Figure 3. Effect of Cd treatment in Murashige–Skoog (MS) medium and tap water on chlorophyll content (Chl) and photosystem II efficiency of barley (Hordeum vulgare L.) primary leaves. Plants were grown hydroponically in MS medium or in tap water for 10 d and then exposed for 48 h to 1 mM Cd. Each data point represents the mean value of 10 measurements (n = 10 different plants from two independent growth experiments). Error bars indicate the standard deviation (± SE).