Kataria Sunita, Jain Meeta, Rastogi Anshu, Brestic Marian
School of Biochemistry, Devi Ahilya University, Khandwa Road, Indore, M.P., 452001, India.
Laboratory of Bioclimatology, Department of Ecology and Environmental Protection, Poznan University of Life Sciences, Piątkowska 94, 60-649, Poznan, Poland.
Photosynth Res. 2021 Dec;150(1-3):263-278. doi: 10.1007/s11120-021-00850-2. Epub 2021 Jun 1.
The study was performed to analyze the impact of seed pretreatment by static magnetic field (SMF) of 200 mT for 1 h on photosynthetic performance of soybean (Glycine max) seedlings under ambient (UV-B) and supplemental ultraviolet-B (UV-B) stress. Ambient and supplemental UV-B were found to decrease the plant growth, chlorophyll concentration, PSII efficiency, selected JIP-test parameters such as F/F, φEo, ΔV(I-P), PI, PI, and rate of photosynthesis in the leaves of soybean seedlings emerged from untreated (UT) seeds. UV-B and UV-B were observed to increase the synthesis of UV-B-absorbing substances (UAS), reactive oxygen species (ROS) like superoxide radical (O) and hydrogen peroxide (HO), antioxidants like ascorbic acid and α-tocopherol and decrease the nitrate reductase (NR) activity; subsequently, it results in a decreased rate of photosynthesis, biomass accumulation, and yield. However, our results provided evidence that SMF pretreatment increased the tolerance of soybean seedlings to UV-B radiation by increased NO content and NR activity; higher efficiency of PSII, higher values of φEo, ΔV(I-P), PI, and PI, decreased intercellular CO concentration, lower amount of UAS, ROS, and antioxidants that consequently improve the yield of soybean plants under UV-B as well as UV-B stress. Thus, our results suggested that SMF pretreatment mitigates the adverse effects of UV-B stress by the enhancement in photosynthetic performance along with higher NO content which may be able to protect the plants from the deleterious effects of oxidative stress caused by UV-B irradiation.
本研究旨在分析200 mT静磁场（SMF）预处理1小时对大豆（Glycine max）幼苗在环境（UV-B）和补充紫外线-B（UV-B）胁迫下光合性能的影响。发现环境UV-B和补充UV-B会降低由未处理（UT）种子萌发的大豆幼苗叶片的植株生长、叶绿素浓度、PSII效率、选定的JIP测试参数，如F/F、φEo、ΔV(I-P)、PI、PI以及光合速率。观察到UV-B和UV-B会增加紫外线吸收物质（UAS）、活性氧（ROS）如超氧自由基（O）和过氧化氢（HO）的合成，以及抗坏血酸和α-生育酚等抗氧化剂的合成，并降低硝酸还原酶（NR）活性；随后，这会导致光合速率、生物量积累和产量下降。然而，我们的结果表明，SMF预处理通过增加NO含量和NR活性提高了大豆幼苗对UV-B辐射的耐受性；PSII效率更高，φEo、ΔV(I-P)、PI和PI值更高，细胞间CO浓度降低，UAS、ROS和抗氧化剂含量降低，从而提高了UV-B和UV-B胁迫下大豆植株的产量。因此，我们的结果表明，SMF预处理通过提高光合性能以及更高的NO含量减轻了UV-B胁迫的不利影响，这可能能够保护植物免受UV-B辐射引起的氧化胁迫的有害影响。
