Calcium defeating strategy for metal stress in some submerged hydrophytes growing in aquaponics

Abstract The present work is a fetching trial providing promising insights about calcium. Calcium plays a crucial role in plant nutrition; moreover Calcium ions (Ca2+) show a versatile propensity in plant structure and function. Introducing heavy metals especially Cadmium to plant interrupts many biotic processes which ultimately lead to plant death. Herein, from submerged hydrophytes, Ceratophyllum demersum, Myriophyllum spicatum and Najas marina are examined to evaluate their tolerance against metal stress. All of them are subjected to a mixture containing different doses of cadmium with fixed doses of lead and nickel in hydroponic culture for one week. All of inspected species exhibit analogous response regarding calcium elevation level. The observed positive correlation between Cd and Ca is attributed to invigorating role of calcium in plant resistance. Calcium is incorporated in plant defense strategy to both environmental and hormonal signals. The involvement of calcium in reducing metal uptake particularly Cd influx and translocation, controlling signal transduction and alleviating oxidative damages in plant explains the reasons beyond the transit cytosolic calcium increase in all selected species.