Department of Biology, Faculty of Science, Urmia University, Urmia, 5756151818, Iran.
Department of Plant Production and Genetics, Faculty of Agriculture, Urmia University, Urmia, Iran.
Environ Sci Pollut Res Int. 2024 Aug;31(37):49498-49513. doi: 10.1007/s11356-024-34507-z. Epub 2024 Jul 30.
The issue of heavy metal pollution such as nickel poses a significant environmental concern, exerting detrimental effects on the growth and viability of plant life. Plants have various mechanisms to effectively manage heavy metal stress, including the ability to modify their amino acid type and content. This adaptive response allows plants to mitigate the detrimental effects caused by excessive heavy metal accumulation. The aim of this study was to investigate the effect of biofertilizers on nickel accumulation, nitrogen metabolism and amino acid profile of corn (Zea mays L.) cv. 'PL438' exposed to Ni stress. After disinfecting and soaking in water for 24 h, corn seeds were primed with bacterial biofertilizers (T2: NPK + FZ), fungal biofertilizers (T3: Arbuscular mycorrhizal fungi (AMF) + Trichoderma (T)), or a combination of them (T4: NPK + FZ + AMF + T) and were cultured by the hydroponic method in completely controlled conditions. Then, they were simultaneously exposed to nickel chloride at various rates (0, 75, or 150 µM) at the three-leaf stage. They were harvested two weeks later and were subjected to the measurement of Ni content, nitrate and nitrite content, nitrate reductase activity, and amino acid profile by high-performance liquid chromatography. The results showed that the application of Ni at higher rates increased Ni, nitrate, and nitrite contents and nitrate reductase activity. The study of Ni accumulation and TF revealed that Ni accumulated in the roots to a greater extent than in the shoots and TF was < 1 in all treatments. The shoot amino acid profile showed that the treatment of Ni increased som amino acids such as aspartic acid, asparagine, serine, histidine, and glycine versus the control, whereas T4 Ni increased aspartic acid, glutamic acid, threonine and arginine. The change in amino acids in Ni-treated plants may play a key role in their adaptation to Ni stress. The findings indicate that biofertilizers played a crucial role in mitigating the negative impacts of Ni on corn plants through alterations in amino acid composition and decreased absorption and translocation of Ni.
重金属污染问题，如镍污染，对植物的生长和生存能力造成了严重的环境影响。植物具有多种机制来有效地管理重金属胁迫，包括改变其氨基酸类型和含量的能力。这种适应性反应使植物能够减轻过量重金属积累造成的有害影响。本研究旨在探讨生物肥料对镍积累、氮代谢和氨基酸谱的影响玉米（Zea mays L.）cv。'PL438'暴露在 Ni 胁迫下。经过消毒和 24 h 水浸泡后，用细菌生物肥料（T2：NPK + FZ）、真菌生物肥料（T3：丛枝菌根真菌（AMF）+ Trichoderma（T））或它们的组合（T4：NPK + FZ + AMF + T）对玉米种子进行预培养，并通过水培法在完全控制的条件下进行培养。然后，在三叶期同时以不同浓度（0、75 或 150 μM）暴露于氯化镍。两周后收获，通过高效液相色谱法测定 Ni 含量、硝酸盐和亚硝酸盐含量、硝酸还原酶活性和氨基酸谱。结果表明，较高浓度的 Ni 应用增加了 Ni、硝酸盐和亚硝酸盐含量以及硝酸还原酶活性。Ni 积累和 TF 的研究表明，Ni 在根部的积累程度大于在地上部，并且在所有处理中 TF 均<1。地上部氨基酸谱表明，与对照相比，Ni 处理增加了天冬氨酸、天冬酰胺、丝氨酸、组氨酸和甘氨酸等氨基酸，而 T4 Ni 增加了天冬氨酸、谷氨酸、苏氨酸和精氨酸。Ni 处理植物中氨基酸的变化可能在其适应 Ni 胁迫中发挥关键作用。研究结果表明，生物肥料通过改变氨基酸组成和减少 Ni 的吸收和转运，在减轻 Ni 对玉米植株的负面影响方面发挥了关键作用。
