Effects of silver nanoparticles on the physiology, stress, and mineral uptake of banana cultivars in vitro and greenhouse

<i>In vitro</i> experiments on the Cavendish banana var. Williams, with shoots cultured in media supplemented with AgNPs at concentrations of 0, 25, 50, 100, and 1000 mg L^-1, showed significant reductions in shoot formation, length, chlorophyll content, and leaf number as AgNP concentrations increased. Rooting experiments revealed similar trends with high AgNP concentrations resulting in a decreasing root number and size. Greenhouse experiments on Gros Michel bananas, evaluating AgNP uptake through foliar and drench applications at 0, 25, 50, and 100 mg L^-1, monitored over a month, showed no statistically significant differences in growth parameters between treated plants and controls. However, tissue analysis revealed higher leaf Ag concentrations than roots and stems. The study also analyzed antioxidant gene expression via qPCR, targeting genes such as <i>MaSOD</i> (superoxide dismutase), <i>MaCAT</i> (catalase)<i>, MaAPX</i> (ascorbate peroxidase), and <i>MaGPX</i> (glutathione peroxidase), showing altered profiles in response to AgNP exposure and indicating induced oxidative stress. This research underscores the complex interactions between AgNPs and banana plants, emphasizing the need for further study to optimize safe and effective AgNP application in agriculture, balancing crop protection and environmental safety.