Phytoremediation Potential of Cynodon dactylon and Cenchrus ciliaris for Nickel‐Contaminated Soils: A Promising Approach for Land Restoration

Increasing exposure of trace metals causes deleterious effects in plants and land fertility; therefore, appropriate monitoring and remediation strategies are crucial to protect the environment. Salt‐tolerant native plants such as Cynodon dactylon (L.) Pers. and Cenchrus ciliaris L. can exhibit optimum resistance against excessive nickel levels, but their physiology remains under‐investigated. In this study, three ecotypes of both species (i.e., Salt Range, Faisalabad, and Pakka Anna) were collected to assess the impact of Ni toxicity at 20, 40, and 60 mg L −1 on their respective physiological, biochemical, and anatomical features. Cynodon dactylon and Cenchrus ciliaris resisted elevated Ni levels by reducing growth which positively correlated with changes in leaf net photosynthesis rate, stomatal conductance, transpiration, and water use efficiency in all ecotypes. Plants treated with Ni increased soluble sugars especially at the 60 mg L −1 Ni treatment, aiding strict stomatal closure. An increase in amino acids in plants growing at 60 mg L −1 Ni suggested the role of nitrogenous compounds in resisting Ni toxicity. Plants treated with Ni enhanced the vascular bundle and mechanical tissue area in the studied grasses. Among the tested ecotypes, those from Faisalabad and Pakka Anna exhibited the greatest nickel resistance compared to Salt Range populations by modulating their physiological, biochemical, and anatomical traits. Cynodon dactylon and Cenchrus ciliaris emerged as promising candidates for phytoremediation and land restoration in nickel‐contaminated soils, contributing to environmental safety and sustainable land use for agricultural purposes.