Improvement and breeding
E. Danaee; V. Abdossi
Abstract
Salinity is one of the most important abiotic environmental stresses which restricts the growth and production of plants. On the other hand, silicon (Si) is the second most abundant element in the soil and alleviates the biotic and abiotic stresses in the plants. For this purpose, a greenhouse experiment ...
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Salinity is one of the most important abiotic environmental stresses which restricts the growth and production of plants. On the other hand, silicon (Si) is the second most abundant element in the soil and alleviates the biotic and abiotic stresses in the plants. For this purpose, a greenhouse experiment was conducted as a factorial in a completely randomized statistical design with three replications to investigate the effects of silicon and nano-silicon (50 and 100 mg l-1) on some morphophysiological and phytochemical properties of peppermint (Mentha piperita L.) under salinity stress at the different levels of sodium chloride (0, 50, and 100 mg l-1) in 2019. The results showed that the salinity stress significantly reduced the fresh and dry weight of aerial parts and root, and chlorophyll, total phenol, and protein contents. The activity of superoxide dismutase and peroxidase enzymes and essential oil percentage differed at the different salinity levels. The amount of proline also increased significantly due to the sodium chloride treatment of 100 mg l-1. The plants treatment with the different levels of silicon and nano-silicon reduced the negative effects of salinity stress on the evaluated indices. The nano-silicon treatment of 100 mg l-1 showed the highest inhibition of salinity stress effects on the growth indices, antioxidant enzymes activity, and essential oil percentage. Therefore, according to the results of this research, the foliar application of silicon and nano-silicon could be recommended to reduce the negative effects of salinity stress on peppermint.
H. Vosoughi Tabar; S.A. Hosseini Tafreshi; H. Dehghanzadeh
Abstract
In order to investigate the effects of Azotobacter on growth indices, yield and essential oil content of two cumin (Cuminum cyminum L.) landraces under salinity conditions, an experiment was carried out in a factorial design arranged as randomized complete block design with three replications in ...
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In order to investigate the effects of Azotobacter on growth indices, yield and essential oil content of two cumin (Cuminum cyminum L.) landraces under salinity conditions, an experiment was carried out in a factorial design arranged as randomized complete block design with three replications in 2015 at the Kashan University. The treatments included two cumin landraces (Ardestān and Mashhad Ardehal), four salinity levels (control, 100, 150 and 200 mili molar Nacl) and two levels of azotobacter (control and seed inoculation). Results showed that salinity and inoculation with bacteria had a very significant effect on germination rate and percentage, radicle length and plumule height. Increased concentrations up to 200 Mm sodium chloride resulted in a significant reduction in germination percentage and germination rate, radicle length, plumule height, grain yield and essential oil yield. According to the results, in both landraces and at all salinity levels, inoculation with bacteria, resulted in a significant increase in chlorophyll a, b, catalase, ascorbate peroxidase, grain yield and essential oil yield compared to the control. The Ardestān landrace had the highest chlorophyll a and b, catalase, ascorbate peroxidase and essential oil content and tolerated salinity better compared to the Ardehal Mashhad landrace. In salinity conditions, inoculation of seeds with Azotobacter could reduce the negative effects of stress and improve the germination rate, seed yield and essential oil yield. The results of this experiment indicated that Ardestān landrace could be cultivated and used to reduce the effects of salinity due to the inoculation with Azotobacter, and higher grain yield and essential oil yield could be obtained under conditions similar to this experiment.
F. Salimi; F. Shekari; M.R. Azimi; E. Zangani
Abstract
To evaluate the effect of spraying with methyl jasmonate on membrance properties, ion uptake and osmotic adjustment and flower dry weight of chamomile (Matricaria chamomilla L.) under salt stress an experiment was conducted at greenhouse with three replications. The experimental design was factorial ...
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To evaluate the effect of spraying with methyl jasmonate on membrance properties, ion uptake and osmotic adjustment and flower dry weight of chamomile (Matricaria chamomilla L.) under salt stress an experiment was conducted at greenhouse with three replications. The experimental design was factorial based on randomized complete blocks design. The studied factors were as follows: spraying with methyl jasmonate at five levels including, 0, 75, 150, 225 and 300 μM in three growth stages: 1) 3 to 4 leaves, 2) stem elongation and 3) flowering (anthesis) and salt stress applied at four levels of 2.1, 6, 10 and 14 dS/m NaCl. The results showed that spraying with methyl jasmonate and salinity stress had significant effects (p ≤ 0.05) on all measured traits. The highest cell membrane stability, proline, K+, Ca+content, ratio of K+/Na+ and flower dry weight, with the lowest content of Na+ were obtained in spraying 75 µM MeJA and 6dS/m salinity stress. High amount of the mentioned parameters at the concentration of 6 dS/m salinity could be related to the assisting role of MeJA through preventing salt entrance and preferential absorption of K+ in mild salinities compared with the control treatment. In addition, application of MeJA induced significant increase in proline content. It seems that increase in proline content leads to cell membrane stability and salt resistance.
