COMPARATIVE PHYTOTOXIC ASSESSMENT OF SILVER NANOPARTICLES, HUMIC ACID-CAPPED AGNPS, AND CTAB-CAPPED AGNPS ON GERMINATION AND EARLY SEEDLING GROWTH OF DR-16 COARSE RICE (ORYZA SATIVA L) AT DIFFERENT CONCENTRATIONS

Abstract

The increasing application of silver nanoparticles (AgNPs) and its capping agents in agriculture raises concerns about their phytotoxic possessions on harvested plants. This research  evaluated phytotoxic impact of AgNPs, Humic acid induced with synthesized silver nanoparticles, and AgNPs capped with CTAB , on the seedling growth of rice variety DR-16 (coarse) taken from Dokari Agricultural  Research Institute Larkana . Seeds were treated with synthesized AgNPs, Humic acid-AgNPs, CTAB-AgNPs, at 5, 10, 15, and 20 ppm concentrations under controlled laboratory conditions. Growth parameters included   shoot and root length, fresh and dry weight and germination percentage were recorded. Results indicated concentration-dependent respond, where low concentrations (5–10 ppm) showed growth stimulation, while higher concentrations (15–20 ppm) exhibited phytotoxic effects, indicated reduced root elongation and biomass. Capping agents significantly reduced toxicity by stabilizing nanoparticles and lowering reactive oxygen species (ROS) production. The study concluded, controlled use of capped AgNPs enhanced plant growth, whereas higher concentrations induced oxidative stress and phytotoxicity