In last decades the weight of agricultural ma -chines has increased and consequently the soil compaction has increased due to the use of such machines under wet soil conditions (Abu-Hamdeh 2003). In wet and cold springs, such compacted soils may be waterlogged and plants show visual symptoms of water logging. On waterlogged sites, plants show chlorosis and necrotic spots on older leaves. Both Mn toxicity and N deficiency may be induced by the low redox potential in water-logged soils that produces plant-available Mn2+and promotes denitrification of NO3–. Under these anaerobic conditions, root metabolism and root growth are inhibited, since the lack of O2 affects the energy status of the plant (Drew 1988). Water logging reduces leaf superoxide dismutase activ -ity, leaf catalase activity, and root oxidazibility of Brassica napus L. (Zhou and Lin 1995). Gutierez Boem et al. (1996) reported that water logging resulted in a decrease of N, P, K and Ca uptake by Brassica napus L. On the other hand, water log-ging changes the available ion concentration of the soil solution. Due to electron excess, FeIII and MnIV are reduced to FeIIand MnII, respectively. Rice roots can avoid uptake of the accumulated FeII and MnII ions by a release of oxygen into the rhizosphere for Fe and Mn oxidation (Mengel and Kirkby 2001). Plants such as wheat and barley are not able to oxidize Fe and Mn so that a toxicity of Mn and Fe may occur under waterlogged condi-tions (Drew 1988).The objective of this study was to analyse whether water logging and oxygen deficiency inhibit the growth of spring barley and spring wheat primarily by a deficiency or by a toxicity of nutrients