Abstract
The present study was conducted to evaluate the impact of Cu-induced toxicity on the growth, yield parameters, and Cu accumulation in the seeds of black cumin (Nigella sativa L.) plants. In this experiment, plants grown in earthen pots filled with 3 kg of garden soil were contaminated with different dilutions (1.5, 2.0, 2.5, 3.0, 3.5, 4.0) of Cu in millimoles (mM), except for the control. Growth, yield, and Cu bioaccumulation parameters were recorded and analyzed at the harvesting stage. Results revealed that all doses of Cu show a considerable negative effect on the growth and yield parameters of black cumin as the concentration of Cu increased in the soil and reduced all of the growth parameters significantly (p ≤ 0.05). With each Cu dose, the levels of chlorophyll a and b in the tissues of fresh leaves decreased significantly (p ≤ 0.05). Fruit and seed yield also decreased significantly (p ≤ 0.05) from the lower to the higher dose of Cu (1.5 mM to 4.0 mM). Cu bioaccumulation levels in the seeds of all treated plants (Control to 4.0 mM Cu) are under the threshold limit for Cu set by the Food Safety and Standards Authority of India (FSSAI) and World Health Organization (WHO) for spices and are safe for human consumption. Finally, due to the low seed yield in Cu-contaminated soil, it is advised to farmers that Nigella sativa should not be grown in Cu-contaminated soil to avoid economic loss.
Graphical Abstract
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Acknowledgments
The authors would like to express their gratitude to the Chairperson of the Botany Department of Aligarh Muslim University (A.M.U.), Aligarh for providing research experiment facilities and technical assistance with sample analysis.
Disclosure statement
No potential conflict of interest was reported by the authors.
Authors’ contributions
Adnan Khan: Conceptualization, experiment methodology, writing, estimation and preparation of original data; Athar Ali Khan: Supervision, drafting, reviewing and editing in manuscript; Syed Aiman Hasan: Statistical analysis of data; Mohd Irfan: Prepare graphical abstract; Mohd Ahmad: Table and graph preparation.
Consent for publication
All authors agreed and gave their consent to publish this article.
Novelty statement
This manuscript evaluates the impact of different concentrations of Cu on the growth and seed output of black cumin plants and the bioaccumulation of Cu in their seeds as well as evaluates the risk posed to human health by using Cu-contaminated seeds of black cumin.