Effects of Microplastics on Growth and Physiological Characteristics of Tobacco (Nicotiana tabacum L.)

The environmental effects caused by the proliferation of microplastics have received extensive attention. However, at this stage, there is a lack of research on the toxicology of microplastics and their impacts on plants. This study explored the effects of microplastics on the growth and physiological characteristics of tobacco. Using tobacco (Nicotiana tabacum L.) variety Yunyan87 and low-density polyethylene (LDPE, 13 μm particle size), different concentrations, which were 0 mg/L (CK), 10 mg/L (T1), 100 mg/L (T2), and 1000 mg/L (T3), were subjected to hydroponic experiments to study the effects of microplastics on the growth and physiological characteristics of tobacco. The results showed that microplastics had a certain inhibitory effect on the growth of tobacco. Among them, high concentrations of microplastics significantly inhibited the root architecture and growth characteristics. According to the performance observed with different treatments, the content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) increased in the medium and high concentrations. In addition, the changes in catalase (CAT) and peroxidase (POD) activity were not obvious. Experiments showed that microplastics could significantly inhibit the growth and development of tobacco and reduce the accumulation of aerial parts and root biomass.