Investigation of the effect of clover (Medicago sativa L.) cultivation on the biochemical properties of pesticide applied soils

In this study, pesticides used in agricultural fields were applied in different doses to alfalfa (Medicago sativa L.) plant (B) and plantless potted soil (T); no pesticide (P0), suggested pesticide dose (P1), the suggested pesticide dose 3 times (P2), the suggested pesticide dose 9 times (P3). Soil samples were taken from all pots on the 15th, 30th and 45th days of pesticide application, and some soil enzymes (urease, dehydrogenase (DHG), soil catalase) and soil pH, electrical conductivity (EC) were determined. Development of harvested alfalfa plant (fresh wet weight (YA), dry weight (KA), and biochemical responses (chlorophyll-a (Chl-a), chlorophyll-b (Chl-b), proline, catalase (CAT), and peroxidase (POX) antioxidant the effect of increasing pesticide doses on alfalfa plant was found to be statistically significant (P≤0.05). While YA, KA, Chl-a and Chl-b contents of alfalfa plant decreased with increasing pesticide dose, proline content, POX and CAT antioxidant enzyme activity increased compared to control. It was observed that there was a decrease in CAT antioxidant enzyme activity in the application of 9 times the suggested dose.The effect of increasing pesticide doses on urease, DHG, soil catalase, pH and EC contents in planted and plantless soils was found to be significant (P≤0.05). Urease and DHG enzyme contents in clover soils increased compared to plantless soils, while soil catalase, pH and EC values decreased. This showed that the alfalfa plant positively affected the soil exposed to pesticides. It has been revealed that alfalfa increases the biochemical quality of the soils and thus can be used as a healing plant in the phytoremediation method.