Inoculation of Salt-Tolerant Acinetobacter sp (RSC9) Improves the Sugarcane (Saccharum sp. Hybrids) Growth Under Salinity Stress Condition

A study was conducted to examine the effect of locally isolated rhizospheric strain, Acinetobacter sp RSC9, on sugarcane plant growth, under salt stress glasshouse conditions. The selected isolate in this study was characterized based on morphology, cultural, biochemical and molecular level and identified as Acinetobacter sp RSC9 (accession number KX168051). Screening of plant growth-promoting traits revealed that the strain is able to produce IAA, solubilize phosphate, potassium and zinc and fix atmospheric nitrogen under 1% and 2% NaCl stress conditions. In a pot experiment study supplemented with 1% NaCl, the alleviation of salt stress and plant growth parameters such as plant height, the number of leaves, root fresh/dry weight and shoot fresh/dry weight were significantly improved compared to positive control. In 1% NaCl, the sugarcane treated with Acinetobacter sp RSC9 showed 39.62% and 10.22% improvement in shoot and root length, respectively, compared to the control plant. Acinetobacter sp RSC9 also showed a higher fresh weight of shoot (69.68%) and root (69.94%) in 1% NaCl salt-stressed plants. In the case of 2% NaCl, there was no seed germination due to higher salt stress; however, the pot inoculated with Acinetobacter sp RSC9—showed 100% germination. It reveals that Acinetobacter sp RSC9 has protected the plant from salinity stress and showed corresponding enhancement in growth parameters studied. Overall, the present study depicts that the Acinetobacter sp. RSC9 strain could be used as a biofertilizer for sugarcane crops grown in saline soils.