CONTRIBUTION TO THE STUDY OF THE IMPACT OF A FERTILIZER COMMONLY USED IN ALGERIA (NPK) ON GERMINATION AND RESPIRATORY METABOLISM OF TRITICUM DURUM

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1 Proceedings of the 13 th International Conference of Environmental Science and Technology Athens, Greece, 5-7 September 2013 CONTRIBUTION TO THE STUDY OF THE IMPACT OF A FERTILIZER COMMONLY USED IN ALGERIA (NPK) ON GERMINATION AND RESPIRATORY METABOLISM OF TRITICUM DURUM BOUCHELAGHEM SABRINA, DJEBAR MOHAMMED REDA 1 Laboratory of Cell Toxicology. University of Annaba, Algeria. . Sabrina_bouchelaghem@yahoo.fr ABSTRACT In this study we were interested in assessing the impact of different NPK regimes and their effects on wheat Triticum durum. The preliminary results show that the presence of the fertilizer causes a decrease in the percentage and speed of germination and inhibition of the growth of wheat. In our work, we have demonstrated an inhibition of the respiratory activity of roots in the presence of different regimes of NPK. And inhibition of respiration and photosynthesis of plantlets of wheat seeds in the presence of NPK. Keywords: Triticum durum ; NPK ; germination, photosynthesis; respiration, roots. Leaves 1. INTRODUCTION Fertilizers are used to obtain greater crop yields, but are responsible for massive pollution of soil and water, in fact, their use poses serious problems for the environment and human and animal health. Fertilizers are a source of nutrients that provide the plant growth and disease resistance. Over-fertilization leads to pollution of soil and water with a high concentration of nitrates and phosphates. (ANCA et al. 2006) The aim of this study is to evaluate the effects of nitrogen fertilizer NPK on physiological and respiratory metabolism of Triticum durum. 2. MATERIALS AND METHODS 2.1 Biological material The experimental material used in our work is wheat (Triticum durum) Geta hard to come JTGC (demonstration farm and seed production Guelma). 2. Culture seeds The wheat seeds are grown according to the method of Kaur and Duffus (1989) for a period of seven days Ten seeds are first randomly selected and are then placed in Petri dishes arranged blotting paper, soaked with 8 ml of distilled water at the temperature of 20 ⁰ C. 2.2 Seed treatment Seed treatment is carried out from solutions of increasing concentration prepared based NPK. We selected 4 concentration and a control medium without NPK (0.5, 0,1. 0,1), (0,5.0,2.0.1). (0,5.0,3.0,1). And (0,5.0,4.0,1). Please do not use page numbers

2 2.3. Respiratory metabolism Oxygen consumption related respiratory oxidation is measured by the technique of using a polarographic oxygen electrode coupled to a microcomputer. The cell of a volume adjustable from 1 to 2 ml is thermostated at 25 C C. The measuring medium is stirred vigorously and is composed of distilled water. 3. RESULTS 3.1 Effects of various treatments NPK on growth and physiological parameters of germination. Effects on germination percentages Figure 1: Effect of different NPK regimes on the average germination of wheat germination time (96h). P = Effects on the germination speed: speed values of seed germination of wheat are shown in Figure (2). Figure 2: Effects of different regimes of NPK on the speed of germination of wheat germination time (96h).

3 Effect of NPK treatment on mean shoot height Figure 3: Effects of NPK treatments on the average length of seedling stems from wheat seeds after 7 days of treatment. Effect of NPK on the respiratory metabolism of roots The evolution of the respiratory metabolism of the roots of wheat seeds subjected to treatment with different concentrations of NPK is presented in Figure 4 Figure 4: Recording of the respiratory activity of wheat roots subjected to treatment with different NPK regimes after 7 days of treatment.

4 Effect of NPK on the respiratory metabolism of wheat stem Figure 5: Evolution of respiratory activity stems after wheat seedlings in the presence of different regimes of NPK. After 7 days of treatment. 4. DISCUSSION In this part of our work, we determined the effects of NPK on germination percentage and where we observed a decrease in this parameter regime especially (0,5:0,4:0,1) (20%). Our results are in perfect agreement with the work of Savoy and Smith (1997) who showed that germination decreased with increasing nitrogen concentration. For the second measurement parameter namely the speed of germination we recorded a more marked effect on proportions (0,5:0,4:0,1) NPK showing that changes in concentrations of these three elements (N, P, K) could have a negative effect on plant growth indicating toxicity. The overall results obtained in this part of our work watches treatment isolated wheat roots greatly reduces respiratory activity. This inhibition is firstly due to the presence of ROS, which are known as disruptive element as well as the respiratory metabolism photosynthesis (Kiss et al, 2003; kuciel and Mazurkiewicz, 2004) and on the other hand it could be explained by in that the various components of the fertilizer (N, P, K) may interfere in respiratory metabolism so directly on the mitochondrial respiratory chain. Indeed, it has been shown only at the roots of durum some voltage-dependent calcium channels of the plasma membrane known as (RCA) and which control the ΔΨ (Pototiel pressure) membrane are permeable to micronutrient and those in the presence of Calcium (White, 2000). Parallel the results obtained in our work, we can see that both respiration than photosynthesis are inhibited by NPK plantlets in wheat grains. This effect is then due to the disruption of mitochondrial oxidative phosphorylation (Chagra et al, 2009). This disturbance can be explained by the interference of phosphorus in respiratory enzyme activities and consequently in the mechanism of oxidative phosphorylation. 5. CONCLUSIONS The presence of NPK in the protoplasm leads to disturbances in the ionic balance at the level of membrane enzymes and other macromolecules. These disturbances lead to low energy production by phosphorylation and photo-respiration, nitrogen assimilation

5 disturbed and altered many metabolic pathways. If the concentration of fertilizer exceeds the tolerance level of the plant functional disturbances appear at photosynthesis, in fact, the presence of NPK in the chloroplast stroma disrupts the electron transport. Glycolysis and the Krebs cycle are also affected. The acquisition of mineral nutrients, such as potassium nitrate or calcium is also reduced. Growth of wheat is disrupted by excessive concentrations of fertilizer. When the plant shows signs of stress in the destruction of chlorophyll. REFERENCES 1. Anca H., Ovidiu T., Eugen U., Lucian N., L influence des nitrates et des nitrites sur les activités de la catalase et de la peroxydase au cours de la germination des graines de Triticum aestivum. Analele stiinfice ale Universitatii, Alexandu loan Cuza, sectiunea Genetica si biologie Moleculara, 7: Chagra A., Djebar M.R., Rouabhi R., et Berrebbah H., Cadmium induced changes in metabolic function of mitochondrial isolated from potato tissue (Solanum tuberosum L.). American journal of biotechnology, 3. Kaur J, Duffus C., The effect of naf on cereal seed germination and seeding growth. Plant Cell and environnement. 12 : Kiss, S.A., Varga, I.S., Galbacs, Z., Maria, T.H., Csikkel-Szolnoki, A., 2003 : Effect of age an magnesium supply on the free radical and antioxydant content of plants. Acta Biologica Szegediensis, Vol.47 (1-4), pp, Kuciel, R., Mazurkiewicz, A., 2004: Formation and Detoxification of reactive oxygen species.biochemestry and Molecular Biology Education, Vol.323, pp, White, P.J., Calcium channels in higher plants Biochimica and Biophysica Acta. 1465: