Nanoparticle-based soil amendments improve plant growth, development, and phytostabilization

Nanoparticle-based soil amendments represent a promising strategy to improve plant growth and phytostabilization in contaminated soils. This study investigated the efficacy of nano-sized stilbite-zeolite (NSZ) and nanoblack-carbon (NBC) on durum-wheat (<i>Triticum turgidum</i> L.). This study was conducted to evaluate the effects of NSZ particle size (0.2 mm, 0.1 mm, <0.05 mm), NSZ application rate (0%, 4%, 8% w/w), and NBC application rate (0%, 4%, 8% w/w). The co-application of fine-particle NSZ (<0.05 mm) and NBC, each at 8% (w/w), yielded the most significant improvements. This optimal treatment enhanced soil-health, increasing CEC by 20.04% and available-phosphorus by over 300% compared to the control. Grain yield increased from 1,057 kg ha^-1 in the control to 2,544 kg ha^-1, representing a 140.5% improvement. The number of grains per spike increased from 22.33 to 34.3, while the amendments effectively reduced heavy metal uptake. Specific treatments, such as NSZ at 4% (w/w) (NSZ₂), significantly reduced Cd and Hg concentrations in grain by 69.7% and 69.1%, respectively, compared to the control. The NBC treatment at 8% (w/w) (NBC₂) reduced As and Pb levels by 55.8% and 42.1%. These reductions confirm successful immobilization of metals in the soil and restricted translocation to edible grains.