Cesium Accumulation Patterns and Stress Response in Hydroponic Radish (Raphanus sativus L.): A...

Area of Science:

• Plant Physiology
• Environmental Science
• Biochemistry

Background:

• Cesium (Cs) is a radiotoxic element posing environmental risks.
• Understanding plant responses to Cs is crucial for phytoremediation.
• Radish (Raphanus sativus L.) is a potential candidate for Cs phytoremediation.

Purpose of the Study:

• To investigate Cs enrichment characteristics in radish seedlings.
• To analyze physiological and biochemical responses to Cs exposure.
• To explore molecular mechanisms underlying Cs stress using transcriptome analysis.

Main Methods:

• Hydroponic cultivation of radish seedlings.
• Varying Cs concentrations (0.25-2 mM) for exposure experiments.
• Physiological (growth, pigment content), biochemical (antioxidant enzymes, MDA, ROS), and transcriptome analyses.

Main Results:

• Cs accumulated in radish tissues, primarily in cotyledons, with concentration-dependent enrichment.
• Cs stress caused growth inhibition, reduced carotenoid content, and disrupted mineral nutrient homeostasis (K, Na, Mg, Fe).
• Oxidative stress was induced, evidenced by increased SOD, POD, CAT activities, ROS, and MDA levels.
• Transcriptome analysis revealed differential gene expression in mineral transport, antioxidant systems, and carotenoid biosynthesis.

Conclusions:

• Radish exhibits site-specific Cs accumulation and concentration-dependent physiological responses.
• Cs exposure induces oxidative stress, growth inhibition, and alters mineral nutrition and carotenoid biosynthesis.
• Findings provide a foundation for using radish in Cs-contaminated phytoremediation.