Oliveira J P V, Pereira M P, Duarte V P, Corrêa F F, Castro E M, Pereira F J
Programa de Pós-graduação em Botânica Aplicada, Laboratório de Anatomia Vegetal, Departamento de Biologia, Universidade Federal de Lavras - UFLA, Campus Universitário, s/n, CP 3037, CEP 37200-000, Lavras, MG, Brazil.
Instituto de Ciências da Natureza, Universidade Federal de Alfenas - UNIFAL-MG, Rua Gabriel Monteiro da Silva, 700, Centro, CEP 37130-001, Alfenas, MG, Brazil.
Braz J Biol. 2018 Aug;78(3):509-516. doi: 10.1590/1519-6984.171961. Epub 2017 Nov 13.
Typha domingensis (cattail) is a native macrophyte known by its capacity to tolerate several heavy metals effects and the potential use for phytoremediation. However, in despite that cadmium (Cd) is one of the most toxic pollutants; its effects in T. domingensis biology remain uninvestigated. Thus, the objective of this study was to study the tolerance of T. domingensis to cadmium contamination by evaluating its growth, Cd uptake, leaf anatomy and gas exchange. The experiment was designed using three cadmium concentrations (0, 10 and 50 µM) and ten replicates for 90 days. The cadmium uptake, growth, gas exchange, chlorophyll content and leaf anatomy were evaluated. Data was submitted to ANOVA and Scott-Knott test for P<0.05. Typha domingensis accumulates Cd proportionally to its concentration on the solution and the content of this metal was higher in roots as compared to shoots. Plants showed no significant modifications on growth parameters such as the biomass production, number of leaves, number of clones and the biomass allocation to organs. The photosynthesis, transpiration and chlorophyll content were not modified by Cd. Most anatomical traits evaluated were not modified by the metal but the stomatal density and the proportion of vascular tissues were reduced under 50 µM of Cd. In despite, the leaf anatomy showed no toxicity evidences for any Cd level. The absence of growth reduction and the stability of anatomical and physiological traits give insight about the Cd tolerance of this species. Therefore, T. domingensis is able to overcome Cd toxicity and shows potential for phytoremediation.
香蒲是一种本地大型水生植物，以其耐受多种重金属影响的能力以及植物修复的潜在用途而闻名。然而，尽管镉是毒性最强的污染物之一，但其对香蒲生物学的影响仍未得到研究。因此，本研究的目的是通过评估香蒲的生长、镉吸收、叶片解剖结构和气体交换，来研究其对镉污染的耐受性。实验设计了三种镉浓度（0、10和50微摩尔），重复十次，持续90天。对镉吸收、生长、气体交换、叶绿素含量和叶片解剖结构进行了评估。数据采用方差分析和斯科特-诺特检验，P<0.05。香蒲对镉的积累与其在溶液中的浓度成正比，且根部的这种金属含量高于地上部分。植株在生长参数上没有显著变化，如生物量生产、叶片数量、克隆数量以及器官的生物量分配。光合作用、蒸腾作用和叶绿素含量未因镉而改变。所评估的大多数解剖特征未因金属而改变，但在50微摩尔镉处理下，气孔密度和维管组织比例降低。尽管如此，叶片解剖结构在任何镉水平下均未显示出毒性证据。生长未受抑制以及解剖和生理特征的稳定性揭示了该物种对镉的耐受性。因此，香蒲能够克服镉毒性，显示出植物修复的潜力。
