PHYTOCHEMICAL SIGNATURES, ALLELOPATHIC INTERACTIONS, AND METAL STRESS ADAPTATION IN CYMBOPOGON JWARANCUSA AND ARUNDO DONAX: A CROSS-DISCIPLINARY PERSPECTIVE ON PLANT–ANIMAL ECOLOGICAL

Abstract

This study investigated the allelopathic potential, phytochemical composition, heavy metal accumulation, and associated hematological responses of Cymbopogon jwarancusa and Arundo donax. Methanolic extracts of both species were evaluated for their inhibitory effects on radish (Raphanus sativus) seed germination and root growth under varying concentrations (10-10,000 ppm). A strong dose-dependent allelopathic effect was observed, with maximum root inhibition reaching 65.61% in C. jwarancusa and 68.25% in A. donax at the highest concentration. Germination index decreased significantly (p < 0.001), indicating pronounced phytotoxicity. Phytochemical analysis revealed significantly higher concentrations of phenols (4.69 ± 0.02), flavonoids (4.12 ± 0.04), and saponins (3.21 ± 0.02) in C. jwarancusa compared to A. donax, suggesting enhanced bioactivity and stress tolerance. Heavy metal analysis demonstrated that C. jwarancusa exhibited higher uptake and bioaccumulation factors (BAF > 1) for several metals, particularly Cu, Cr, and Ni, along with translocation factors (TF ≈ 1), indicating efficient metal transfer to aerial parts. In contrast, A. donax showed lower BAF and TF (<1), reflecting restricted translocation and root-level metal retention. Hematological parameters in buffaloes varied significantly (p < 0.001) across seasons, with RBC counts ranging from 5.15 × 10¹²/L to 7.21 × 10¹²/L, indicating adaptive physiological responses to environmental and biochemical stressors. The results demonstrate that C. jwarancusa demonstrated strong potential as a phytoextractor, whereas A. donax functioned effectively as a phytostabilizer. The study highlights the dual role of these species in phytoremediation and allelopathic weed control, supporting their application in sustainable environmental management