Mehri Mashayekhi; Fariborz Habibi; Mohamad Amiri
Abstract
Mechanisms of drought stress tolerance of GF677 rootstock, peach and almond hybrid, (Prunus persica × Prunus amygdalus) were studied under in vitro conditions. Plantlets of GF677 rootstock were subcultured into the Murashige and Skoog (MS) solid proliferation medium containing 1 mg/l BA (6-Benzyladenine) ...
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Mechanisms of drought stress tolerance of GF677 rootstock, peach and almond hybrid, (Prunus persica × Prunus amygdalus) were studied under in vitro conditions. Plantlets of GF677 rootstock were subcultured into the Murashige and Skoog (MS) solid proliferation medium containing 1 mg/l BA (6-Benzyladenine) and 0.1 mg/l NAA (naphthaline acetic acid) in four drought stress levels 0 (control), 10, 20 and 30 g/l polyethylene glycol 6000 (corresponding to osmotic potentials 0, -0.2, -0.4 and -0.6 Mpa, respectively). After six weeks results showed that induced drought stress had a significant effect on measured parameters. By increasing drought levels in the culture medium, antioxidant enzymes activity (catalase and peroxidase), total protein content and proline content significantly increased; meanwhile soluble sugars had non-significant increasing in the different levels of drought. According to the results it can be concluded that, the most important mechanisms of drought tolerance of GF677 rootstock under in vitro conditions are the use of antioxidant defense system, increasing protein synthesis (enhancing genes expression) and proline accumulation and osmoregulation by soluble sugars had less important.
mahdi mohammad zan=mani; vali rabiei; Mohammad Ali Nejatian; Mehdi Taheri
Abstract
Proline and glycine betaine are the most common compatible solutes that prevent plants from destructive effects of osmotic stresses by osmotic adjustment and protection of membranes, proteins and enzymes. It has been reported that exogenous application of these compounds, can increase plant resistance ...
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Proline and glycine betaine are the most common compatible solutes that prevent plants from destructive effects of osmotic stresses by osmotic adjustment and protection of membranes, proteins and enzymes. It has been reported that exogenous application of these compounds, can increase plant resistance to drought stress. Therefore a factorial experiment based on randomized complete block design with four replications was performed in four grapevine cultivars (‘Khushnav’, ‘Peykani’, ‘Perlette’, and ‘Flame Seedless’). Grapevines were irrigated by 70 percent of the vine water requirement, in drought stress treatment. Proline (10 mM) and glycine betaine (15 mM) were sprayed on grapevines at four growth stages (before flowering, flowering, sour cluster and veraison). Results showed that endogenous proline and amount of glycine betaine, peroxidase and ascorbate peroxidase enzyme activity in treated vines were significantly higher than the control, in both proline and glycine betaine treatments. Among of the treated vines, the most and the least amount of proline was measured in ‘Flame Seedless’ and ‘Peykani’, respectively. Other measured traits in cultivars did not show significant difference. According to the role of these enzymes in eliminating reactive oxygen spices (ROS) and also the role of proline and glycine betaine in antioxidants activating, using of these two osmolytes will be able to increase the vines tolerance to drought stress conditions.