M. Eskandari
Abstract
Environmental stresses, particularly drought stress, are considered as one of the major obstacles in the production of horticultural crops in many parts of the world, especially in arid and semiarid regions like Iran. Brassinosteroids are of plant steroidal compounds with broad biological activities ...
Read More
Environmental stresses, particularly drought stress, are considered as one of the major obstacles in the production of horticultural crops in many parts of the world, especially in arid and semiarid regions like Iran. Brassinosteroids are of plant steroidal compounds with broad biological activities that are able to increase plant performance through changes in plant metabolism and protectecting them against environmental stresses especially drough stress. In a greenhouse study, the impact of three levels of irrigation at field capacity (FC), mild stress (FC2/3) and severe stress (FC1/3) and four concentrations of plant growth regulators of Article 28-Homobrassinolid including zero, 10-10 M, 10-8 M and 10-6 M were investigated on some traits of Satureja Bachtiarica Bunge. The results showed that reducing irrigation had a significant effect on the reduction of growth parameters, including root length, root dry weight, stem diameter, branch number, plant height, shoot yield and total yield. Concentration of 10-8 M 28-Homobrassinolid significantly increased root dry weight, stem diameter, branch number, plant height, and total yield. Oil percentage showed a significant increase at 1% level of probability by reducing irrigation as it increased from 0.36% in full irrigation upto 0.87% in severe stress and use of 10-8 M hormone. Generally, our results showed that the use of 28-Homobrassinolid could increase dry matter yield through stimulating growth parameters and it was considered as as a good strategy to deal with water stress conditions.
Z. Aslani; A. Hassani; M. Rasooli Sadaghiyani; F. Sefidkon; M. Barin
Abstract
To study the influence of arbuscular mycorrhizal (AM) fungi inoculation and drought stress on growth, chlorophyll content and phosphorus uptake of basil (Ocimum basilicum L.), a pot experiment was conducted using a factorial based on randomized complete blocks design with four replications. The factors ...
Read More
To study the influence of arbuscular mycorrhizal (AM) fungi inoculation and drought stress on growth, chlorophyll content and phosphorus uptake of basil (Ocimum basilicum L.), a pot experiment was conducted using a factorial based on randomized complete blocks design with four replications. The factors were mycorrhizal inoculation (non-inoculated and inoculated with Glomus mosseae T.H. Nicolson & Gerd. and Glomus intraradices N.C. Schenck & G.S. Sm) and three irrigation regimes (irrigation intervals were every 4, 8 and 12 days). The results showed that drought stress had significant effects on evaluated characteristics. As with decrease of the soil water content, plant height, stem diameter, number and area of leaves, number of axillary shoot, root dry weight, fresh and dry herb yield, chlorophyll content, P concentration in leaves and root colonization decreased. Also, AM fungi inoculation had significant effects on growth parameters and P uptake. Plants inoculated with AM fungi had higher growth, yield and P uptake than non-inoculated plants under droughtstress and non-stress conditions. G. mosseae was more effective than G. intraradices in alleviation of drought stress. It could be concluded that AM fungi are able to enhance the growth and yield of basil under drought stress condition through enhancing P uptake.
M.K. Soltani Gerdfaramarzi; H. Omidi; H. Habibi; M.H. Lebaschy; A. Zarezadeh
Abstract
For assigning of drought stress and glycine betaine effects on yield, yield components and essential oil in German chamomile (Matricaria chamomilla L.) genotypes,a field experiment was conducted in the Field of the Agricultural Educational Center of Yazd in 2008-2009 Cropping season. The experiment was ...
Read More
For assigning of drought stress and glycine betaine effects on yield, yield components and essential oil in German chamomile (Matricaria chamomilla L.) genotypes,a field experiment was conducted in the Field of the Agricultural Educational Center of Yazd in 2008-2009 Cropping season. The experiment was established as a randomized complete blocks design using a split plot factorial with 4 replication arrangement and three factors including drought stress at three levels (irrigation at 60, 120, 180 mm evaporation pan class A) in main plots and factorial combination of Glycine betaine (no foliar application, 2, 4 kg/ha foliar application) and cultivars (Isfahan mass and Hungary breed seed) in subplot. Plant height, plant flower number, dry flower yield and relative water content were measured. Results showed there are indirect relations between drought stresses and plant height, plant flower number, dry flower yield and relative water content. Also results showed that 2 kg/ha foliar application of Glycine betaine was better than others and there are no significant different between cultivars.
Zh. Asadi Kavan; M. Ghorbanli; A. Sateei
Abstract
Drought stress provokes ROS production in plant cell chloroplasts and subsequently causes lipid membrane peroxidation and damage. Pimpinella anisum L. is one of the aromatic herbal plants which has great export value. The aim of this study was applying exogenous ascorbate in order to control oxidative ...
