Showing 6 results for Alavi
Mehran Alavi, Naser Karimi,
Volume 4, Issue 13 (Vol. 4, No. 13, 2015 2015)
Abstract
One of the major problems in recent years is the more dust storms occurrence in west regions of Iran in order to rising of the temperature and drought in the neighbored country (Iraq). In present investigation, effect of simulated dust storm on chlorophyll a fluorescence, chlorophyll content and phenol compounds surveyed in vitro in medicinal plan Thymus vulgaris. T. vulgaris is the aromatic medicinal plant with high economic value. This plant was stressed for a period of 2 months in the dust chamber as 0.5, 1 and 1.5 grams/m3 amount with four day intervals. After this period, results showed reverse relationship between dust amount and plant chlorophyll content and chlorophyll a fluorescence. Chlorophyll a and b content decreased with increase of the stress. Photosynthesis yield (ΔF/Fm´) had not significant reduction in first treatment (2%) and second treatment (21%), while it illustrated significant reduction in third treatment (28%). Electron transport rate (ETR) had significant decrease in T2 and T3 by 24% and 39% respectively. Also, there was increasing in treatments than to control in flavonoids and Anthocyanin. In the base of results in this investigation, high amount of the dust can has reduced effect on the photosynthesis performance.
Phd Masoud Khazaei, Phd Mohammad Galavi, Phd Mahdi Dahmardeh, Phd Seyd Mohsen Moosavi-Nik, Phd Gholamreza Zamani, Phd Nafiseh Mahdi-Nejad, Phd Zohreh Alizadeh,
Volume 7, Issue 27 (vol. 7, no. 27 2019)
Abstract
Water shortage is one of the most important limiting factors for crop production, that affected growth and yield by changing physiological conditions. This study was carried out to investigate effect of oxidative stress on antioxidant defense mechanism in Research greenhouses of Birjand University in 2014. A factorial arrangement of treatments based on randomized complete block design (Due to the lack of uniformity of light) with four replications was used .The studied factors were drought stress with three levels including 100, 75 and 50 percent of plant water requirement (non-stress, moderate and severe stress respectively) and millet genotype with three levels (including Bastan, promising lines KFM5 and KFM20).. Malondialdehyde, electrolyte leakage and membrane stability was measured in 30 and 45 days after stress and yield in maturity. Antioxidant activity (including SOD, CAT and APX) was measured in 30 days after stress. The results showed that antioxidant activity increased as intensity of drought stress increased in all three genotypes. Bastan had the highest antioxidant activity under sever stress that showed it had best antioxidant defense system and better scavenge reactive oxygen species than another genotypes. The malondialdehyde content (MDA) was low in Bastan compared to other genotypes and was less affected by increasing drought stress that showed this genotype was less affected by oxidative stress. Seed yield decreased as intensity of drought stress increased in all three genotypes and had negative correlation with antioxidant activity.
Miss Elham Mohamadi, Dr. Vida Chalavi, Dr. Hossein Moradi,
Volume 8, Issue 30 (vol. 8, no. 30 2019)
Abstract
The aim of present study was to investigate the effect of explants types, in light and darkness condition on propagation of lateral plantlets and also to investigate the effect of type and concentrations of carbohydrates on the regeneration of Catasetum orchid plantlets in two experiments. First experiment for propagation of lateral plantlets was done with two types of explants, shoot tips and root tips, in combination with different lighting conditions (light and darkness) in completely randomized design with 5 replications. According to obtained results, the production of leaves, roots, lateral plantlets and the intensity of explant necrosis were affected by explants types and environmental conditions of light and darkness treatments and were statistically significant at (p ≤ 0.01 & 0.05). The highest mean number of leaves (21.4), roots (5) were from shoot tip explants in light and the highest mean number of lateral plantlets (17.8) observed in root explants in darkness. In second experiment, the effect of different concentrations of sucrose and mannitol were investigated on the regeneration of Catasetum orchid plantlets. Experimental treatments were three levels of sucrose, 20, 30, 40 g/l, two levels of mannitol, 10.08 and 22 g/l in combination with 20 g/l of sucrose and mannitol alone at 10.08 g/l concentration. The highest mean number of formed lateral plantlets from each explant were 10.48 which were obtained at 30 g/l sucrose concentration. For production and growth of protocorm like body, all mannitol concentrations were better than sucrose and the highest protocorm like body mean number (1.54) were produced in 10.08 g/l mannitol concentration. In general conclusion, the highest lateral plantlets regeneration occurred from root explants in darkness treatment by using sucrose.
