Cell and Tissue Journal

Abstract Aim: The aim of the present study was to investigate the effect of lead concentrations on the growth, antocyanin, chlorophyll, carotenoid, total soluble sugars, reducing sugars and free amino acids of harmal (Peganum harmala L.) populations.  
Material and methods: Plants of two different Peganum harmala populations (metallicolous and non metallicolous) were grown in hydroponic condition. Then plants were exposed to 0, 5, 10, 25 and 50 ppm Pb for 14 days. Finally, parameters were measured and calculated by spectrophotometer.
Results: Results showed that the increase of Pb concentrations in the nutrient solution reduced root length and there were significant difference between two populations. Chlorophylls and carotenoid pigments were generally decreased by Pb concentrations, especially under the highest Pb treatment (50 ppm) in both populations. Anthocyanin, total soluble sugars and free amino acids were increased in both populations.
Conclusion: The higher amounts of anthocyanin, total soluble sugars and free amino acids in metallicolous population reflecting the higher degree of tolerance to Pb in this population.

Abstract Aim:Periwinkle (Catharanthus roseus) is a medicinal plant as a result of which its medicinal compounds and alkaloids have been under a great consideration. Lead is one of the most common heavy metal contaminant in the environment. Induction of oxidative stress is a result of the presence of heavy metals in plant cells. Due to the problem of heavy metal pollution and the dangers of pollution to plant in this study, the effects of oxidative stress caused by the presence of lead on activity of antioxidant enzymes, level of prolin and alkaloid in callus grown on MS medium with different concentrations of lead were investigated.
Material and Methods: Catharanthus roseus seeds were planted in the vase containing Pearlite, then to induce callus, the leaves under the sterile condition were put on the solid MS culture media. Calluses were subcultured after three weeks, the calluses after two subculture were treated with different concentrations of lead nitrate (0, 10 and 50 μM). The activity of antioxidant enzymes and content of proline and alkaloid were assayed .Data analyzed at P ≤ 0.05 level using SPSS software.
Results: The results of this study showed that the activity of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POX), catalase (CAT) and the level of proline and alkaloid as well as lipid peroxidation increased significantly (p < 0.05) in comparison  to control.
Conclusion: Due to induction of oxidative stress, lead was caused an increase in antioxidant enzymes activity and the content of malondialdehyde, alkaloid and proline.

Abstract Aim: The aim of present study was evaluation of IAA and kinetin effects on lead uptake and accumulation in Matthiola flavida.
Material and methods: Metallicolous population of M. flavida was grown in hydroponic condition. Then plants were exposed to combination of 1µM Pb and 0, 1, 10, 100 µM IAA and kinetin for 14 days. Finally, Pb concentration was determined in their aerial parts and roots using a flam atomic absorption. Also their Chlorophyll contents were measured and calculated by spectrophotometer.
Results: Results showed increasing aerial part Pb concentration more than 48 and 110% respectively in 1 and 10 µM IAA comparing to control. A significant decreasing aerial part Pb concentration was observed with increasing of kinetin concentration in culture medium. Root Pb concentration significantly decreased with increasing of auxin and kinetin in nutrient solution. Significant differences in aerial part dry weight were not observed in different IAA and kinetin concentrations in comprising with control.
Conclusion: Increasing aerial part Pb concentration in M. flavida was observed in low concentration of IAA but kinetin did not show clear and positive effects on biomass and Pb concentration.