Silicon Combined with Melatonin Reduces Cd Absorption and Translocation in Maize

Area of Science:

• Agricultural Science
• Environmental Science
• Plant Physiology

Background:

• Cadmium (Cd) is a toxic heavy metal pollutant impacting crop production and food safety.
• Corn is vulnerable to Cd stress, necessitating strategies to mitigate its adverse effects.
• Silicon and melatonin individually reduce Cd accumulation, but their combined effect is unexplored.

Purpose of the Study:

• To investigate the synergistic effects of silicon and melatonin on mitigating cadmium stress in maize.
• To assess the impact of combined silicon and melatonin treatment on maize growth, physiology, and Cd accumulation.

Main Methods:

• Pot experiments were conducted using maize seedlings under cadmium stress.
• Treatments included control, cadmium stress, cadmium + silicon, cadmium + melatonin, and cadmium + silicon + melatonin.
• Evaluated plant growth parameters, physiological indicators (oxidative damage, antioxidant enzymes, chlorophyll), and cadmium accumulation.

Main Results:

• Cadmium stress significantly inhibited maize growth and induced oxidative damage.
• Combined silicon and melatonin treatment significantly improved plant height, stem diameter, and root parameters compared to single treatments.
• This combination reduced malondialdehyde content and electrolyte leakage while increasing antioxidant enzyme activity, soluble protein, and chlorophyll content.
• Cadmium accumulation in plant tissues and the health risk index were substantially reduced by the combined treatment.

Conclusions:

• Melatonin and silicon exhibit a significant synergistic effect in alleviating cadmium toxicity and reducing cadmium uptake in maize.
• Combined application offers a promising strategy for sustainable and safe corn production in cadmium-contaminated environments.