Lallemantia royleana (Nazboo, Black psyllium or Balangu) is an important medicinal plant of Iran which is belonged to Lamiaceae family. The plant is very interesting for traditional medicine in different area of world especially Asian countries and extracted mucilage from the seed of this plant has many applications in food science and also modern pharmacology. In order to study the effects of cadmium stress on biochemical traits of Lallemantia an experiment was conducted in experimental greenhouse of Malayer University based on completely randomized design (CRD) with four replications. Different concentration of cadmium (0, 2.5, 5, 10 mg.l-1) was made using CdCl2 and used for irrigation of lallemantia pots. Based on results effects of different levels of cadmium on antioxidant enzymes of Lallemantia were significant but the observed trend wasn’t similar. By increasing the concentration of cadmium amounts of superoxide dismutase (SOD), ascorbate peroxidase (APOX) and peroxidases (POX) activity increased linearly but the effects of cadmium on catalase (CAT) activity was different. By increasing the cadmium concentration up to 5 mg.l-1 the activity of CAT increased but in higher concentration (i.e. 10 mg.l-1) CAT activity decreased significantly. The trend of change in activity of antioxidant enzymes was similar in root and leaf of Lallemantia but in all of the measurement the observed values for root were higher than leaves. Significant increase of antioxidant enzymes mean that oxidative stress started in the plants because of cadmium toxicity.
