Evaluation of developmental responses of two crop plants exposed to silver and zinc oxide nanoparticles

摘要: The increasing applications of different nanomaterials in the myriad nano-enabled products and their potential for leaching have raised considerable environmental, health safety (EHS) concerns. As systematic studies investigating anomalies morphology anatomy crop plants are scarce, herein we report on developmental responses two agriculturally significant plants, maize (Zea mays L.) cabbage (Brassica oleracea var. capitata L.), upon vitro exposure to nanoparticles citrate-coated silver (Citrate-nAg) zinc oxide (nZnO). Analyses involve histology primary root using light microscopy, metal biouptake, moisture content, rate germination, elongation. Comparative toxicity profiles ionic salts (AgNO3 ZnSO4) developed. Notably, uncover structural changes cells Citrate-nAg, nZnO, AgNO3, ZnSO4, possibly due suggesting functional impairments plant growth development. Citrate-nAg results lower Ag biouptake compared AgNO3 treatment maize. Microscopic evidence reveals 'tunneling-like effect' with nZnO treatment, while leads cell erosion apical meristem. In maize, a change metaxylem count is evident ZnSO4 but not (p>0.1). both cabbage, measures germination elongation reveal nanoparticle free ions. data do support osmotically-induced water stress hypothesis explaining toxicity, discuss other proximate mechanisms including role hormones transcription factors. These findings highlight previously overlooked, anatomically effects nanoparticles, recommend considering detailed anatomical investigations tandem standard phytotoxicity assays (germination elongation) as latter ones appear less sensitive screening nanomaterial insults.