Mitigating lead-induced stress and DNA damage in wheat plant using palm seed-based bio-adsorbent

Heavy metals (HMs) are metalloids that exhibit biological toxicity to plants. Effective management of HM-contaminated environments is crucial for sustainable plant development. Palm seeds, as agricultural residues with nutritional value, show potential for bioremediation applications. This study aims to evaluate the efficacy of air-dried (D) and roasted (R) palm seed powder (PSP) as HMs adsorbents. PSP was used to mitigate lead (Pb) toxicity in wheat and reduce its bioavailability in contaminated soils. PSP contains 33% fibers and 23% carbohydrates, and other constituents. PSP could adsorb cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), and zinc (Zn) at 5, 50, and 500 mg L^-1 of each HMs. Pb adsorption rates reached a maximum of 93% at 500 mg L^-1. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR) analysis confirmed the porous nature and the presence of active functional groups such as O-H, C-H, and C═O. D and R powders in soil improved the growth parameters under Pb stress by enhancing the production of antioxidant compounds, soluble carbohydrates, protein, and proline. The frequency of damaged nuclei was reduced by PSP treatments in wheat, which in turn reduced Pb-induced DNA damage. When compared to untreated plants, the DNA damage was reduced by 26.63% and 64.95% when D and R PSP were used at 500 mg L^-1 Pb, respectively. At 50 mg L^-1 Pb, shoots accumulated more Pb than roots (TF = 1.97), while at 500 mg L^-1, roots accumulated more (TF = 0.57), reducing the tolerance index (TI) to 50.97. Palm seed powder treatments lowered Pb uptake and increased the TI to 90.61 in 50 mg L^-1 Pb D PSP-amended soil. In conclusion, PSPs possess the potential to be an efficient bio-adsorbent of different HMs that could be implemented to sustain plant growth in HMs-contaminated environments.