Institute of Plant Nutritional Physiology and Molecular Biology, College of Resources and Environment, Fujian Agriculture and Forestry University (FAFU), Fuzhou 350002, China.
Institute of Materia Medica, Fujian Academy of Medical Sciences, Fuzhou 350002, China.
Int J Mol Sci. 2017 Dec 3;18(12):2570. doi: 10.3390/ijms18122570.
Limited data are available on the sulfur (S)-mediated-alleviation of aluminum (Al)-toxicity in higher plants. seedlings were irrigated for 18 weeks with 0.5 mM MgSO₄ or 0.5 mM MgSO₄ + 0.5 mM Na₂SO₄, and 0 (-Al) or 1 mM AlCl₃·6H₂O (+Al, Al-toxicity). Under Al-toxicity, S decreased the level of Al in leaves; increased the relative water content (RWC) of roots and leaves, the contents of phosphorus (P), calcium (Ca) and magnesium (Mg) per plant, the dry weights (DW) of roots and shoots, the ratios of root DW/shoot DW, and the Al-induced secretion of citrate from root; and alleviated the Al-induced inhibition of photosynthesis via mitigating the Al-induced decrease of electron transport capacity resulting from the impaired photosynthetic electron transport chain. In addition to decreasing the Al-stimulated H₂O₂ production, the S-induced upregulation of both S metabolism-related enzymes and antioxidant enzymes also contributed to the S-mediated-alleviation of oxidative damage in Al-treated roots and leaves. Decreased transport of Al from roots to shoots and relatively little accumulation of Al in leaves, and increased leaf and root RWC and P, Ca, and Mg contents per plant might also play a role in the S-mediated-alleviation of Al-toxicity.
有关硫（S）缓解高等植物铝（Al）毒性的资料有限。在 18 周的时间里，幼苗分别用 0.5 mM 的 MgSO₄或 0.5 mM 的 MgSO₄+0.5 mM 的 Na₂SO₄和 0（-Al）或 1 mM 的 AlCl₃·6H₂O（+Al，Al 毒性）进行灌溉。在 Al 毒性下，S 降低了叶片中的 Al 水平；增加了根和叶的相对含水量（RWC）、植物中磷（P）、钙（Ca）和镁（Mg）的含量、根和茎的干重（DW）、根 DW/茎 DW 的比值以及根中柠檬酸的 Al 诱导分泌；并通过减轻 Al 诱导的光合电子传递链受损导致的电子传递能力下降，缓解了 Al 对光合作用的抑制。除了降低 Al 刺激的 H₂O₂产生外，S 诱导的 S 代谢相关酶和抗氧化酶的上调也有助于减轻 Al 处理的根和叶中的氧化损伤。从根部向茎部转运的 Al 减少，叶片中 Al 的积累相对较少，叶片和根的 RWC 以及植物每单位 P、Ca 和 Mg 的含量增加，这可能也在 S 缓解 Al 毒性中发挥了作用。
