Bacterial isolates Achromobacter, Ochrobactrum Pseudomonas, and Variovorax have often been isolated from plant roots, and most of them have been described as growth enhancing rhizobacteria. These rhizobacteria have been used to boost crops productivity in varied region of agro-climatic regions. To lessen the usage of chemical fertilizers inputs and improve the sustainability of rice–wheat crops, this study was planned to investigate the impacts of bacterial consortium inoculants producing 1-aminocyclopropane-1-carboxylate (ACC) deaminase on plant growth, nutrient content and grain yield in a field trial. Rice and wheat plants subjected to plant growth-promoting rhizobacteria (PGPR) consortia of strain DPC9 (Ochrobactrum anthropi) + DPB13 (Pseudomonas palleroniana) + DPB15 (Pseudomonas fluorescens) + DPB16 (Pseudomonas palleroniana) gave the best results with reference to macronutrient—nitrogen, phosphorus, potassium, calcium and sodium content and yield-related parameters including 1000 grain weight (10.2%, 40.7%), number of grains per panicle/spike (45.5%, 60.6%), and tillers (32.2%, 106.6%). This inoculants significantly increased grain yield (65.6%, 74.4%), straw yield (26.8%, 36.9%) and harvest index (14.9%, 13.8%) of rice–wheat crops, respectively, when compared to their counterpart control plants. Significant positive correlation in parameters which contribute in producing high grain yield in rice–wheat include plant height (r = 0.938, r = 0.852), tillers (r = 0.968, r = 0.881), panicle/spike length (r = 0.844, r = 0.912), number of grains per panicle/spike (r = 0.969, r = 0.815), 1000 grain weight (r = 0.833, r = 0.931), straw yield (r = 0.920, r = 0.918) and harvest index (r = 0.909, r = 0.847) and also surge nutrient enhancement in rice and wheat were observed in consortium treated plants. It can be concluded that consortium of DPC9 + DPB13 + DPB15 + DPB16-producing ACC deaminase can serve as a useful bio-inoculant for sustainable rice–wheat production in diverse agro-ecosystem.
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