The determination of the effect of microplastic pollution on plant growth and cadmium (CD) accumulation in Lactuca sativa L. (lettuce)

Plastics are one of the most important pollutants because decomposition of them is difficult in nature and requires a very long time. Plastics break down into smaller pieces through decomposition, abrasion and fragmentation, lead to microplastic (MP) pollution. In this study, it was tried to determine the effects of microplastics obtained by using mulch produced from polyethylene, which is used as a covering material in agriculture, on plant growth and cadmium (Cd) accumulation in lettuce (Lactuca sativa L.). The study was carried out with five experimental sets, as the control group, 2 experimental groups with MP added at different concentrations (1,5 and 2,5%), and 2 experimental groups formed by adding Cd to the medium in which MP was added at different concentrations. Above ground fresh weight (TA) and dry weight (KA), below ground TA and KA, above ground length and root length, above and below ground water content and Cd concentrations were measured and statistically evaluated in lettuce seedlings. As a result, it was determined that there were significant variations between the experimental sets in the values of above-ground KA, below-ground TA, above-ground length, topsoil water content (TÜSĠ) and subsoil water content (TASĠ). The addition of MP caused anincrease in some parameters and a decrease in others. The addition of Cd to the microplastic environment changed the plant's response to microplastic exposure in many parameters. It was determined that the Cd concentration in the leaves of lettuce seedlings increased as the amount of microplastic added to the soil increased. The results show that these two pollutants may have different effects on plant growth in environments where they coexist and increase the effects of Cd toxicity by causing more Cd accumulation. It is thought that these findings will be beneficial in terms of plant development and yield, healthy food supply, sustainability of ecosystems and environmental health.