Use of Potassium Fertilization to Ameliorate the Adverse Effects of Saline-sodic Stress Condition (EC_w: SAR_w Levels) in Rice (Oryza Sativa L.)

ABSTRACT

Salt-affected soils expand around the world and become a critical handicap for high crop yield. Saline-sodic soil contributed a major portion in salt-affected soils. Such types of soils have a sizable amount of Na⁺ in nutrient medium and that reduce the K⁺ uptake in plants. A hydroponic experiment was performed to investigate the ameliorative effect of different doses of potassium fertilizer (K₁ = 0.3, K₂ = 0.6 and K₃ = 1.2 mM L⁻¹) on rice (Oryza sativa L.) under different EC_w (6 dS m⁻¹) and SAR_w [12 and 24 (mmol L⁻¹)^1/2] levels. Application of K⁺ at elevated levels under saline-sodic conditions improved the concentration of anti-oxidant enzymes, plant physiological, and biochemical attributes by improving the K⁺: Na⁺ ratio in plant tissues. Total phenolic content, total soluble protein, and soluble sugar content of rice plant were increased with an increase in potassium dose and saline-sodicity. Maximum K⁺: Na⁺ ratios, 4.13 and 2.0 were observed in shoot and root, respectively upon application of K⁺ at 1.2 mM L⁻¹ in a solution having EC_w: SAR_w level of 6: 12. This study suggested that application of potassium at elevated levels (1.2 mM L⁻¹) has enhanced the rice growth by reducing the harmful effect of Na⁺ salts on plant physiology, biochemical attributes, and anti-oxidant enzymes under specific saline-sodic conditions.

KEYWORDS:

• Potassium fertilizer
• salt-affected soil
• hydroponic
• anti-oxidant enzymes
• total phenolic content
• total soluble protein
• soluble sugar content

Supplementary material

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