Abstract
Modifying biochar with nano-nutrients is one of the most effective methods in improving the efficiency of biochar in reducing the adverse effects of environmental stresses such as salinity on plant growth and productivity. The possible effects of solid biochar, nano-silicon dioxide enriched biochar, nano-calcium carbonate enriched biochar, and combined application of these enriched biochars on physiological performance of safflower (Carthamus tinctorius L.) were evaluated under different levels of salt stress (non-saline, 6 and 12 dSm−1). Salt stress increased sodium content, reactive oxygen species generation, and antioxidant enzymes activity, but decreased potassium, calcium, magnesium, iron, zinc, silicon, photosynthetic pigments, leaf water content, and seed yield (by about 36%) of safflower plants. The addition of biochar forms to the saline soil improved growth (up to 24.6%) and seed yield (up to 37%) of safflower by reducing sodium accumulation (by about 32%) and ROS generation and enhancing nutrient uptake, photosynthetic pigments, and water contents of leaves. The combined forms of enriched biochars were the best treatment on reducing salt stress effects on safflower plants. Therefore, application of enriched biochars has a high potential to reduce the harmful effects of salt stress on plants.
Novelty statement
Enriching biochar with calcium and silicon nanoparticles is a practical method to improve the ability of biochar to adsorb and immobilize harmful elements such as sodium in the rhizosphere. This enrichment enhanced safflower plant growth and physiological efficiency under salt stress by reducing sodium absorption and increasing the availability of beneficial nutrients.
Acknowledgments
We appreciate the University of Tabriz for the support of this work.
Author contributions
Kazem Ghassemi-Golezani: supervision, experimental design, and final editing. Seyyed Amirreza Mousavi: experimental work, data analysis, and initial writing. Salar Farhangi-Abriz: experimental help and initial editing.
Disclosure statement
The authors have no relevant financial or non-financial interests to disclose.
Ethical approval
Not applicable.
Consent form
Not applicable.
Data availability statement
The necessary information is available from the corresponding author on reasonable request.