Vegetos
(An International Journal of Plant Research & Biotechnology)
Sclerophylly, water relations, and photosynthetic pigment responses of Cucurbita pepo seedlings to cadmium and copper stress
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Research Articles | Published: 18 August, 2025
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Keywords: Cadmium, Copper, Phytotoxicity, Morpho-physiological responses, Seedlings, Courgette
Abstract
Heavy metal contamination of agricultural soils poses serious ecological risks, with cadmium (Cd) and copper (Cu) being particularly toxic to plants. This study investigated the physiological responses of Cucurbita pepo L. seedlings to Cd and Cu stress (0, 200, and 400 μM for 12 days). Three key findings emerged: (1) Sclerophylly indices—tissue density (D) and specific leaf weight (SLW)—increased under metal stress (e.g., D rose by 11% at 400 μM Cu), whereas specific leaf area (SLA) decreased under Cd but showed variable responses to Cu; (2) Water relations maintained stable relative water content (RWC) despite significant succulence reduction (S: − 13.85% at 200 μM Cu); (3) Photosynthetic pigments exhibited severe chlorophyll b loss (− 52.29% at 400 μM Cd) but stimulated carotenoid production (+ 37.64% at 200 μM Cd), indicating antioxidant activation. These metal-specific responses (Cd disrupting photosynthesis versus Cu affecting cellular hydration) provide critical insights for developing heavy metal-tolerant crops in contaminated environments.
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Author Information
Department of Biology, Faculty of Nature and Life Sciences, University of El Oued, El Oued, Algeria