85 Advances in Environmental Biology, 6(1): 85-88, 2012 ISSN 1995-0756 This is a refereed journal and all articles are professionally screened and reviewed ORIGINAL ARTICLE Corresponding Author Bouchelaghem Sabrina, Laboratory of Cell Toxicology. University of Annaba, BP12, 23000. Algeria. E-mail: Sabrina_bouchelaghem@yahoo.fr Induction of Antioxidant Enzyme System by A Nitrogen Fertilizer Npk in Wheat Triticum Durum. 1 Bouchelaghem Sabrina, 2 Djebar Mohammed Réda and 3 Et Berrebbah Houria 1,2,3 Laboratory of Cell Toxicology. University of Annaba, BP12, 23000. Algeria. Bouchelaghem Sabrina, Djebar Mohammed Réda and Et Berrebbah Houria; Induction of Antioxidant Enzyme System by A Nitrogen Fertilizer Npk in Wheat Triticum Durum. ABSTACT In this work we were interested in assessing the impact of nitrogen fertilizer NPK on the roots and stems of wheat Triticum durum. We followed the biomarkers of toxicity of GSH, GST, and MDA, after seven days of treatment, there is an inhibition of root GSH and increased GST roots, so there is a stimulation of the synthesis of MDA activity in roots and stems of wheat which results in an outbreak detoxification enzyme system. Key words: NPK, Triticum durum, roots, stems, GSH, GST, MDA. Introduction Fertilizers are substances, usually mixtures of minerals, designed to provide the plants with additional nutrients, in order to improve their growth and increase yield and crop quality. The plants need relatively large amounts of basic elements, macroelements. Nitrogen, phosphorus and potassium are the elements to be added to the soil usually poor or depleted by intensive crops. However, the presence of fertilizers in high concentrations can cause an inhibition of growth and development of plants. [1] The objective of this study is to evaluate the effects of nitrogen fertilizer NPK on physiological parameters, metabolic, and on biomarkers of environmental stress (GSH, GST, MDA) in wheat Geta drive. Materials and Methods Biological Material: The experimental material used in our work is wheat (Triticum durum) Geta come from hard JTGC (demonstration farm and seed production Guelma). Culture Of Seeds: The seeds of wheat are grown by the method of Kaur and Duffus [2] for a period of seven days, ten seeds are first randomly selected and are then placed in a Petri dish placed blotting paper, soaked with 8 ml of distilled water at the average temperature of 20 ⁰ C. Seed Treatment: Seed treatment is made from prepared solutions of increasing concentration based NPK. Determination of MDA and GSH: The extraction of MDA is in 10 ml of trichloroacetic acid (TCA), followed by a 12000 g centrifugation for 15 min, the supernatant was added an equal volume of thiobarbituric acid (TBA) 0.5% in 20% TCA and the at 100 ⁰ C for 25 minutes. The absorbance of the supernatant obtained after centrifugation at 10,000 g for 5 min was read at 532nm. Alia et al. [3] The extraction of GSH in 4 ml of 100 mM phosphate Tempone, followed by deproteinization in acid sulfo-Sally-Silique 0.25% after centrifugation at 2000g for 10 min, the absorbance of the supernatant is at 412 nm in the presence of 25μl of DTNB Anderson, [4]. Enzymatic Assay: Determination of Glutathione S-transferase activity (GST): Measurement of glutathione S- transferase is achieved by the method Habig et al., [4]. Figure 1 shows an induction of GSH in the stalks of wheat. Unlike in the roots, we note that the amount of GSH undergoes regressive growth under different levels of NPK (Figure 2).