Silicon application improved the yield and nutritional quality while reduced cadmium concentration in rice

Area of Science:

• Agricultural Science
• Environmental Science
• Plant Nutrition

Background:

• Silicon (Si) is vital for rice, but its role in mitigating heavy metal stress on yield and quality is unclear.
• Cadmium (Cd) contamination in rice poses a significant food safety risk.
• Understanding Si application methods is crucial for managing Cd uptake in rice.

Purpose of the Study:

• To investigate the effects of different silicon (Si) application methods on grain yield and cadmium (Cd) accumulation in hybrid rice.
• To evaluate Si's impact on Cd uptake, transport, and translocation in rice under varying soil conditions.
• To assess the influence of Si and selenium (Se)-containing Si fertilizer on rice nutritional quality and safety.

Main Methods:

• Field plot experiment conducted on acidic and calcareous purple soils in Chongqing.
• Four treatments: soil-based Si, foliar Si spray, foliar Se-Si spray, and control.
• Analysis of Cd content, Si and Se accumulation, protein content, and grain yield.

Main Results:

• Si applications reduced brown rice Cd by 11.45–51.85% in acidic soil and 26.93–43.77% in calcareous soil.
• Foliar spray treatments were most effective in reducing Cd below the food safety limit (0.2 mg kg⁻¹).
• Si increased rice yield by 17.15–25.45% in calcareous soil; foliar Se-Si fertilizer enhanced nutritional quality (Si, Se, protein) and reduced Cd.

Conclusions:

• Foliar Si application is a highly effective method for reducing Cd accumulation in rice grains.
• Si application can enhance rice yield, particularly in calcareous soils, and improve grain nutritional quality.
• Foliar application of Se-containing Si fertilizer presents a viable strategy for safe and nutritious rice production, minimizing human exposure to Cd.