Effects of Magnetically Treated Sedum Alfredii Seeds On The Dissolved Organic Matter Characteristics of Cd-Contaminated Soil During Phytoextraction

Abstract

The effects of magnetic field treatments on the two determining factors of phytoremediation, growth status and element uptake capacity, of Sedum alfredii have been thoroughly studied; however, minimal studies have been performed to determine the influence of the Cd hyperaccumulator Sedum alfredii, grown from magnetically treated seeds, on the dissolved organic matter (DOM) characteristics in its rhizosphere. A series of pot experiments were conducted to evaluate the variations in the DOM concentration and fractionations in the rhizosphere of S. alfredii treated with external magnetic fields. Compared with the untreated seeds, S. alfredii grown from magnetically treated seeds excreted more DOM in its rhizosphere. Additionally, the hydrophilic DOM fractionation proportion, which presented a greater capacity to mobilize Cd in the soil, increased from 42.7 % in the control sample to 47.2 % in the 150 mT magnetically treated S. alfredii sample. The water-soluble and exchangeable forms of Cd (extracted using deionized water and NH4NO3, respectively) in the rhizosphere of the magnetically treated S. alfredii were significantly lower than those of the control sample. Furthermore, the Cd extraction capacity of DOM from the rhizosphere of the magnetically treated S. alfredii was greater than that of the control sample, thereby increasing the Cd uptake ability of the magnetically treated species. These results suggest that the secretion of large amounts of DOM, especially acid and hydrophilic fractionations, is an essential mechanism of magnetically treated S. alfredii to mobilize Cd in the soil.

Magnetic field treatment on horticultural and agricultural crops: its benefits and challenges

“…Both magnetopriming and magnetised water (MW) irrigation can enhance the tolerance and vitality of cultivated plants under various environmental stresses (Baghel et al, 2019;Hasan et al, 2020;Hozayn et al, 2021;Kataria et al, 2022Kataria et al, , 2023. It ensures not only the ability of plants to survive under adverse stress conditions, but also the accumulation of heavy metals by plants grown in heavy metal soil; thus, it improves the ability of plants to help in soil restoration (Tang et al, 2022;Prajapati and Patel, 2023). MF treatment research in this direction provides great potential for the use of plants for heavy metal soil remediation.…”

“…pekinensis) (Han et al, 2008), lettuce (Lactuca sativa) (Abdel Latef et al, 2020), radish (Raphanus sativus) (Xia et al, 2020), tomato (Solanum lycopersicum) (Da Silva and Dobránszki, 2016;Souza-Torres et al, 2020), eggplant (Solanum melongena) (Cui et al, 2020;Kishore et al, 2022), sugar beet (Beta vulgaris) (Faiyad and Hozayn, 2020), sunflower (Helianthus annuus) (Afzal et al, 2021;Bukhari et al, 2021), passion fruit (Passiflora edulis) (Menegatti et al, 2019) and cotton (Gossypium spp.) (Da Silva and Dobránszki, 2016), Sedum alfredii (Tang et al, 2022).…”

“…Compared with the control plants, the S. alfredii ones grown from treated seeds excreted more DOM in their rhizosphere. Additionally, the hydrophilic DOM fractionation proportion, which presented greater capacity to mobilise Cd in soil, increased from 42.7% (control) to 47.2% (150 mT MF treatment) (Tang et al, 2022). In the experiment of salinity stress, the maize (Z. mays) plants, grown from the seeds treated with 200 mT static MF for 1 hr, showed lower H 2 O 2 and better photosynthetic performance and bigger yield under all selected salt stress levels (0, 25, 50, 75, 100 mM NaCl concentration) (Baghel et al, 2019).…”