMOTING BACTERIAL MIXTURE ENHANCED GROWTH OF BARLEY UNDER SALT STRESS

Salinization is a primary environmental stress limiting global plant growth and production. Barley (Hordeum vulgare L.) is a cereal grain used as important food source in many countries. Inoculation with plant growth -promoting bacteria (PGPB) is a method for alleviating the harmful effects of salt stress on plant growth. This study focused on the impact of salinity on growth parameters, soluble sugars and individual amino acids of barely plants. In addition, to demonstrate the role of the mixture of PGPB (Pseudomonas putida and Bacillus subtilis) to ameliorate the growth in response to salt stress. There was a significant decrease of growth parameters of barley plants grown in hydroponic cultures supplemented with 100 mM NaCl. This suppression was associated with a significant increase of Na+ and Na+/K+, trehalose and sucrose content compared to control plants. The total amnio acids and free individual amino acids content markedly decreased in response to salt stress. Treatment of barley grains with mixture of PGPB significantly enhanced plant growth in salinized hydroponic cultures. The data suggested that the mixture of PGPB may be induced changes of cellular osmotic potential which enhance the growth of barley plants in response to salt stress.