Enhancing the survival of sugarcane infected white leaf disease by using bacterial indoleacetic acid producers

Effects of bacterial indole acetic acid (IAA) producers (BIPs) on plant growth and recovery of sugarcane seedlings infected with phytoplasmas associated with white leaf disease (SWLD) were examined. Seven bacterial isolates showed β-indole acetic acid production in culture medium supplemented with tryptophan. Interestingly, two of them (BC17 and BTII2) produced the highest β-indol acetic acid after 4 days of culture. Treatment with two bacterial isolates of SWLD infected sugarcane plants also showed differences in height of sugarcane seedlings, while a gradual symptoms reduction decreased the plant mortality compared to non-treated plants as control. BIPs were shown to be efficient biofertilizer inoculants that promoted plant growth and also reduced the damage of phytoplasma-associated diseases at the sugarcane seedling stage.