Read More
Drought stress provokes ROS production in plant cell chloroplasts and subsequently causes lipid membrane peroxidation and damage. Pimpinella anisum L. is one of the aromatic herbal plants which has great export value. The aim of this study was applying exogenous ascorbate in order to control oxidative stress during drought tolerance. Changes of pigment content of leaves, total phenol compounds, malonedialdehyde (MDA) content were measured. In a pot study, drought stress introduced to treatments with 3 replicates based on 3 levels of field capacity (100, 60 and 25%) and ascorbate (1.4 mM) sprayed on them. Chlorophyll content and chlorophyll a/b ratio decreased with increasing in stress levels, while flavonoids and anthocyanins increased. Carotene and xanthophyll increased only in moderate stress level due to drought. Exogenous ascorbate increased chlorophylls and carotenoid content but decreased flavonoid and anthocyanin contents and had great effect on increasing phenol compound in all stress levels. MDA content remained relatively constant, but increased significantly in severe stress levels. Applying exogenous ascorbate led to decreasing metabolite. According to the results exogenous ascorbate could increase the ability of Pimpinella anisum in response to drought stress with different mechanisms and had protective effect against lipid peroxidation due to drought stress.
A. Ghani; M. Azizi; A. Tehranifar
Abstract
Achillea (Yarrow) is one of the most important genera of the Asteraceae family and different species grow wild in different parts of Iran. These species have ornamental and medicinal potential for use in drought area. The aim of this study was evaluating the effect of drought stress induce by Poly Ethylene ...
Read More
Achillea (Yarrow) is one of the most important genera of the Asteraceae family and different species grow wild in different parts of Iran. These species have ornamental and medicinal potential for use in drought area. The aim of this study was evaluating the effect of drought stress induce by Poly Ethylene Glycol 6000 (PEG) on germination percentage and rate of Achillea species. An experiment in randomized complete block design (RCBD) with two factors in three replications was conducted. The first factor included 5 drought level (0, -5, -7, -9 and -20 bar that zero bar as control) and second factor included 6 species of Achillea (A. eriophora, A. millefolium, A. filipendula, A. nobilis, A. wilhelmsii and A. biebersteinii). The seed were collected from Shiraz, Mashhad and Karaj area. According to the results of statistical analysis, different levels of drought stress and type of species had significant effect (p<0.01) on measured characteristics (germination percentage, germination rate and radicle length). In this species radicle length affected by drought stress less than other traits and germination percentage was the best trait for drought stress evaluation. Finally, A. millefolium and A. eriophora have the highest drought tolerance and the lowest drought tolerance belongs to A. biebesteinii and A. nobilis. The A. wilhelmsii and A. filipendula have relative drought tolerance in germination stage.
B. Abbaszadeh; E. Sharifi Ashourabadi; M.H. Lebaschi; M. Naderi hajibagher Kandy; F. Moghadami
Abstract
In this research effect of drought stress on physiological characteristics of balm (Melissa officinalis L.) was performed under field condition in Karaj, Iran in 2005. Experiment was conducted using randomized complete block design with 4 replications. Treatment included T1 (non stress), T2 (80%FC), ...
Read More
In this research effect of drought stress on physiological characteristics of balm (Melissa officinalis L.) was performed under field condition in Karaj, Iran in 2005. Experiment was conducted using randomized complete block design with 4 replications. Treatment included T1 (non stress), T2 (80%FC), T3 (60%FC), T4 (40%FC) and T5 (20%FC). Effect of drought stress on chlorophyll a, chlorophyll b, proline, soluble sugars, relative water contents, percentage and yield of essential oil were significant (α=0.001). Effect of drought stress on total chlorophyll was significant (α=0.005). Comparison of treatment means showed that highest chlorophyll a (1.921mg/l), chlorophyll b (1.197mg/l), total chlorophyll (2/283mg/l) were related to T1 (control), T5 (20%FC) and T1 (control), respectively. Highest accumulation of proline with 2.545 mg/l mean was related to T3 (60%FC). Maximum relative water content with 93.369 mean percentage related to T1 (control). It could be concluded that plant accumulation of proline and solublesugars increased tolerance and showed that moderate drought stress is beneficial for balm production.
S.F. Afzali; H. Shariatmadari; M.A. Hajabbasi; F. Moatar
Volume 23, Issue 3 , November 2007, , Pages 382-390
Abstract
Flavonoids are polyphenolic compounds with strong antioxidant effects. Chamomile (Matricaria chamomilla L.) is used for a variety of herbal remedies, containing classes of biologically active compounds including flavonoids and essential oil. There have also been many reports, showing that flavonol-O-glycosides ...
