Univrsity of Tehran Press Iranian Journal of Field Crop Science 2008-4811 55 3 2024 09 22 Photosynthetic and biochemical response of Kochia (Bassia scoparia L.) seedlings to cadmium and polyvinyl chloride microplastics stresses Photosynthetic and biochemical response of Kochia (Bassia scoparia L.) seedlings to cadmium and polyvinyl chloride microplastics stresses 149 160 99288 10.22059/ijfcs.2024.370559.655055 FA Ali Sepehri Department of Plant Production and Genetics,, Faculty of Agriculture,, Bu-Ali Sina University, Hamedan,, Iran Atefeh Mirzaei Department of Plant Production and Genetics, Faculty of Agriculture,, Bu-Ali Sina University, Hamedan,, Iran Journal Article 2024 01 07 Contamination of agricultural soils with microplastics and cadmium as an important environmental issue is causing oxidative stress in plants. In this research, the physiological and biochemical reactions of Kochia (Bassia scoparia L.) seedlings under the above stresses. The factorial experiment was conducted in the form of a completely randomized design in three replications, in the Faculty of Agriculture, Bu Ali Sina University in 2022. Polyvinyl chloride (PVC) microplastics were used at three levels of 0, 0.1 and 1 percent by weight of soil and cadmium (CdCl2) at two levels of 0 and 10 mg/kg of soil. The results of this research showed that by increasing the amount of cadmium to 10 mg in the presence of 0, 0.1 and 1 percent of microplastics, the amount of total chlorophyll decreased, which caused a decrease in the rate of net photosynthesis and transpiration of Kochia seedlings and as a result decreased the total dry weight of the plant. Microplastic and cadmium stress increased ion leakage, malondialdehyde content and hydrogen peroxide activity. In plants exposed to the simultaneous stress of microplastics and cadmium, total phenol increased compared to the control (without cadmium), so that with the increase of cadmium concentration from zero to 10 mg, the amount of total phenol increased by 40.72 per cent. In general, soil contamination with polyvinyl chloride microplastics, especially in high amounts increases the availability of the heavy metal cadmium and causes an increase in the intensity of stress in Kochia seedlings. Contamination of agricultural soils with microplastics and cadmium as an important environmental issue is causing oxidative stress in plants. In this research, the physiological and biochemical reactions of Kochia (Bassia scoparia L.) seedlings under the above stresses. The factorial experiment was conducted in the form of a completely randomized design in three replications, in the Faculty of Agriculture, Bu Ali Sina University in 2022. Polyvinyl chloride (PVC) microplastics were used at three levels of 0, 0.1 and 1 percent by weight of soil and cadmium (CdCl2) at two levels of 0 and 10 mg/kg of soil. The results of this research showed that by increasing the amount of cadmium to 10 mg in the presence of 0, 0.1 and 1 percent of microplastics, the amount of total chlorophyll decreased, which caused a decrease in the rate of net photosynthesis and transpiration of Kochia seedlings and as a result decreased the total dry weight of the plant. Microplastic and cadmium stress increased ion leakage, malondialdehyde content and hydrogen peroxide activity. In plants exposed to the simultaneous stress of microplastics and cadmium, total phenol increased compared to the control (without cadmium), so that with the increase of cadmium concentration from zero to 10 mg, the amount of total phenol increased by 40.72 per cent. In general, soil contamination with polyvinyl chloride microplastics, especially in high amounts increases the availability of the heavy metal cadmium and causes an increase in the intensity of stress in Kochia seedlings. https://ijfcs.ut.ac.ir/article_99288_9e8b8a05b3b2c9431f3dec04c304c8b6.pdf