Mudassar Saba, Ahmed Shakil, Sardar Rehana, Yasin Nasim Ahmad, Jabbar Muhammad, Lackner Maximilian
Institute of Botany, University of the Punjab, Lahore 54590, Pakistan.
Department of Biological and Environmental Sciences, Emerson University, Multan 60000, Pakistan.
Toxics. 2024 Dec 14;12(12):911. doi: 10.3390/toxics12120911.
Cadmium (Cd) is one of the foremost phytotoxic elements. Its proportion in agricultural soil is increasing critically due to anthropogenic activities. Cd stress is a major crop production threat affecting food security globally. Triacontanol (TRIA) is a phytohormone that promotes growth, development, and metabolic processes in plants. The current study explicates the mitigation of Cd toxicity in L. (mung bean) seedlings through the application of TRIA by a seed priming technique under Cd stress. The role of TRIA in improving metabolic processes to promote (mung bean, green gram) vegetative growth and performance under both stressed and unstressed conditions was examined during this study. To accomplish this, three doses of TRIA (10, 20, and 30 µmol L) were used to pretreat seeds before they were allowed to grow for 40 days in soil contaminated with 20 mg kg Cd. Cd stress lowered seed germination, morphological growth, and biomass in plants. The maximum root and shoot lengths, fresh and dry weights of roots, and shoot and seed germination rates were recorded for TRIA2 compared with those of TRIA1 and TRIA3 under Cd stress. In Cd-stressed plants, TRIA2 increased the content of chlorophyll (2.1-fold) and (3.1-fold), carotenoid (4.3-fold), total chlorophyll (3.1-fold), and gas exchange attributes, such as the photosynthetic rate (2.9-fold), stomatal conductance (6.0-fold), and transpiration rate (3.5-fold), compared with those in plants treated with only Cd. TRIA seed priming increased nutrient uptake (K, Na, Mg, and Zn), total phenolic content, total soluble protein content, and DPPH (2,2-diphenyl-1-picrylhydrazyl) activity. Additionally, TRIA2 significantly reduced the quantity of Cd in the plants (3.0-fold) and increased the metal tolerance index (6.6-fold) in plants contrasted with those in the Cd-treated plants. However, TRIA2 promoted plant growth and biomass production by lowering Cd-induced stress through modifying the plant antioxidant machinery and reducing oxidative stress. The improved yield characteristics of seedlings treated with TRIA suggest that exogenous TRIA may be used to increase plant tolerance to Cd stress.
镉（Cd）是最重要的植物毒性元素之一。由于人为活动，其在农业土壤中的比例正急剧增加。镉胁迫是影响全球粮食安全的主要作物生产威胁。三十烷醇（TRIA）是一种植物激素，可促进植物的生长、发育和代谢过程。当前研究阐述了在镉胁迫下通过种子引发技术施用三十烷醇来减轻绿豆幼苗中镉的毒性。本研究考察了三十烷醇在改善代谢过程以促进绿豆在胁迫和非胁迫条件下营养生长及表现方面的作用。为此，在让种子于含20 mg/kg镉的污染土壤中生长40天之前，使用三种剂量的三十烷醇（10、20和30 µmol/L）对绿豆种子进行预处理。镉胁迫降低了绿豆植株的种子萌发、形态生长和生物量。与镉胁迫下的TRIA1和TRIA3相比，TRIA2处理的植株记录到最大的根和茎长度、根的鲜重和干重、茎以及种子萌发率。在镉胁迫的绿豆植株中，与仅用镉处理的植株相比，TRIA2使叶绿素a（2.1倍）、叶绿素b（3.1倍）、类胡萝卜素（4.3倍）、总叶绿素（3.1倍）的含量以及气体交换属性如光合速率（2.9倍）、气孔导度（6.0倍）和蒸腾速率（3.5倍）增加。三十烷醇种子引发提高了养分吸收（钾、钠、镁和锌）、总酚含量、总可溶性蛋白含量以及DPPH（2,2 - 二苯基 - 1 - 苦基肼）活性。此外，与镉处理的植株相比，TRIA2显著降低了植株中镉的含量（3.0倍）并提高了植株的金属耐受指数（6.6倍）。然而，TRIA2通过改变植物抗氧化机制并降低氧化应激来减轻镉诱导的胁迫，从而促进植物生长和生物量生产。用三十烷醇处理的绿豆幼苗改善的产量特性表明，外源三十烷醇可用于提高植物对镉胁迫的耐受性。
