Phosphorus-Induced Adaptation Mechanisms of Rye Grown on Post-Flotation Copper Tailings

Area of Science:

• Environmental Science
• Plant Science
• Soil Science

Background:

• Phytotechnologies offer cost-effective solutions for managing contaminated lands, but revegetating mine tailings remains challenging.
• Copper (Cu) ore processing generates tailings that require effective remediation strategies for successful land reclamation.

Purpose of the Study:

• To evaluate the growth and survival potential of rye (Secale cereale L.) on post-flotation copper mine tailings.
• To investigate the impact of phosphorus (P) availability and copper (Cu) concentrations on rye performance in tailings.

Main Methods:

• A pot experiment was conducted using four rye varieties grown on copper tailings with varying phosphorus doses.
• Plant growth, dry mass, Cu and P uptake, and physiological parameters related to P mobilization were assessed.
• Mechanisms of plant tolerance, including root proton efflux and organic acid exudation, were analyzed.

Main Results:

• Rye varieties exhibited tolerance to high copper concentrations, with intracellular Cu levels below toxic thresholds.
• Low phosphorus availability, due to alkaline tailings, was the primary factor limiting rye growth and tolerance.
• Efficient photosynthetic activity correlated with enhanced phosphorus mobilization capacity in rye plants.

Conclusions:

• Rye demonstrates potential for revegetating copper mine tailings, with phosphorus availability being a critical factor for success.
• Rye genotypes with a more primitive genetic background may be better suited for growth on these challenging substrates.
• Findings provide insights for developing strategies to revitalize degraded lands using phytotechnology.