5-Aminolevulinic Acid Ameliorates the Growth, Photosynthetic Gas Exchange Capacity, and Ultrastructural Changes Under Cadmium Stress in Brassica napus L.
5-Aminolevulinic Acid Ameliorates the Growth, Photosynthetic Gas Exchange Capacity, and Ultrastructural Changes Under Cadmium Stress in Brassica napus L.
复制标题
5-氨基乙酰丙酸改善甘蓝型油菜在镉胁迫下的生长、光合气体交换能力和超微结构变化。
DOI：
10.1007/s00344-013-9328-6
复制
发表时间：
2013-09-01
影响因子：
4.8
通讯作者：
Zhou, W. J.
中科院分区：
文献类型：
--
作者：
Ali, Basharat;Wang, B.;Zhou, W. J.
土壤中的重金属毒性是油菜（Brassica napus L.）生产的主要限制因素之一。克服这一限制的最佳方法之一是使用生长调节剂来诱导植物耐受性。研究了在温室条件下水培的油菜在三种浓度的镉（0、100和500μM）和三种叶面喷施水平（0、12.5和25mg l(-1)）下对镉（Cd）毒性与生长调节剂5-氨基乙酰丙酸（ALA）的组合的反应。镉会降低植物生长和叶子中的叶绿素浓度。叶面喷施 ALA 可改善植物生长并增加镉胁迫植物叶片中的叶绿素浓度。通过单独添加镉观察到光合参数显着降低。 ALA的施用提高了Cd胁迫下植物的净光合和气体交换能力。 ALA 还降低了芽和根中的 Cd 含量，而高浓度的 Cd 会升高 Cd 含量。不同Cd和ALA浓度下叶片叶肉细胞的显微研究表明，叶面喷施ALA显着改善了Cd效应，改善了叶片叶肉细胞的结构。然而，较高的Cd浓度（500μM）会完全破坏叶片结构，在这个水平上，细胞核和细胞间隙也没有建立；细胞膜和细胞壁相互融合。叶绿体完全受损并含有淀粉粒。然而，叶面喷施ALA改善了镉胁迫下的细胞结构，可见细胞结构有细胞核、细胞壁和细胞膜。这些结果表明，在15天的Cd胁迫下，施用ALA有助于改善油菜植物的生长、叶绿素含量、光合气体交换能力和叶片叶肉细胞的超微结构变化。
Heavy-metal toxicity in soil is one of the major constraints for oilseed rape (Brassica napus L.) production. One of the best ways to overcome this constraint is the use of growth regulators to induce plant tolerance. Response to cadmium (Cd) toxicity in combination with a growth regulator, 5-aminolevulinic acid (ALA), was investigated in oilseed rape grown hydroponically in greenhouse conditions under three levels of Cd (0, 100, and 500 mu M) and three levels of foliar application of ALA (0, 12.5, and 25 mg l(-1)). Cd decreased plant growth and the chlorophyll concentration in leaves. Foliar application of ALA improved plant growth and increased the chlorophyll concentration in the leaves of Cd-stressed plants. Significant reductions in photosynthetic parameters were observed by the addition of Cd alone. Application of ALA improved the net photosynthetic and gas exchange capacity of plants under Cd stress. ALA also reduced the Cd content in shoots and roots, which was elevated by high concentrations of Cd. The microscopic studies of leaf mesophyll cells under different Cd and ALA concentrations showed that foliar application of ALA significantly ameliorated the Cd effect and improved the structure of leaf mesophyll cells. However, the higher Cd concentration (500 mu M) could totally damage leaf structure, and at this level the nucleus and intercellular spaces were not established as well; the cell membrane and cell wall were fused to each other. Chloroplasts were totally damaged and contained starch grains. However, foliar application of ALA improved cell structure under Cd stress and the visible cell structure had a nucleus, cell wall, and cell membrane. These results suggest that under 15-day Cd-induced stress, application of ALA helped improve plant growth, chlorophyll content, photosynthetic gas exchange capacity, and ultrastructural changes in leaf mesophyll cells of the rape plant.