Abstract : The use of phytosanitary products is called into question, with the risks they can cause for the environment and human health. These chemical solutions can cause considerable damage to crops and can cause an overproduction of ROS (Reactive Oxygen Species) which results in chlorosis and necrosis visible to the naked eye, up to the premature death of plants. This scientific contribution aims to verify in the laboratory the effect of a Difenconazole on the agronomic parameters, the biochemical indicators and the components of the yield of a pea legume (Pisum sativum subsp. Sativum var. Sativum). Four treatment doses were chosen with control, namely Dose 1 (0.5 ml/l), Dose 2 (1 ml/l), Dose 3 (1.5 ml/l) and Dose 4 (2 ml/l). All the variables studied of the batches treated with the low doses D1 and D2 note a low antioxidant biochemical activity and higher yields, on the other hand the batches treated with the high doses D3 and D4 recorded a high biochemical activity, namely Proline, GSH, GST with apparent antioxidant stress and low yield components. The dose effect is decisive and proportional to the doses applied.