Drought is one of the major abiotic stresses to sustainable agriculture and global food security. The present study was conducted to evaluate the integrated effect of algal biochar (BC) and plant growth–promoting rhizobacteria (PGPR) on growth and physiology of maize under deficit irrigations. A pot experiment with different combinations of algal BC and PGPR under three deficit irrigations [field capacity (FC), 75% FC and 50% FC] was performed using maize as test crop. There were three controls without application of algal BC and PGPR under each water deficit irrigation. Both algal BC and plant growth–promoting rhizobacterial inoculation mitigated negative effects of deficit irrigations on maize performance, especially when applied in combined form. Under 50% FC, combined application of algal BC and PGPR significantly increased fresh and dry weights of shoot and root and root length by 2.76, 5.94, 3.24, 13.82, and 4.06 times compared to control, respectively. In case of physiological and nutrient uptake parameters, the same treatment caused the maximum increase in comparison to control. Post-harvest soil analysis also showed a positive treatment effect compared to their respective control. The combined application of algal BC and PGPR could be an effective strategy to improve growth and physiology of maize under deficit irrigations.

中文翻译：

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藻炭与植物促生根际细菌对缺水条件下玉米生理和生长的综合影响

干旱是可持续农业和全球粮食安全的主要非生物胁迫之一。本研究旨在评估藻类生物炭 (BC) 和促进植物生长的根际细菌 (PGPR) 在亏缺灌溉条件下对玉米生长和生理的综合影响。使用玉米作为试验作物，在三种亏缺灌溉 [田间持水量 (FC)、75% FC 和 50% FC] 下使用藻类 BC 和 PGPR 的不同组合进行盆栽试验。每个缺水灌溉下有3个未施用藻类BC和PGPR的对照。藻类 BC 和促进植物生长的根际细菌接种减轻了灌溉不足对玉米性能的负面影响，尤其是在以组合形式施用时。低于 50% FC，与对照相比，藻类BC和PGPR的联合施用显着增加了地上部和根的鲜重和干重以及根长分别为2.76、5.94、3.24、13.82和4.06倍。在生理和营养吸收参数的情况下，与对照相比，相同的处理引起最大的增加。与各自的对照相比，收获后的土壤分析也显示出积极的处理效果。藻类BC和PGPR的联合应用可能是改善亏缺灌溉下玉米生长和生理的有效策略。与各自的对照相比，收获后的土壤分析也显示出积极的处理效果。藻类BC和PGPR的联合应用可能是改善亏缺灌溉下玉米生长和生理的有效策略。与各自的对照相比，收获后的土壤分析也显示出积极的处理效果。藻类BC和PGPR的联合应用可能是改善亏缺灌溉下玉米生长和生理的有效策略。