Abstract

Farzaneh Najafi , Ramazan Ali Khavari-Nejad, and Fatemeh Hasanjanzadeh

The effects of different concentrations of nickel sulfate (NiSO4) on some physiological parameters in sunflower (HELIANTHUS ANNUUS L.) were studied. Sunflower plants were treated with NiSO4 at 0, 4, 8, 16, 32 and 40 µM in Hoagland solutions. With the increasing concentrations of NiSO4, all the growth parameters increased. The highest significant increase of NAR and RGR were obtained with 16 µM NiSO4. Control and treated plants had similar chlorophylls and unsoluble sugars contents. Total soluble sugars and protein contents were increased in high concentrations of NiSO4. Addition of all nickel concentrations had a significant promotive effect on Mn, Fe and Ni contents in leaves and roots as compared to that of control. Malondialdehyde (MAD) and respiration rate were significantly increased in high concentrations, however, photosynthetic rate and RWC decreased in all concentrations of NiSO4.