Hussain Md Tanveer, Haque Md Sabibul, Rabbi Md Fazle, Tasnim Hafsa, Haque Md Asiful, Saha Arnab, Sarwar Akm Golam, Uddin Md Nesar, Hossain Md Alamgir
Department of Crop Botany, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh.
Department of Seed Science and Technology, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh.
PLoS One. 2025 Aug 1;20(8):e0329373. doi: 10.1371/journal.pone.0329373. eCollection 2025.
The hazardous Cadmium (Cd) contamination in vegetables from anthropogenic Cd-abundant agroecosystems is a decisive threat to plants and human health. This study examined the prospective roles of salicylic acid (SA) and methyl jasmonate (MeJA) in alleviating Cd-induced toxic effects in green amaranth plants. The seeds of green amaranth (cv. Ghretokanchan) plant were primed with SA (100 and 250 µM) and MeJA (2.5 and 5 µM) and 21-d-old seedlings were set in six conditions under a hydroponic system: (i) Control, (ii) Cd (10 µM CdCl2·H2O), (iii) Cd with 100 µM SA, (iv) Cd with 250 µM SA, (v) Cd with 2.5 µM MeJA, and (vi) Cd with 5.0 µM MeJA. The experiment was set in a completely randomized design having three replications. Cd exposure for three weeks markedly impaired plant growth, pigment contents, leaf gas exchange, and photosystem-II efficiency; increased malondialdehyde (MDA) and hydrogen peroxide (H2O2) levels indicating induced oxidative stress; and enhanced the activities of superoxide dismutase, guaiacol peroxidase and catalase enzymes. However, seed priming and supplementation of SA and MeJA significantly remediated these Cd-mediated adverse effects. Compared to Cd-alone treatment, 100 and 5 µM of SA and MeJA considerably improved total dry weight by 45% and 94%, respectively whereas leaf MDA and H2O2 levels were substantially reduced by 100 µM SA (37% and 14%) and 5 µM MeJA (35% and 21%). An extensive activity of antioxidants and considerable reduction in Cd uptake and translocation from medium-root-shoot was apparent due to the supplementation of SA and MeJA. The study effectively optimized the levels of SA and MeJA for the improvement of Cd tolerance based on metal uptake, morpho-physiology, and redox regulation, and concludes that either 100 µM SA or 5 µM MeJA could be used for the alleviation of Cd-toxicity in green amaranth plants in Cd-contaminated soils through further field trials.
来自人为镉含量丰富的农业生态系统的蔬菜中存在的有害镉（Cd）污染，对植物和人类健康构成了决定性威胁。本研究考察了水杨酸（SA）和茉莉酸甲酯（MeJA）在减轻镉对苋菜植物毒性影响方面的潜在作用。用SA（100和250 μM）和MeJA（2.5和5 μM）对苋菜（品种Ghretokanchan）种子进行引发处理，并将21日龄的幼苗置于水培系统的六种条件下：（i）对照，（ii）镉（10 μM CdCl₂·H₂O），（iii）镉+100 μM SA，（iv）镉+250 μM SA，（v）镉+2.5 μM MeJA，以及（vi）镉+5.0 μM MeJA。实验采用完全随机设计，有三个重复。镉暴露三周显著损害了植物生长、色素含量、叶片气体交换和光系统II效率；增加了丙二醛（MDA）和过氧化氢（H₂O₂）水平，表明诱导了氧化应激；并增强了超氧化物歧化酶、愈创木酚过氧化物酶和过氧化氢酶的活性。然而，种子引发以及SA和MeJA的添加显著缓解了这些镉介导的不利影响。与单独镉处理相比，100 μM和5 μM的SA和MeJA分别使总干重显著提高了45%和94%，而叶片MDA和H₂O₂水平则因100 μM SA（分别降低37%和14%）和5 μM MeJA（分别降低35%和21%）而大幅降低。由于添加了SA和MeJA，抗氧化剂的活性显著增强，镉从培养基到根再到地上部的吸收和转运也大幅减少。该研究基于金属吸收、形态生理学和氧化还原调节，有效地优化了SA和MeJA的水平以提高镉耐受性，并得出结论，通过进一步的田间试验，100 μM SA或5 μM MeJA均可用于减轻镉污染土壤中苋菜植物的镉毒性。
