Toxicologlcal Effects Of Nitrogen Stress On Caenorhabdiits Elegans Based On HSPs Responses

Since the nitrogen fertilizer could be produced by human, most of the world’s cropsgrowth was largely depended on the application of nitrogen fertilizer, but the unreasonableapplication of nitrogen fertilizer aroused the environmental problems such as watereutrophication. In order to investigate the effects of excess nitrogen on body, we selectedCaenorhabditis elegans (referred to as C. elegans) as the model organism, C. elegans wereexposed to different concentrations of nitrate (dose:0,0.23,2.3,23g/L nitrate) andammonium(dose:0,0.15,1.5,15g/L ammonium).High concentration of nitrate in the water caused mortality, reduced the head swingingrate and productive rate. Under acidic conditions, the sodium nitrate solution have an impacton survival rate of Caenorhabditis elegans (N2), the head slew rate and reproduction ratedeclined. When the pH value is9.0, the survival rate, the head slew rate was significantlyhigher than the pH value is8.0. Ammonium chloride solution under acidic conditions, thesurvival rate, the head slew rate and the reproduction rate of Caenorhabditis elegans (N2)showed a good correlation with the pH value.At the molecular level, HSP12.2expression of C. elegans under N stress has no change.HSP90and HSP70under nitrogen stress have specific performance. On this basis we changedthe pH value to the combined stress, exposure to the different pH value caused mortality andother responses (increased head swinging rate and productive rate) in the populations. Thesetoxic effects showed a concentration-dependent N stress， and the nematodes stress proteins(HSPs) show good dose-response relationship may be biomarkers of stress as a nitrogenfertilizer.