Cadmium tolerance of Typha domingensis Pers. (Typhaceae) as related to growth and leaf morphophysiology

Abstract

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. Keywords

Comparação da retenção de cádmio e chumbo nos tecidos vegetais das macrófitas aquáticas aguapé (Eichhornia sp.) e taboa (Typha sp.) por biossorção e fitorremediação

“…O acúmulo preferencial de metais nas raízes do Aguapé e da Taboa ocorre pelo processo de precipitação e co-precipitação realizada pela ação de microrganismos que se propagam em sua rizosfera e são responsáveis pela imobilização e remoção dos metais por essas plantas (SYUKOR et al, 2016). Além disso, para Typha sp., o acúmulo de metais em suas raízes está relacionado às barreiras protetoras (apoplastos) presentes nas raízes que impedem o transporte dos poluentes para os tecidos fotossintéticos (LYUBENOVA et al, 2012;OLIVEIRA et al, 2018).…”

“…solução nutritiva de Hoagland e Arnon a 30% (v/v)(DAS, GOSWAMI e DAS TALUKDAR, 2016;OLIVEIRA et al, 2018), pH na faixa de 5,0 a 6,0, temperatura de 25 ± 2 ºC e fotoperíodo de 12 horas. As plantas ficaram em período de aclimatação por 21 dias e a reposição da água perdida por evapotranspiração ocorreu a cada dois dias.Após o período de aclimatação, foram selecionadas plantas filhas do Aguapé e da Taboa com tamanhos e pesos semelhantes.…”

Response of Corchorus olitorius Leafy Vegetable to Cadmium in the Soil

“…This shows a tolerable concentration range of 5–15 and 5–20 mg/kg for non-essential toxic Cd element in C. olitorius , where beyond its growth was inhibited, thus displaying both hormetic and toxic responses towards Cd contamination in the soil [ 18 ]. These findings are related to insignificant changes in the number of new shoots in Typha domingensis plants exposed to toxic Cd in the soil [ 33 ]. Similarly, the root length of Hylotelephium spectabile, a Cd-accumulating species, was not affected by exposure to 5–10 mg/L Cd [ 34 ].…”

Potential of Colletotrichum typhae H.C Greene mycoherbicide for bio-control of Southern cattail (Typha domingensis Pers.) plants

“…Typha domingensis Pers. is an invasive macrophyte found in the Americas, Europe, Africa, Asia and Oceania, being considered as a native species of South America, occurring throughout Brazil (Oliveira et al, 2017). It is propagated either by seeds or vegetatively, by rhizomes, with vigorous growth by the decomposition and assimilation of organic matter as a source of nutrients, reaching about seven tons of rhizomes per hectare (Rangel-Peraza et al, 2017).…”