Effect of Inoculation Growth Promotion Bacterium Pseudomonas putida on Tolerance to Salinity of Calotropis procera Ait. Seedlings

This study aimed to investigate the tolerance to salinity of Calotropis seedlings inoculated with the bacterium Pseudomonas Putida was conducted under greenhouse conditions. Treatments, six levels salinity stress factor with sodium chloride salt (0, 5, 10, 15, 20 and 25 ds/m) and two level inoculation factor (control and bacterium) as a factorial experiment in a completely randomized design with three replications was designed. Result showed that salinity more than 15ds/m, non-inoculation bacterium seedlings were dried. However, bacterium inoculated seedlings in 15 and 25ds/m salinity level respectively more than 50% and 38% their survival maintained. In non-salinity condition, height, root area, fresh and dry weight of seedling, respectively 2.59, 40.35, 38.05 and 31.89 percentage increase in the bacterium inoculated seedlings compared to non-inoculated was observed. In most salinity level until 15 ds/m of Inoculated seedlings, rate of photosynthesis and chlorophyll significantly increased as well as transpiration rate decreased. But electrolyte leakage did not any difference. So concentration of nitrogen, potassium and potassium to sodium of leaves bacterium seedlings compared to control were increased while sodium of leaves decreased. Overall, this research revealed that Seedlings inoculated to PGPB pseudomonas until moderate level of salinity specially 15 ds/m has provided most optimal performance and efficiency. Hence, using of this bacterium as a new biotechnologic approach could be suggested for Inoculation seedlings this species in reclamation of saline lands and production of its seedlings in nurseries with salty soils.