Endoreduplication changes in five in-vitro-grown crops upon treatment with silver nanoparticles

Abstract

AbstractSilver nanoparticles (AgNPs) are now often utilized in agriculture and horticulture. One of the common applications is to use AgNPs as antimicrobial agents in tissue cultures instead of using standard sterilization procedures. However, in addition to beneficial effects they have also cyto- and genotoxic ones, inducing DNA damage and changing cell cycle dynamics. The aim of this study was to determine the effect of AgNPs at different concentrations (50–100 ppm) on endoreduplication, DNA content, and growth of seedlings of five crops: rapeseed, white mustard, sugar beet, red clover, and alfalfa, cultivated in vitro. Flow cytometry was used to establish genome size and DNA synthesis patterns in the roots, hypocotyls, and leaves of first-leaf-pair seedlings. AgNP-treatment did not influence germination or genome size, but increased root length and endoreduplication intensity. The increases were especially pronounced in species/organs with high polysomaty. We suggest that enhanced endopolyploidization is a defense mechanism against the stress induced by AgNPs causing mitotic division disruption.