Plant growth promotion of millets under abiotic stress using enterobacter cloacae PR10(KP226575)

Plant growth promoting bacteria (PGPB) promote plant growth and crop yield. Millets constitute the staple food in parts of the world inhabited by the poor and food-insecure people. The crop yield of Millets is often affected by abiotic and biotic stress. The present work is focused on the enhancement of crop yield of Millets using PGPB. Enterobacter cloacae is a PGPB used in the present study targeted at five different millet cultivars. E. cloacae (KP226575) strain obtained from an organic farm at Sam Higginbottom University of Agriculture, Technology and Sciences (SHUATS), Allahabad, India, was isolated and screened for its plant growth promoting (PGP) traits. Further, the effect of the bacterial E. cloacae (KP226575) inoculation on growth variables of five millets cultivars at pH 6 to pH 9 was observed. The study indicated that Enterobacter cloacae (KP226575) possesses certain PGP traits like production of ammonia (NH³), hydrogen cyanide (HCN), siderophore (SD), indole acetic acid (IAA), 1-aminocyclopropane- 1carboxylate deaminase (ACCD), and phosphorus solubilization (PS). Besides, this strain showed tolerance to certain heavy metals like Al (>1600 mL⁻¹); Zn (> 400 μg mL⁻¹); Cr and Pb (>200 μg mL⁻¹) and As (>100 μgm L⁻¹) and certain trace elements like Mn and Mo (>1600-100 μg mL⁻¹ levels). The strain was also resistant to 11 antibiotics. In vivo experiments were carried out at SHUATS, Allahabad, under greenhouse conditions. Randomized complete block design with three replications was used for all trials. Inoculation of five millets cultivars with the E. cloacae (KP226575) showed a significant (p 0.01) increase in seed germination and enhanced root and shoot elongation, as compared to untreated control at pH 6 to pH 9. The study reveals the potential of E. cloacae (KP226575) strain for sustaining crop yield under abiotic stresses and development of crop-specific fertilizers.