Alleviation of Cadmium Stress by Silicon Supplementation in Peas by the Modulation of Morpho-Physio-Biochemical Variables and Health Risk Assessment

Abstract

Agricultural soil quality degradation by potentially toxic elements, specifically cadmium (Cd), poses a significant threat to plant growth and the health of humans. However, the supplementation of various salts of silicon (Si) to mitigate the adverse effect of Cd on the productivity of peas (Pisum sativum L.) is less known. Therefore, the present investigation was designed to evaluate the exogenous application at various levels (0, 0.50, 1.00 and 1.50 mM) of silicate compounds (sodium and potassium silicates) on pea growth, gaseous exchange, antioxidant enzyme activities and the potential health risk of Cd stress (20 mg kg−1 of soil) using CdCl2. The findings of the study showed that Cd stress significantly reduced growth, the fresh and dry biomass of roots and shoots and chlorophyll content. In addition, electrolyte leakage, antioxidant enzymes and the content of Cd in plant tissues were enhanced in Cd-induced stressed plants. An application of Si enhanced the development of stressed plants by modulating the growth of fresh and dry biomass, improving the chlorophyll contents and decreasing leakage from the plasma membrane. Furthermore, Si addition performed a vital function in relieving the effects of Cd stress by stimulating antioxidant potential. Hence, a significant level of metal protection was achieved by 1.00 mM of potassium silicate application under the Cd levels related to stress conditions, pointing to the fact that the Si concentration required for plant growth under Cd stress surpassed that which was required for general growth, enzymatic antioxidants regulation and limiting toxic metal uptake in plant tissues under normal conditions. The findings of this research work provide a feasible approach to reduce Cd toxicity in peas and to manage the entry and accumulation of Cd in food crops.

Silicon’s Influence on Polyphenol and Flavonoid Profiles in Pea (Pisum sativum L.) under Cadmium Exposure in Hydroponics: A Study of Metabolomics, Extraction Efficacy, and Antimicrobial Properties of Extracts

“…Galal et al (2021) investigated the accumulation potential of heavy metals in various organs of field pea and observed significant reductions in fresh and dry weights of pea plants, as well as pod production, in polluted (20.4 mg Cd/kg soil) solis compared to nonpolluted (0.2 mg Cd/kg soil) ones. Furthermore, Batool et al (2022) found that Cd pollution significantly decreased traits related to growth, phenology, and biomass of pea plants, while also markedly increasing Cd contents in roots, shoots, and seeds compared to the control. Additionally, Cd contamination has been shown to highly affect the biomass and productivity of Solanum lycopersicum L. plants grown in soil irrigated with untreated industrial wastewater …”

“…19−21 Indirect evidence from global data indicates that legumes accumulate Cd within the range of 0.08−0.28 mg/kg fruit/ seed dry weight, surpassing the maximum permissible values recommended by FAO/WHO for heavy metals in vegetables (<0.02 mg Cd/kg DW). 22,23 Several studies, including those by Galal et al (2021), 24 Batool et al (2022), 25 and others, 26−29 have illustrated the detrimental effects of Cd contamination on growth and yield parameters of pea cultivars, along with other pulses like pigeonpea, 30 as well as globally significant crops such as wheat 31 and tomatoes. 32 Galal et al ( 2021) 24 investigated the accumulation potential of heavy metals in various organs of field pea and observed significant reductions in fresh and dry weights of pea plants, as well as pod production, in polluted (20.4 mg Cd/kg soil) solis compared to nonpolluted (0.2 mg Cd/kg soil) ones.…”

“…This suggests that legumes possess the ability to increase bioaccumulation and available Cd content in neighboring crops. 35 Pea plants exposed to high levels of Cd in soil often exhibit growth suppression and stunted development, 24,25,36,37 with symptoms like chlorosis in leaves indicating disruptions in chlorophyll production and photosynthetic activity. 38 Cd interferes with various metabolic processes, leading to nutrient deficiencies and imbalances, further compromising plant health and productivity.…”

“…Pea plants exposed to high levels of Cd in soil often exhibit growth suppression and stunted development, ,,, with symptoms like chlorosis in leaves indicating disruptions in chlorophyll production and photosynthetic activity . Cd interferes with various metabolic processes, leading to nutrient deficiencies and imbalances, further compromising plant health and productivity. ,,, Additionally, Cd accumulation in pea crops can impact the concentration of bioactive compounds in harvested seeds, such as antioxidants and phytochemicals, thereby reducing the nutritional quality of the harvested peas.…”

Foliar Application of Ethylenediamine Tetraacetic Acid (EDTA) Improves the Growth and Yield of Brown Mustard (Brassica juncea) by Modulating Photosynthetic Pigments, Antioxidant Defense, and Osmolyte Production under Lead (Pb) Stress

“…Heavy metals are non-biodegradable trace elements and are considered harmful to plants, animals, and humans [ 1 ]. Some heavy metals are categorized as essential heavy metals, which are somehow required for plant growth [ 2 ], while others are classified as non-essential heavy metals, which are not required for plant growth [ 3 , 4 ].…”