Agriculture and horticulture
B. Andalibi; M. Mohammadi Azar; B. Esmailpour; F. Shekari
Abstract
This study was conducted to investigate the effects of salicylic acid (SA) and nanosilicon (n-Si) on some morphophysiological characteristics and essential oil of Lallemantia iberica under salinity stress and uncontrolled greenhouse conditions as a factorial experiment based on the randomized complete ...
Read More
This study was conducted to investigate the effects of salicylic acid (SA) and nanosilicon (n-Si) on some morphophysiological characteristics and essential oil of Lallemantia iberica under salinity stress and uncontrolled greenhouse conditions as a factorial experiment based on the randomized complete block design in 2018. The experimental factors included sodium chloride (0, 50, and 100 mM), SA (0, 1, and 2 mM), and n-Si (0, 0.5, and 5 mM). The SA and n-Si treatments were applied at the four-leaf stage (once every seven days) and the salinity treatment was applied at the six-leaf stage of the plant (once every four days) until fully ripening seeds of the plant (yellowing 90% of the leaves and capsules). The results showed that under salinity stress, the plant traits including height, aerial parts dry weight, chlorophyll content, and seed yield decreased and proline and essential oil increased. The application of SA and n-Si improved these traits under salinity stress. The main constituents of L. iberica essential oil included linalool (25%), geraniol (16%), β-cubebene (10.6%), menthyl acetate (9.8%), valencene (3.5%), germacrene-D (2.4%), β-caryophyllene (2.3%), and limonene (1.3%), all of which increased in the salinity treatments compared to the control. The application of SA and n-Si under salinity stress conditions increased limonene, linalool, geraniol, β-cubebene, β-caryophyllene, and valencene and decreased menthyl acetate and germacrene D. In general, the results of this study showed that the application of SA and n-Si could increase the tolerance of L. iberica to salinity stress by creating the osmotic regulation, protecting the content of photosynthetic pigments, and reducing oxidant damage.
M. Zeynali; B. Maleki Zanjani; P. Moradi; F. Shekari; S.M. Niazkhani
Abstract
Biological stresses such as drought affect the production of secondary metabolites, especially plant sterols (phytosterols). Among the phytoestrols found in pumpkin seeds, betasitosterol is one of the most important components which also have many medicinal properties. In this study, the effect of five ...
Read More
Biological stresses such as drought affect the production of secondary metabolites, especially plant sterols (phytosterols). Among the phytoestrols found in pumpkin seeds, betasitosterol is one of the most important components which also have many medicinal properties. In this study, the effect of five levels of drought stress on seed oil production and its phytosterols was studied in three genotypes and Styriaca variety of pumpkin (Cucurbita pepo L.). Analysis of phytosterols using GC/MS showed that increasing drought stress had a negative effect on oil production from pumpkin ripe seeds, but oil phytosterols, especially betasitosterol, increased and this increase was higher in Styriaca than other genotypes. To confirm these results, the seeds were harvested 15-30 days after flowering and the expression of SQS, PP2A, SMT2, ERG26 and Cycloartenol synthase genes involved in the phytosterol biosynthesis pathway was investigated. The results indicated that, among the different levels of drought stress and genes studied, highest expression level was observed at the rainfed level and at that time, betasitosterol and stigmasterol pathway had the main activity in steroid biosynthesis pathway in pumpkin.
F. Heidari; F. Shekari; B. Andalibi; J. Saba
Abstract
In order to investigate the effects of growth regulators on yield and agronomical characteristics of saffron (Crocus sativus L.), an experiment was conducted in a randomized complete block design in the research greenhouse of Faculty of Agriculture, University of Zanjan. Experimental treatments included ...
Read More
In order to investigate the effects of growth regulators on yield and agronomical characteristics of saffron (Crocus sativus L.), an experiment was conducted in a randomized complete block design in the research greenhouse of Faculty of Agriculture, University of Zanjan. Experimental treatments included corms priming with gibberellic acid (GA) (250, 500 and 750μM), salicylic acid (SA) (700, 1400 and 2100μM), paclobutrazol (PBZ) (50, 100 and 150μM), chlormequat chloride (CCC) (500, 1000 and 1500 μM), hydropriming (HP) (distilled water), and control (treatment without any growth regulator). Among the treatments, the effect of GA was more pronounced than other growth regulators, so that the highest dry yield of flower and stigma was observed in GA treatment, especially at 500-μM level. CCC and PBZ caused the lowest flower and stigma yield and the highest amount of chlorophyll pigments compared to other treatments. In contrast, the use of GA and SA reduced the chlorophyll content. HP treatment did not show any significant difference with control. SA treatment increased safranal (perfume) and crocin (color) of the stigmas. The highest effect on picrocrocin (flavor) was obtained in CCC treatment.
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 ...
Read More
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.
