Mommad Hadi Rad; Mehdi Soltani; Mostafa Zare Mehrjerdi; Mahdieh Tajamolian
Volume 21, Issue 4 , March 2015, , Pages 620-630
Abstract
Despite the high resistance of black saxual (Haloxylon aphyllum) to environmental stress such as drought, there is the possibility of further resistance in different populations. This experiment was carried out to determine the drought tolerance in seven populations of black saxual(Yazd, Esfahan, Semnan, ...
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Despite the high resistance of black saxual (Haloxylon aphyllum) to environmental stress such as drought, there is the possibility of further resistance in different populations. This experiment was carried out to determine the drought tolerance in seven populations of black saxual(Yazd, Esfahan, Semnan, South Khorasan, Sistan va Blochestan, Kerman) under three moisture treatments (100%, 50% and 25% of field capacity) using small weighing lysimeters. The study was conducted in Yazd Shahid Sadoqi Research Station during 2010-2012 using a randomized complete block design with three replications. The effects of soil moisture treatments were studied on morphological traits such as shoot dry weight, root dry weight, root to shoot ratio and physiological traits such as leaf and root osmotic potential, relative water content, water use efficiency, total chlorophyll, chlorophyll a, chlorophyll b, Na+ and K+ accumulation in roots and shoots. According to the results, no significant differences were recorded among the populations in response to the moisture treatments except chlorophyll content (P<0.05). The effect of moisture treatments on water use efficiency and physiological traits such as leaf osmotic potential, relative water content of leaves, total chlorophyll, chlorophyll a, chlorophyll b and Na+ in the root were significant (P<0.01). In addition, the effect of moisture treatments on leaf potassium was significant (P<0.05). Drought stress had no significant effect on other traits, including root osmotic potential, leaf Na+ and root K+. Effects of drought stress on morphological traits including shoot dry weight, root dry weight, total dry weight, and root to shoot ratio were significant (P<0.001). The interaction effects of population and moisture treatments on morphological characteristics were not significant.
Mahdiye Tajamoliyan; Mohammad Hasan Iran nezhad parizi; Hosein Maleki Nezhad; Mohammad Hadi Rad; Hamid Sodaii Zadeh
Volume 20, Issue 3 , November 2013, , Pages 540-548
Mohammad ali Meshkat; Mohammad hadi Rad; Seyed Reza Hoseini
Volume 14, Issue 4 , February 2008, , Pages 447-454
Abstract
Higher evaporation compared to precipitation in arid zones causes upward movement of soil water and consequently salts will be accumulated in root zone. Since Salt moves with water flow, salt distribution will fallow a pattern similar to soil water distribution. The amount of applied water or leaching ...
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Higher evaporation compared to precipitation in arid zones causes upward movement of soil water and consequently salts will be accumulated in root zone. Since Salt moves with water flow, salt distribution will fallow a pattern similar to soil water distribution. The amount of applied water or leaching fraction is one of the most important and effective factors on salt movement and distribution in soil. This research was established at Yazd Desert Research Station in weighting lysimeters. Salt profile in soils of three hrrhgation treatments : FC, 1/3 FC and no irrigation were plotted and compared with each others for three times (t1 , t2 and t3) in this research. In addition soil moisture was also controlled in different ways. The experhment was done in a completely randomized design and Duncan's test was used for comparison of means. Results indicated that soil salinity increased from top soil to deeper layers and this feauture was more significant in fully irrigated treatments specially at the latest times (t2 and t3). Total accumulated salt was also more at more irrigated treatments. High salinity of water and inadequate of leaching ,were the most important factors which led to salt accumulation in the deep layers of fully irrigated lysimeters.