Document Type : Research Paper - Biotic and Abiotic Stress
Authors
1 Department of Plant Genetics and Production Engineering, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran
2 Ph.D. Student, Department of Horticultural Sciences, Faculty of Agriculture & Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran
Abstract
Introduction: Today, with the industrialization of societies, many toxic compounds have been released into the environment. Environmental pollution caused by heavy metals is one of the most important global factors of soil pollution that threatens food security. Considering that most of Iran's calcareous soils are exposed to the stress of heavy metals and this problem is increasing day by day. Today, researchers are looking for a solution to reduce the toxic effects of heavy metals in the soil and to improve the quality of crops grown in soils contaminated with heavy metals.
Materials and Methods: This experiment was conducted in order to evaluate some biochemical characteristics of fennel plant and the possibility of mitigating the effects of cadmium heavy metal stress by foliar spraying of selenium nanoparticles, algae extract and their interaction in greenhouse conditions in a factorial manner based on a randomized complete block experimental design with three replications in 2023-2024 was implemented. The first factor includes the heavy metal cadmium chloride at two levels (control and 20 mg/kg of soil) and the second factor is foliar feeding at three levels (control, algal extract, and selenium nanoparticle with concentrations of 1 mg/L and 20 mg/L, respectively. In the four-leaf stage, foliar spraying at three zero levels, algae extract (2 mg/liter) and selenium nanoparticle (20 mg/liter) was done three times with a time interval of 15 days, and ten days after the plant was placed under stress For this purpose, sampling of control and treatment samples was done in order to check the biochemical parameters at the end of the physiological stage of the plant.
Results: The findings showed that under cadmium stress, the amount of malondialdehyde, catalase and superoxide dismutase enzymes, proline content and ion leakage percentage increased significantly, while the content of photosynthetic pigments decreased compared to the control. Also, the highest level of malondialdehyde concentration and activity of catalase and superoxide dismutase enzymes were observed in foliar spraying with algal extract under cadmium stress compared to the control. The synergistic effect of selenium nanoparticle and algal extract decreased ion leakage by 3.91% and increased proline and photosynthetic pigments by 16.73%, especially chlorophyll b by 33.11%. In other words, the adverse effects of cadmium stress have been reduced by strengthening the antioxidant and photosynthetic system of fennel plant by selenium nanoparticles and algae extract.Also, the highest level of malondialdehyde concentration and activity of catalase and superoxide dismutase enzymes were observed in foliar spraying with algal extract under cadmium stress compared to the control. The synergistic effect of selenium nanoparticle and algal extract decreased ion leakage by 3.91% and increased proline and photosynthetic pigments by 16.73%, especially chlorophyll b by 33.11%. In other words, the adverse effects of cadmium stress have been reduced by strengthening the antioxidant and photosynthetic system of fennel plant by selenium nanoparticles and algae extract.
Conclusions: In general, foliar feeding with algal extract (concentration of 1 mg/L) due to the high content of macro and micro elements and antioxidant properties compared to selenium nanoparticles, has been able to inhibit free radicals by increasing the activity of antioxidant enzymes and by reducing the electrolyte leakage, maintain the integrity of the membrane in the condition of cadmium stress.
Keywords
Main Subjects
)