Ali Akbar Ehsanpour; Somayyeh Zarei; Jalil Abbaspour
Abstract
In this study proline content and activity of catalase (CAT), and ascorbate peroxidase (APX) and level of lipid peroxidation in terms of malondialdehyde (MDA) content were measured in transgenic tobacco (Nicotiana tabacum cv. Wisconsin), over expressing a Δ-1-pyrroline-5-carboxylate synthase (P5CS) ...
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In this study proline content and activity of catalase (CAT), and ascorbate peroxidase (APX) and level of lipid peroxidation in terms of malondialdehyde (MDA) content were measured in transgenic tobacco (Nicotiana tabacum cv. Wisconsin), over expressing a Δ-1-pyrroline-5-carboxylate synthase (P5CS) gene, and non transgenic plants as control. Drought stress was applied using polyethylene glycol (PEG) 6000 at concentrations of 217, 264, 320, 637, 1292 mmol/kg equal to (0, 5, 10, 20, 30% respectively). Proline content, especially in transgenic plants, was increased in leaves and roots significantly. CAT and APX activities increased under drought stress and the highest activity was observed in 10 and 20% of the PEG treatment. MDA content was increased by increasing of PEG and the highest MDA content was revealed in transgenic and non transgenic plants at 20% and 30%, respectively. Our results suggest that P5CS is an inducible gene and over production of proline and induction of CAT and APX activities are involved in drought tolerance mechanism.
aliakbar ehsanpour; Behrokh Shojaie; Mohammad Reza Abdi
Abstract
In this study, the effects of gamma rays on changes of proline, sodium and potassium in potato calli
(Solanum tuberosoum L.) cultivar "White Desiree" were investigated. After irradiation of calli by 60 and 80 Gy
of gamma radiation, irradiated and non irradiated calli were transferred to a callus production ...
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In this study, the effects of gamma rays on changes of proline, sodium and potassium in potato calli
(Solanum tuberosoum L.) cultivar "White Desiree" were investigated. After irradiation of calli by 60 and 80 Gy
of gamma radiation, irradiated and non irradiated calli were transferred to a callus production medium
containing 0, 30, 60, 90, 120 and 150 mM NaCl. After 26 days post treatment amounts of proline, Na+ and K+
were measured. The results showed that generally in each of gamma ray treatment, amounts of proline at 120
and 150 mM NaCl were significantly more than 0, 30, 60 and 90 mM salt. A significant difference observed
only at 150 mM NaCl between irradiated and non irradiated calli. This result could be related to the proline
role in osmotic adjustment at high concentration of salt. The amounts of sodium increased by increasing salt
the concentration but the amount of potassium decreased. These results showed that the sodium influx
inhibited the potassium uptake, and may be because of strong inhibitory effect of sodium on the potassium
uptake system or efflux potassium from the cells. The Na+/K+ ratio decreased at 150 mM by 60 and 80 Gy of
gamma radiation.