Read More
Flavonoids are polyphenolic compounds with strong antioxidant effects. Chamomile (Matricaria chamomilla L.) is used for a variety of herbal remedies, containing classes of biologically active compounds including flavonoids and essential oil. There have also been many reports, showing that flavonol-O-glycosides are quantitatively the most abundant flavonoids found in chamomile flowers. Tolerance of this plant on saline and drought conditions has not been well studied and documented. Therefore a greenhouse experiment was conducted using complete randomized design with four replications in order to evaluate the effects of salinity and drought stress on flower dry weight and falavonoids component of chamomile. Hydroponic solutions are used for salinity experiment at five levels of NaCl concentrations (0, 40, 80, 120, 190 mM). In order to examine drought stress, we used gravitational method and four treatments (FC soil moisture content, and 75, 90, 95 depletion percent of soil AWC) in a pot experiment. Then the flower dry weight and their flavonol-O-glycosides were measured. The Results showed that both salinity and drought reduced flower dry weight and flavonoids concentration, but drought reduction effects were more than salinity. Flowers dry weight significantly increased with increasing NaCl concentration up to 40 mM while decreased at higher salinity levels. There were no significant differences between salinity treatments up to 80 mM NaCl for flavonol-O-glycosides concentration. Regarding the dry flower yield, the highest content of flavonol-O-glycosides was observed in 40 mM NaCl treatments. Flower dry weight and Flavonol- O- glycosides decreased as drought levels increased.
M.R. Ardakani; B. Abbaszadeh; E. Sharifi Ashourabadi; M.H. Lebaschi; F. Packnejad
Volume 23, Issue 2 , August 2007, , Pages 251-261
Abstract
In order to study drought stress effect on quantitative and qualitative features of balm (Melissa officinalis L.) a research was conducted under field condition in Karaj, Iran in 2005. Experiment was conducted using Randomized Complete Block Design with 4 replications. Treatment included T1 (non stress), ...
Read More
In order to study drought stress effect on quantitative and qualitative features of balm (Melissa officinalis L.) a research was conducted under field condition in Karaj, Iran in 2005. Experiment was conducted using Randomized Complete Block Design with 4 replications. Treatment included T1 (non stress), T2 (80%FC), T3 (60%FC), T4 (40%FC) and T5 (20%FC). Effect of drought stress on shoot yield, essential oil yield, percentage of essential oil, leaf and stem yield, height, tiller number, length and width of leaf, stem diameter and internodes was significant (α=0.001). Effect of drought stress on number of lateral stem was not significant. Comparison of treatment means showed that highest shoot yield was related to T1 (non Stress) (6469kg/ha), highest essential oil (12.970 kg/ha) and highest essential oil percentage (0.3012%) was related to T4 (40%FC) and T5 (20%FC), respectively. Highest height (65.32 cm), leaf length (6.27 cm) and width (4.58 cm) were related to T1 (non stress). Highest stem diameter was related to T5 (20%FC). It could be concluded that moderate drought stress is beneficial for balm essential oil.
F. Safikhani; H. Heydari sharifabad; A. Syadat; E. Sharifi Ashorabadi; S.M. Syednedjad; B. Abbaszadeh
Volume 23, Issue 1 , May 2007, , Pages 86-99
Abstract
In order to investigation effect of drought stress essential oil percent and yield and physiological characteristics of medicinal plant Deracocephalum moldavica L. under greenhouse. This research performed in 2004-2005 at research institute of forests and rangelands. Experiment was carried out in a split ...
Read More
In order to investigation effect of drought stress essential oil percent and yield and physiological characteristics of medicinal plant Deracocephalum moldavica L. under greenhouse. This research performed in 2004-2005 at research institute of forests and rangelands. Experiment was carried out in a split plot under randomize complete block design with four replications. Main factors were contains of three populations of Deracocephalum moldavica L. that collected from Tehran, Esfahan and Fars provinces. Subplots were contains three level of drought stress 100% Fc, 60% Fc and 40% Fc. The results showed that effect of different populations not significant. The results showed that effect of drought stress on essence yield, amount of solution carbohydrates, amount of a, b and total chlorophyll at two years were significant. So effect of drought stress on proline in second year was significant. The results analysis variation of two years showed that effect of year on essential oil percent and proline amount was significant (α=1%). Comparison mean of treatments showed that at first year highest of essence yield, solution carbohydrate and chlorophyll respectively related to 60%, 40% and 100% of field capacity treatments. At second year highest proline amount, solution carbohydrate and chlorophyll respectively related to 40%, 40% and 100% of field capacity treatments. Comparison mean treatments of plant populations and different levels of drought stress showed that at first year highest of essential oil percent related to Esfahan seed*60% humidity of field capacity. Highest chlorophyll relate to 100% humidity of field capacity in three ecotypes. At second year highest solution carbohydrate and chlorophyll respectively related to 40% and 100% of field capacity in three populations.
