Madeh Ahmadi; Azim Ghasemnezhad; Mansour Ghorbanpour
Abstract
In order to investigate the effect of some biotic and abiotic elicitors on yield and yield components of stevia plant under different salinity stress, the present study has been perfoemed as a factorial experiment based on the randomized complete design with six replications. It has taken place in a ...
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In order to investigate the effect of some biotic and abiotic elicitors on yield and yield components of stevia plant under different salinity stress, the present study has been perfoemed as a factorial experiment based on the randomized complete design with six replications. It has taken place in a greenhouse under hydroponic and conditions in two consequential experiments. Endophytic fungi isolated from yew (at three levels of control, TB20, TB2-3), foliar treatment with melatonin (at three levels of control, 0.5 μM melatonin tablets, and 0.5 μM Thymus vulgaris extract), and three salinity levels (without salinity, medium salinity 80mM, and high salinity 150mM) have incorporated the present experiments’ treatments. The experimental plants have been investigated based on morphological parameters. In both experiments, results show a positive effect of melatonin and endophytic fungi on characteristics of plant growth’s improvement (one to two times) under salinity stress. Nevertheless, the best growth conditions have been observed in low salinity levels, using thyme extract and TB20 endophytic fungus. Most traits of stevia plant in non-saline conditions along with thyme extract and endophytic fungus TB20 have been at their highest, showing an increase of approximately 1.5 folds, compared to the control. Due to the positive effects of melatonin and endophytes, especially TB20, it is recommended to use melatonin-containing plant extracts as a protective treatment in stevia cultivation in saline conditions.
Raheleh Sadat Aletaha Maki; Ali Akbar Safari Sinegani; Doustmorad Zafari
Abstract
In highly stressed ecosystems, symbiosis between plants and has beneficial effects on plant growth. The objective of this study was the effects of two dark septate endophyt fungi against mycorrhizal (Glomus mussea and Glomus interaradices) and Piriformospora indica on Spinach growth in without and with ...
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In highly stressed ecosystems, symbiosis between plants and has beneficial effects on plant growth. The objective of this study was the effects of two dark septate endophyt fungi against mycorrhizal (Glomus mussea and Glomus interaradices) and Piriformospora indica on Spinach growth in without and with drough stress (Field Capacity (FC) and 50% FC). This study was done at Bu- Ali sina university of Hamedan greenhouse (2015-2016). The percentage of root colonization, wet and dry weights, contents of chlorophyll and some of micro- and macronutrients have been analysed in some adult treated plants after six weeks. The colonization results showed that all studied fungi can effectively enter into spinach roots. Inoculation with Glomus mussea increased the wet weight (20 g/plant) of the plants. Also, some morphophysiological and physological properties such as dry weight (4.1 g/plant), chlorophyll content (2.7 mg/gwd) and potassium to sodium ratio (8.4) were increased when plants inoculated with Curvularia specifera. However, high phosphorus content (311.2 mg/100gwd) measured in plants that was inoculated with Glomus interaradices. Generally, this study shows dark septate endophyte could be benefical in grwoth of spinach as much as mycorrhizal and Piriformospora indica symbiosis.
Zahra Noori Akandi; Hemmatollah Pirdashti; Yaser Yaghoubian; Valiollah Ghasemi Omran
Abstract
In order to evaluate the effect of Piriformospora indica fungi inoculation on antioxidant systems and photosynthetic pigments of Stevia under salt stress, an experiment was conducted in a factorial based completely randomized design with four replications under in vitro culture conditions. Factors include ...
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In order to evaluate the effect of Piriformospora indica fungi inoculation on antioxidant systems and photosynthetic pigments of Stevia under salt stress, an experiment was conducted in a factorial based completely randomized design with four replications under in vitro culture conditions. Factors include salinity at six levels (0, 50, 100, 150, 200 and 250 mM of NaCl) and inoculation of mycorrhizae like fungi at two levels (non-inoculated and inoculation with fungi). The results showed that the hydrogen peroxide (H2O2) and malondialdehyde (MDA) concentration and catalase (CAT) activity was increased linearly in control plants while in inoculated plants fitted by a segmented equation. Accordingly, in mild stress the activity of these enzymes were reduced. Chlorophyll a, b and a+b content changed as a segmented model in both inoculated and uninoculated plants. Carotenoid content, however, linearly decreased in both inoculated (slope of -0.007) and uninoculated (slope of -0.005) plants. In conclusion, the results indicated that P. indica, particularly in low levels of salt stress, could reduce hydrogen peroxide (by two percent up to 124 mM of NaCl) and malondialdehyde content (17 percent up to 50 mM of NaCl) which resulted in decreased antioxidant activities and improved photosynthetic pigments and relatively increased tolerance to salt stress in stevia plants.