Sulfur nutrition of deciduous trees
Sulfur nutrition of deciduous trees
复制标题
落叶乔木的硫营养
DOI：
--
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
H. Rennenberg
中科院分区：
文献类型：
--
作者：
C. Herschbach;H. Rennenberg
摘要。硫的还原形式（-II）是生长发育的必需营养素，但主要以硫酸盐的氧化形式提供给植物。落叶树通过根从土壤溶液中吸收硫酸盐，并通过根和叶的同化硫酸盐还原作用将硫酸盐还原为硫化物。为了在叶片中还原，硫酸盐被装载到木质部并运输到茎部。在叶绿体中未被还原或储存在液泡中的多余硫酸盐和在叶片中未被用于蛋白质合成的剩余S被装载到韧皮部并运回根。沿着运输路径，硫酸盐和谷胱甘肽（GSH）从韧皮部卸下，储存在木质部和韧皮部薄壁以及坑细胞和射线细胞中。从储存组织中重新动员的S在春季被装载到木质部，但在季节后期似乎不存在韧皮部到木质部的交换。因此，只有在季节变化时才会出现S型的自行车池。韧皮部中硫酸盐：谷胱甘肽的比例似乎参与了S营养的调节。这张S营养图与温带落叶乔木的不同生长模式，即(1)终止生长模式，(2)周期性生长模式和(3)不确定生长模式，以及与环境变化的关系进行了讨论。
Abstract. Sulfur in its reduced form (-II) is an essential nutrient for growth and development, but is mainly available to plants in its oxidised form as sulfate. Deciduous trees take up sulfate by the roots from the soil solution and reduce sulfate to sulfide via assimilatory sulfate reduction in both roots and leaves. For reduction in the leaves, sulfate is loaded into the xylem and transported to the shoot. The surplus of sulfate not reduced in the chloroplast or stored in the vacuole and the surplus of reduced S not used for protein synthesis in the leaves is loaded into the phloem and transported back to the roots. Along the transport path, sulfate and glutathione (GSH) is unloaded from the phloem for storage in xylem and phloem parenchyma as well as in pit and ray cells. Re-mobilised S from storage tissues is loaded into the xylem during spring, but a phloem to xylem exchange does not appear to exist later in the season. As a consequence, a cycling pool of S was only found during the change of the seasons. The sulfate:glutathione ratio in the phloem seems to be involved in the regulation of S nutrition. This picture of S nutrition is discussed in relation to the different growth patterns of deciduous trees from the temperate climate zone, i.e. (1) terminated, (2) periodic and (3) indeterminate growth patterns, and in relation to environmental changes.