Peyman Davami, Mojtaba Alavifazel, Shahram Lak, Davood Habibi, Afshin Mozaffari,
Volume 10, Issue 41 (vol. 10, no. 41 2021)
Abstract
This experiment was conducted as factorial split plot in randomized complete block design with three replications for two years (2015-2016 and 2016-2017) in Karaj region. Irrigation includes regular irrigation (irrigation after 80 mm evaporation from Class A evaporation pan) and irrigation-off from the silique stage onwards in the main plots and planting date including the 5th of October and the 5th of November and rapeseed cultivars including Tasillo, Elvis, Neptune And okapi (control) were factorially divided into subplots.Based on the results, the highest amount of chlorophyll in both planting dates (October 5 and November 5) with values of 1.59 and 1.88 mg / g fresh leaf weight and in normal irrigation conditions were assigned to Elvis cultivar. . The results showed that irrigation-off increased leaf proline and ion leakage of the studied cultivars while the relative leaf water content decreased. Elvis cultivar had the highest grain yield in earlier planting date (October 5) and in normal irrigation with an average of 3346.67 kg / ha.The highest percentage and yield of oil were 45% and 1349 kg of Elvis cultivar in the first year, respectively, in normal irrigation conditions, and the lowest amount of these traits was obtained from Tasilo cultivar in the irrigation-off on the 5th of October. The highest amounts of linolenic acid, static acid, rosaric acid and grain glucosinolate were 5.9, 3.36, 0.34, 32.78%, respectively in irrigation-off conditions and later planting date (November 25). Elvis cultivar was superior to other cultivars in terms of chlorophyll content, higher percentage of oil and fatty acids and less grain glucosinolate, which are considered as important and useful criteria for tolerance to dehydration stress of rapeseed.
S. Soghra Akbarzade, Mahnaz Karimi, Vida Chalavi,
Volume 12, Issue 56 (vol. 12, no. 56 2023)
Abstract
Zinnia (Zinnia elegans) is an annual and widely used ornamental plant. Considering the importance of the growing medium in the production of ornamental plants, this study was conducted to investigate the effect of wood waste compost and humic acid on the morphological and physiological characteristics of Zinnia. Wood waste compost (0, 25, 50, 75 and 100% instead of peat moss in the control growth medium) along with humic acid (0, 250 and 500 mg L-1) were used. Peat moss, perlite and garden soil (1:1:1) were used as the control substrate. In this research, plant height, number and surface of leaves, fresh and dry weight of plants, fresh and dry weight of roots, flower diameter, chlorophyll, nitrogen, phosphorus and potassium of leaves were investigated. According to the obtained results, the highest amount of plant leaf area was obtained in 50% compost with 500 mg L-1 of humic acid and the highest number of leaves were obtained in 75% compost with 500 mg L-1 of humic acid. The largest flower diameter (76.2 mm) was recorded in 100% compost. The amount of chlorophyll a and b in 100% compost combined with humic acid of 500 mg L-1 was at the highest level. The highest amount of nitrogen (0.75%) was recorded in 100% compost. The application of humic acid 250 mg L-1 caused a significant increase in leaf potassium. In general, the results showed that the application of compost in amounts of 50 to 100 percent and humic acid of 250 and 500 mg L-1 was effective on flower diameter, plant height, number of leaves, chlorophyll, and the increase of nitrogen and potassium elements in Zinnia leaves.
Fatemeh Kheiri, Mahnaz Karimi, Vida Chalavi, Zeinab Roein,
Volume 13, Issue 59 (vol. 13, no. 59 2024)
Abstract
It is important to reduce the height of ornamental plants in order to produce short plants. One of the height control methods is the use of growth inhibitors. In order to investigate the effect of sumagic (uniconazole) on the growth and biochemical characteristics of daffodil, a factorial experiment was conducted in a completely randomized design with three replications. The first factor was sumagic (5 and 10 mg L-1, as foliar spraying and bulb immersion application), and the second factor was two genotypes of narcissus native to Iran (Shahla Shomal and Porpar Shomal). According to the results of the experiment, the highest number of flowers was obtained in the Porpar genotype and in the treatment of sumagic 5 and 10 mg L-1. The height of the flowering stem was the lowest in the treatment of sumagic 10 mg L-1 in immersion application, which showed a decrease of 37.64% compared to the control. Also, the lowest leaf length and the highest root length were observed in the treatment of sumagic 10 mg L-1 in immersion application. The highest amount of chlorophyll was obtained in the treatment of 5 mg L-1 sumagic immersion, and the highest amount of carotenoid was obtained in the Porpar genotype with 10 mg L-1 foliage spraying. The phenol content was at the maximum in the control and was not significantly different from the 10 mg L-1 sumagic. The highest percentage of nitrogen was obtained in sumagic at 10 mg L-1 immersion. The highest percentage of phosphorus was obtained with the application of 5 mg L-1 sumagic. The results of the present study showed that the use of sumagic can reduce the height of the daffodil plant and improve its physiological and biochemical characteristics.
