Gametophytic responses of Pityrogramma calomelanos to Pb(II) stress: potential application in water pollution...

Environmental contamination by heavy metals is a global issue, requiring effective and long-lasting remediation techniques. Pteridophytes are vascular plants that show phytoremediation potential in both gametophytic and sporophytic phases. Pityrogramma calomelanos (L.) of the family Pteridaceae is a fast-growing fern that is used to assess physiological and biochemical responses to short-term lead [Pb(II)] exposure. Pb(II) causes severe developmental, metabolic, and physiological damage in humans, animals, and plants. However, few plant systems mitigate heavy metal content using various modifications. In vitro, cultured gametophytes were exposed to Pb(II) at various concentrations, and effects were monitored for 2 and 24 hrs on uptake, malondialdehyde (MDA), proline, glutathione (GSH), and enzymes superoxide dismutase (SOD), catalase (CAT), and guaiacol peroxidase (GPOX). Gametophytes show Pb (II) uptake of 71.29 ± 1.79 ppm after 2 hrs and 94.51 ± 2.08 ppm after 24 hrs of a 1000 ppm treatment. Initial Pb(II) uptake increases catalase activity within 2 hrs. At 24 hrs, reactive oxygen species (ROS) increases antioxidant defenses, including SOD, GPOX, GSH, and proline. MDA levels also increase, reflecting ROS-induced lipid peroxidation and oxidative stress. Further study can explore this system in phytoremediation techniques for environments affected by heavy metals and concentrate on molecular mechanisms.