Foliar Silicon Application at Multiple Growth Stages Can Improve Lodging Resistance, Yield, and Grain Quality in Rice

Area of Science:

• Agricultural Science
• Plant Nutrition
• Agronomy

Background:

• Silicon (Si) is vital for rice (Oryza sativa L.) yield, quality, and lodging resistance.
• Current practices often involve base or foliar application during critical growth stages.
• Optimal timing for foliar silicon application remains a key research question.

Purpose of the Study:

• To determine the optimal spraying period for water-soluble silicon fertilizer to maximize rice yield and lodging resistance.
• To investigate the effects of foliar silicon application at different growth stages on rice agronomic traits.

Main Methods:

• Field experiment using rice cultivars 'Nanjing9108' and 'Nanjing5718'.
• Three foliar silicon application treatments: tillering + elongation (Si1), tillering + elongation + grain-filling (Si2), elongation + grain-filling (Si3).
• Control (CK) received plain water; plain water served as the control (CK).

Main Results:

• Foliar silicon significantly increased rice yields, with the Si2 treatment showing the best performance (4.02-5.70% yield increase).
• Silicon application enhanced lodging resistance by increasing stem wall thickness and reducing basal internode length (5.52-7.79% improvement).
• Nitrogen (N) uptake and N use efficiency were improved, particularly with Si2 treatment, and leaf senescence was delayed.

Conclusions:

• Foliar silicon application, especially during tillering, elongation, and grain-filling stages (Si2), is optimal for enhancing rice yield and lodging resistance.
• This strategy improves plant structural integrity, nutrient uptake, and photosynthetic duration.
• Optimized silicon application timing offers a dual benefit for high-yield and lodging-resistant rice production.