Salinity has become one of the major factors limiting agricultural production. In this regard, different cost-effective management strategies such as the use of plant growth-promoting bacteria (PGPB) as inoculants to alleviate salt-stress conditions and minimize plant productivity losses have been used in agricultural systems. The aim of this study was to characterize induced antioxidant responses in corn through inoculation with Azospirillum brasilense and examine the relationship between these responses and the acquired salt-stress tolerance. Treatments were performed by combining sodium chloride (0 and 100 mM NaCl) through irrigation water with absence and presence of A. brasilense inoculation. The experiment was performed in a completely randomized design with four replications. Lipid peroxidation (malondialdehyde [MDA]), and nitrogen (N), sodium (Na⁺) and potassium (K⁺) contents, as well as dry biomass, glycine betaine, and antioxidant enzymes activities such as of superoxide dismutase (SOD, EC 1. 15. 1. 1), glutathione reductase (GR, EC 1. 6. 4. 2), guaiacol peroxidase (GPOX, EC 1. 11. 1. 7), and glutathione peroxidase (GSH-PX, EC 1. 11. 1. 9) were determined. Overall results indicated that plants treated with 100 mM NaCl showed the most pronounced salt-stress damages with consequent increase in MDA content. However, inoculated plants showed an enhanced capacity to withstand or avoid salt-stress damages. These results could be attributed, at least in part, to the increased activity of antioxidant enzymes. Our results suggest that A. brasilense may confer tolerance to salt stress in corn plants enhancing antioxidant responses, primarily by the enzymes GSH-PX and GPOX, and the osmolyte glycine betaine.

盐分已成为制约农业生产的主要因素之一。在这方面，农业系统中使用了不同的具有成本效益的管理策略，例如使用植物生长促进细菌 (PGPB) 作为接种剂以缓解盐胁迫条件并最大程度地减少植物生产力损失。本研究的目的是通过接种巴西固螺菌来表征玉米中诱导的抗氧化反应，并检查这些反应与获得的盐胁迫耐受性之间的关系。通过将氯化钠（0 和 100 mM NaCl）通过灌溉水与A. brasilense不存在和存在结合来进行处理接种。实验以完全随机的设计进行，重复四次。脂质过氧化（丙二醛 [MDA]）、氮 (N)、钠 (Na ⁺ ) 和钾 (K ⁺) 含量，以及干生物量、甘氨酸甜菜碱和抗氧化酶活性，如超氧化物歧化酶 (SOD, EC 1. 15. 1. 1)、谷胱甘肽还原酶 (GR, EC 1. 6. 4. 2)、愈创木酚测定了过氧化物酶（GPOX，EC 1. 11. 1. 7）和谷胱甘肽过氧化物酶（GSH-PX，EC 1. 11. 1. 9）。总体结果表明，用 100 mM NaCl 处理的植物表现出最明显的盐胁迫损害，MDA 含量随之增加。然而，接种的植物表现出增强的承受或避免盐胁迫损害的能力。这些结果至少部分归因于抗氧化酶活性的增加。我们的结果表明A. brasilense 可能赋予玉米植物对盐胁迫的耐受性，增强抗氧化反应，主要是通过酶 GSH-PX 和 GPOX，以及渗透物甘氨酸甜菜碱。