Z. Valinezhad; A. Gholizadeh; M. Naeemi; E. Gholamalalipour Alamdari; M. Zarei
Abstract
In order to investigate the effect of vermicompost and mycorrhizal fertilizers on Stevia rebaudiana Bertoni, a factorial experiment was conducted in a completely randomized design with four replications in the research greenhouse of Agriculture College of Gonbad Kavous University in 2016-2017. The First ...
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In order to investigate the effect of vermicompost and mycorrhizal fertilizers on Stevia rebaudiana Bertoni, a factorial experiment was conducted in a completely randomized design with four replications in the research greenhouse of Agriculture College of Gonbad Kavous University in 2016-2017. The First factor was vermicompost at four levels (0, 10, 20 and 30 % of soil weight) and the second factor was inoculation with biological fertilizers at three levels (no inoculation (control) and inoculation with mycorrhizal fungi Glomus intraradieces and Glomus mosseae about 400 fungi spores per pot). The results showed that all cuttings were gradually eliminated in the treatments containing 30% vermicompost due to its high salinity, and had very low growth in treatments containing 20% vermicompost. The effect of vermicompost and mycorrhizal fungi on all traits studied, except the main effect of mycorrhizal fungi on the number of lateral branches and anthocyanins, were significant at 1% probability level. Also, their interaction was significant for all traits except stem dry weight. Based on the results, the highest positive effect was obtained in application of G. mosseae with 10% vermicompost for morphological traits such as plant height (126.63 cm) and root length (33.75 cm), and G. intraradieces with 10% vermicompost for flower (1.03 g) and root (9.93 g) dry weight and leaf area (78212 cm2) compared to no inoculation of mycorrhizal fungi at different levels of vermicompost. The highest content of chlorophylls a and b and total chlorophyll, and carotenoids (1.25‚ 1.58‚ 2.83 and 1.08 mg gr-1) was obtained in application of G. intraradieces with 10%vermicompost. The maximum content of soluble sugars (158.15 mg gr-1) was observed in 10%vermicompostwithout mycorrhizal inoculation treatment. According to the results of this study, the use of G. mosseae and G. intraradices fungi together with 10% vermicompost had the most positive effect on the quantitative and qualitative characteristics of Stevia rebaudiana.
S. Shiati; J. Khara; A. Hassanzade Ghort Tapeh
Abstract
Among the different types of mycorrhizas, arbuscular mycorrhiza is the most common peaceful type of symbiosis between the land microorganisms and plants with a great economic and ecological importance. On the other hand, UV irradiation is known to cause oxidative damage to plants by triggering an increased ...
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Among the different types of mycorrhizas, arbuscular mycorrhiza is the most common peaceful type of symbiosis between the land microorganisms and plants with a great economic and ecological importance. On the other hand, UV irradiation is known to cause oxidative damage to plants by triggering an increased level of production of reactive oxygen species (ROS). The objective of the present investigation was to study the effects of mycorrhiza on physiological traits of flax (Linum usitatissimum L.) under UV stress. The flax plants were grown in two mycorrhizal (M) and non-mycorrhizsal (NM) groups with a diurnal regime of 16 hour light and 8 hour dark at 18-29°C. Mycorrhizal plants were colonized by inoculum obtained from Glomus versiforme and Glomus etunicatum culture. They were divided after 21 days of growth. One set of pots served as the control, and the other set was treated with UV radiation (312nm) for 1 hour each day for 14 days. The study was conducted in a completely randomized design including three mycorrhizal treatments (with G. etunicatum, G.versiforme and without mycorrhiza), and two UV treatments (with UV and non-UV) in three replications. Results showed that chlorophyll a and chlorophyll b content was significantly reduced in treated plants in comparison with the control. This decrease was less obvious in mycorrhizal plants as compared with non-mycorrhizsal samples; however, antioxidant enzymes activity increased when plants were irradiated with UV light. This increase was more dramatic in mycorrhizal plants samples than non-mycorrhizsal ones. In addition, results showed that malondialdehyde content was increased when plants were irradiated with UV light. This increase was more dramatic in non-mycorrhizsal samples than mycorrhizsal ones. According to the obtained results, it is concluded that UV-B stress has serious effects on Shahin-dezh cultivar and mycorrhizal symbiosis with the two fungi species can somewhat reduce this stress. Furthermore, colonization with Glomus versiforme resulted in better ameliorative effects on plants in comparison with Glomus etunicatum.
M. Otroshy; F. Vafadar Esfehan; R. Amooaghaie
Abstract
Stevia rebaudiana Bert.is a medicinal plant, mostly utilized as a suitable sweeter for diabetic patients. In this research, the effect of single or co-inoculation of Arbuscular Mycorrhiza Fungi (AMF) and bacteria (Bacillus polymixa, Pesudomonas putida and Azotobacter chroococcuom) on regenerated plantlets ...
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Stevia rebaudiana Bert.is a medicinal plant, mostly utilized as a suitable sweeter for diabetic patients. In this research, the effect of single or co-inoculation of Arbuscular Mycorrhiza Fungi (AMF) and bacteria (Bacillus polymixa, Pesudomonas putida and Azotobacter chroococcuom) on regenerated plantlets in tissue culture was investigated in intervals of 15, 30, 45, 60 days after planting. Results showed that in comparison to control, inoculation with single and triple treatments significantly increased length, fresh and dry weight of aerial parts and stevioside content until 60 days after planting while the best enhancement was observed in dual inoculations especially in Glomus+Azotobacter treatments. Interestingly, in dual or triple inoculations, maximum relative growth rate was obtained in 15-30 days and reduced in 30-45 days after planting that was in accordance with their flowering time but in single inoculation maximum relative growth rate was available in 30-45 days and with promoting of flowering phase in 45-60 days declined severely. However, maximum stevioside accumulation rate was obtained 30-45 days after planting in all treatments and in 45-60 days after planting reduced severely in single or triple inoculations and more slightly in dual inoculations. Therefore, microorganisms affect relative growth rate, phenology and stevioside accumulation pattern in stevia.
