The effects of gibberellic acid on certain physiological parameters in alfalfa (Medicago sativa L.) under cadmium stress.

Abstract

Alfalfa is one of the most important forage corps in the world. The Medicago plant is a major genus from the fabaceae.High concentration of heavy metals in soil is one of the most important problems in the environment . Cadmium is a heavy metal that can cause oxidative stress in plant cells. In this research effects of different concentrations of cadmium (0 , 25 and 50 µM) and gibberellic acid (0 , 5 and 10 µM) were investigated on certain physiological parameters in Medicago sativa L. Alfalfa seeds were sterilized and cultured in pots containing sand which were irrigated with Hoagland nutrient solution. plants were treated with cadmium chloride and gibberellin 22 - old day.after twenty two days Plants were harvested to assay some physiological parameters. All treatments were conducted with four replications. Experiment results showed that increasing cadmium chloride concentration in Hoagland nutrient solution, decreased growth parameters and pigment contents and GPX activity.But , but proline contents, SOD and CAT activties in roots and leaves of plants increased. by additionof gibberellin concentrations. . It is concluded that gibberellic acid could alleviate the adverse effects of stress cadmium chloride in Medicago sativa L.

Keywords

• key words: oxidative stress
• . heavy metals
• gibberllins
• medicago sativa
• stress