Silicon Fertigation Regimes Attenuates Cadmium Toxicity and Phytoremediation Potential in Two Maize (Zea mays L.) Cultivars by Minimizing Its Uptake and Oxidative Stress

Abstract

Silicon (Si) is an important plant-derived metabolite that is significantly involved in maintaining the stability of a plant’s metabiological, structural and physiological characteristics under the abiotic stressed environment. We conducted the present study using maize (Zea mays L.) cultivars (Sadaf and EV-20) grown in sand artificially contaminated with cadmium (500 µM) in Hoagland’s nutrient solution to investigate its efficiency. Results from the present study evidenced that the toxic concentration of Cd in sand significantly reduced shoot length, root length, shoot fresh weight, root fresh weight, shoot dry weight and root dry weight by 88, 94, 89, 86 99 and 99%, respectively, in Sadaf while decreasing by 98, 97, 93, 99, 84 and 91%, respectively, in EV-20. Similarly, Cd toxicity decreased total chlorophyll and carotenoid content in both varieties of Z. mays. Moreover, the activities of various antioxidants (superoxidase dismutase, peroxidase and catalase) increased under the toxic concentration of Cd in sand which was manifested by the presence of membrane permeability, malondialdehyde (MDA), and hydrogen peroxide (H2O2). Results additionally showed that the toxic effect of Cd was more severe in EV-20 compared with Sadaf under the same conditions of environmental stresses. In addition, the increased concentration of Cd in sand induced a significantly increased Cd accumulation in the roots (141 and 169 mg kg−1 in Sadaf and EV-20, respectively), and shoots (101 and 141 mg kg−1 in Sadaf and EV-20, respectively), while; EV-20 accumulated higher amounts of Cd than Sadaf, with the values for both bioaccumulation factor (BAF) and translocation factor (TF) among all treatments being less than 1. The subsequent negative results of Cd injury can be overcome by the foliar application of Si which not only increased plant growth and biomass, but also decreased oxidative damage induced by the higher concentrations of MDA and H2O2 under a Cd-stressed environment. Moreover, external application of Si decreased the concentration of Cd in the roots and shoots of plants, therefore suggesting that the application of Si can ameliorate Cd toxicity in Z. mays cultivars and results in improved plant growth and composition under Cd stress by minimizing oxidative damage to membrane-bound organelles.

Genome-Wide Characterization and Phylogenetic Analysis of GSK Genes in Maize and Elucidation of Their General Role in Interaction with BZR1

“…In contrast, little is known about whether the GSK-3 family could interact with BZR1 to participate in the BR signaling pathway in maize. Maize is the main cereal grain crop that contributes to solving the food security problem, and it is also known to be a social security concern for farmers [ 26 , 27 , 28 , 29 ]. Thus, understanding the GSK-3 family is significant.…”

Biochar: A promising soil amendment to mitigate heavy metals toxicity in plants

“…Exposure to HMs (Cr) also reduces the chlorophyll contents, starch contents and protein contents (Rath et al, 2019), conversely, HMs induced a significant increase in the accumulation of soluble sugars and proline (Song et al, 2020). In another study conducted on kenaf; it was noted that Cu reduced the root and shoot growth by increasing the H2O2, MDA accumulation, and electrolyte leakage (EL), however, these negative effects were reduced by increasing the activities of antioxidant defense system (Saleem et al, 2022). Cowpea plants explored to Fe toxicity also showed an increase in MDA contents and membrane damage (Ifle et al, 2020).…”

Detection of Fusarium verticillioides in maize sold at some markets in Ibadan Metropolis, Nigeria

“…Maize (Zea mays L.) is a grain crop that is planted worldwide because of its high yields per hectare, ease of cultivation, resilience to a variety of agro-ecological zones, diverse food applications, and storage properties. It is a major part of the diet of millions of people in African countries (Saleem et al, 2022). However, this grain can be susceptible to spoilage organisms.…”