Rhizobacteria and Silicon Synergy Modulates the Growth, Nutrition and Yield of Mungbean under Saline Soil

Osmotic stress and imbalance nutrients uptake due to salinity stress are major threats that cause decline in growth and yield of crops. This problem is very common in arid and semi-arid regions because of low precipitation and bad quality of irrigation water. Plants also produced higher level of stress generating ethylene via 1-aminocyclopropane-1-carboxylic (ACC) acid when cultivated under limited supply of water. However, inoculation of ACC deaminase producing plant growth promoting rhizobacteria (PGPR) can grant resistance against salinity to crops. On the other hand, silicon (Si) application also increase the productivity of the crop under salt induced stress. This study was conducted to examine the influence of sole and combined application of ACC-deaminase containing PGPRs and Si on mungbean under salinity stress. Prior to sowing, seeds were inoculated with peat based bacterial culture. Silicon was applied at 150 kg ha(-1) at the time of sowing using the source as CaSiO4 (Calcium Silicate). After two and half month's crop was harvested. Combined application of PGPR + Si caused a significant improvement in growth and physiological attributes of mungbean under salinity. A significant improvement in K (2.30, 0.33 and 0.52-fold) and reduction in Na concentration (0.66, 0.55 and 0.56-fold) in leaves, shoot and seeds, respectively, validated the efficacious role of combine application of PGPR and Si regarding mitigation of salinity stress in mungbean Significant increase in number of nodules, leaves and grain yield with PGPR + Si over control confirmed the ameliorative effect on mungbean under salinity stress. In conclusion, PGPR + Si is more effective compared sole application for enhancing growth, nutrients concentration and yield in mungbean under salinity stress.