<b>Cadmium toxicity on seed germination and seedling growth of wheat <i>Triticum aestivum

Abstract

ABSTRACT. Cadmium toxicity in seed germination and seedling growth of wheat (Triticum aestivum, is assessed. The ecotoxicological effects of six experimental concentrations of cadmium (0.03; 0.06; 0.12; 0.6; 1.2; 2.4; 4.8 mM), and control were evaluated. All assays were performed in quadruplicates with 25 seeds per replication in Petri dishes. Responses for toxic effect comprised the variables germination percentage, index of velocity of germination (IVG), length of aerial section and root of the seedlings, green and dry mass of the seedlings. Results showed that T. aestivum seeds exposed to cadmium decreased their normal germination percentage as from 0.03 mM concentration, with a 31% reduction of germination percentage and a 20% decrease in IVG. Cadmium´s inhibition effect on initial growth of seedlings influenced growth of roots and aerial part as from concentration 0.12 mM and reduced the production of green and dry mass of seedlings as from 0.06 mM. The presence and accumulation of cadmium in the soil cultivated with T. aestivum may trigger liabilities in productivity and/or viability caused by its toxicity as from 0.03mM concentrations absorbed by the plant roots.Keywords: ecotoxicology, metal, contamination.Toxicidade do cádmio na germinação de sementes e no crescimento de Triticum aestivum RESUMO. Esta pesquisa avaliou os efeitos tóxicos do cádmio na germinação e crescimento inicial do trigo (Triticum aestivum, var. IAC-370). Foram avaliados os efeitos ecotoxicológicos de seis concentrações de cádmio (0,03; 0,06; 0,12; 0,6; 1,2; 2,4; 4.8 mM). Os experimentos foram em quadruplicatas, com 25 sementes por replicata, em placas de Petri. As variáveis respostas foram o percentual de germinação, o índice de velocidade de germinação (IVG), o comprimento da parte aérea e da raiz das plântulas, a massa fresca e seca das plântulas. Os resultados reportaram que as sementes de T. aestivum expostas ao cádmio apresentaram decréscimo do seu percentual germinativo de plântulas normais a partir a concentração de 0,03 mM, com redução de 31% do percentual germinativo e decréscimo de 20% no IVG. O efeito inibitório do cádmio no crescimento inicial das plântulas afetou o crescimento das raízes e da parte aérea a partir da concentração 0,12 mM, causando a redução da produção de massa fresca e seca das plântulas a partir de 0,06 mM. A presença e acumulação do cádmio, no solo de cultivo da T. aestivum, poderá causar perdas de produtividades e/ou viabilidade provocadas pela sua toxicidade a partir de concentrações de 0,03 mM que estejam absorvidos pela raiz da planta.Palavras-chave: ecotoxicologia, metal, contaminação.

Phyto-toxic Effect of Heavy Metal (CdCl2) on Seed Germination, Seedling Growth and Antioxidant Defence Metabolism in Wheat (Triticum aestivum L.) Variety HUW-234

“…(Table 3). The above result is well correlated with the finding of (Guilherme et al, 2015). Seed germination and seedling growth inhibition by heavy metals has also been reported by (Siddiqui et al, 2014;Howladar, 2014).…”

Heavy metal induced stress on wheat: phytotoxicity and microbiological management

“…156 As a result, the oxidation of membrane proteins and lipids is usually disrupted, which results in cell death. 157 In a similar study, ref. 158 evaluated the toxicity of six experimental concentrations (0.03; 0.06; 0.12; 0.6; 1.2; 2.4; 4.8 mM) of Cd on seed germination and seedling growth (index of velocity of germination (IVG), length of aerial section and root of seedlings (green and dry mass of the seedlings) of wheat.…”

“…65,66 An immediate effect of the high concentration of metal results in root growth inhibition, which may be shorter, very ramified and without a solid structure. 67,68 The inhibition of root elongation is accompanied by alteration in the architecture and morphology of roots. For instance, many heavy metals, including Pb and Cr, have been reported to rapidly inhibit the root growth, leading to biomass reduction of wheat, 65 probably due to the inhibition of cell division in the root tip.…”

Cadmium toxicity on seed germination and initial growth of chia

“…Acta Scientiarum. Biological Sciences, v. 41, e42174, 2019 On the other hand, Guilherme et al (2015) observed that wheat seeds exposed to Cd exhibited a decrease in percentage of normal plants starting at a concentration of 0.03 mM compared to the experimental control. During initial seedling growth, concentrations of 0.06 mM and 0.12 mM inhibited root and stem growth, respectively, which reduced the dry mass of the seedlings.…”

“…The main symptoms of toxicity are the following: inhibition of seed germination; disturbance of plant metabolic activities; reduction in the root system and stem; changes in the structure of chloroplasts; inhibition of photosynthesis; reduction of plant biomass; lipid peroxidation; decrease in respiration rate and growth; inhibition of the action of enzymes; reduction in cell division; and interference in cellular membrane permeability, which reduces the ability to absorb and transport water and essential elements (e.g., Ca, Mg and K) inside the plant, reducing tolerance to stress (Kabata-Pendias, 2010;Rahoui, Chaoui, & El Ferjani, 2010;Gill, Hasanuzzaman, Nahar, Macovei, & Tuteja, 2013;Chen et al, 2014). Studies of plant development under different Cd contamination levels have been conducted with the common bean (Santos, Fagan, Teixeira, Soares, Reis, & Corrêia, 2013), Jatropha curcas (Chaves & Souza, 2014), wheat (Ahmad, Akhtar, Zahir, & Jamil, 2012;Guilherme, Oliveira, & Silva, 2015), leaf mustard -Brassica juncea (Augusto et al, 2014;Alfiya & Dheera, 2015), crambe (Hu et al, 2015), Brachiaria brizantha and B. decumbens (Borges, D'avila, Campos, Coelho, Miquelluti, & Galvan, 2016), wheat and beans (El Rasafi, Nouri, Bouda, & Haddioui, 2016), chickpeas (Ahmad, Abdel-Latef, Abd-Allah, Hashem, Sarwat, Anjum, & Gucel, 2016), and basil -Ocimum basilicum - (Gharebaghi, Haghighi, & Arouiee, 2017), among others. However, no studies were found that evaluated the toxic effects of Cd on the seed germination of chia.…”