Cadmium (Cd) is highly toxic metal for plant metabolic processes even in low concentration due to its longer half-life and non-biodegradable nature. The current study was designed to assess the bioremediation potential of a Cd-tolerant phytobeneficial bacterial strain Bacillus sp. SDA-4, isolated, characterized and identified from Chakera wastewater reservoir, Faisalabad, Pakistan, together with spinach (as a test plant) under different Cd regimes. Spinach plants were grown with and without Bacillus sp. SDA-4 inoculation in pots filled with 0, 5 or 10 mg kg⁻¹ CdCl₂-spiked soil. Without Bacillus sp. SDA-4 inoculation, spinach plants exhibited reduction in biomass accumulation, antioxidative enzymes and nutrient retention. However, plants inoculated with Bacillus sp. SDA-4 revealed significantly augmented growth, biomass accumulation and efficiency of antioxidative machinery with concomitant reduction in proline and MDA contents under Cd stress. Furthermore, application of Bacillus sp. SDA-4 assisted the Cd-stressed plants to sustain optimal levels of essential nutrients (N, P, K, Ca and Mg). It was inferred that the characterized Cd-tolerant PGPR strain, Bacillus sp. SDA-4 has a potential to reduce Cd uptake and lipid peroxidation which in turn maintained the optimum balance of nutrients and augmented the growth of Cd-stressed spinach. Analysis of bioconcentration factor (BCF) and translocation factor (TF) revealed that Bacillus sp. SDA-4 inoculation with spinach sequestered Cd in rhizospheric zone. Research outcomes are important for understanding morpho-physio-biochemical attributes of spinach-Bacillus sp. SDA-4 synergy which might provide efficient strategies to decrease Cd retention in edible plants and/or bioremediation of Cd polluted soil colloids.

镉 (Cd) 由于其较长的半衰期和不可生物降解的性质，即使在低浓度下也是植物代谢过程中剧毒的金属。目前的研究旨在评估耐镉植物有益细菌菌株芽孢杆菌的生物修复潜力。SDA-4，从巴基斯坦费萨拉巴德的 Chakera 废水库中分离、表征和鉴定，以及在不同 Cd 状态下的菠菜（作为试验植物）。菠菜植株有和没有增长芽孢杆菌属。在装有0、5或 10 mg kg ^-1 CdCl ₂掺入土壤的盆中接种 SDA-4 。不含芽孢杆菌sp. SDA-4 接种，菠菜植物表现出生物量积累、抗氧化酶和养分保留减少。然而，用芽孢杆菌接种的植物。SDA-4 显示出显着增强的生长、生物量积累和抗氧化机制的效率，伴随着 Cd 胁迫下脯氨酸和 MDA 含量的降低。此外，芽孢杆菌的应用。SDA-4 帮助受镉胁迫的植物维持必需营养素（N、P、K、Ca 和 Mg）的最佳水平。据推断，特征性的耐镉 PGPR 菌株，芽孢杆菌sp. SDA-4 具有减少 Cd 吸收和脂质过氧化的潜力，从而保持营养的最佳平衡并促进 Cd 胁迫菠菜的生长。生物浓缩因子 (BCF) 和易位因子 (TF) 的分析表明，芽孢杆菌属。SDA-4 接种菠菜在根际区域隔离 Cd。研究成果对于理解菠菜芽孢杆菌的形态-生理-生化特性很重要。SDA-4 协同作用可能提供有效的策略来减少可食用植物中的 Cd 保留和/或 Cd 污染的土壤胶体的生物修复。