The experiments were conducted for the estimation of the mitigating effect of the static magnetic field (SMF of 200 mT for 1 h) treatment on soybean under ambient UV-B stress. The SMF treated (MT) and untreated (UT) seeds were grown inside iron cages covered with polyester filters for the purpose to filter UV-A + B (< 400 nm) and UV-B (< 300 nm) radiations, polythene filter control (FC) transparent for UV (280-400 nm), and open controls (OC) were without any filters. Our results indicated that specific leaf weight, efficiency of PS II, activity of carbonic anhydrase (CA) and nitrogenase (NRA), nucleic acid and protein content, nitric oxide (NO) and yield were significantly decreased in plants of untreated seeds under UV-B stress. SMF treatment to the soybean seeds was observed to mitigate the adverse effect of ambient UV-B with a significant enhancement in above-measured parameters in plants when compared with plants of untreated seeds grown under OC/FC conditions. Chlorophyll a fluorescence transition curve (OJIP-curve) from SMF treated and UV excluded plants has shown a higher fluorescence yield especially for I–P phase as compared to the plants grown in ambient UV-B stress. Reduction in the level of superoxide anion radicle (\({\text{O}}_{2}^{{ \cdot^{ - } }}\)), hydrogen peroxide (H₂O₂), malondialdehyde (MDA) and proline content with a remarkable increase in DNA, RNA, protein and NO content, increased photosynthetic efficiency and nitrogen fixation in the leaves of soybean suggested the ameliorating effect of SMF pre-treatment against ambient UV-B induced damage. Consequently, SMF-pretreatment increased the tolerance of soybean seedlings to ambient UV-B stress as compared to the untreated seeds. The increase in carbon and nitrogen fixation ability due to SMF pre-treatment and the omission of solar UV radiation impact can be a direction for the purpose to improve the crop yield. Evaluation of the consequences of SMF treated seeds under ambient UV-B stress, and the plants from untreated seeds under solar UV exclusion indicated parallelism among the two effects.

中文翻译：

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一氧化氮和活性氧在静磁场预处理中的作用诱导大豆对环境 UV-B 胁迫的耐受性。


进行实验的目的是评估静磁场（200 mT SMF，1 h）处理对环境 UV-B 胁迫下大豆的缓解效果。 SMF 处理 (MT) 和未处理 (UT) 种子在覆盖有聚酯过滤器的铁笼内生长，用于过滤 UV-A + B (< 400 nm) 和 UV-B (< 300 nm) 辐射，聚乙烯过滤器控制(FC) 对 UV (280-400 nm) 透明，开放对照 (OC) 没有任何滤光片。我们的结果表明，未经处理的种子在紫外线照射下的植物的比叶重、PS II 效率、碳酸酐酶 (CA) 和固氮酶 (NRA) 活性、核酸和蛋白质含量、一氧化氮 (NO) 和产量均显着降低。 B压力。据观察，与在 OC/FC 条件下生长的未处理种子的植物相比，对大豆种子进行 SMF 处理可减轻环境 UV-B 的不利影响，并且植物中上述测量参数显着增强。与在环境 UV-B 胁迫下生长的植物相比，经 SMF 处理且排除 UV 的植物的叶绿素a荧光转变曲线（OJIP 曲线）显示出更高的荧光产量，特别是在 I-P 阶段。降低超氧阴离子自由基 ( \({\text{O}}_{2}^{{ \cdot^{ - } }}\) )、过氧化氢 (H ₂ O ₂ )、丙二醛 (MDA) 水平大豆叶片中的 DNA、RNA、蛋白质和 NO 含量显着增加，光合效率和固氮能力提高，表明 SMF 预处理对环境 UV-B 诱导的损伤具有改善作用。因此，与未经处理的种子相比，SMF 预处理提高了大豆幼苗对环境 UV-B 胁迫的耐受性。 SMF预处理提高固碳固氮能力，消除太阳紫外线辐射影响，可以成为提高作物产量的一个方向。对 SMF 处理的种子在环境 UV-B 胁迫下的后果以及未经处理的种子在太阳紫外线排除下的植物的评估表明，两种效应之间存在平行性。