To evaluate morphological and biochemical changes of almond (Prunus dulcis Mill.) under salt stress conditions and determine relationship among accumulation of Na and Cl with these traits، an experiment was conducted based on completely randomized design with four treatments including 0 (control)، 25، 50 and 75 mM of pure sodium chloride and three replications from 2010 to 2012. The seed of healthy almond genotypes grown in natural saline areas of East-Azerbaijan province were used as the experimental material in this study. Salt treatments were influenced during eight weeks following the growth and appearance of 15 – 20 leaves on each seedling. The results showed that the threshold of marginal leaf scorch symptoms was in relation with an accumulation of 9–11 mg/g DW Na. Also، mean of free proline content increased from 37. 7 to 117. 9 µmol. g-1 FW linearly and significantly in parallel with the accumulation of Na and Cl in the leaves. Under same conditions، catalase and ascorbate-peroxidase activity increased significantly; however peroxidase activity increased up to 50 mM salinity but decreased subsequently at higher levels of salt.

The identification of the characteristics of native halophytic species is very important for their practical application. The present study was carried out to identify the halophytic species of a desert and highly saline region around the city of Khosf, southern Khorasan Province, and to detect their general tolerance mechanisms (i.e. salt exclusion or inclusion). Sodium accumulation in the roots and shoots of seven species, including Launaea arborescens, Peganum harmala, Pteropyrum olivieri, Artemisia santolina, Zygophyllum eurypterum Boiss, Aerva javanica, Pulicaria gnaphalode, and their rhizosphere soil were determined. The bioconcentration of sodium from soil to roots (BCF), its translocation from roots to shoots (TF), and its accumulation in the shoots (AF) were then calculated. Results showed that the soil of the studied area was clay loam with a high EC of 65 ds/m, indicating its high salinity level. According to the values of sodium adsorption ratio (SAR) and the exchangeable sodium percentage (ESP) and regarding EC, the soil of studied region can be regarded as a saline-sodic soil. The value of TF in some species was higher than 1. However, none of the species had BCF and AF greater than 1, thus, none of them could be considered to be salt accumulator. Instead, it could be assumed that all of the studied species were salt, or at least, sodium excluders.

The first step in the implementation of natural resource improvement, restoration or exploitation programs is to know the vegetation of different regions of the country. There is a mutual relationship between soil and vegetation, and soil is the most important factor in plant growth and geographical distribution. Fars province has many pasture and forest habitats and can be used as a research center to select and introduce appropriate plant species that are compatible with harsh ecological conditions and soil characteristics of the country. The aim of this research was to investigate the effect of Zygophyllum euryptrum plant on some chemical characteristics of its habitat soils in Abadeh, Sarvestan and Khonj. This research was carried out using a factorial design in the dimensions of 2 × 2 × 3 (three zones, two depths and two distances) and in the form of a completely randomized design with three replications. Soil samples were taken from two profiles within canopy and outside the canopy, from two depths of 0-20 and 20-40 cm in the three indicated zones. The chemical properties of the soil have been measured. The results showed that there was a significant difference in pH, EC, concentration of soluble anions (chlorine, bicarbonate and sulfate), SAR, OM and CEC between different areas, depths and distances. There was a significant difference in the area and depth of CCE. There was no significant difference in the distance. The growth of Zygophyllum eurypterum plant has turned the soil of its habitat into saline soil by increasing the EC of the surface soil under the canopy. Despite the SAR increase under the canopy, the obtained values didn’t show any threat related to sodium ion hazards. Zygophyllum eurypterum showed high sodium accumulation factor in the shoot (AF). According to this research, the important role of Zygophyllum eurypterum in surface characteristics of soil development is determined.

Salinity is a limiting factor in agricultural production that inflicts great damages on agricultural products. In order to decrease or stop salinity stress, numerous methods are proposed by different researchers. One of the methods to reduce the damages of salinity stress is cultivating tolerant plants to salinity. In this research, resistance of three radish cultivars to salinity stress was investigated, from physiological points of view, and the best resistant cultivar was introduced. This factorial experiment was carried out in Research Greenhouse of Ferdowsi University of Mashhad, Iran, based on complete randomized design, with three replications. Treatments included three commercial cultivars of radish (Cherry belle, Sparkler and Scarlett Cincinnati) as the first factor and four levels of salinity (control, 33, 66 and 99 mM NaCl) as the second factor. Salinity levels, as soluble form in irrigation water, were applied at the four-leaf stage of the plants. Results showed that salinity decreased the amount of soluble sugars and potassium content of aerial parts and tubers, and also increased stomatal conductance, anthocyanin content of tubers and sodium content of aerial parts and tubers. The highest tolerance of different radish cultivars to salinity stress was observed at 66 mM salinity level and the 33 mM salinity level had no significant difference, compared to control, in most physiological characteristics. Under salinity stress conditions, sodium accumulation in aerial parts was more than tubers. The highest amount of tuber anthocyanin was measured at 66 mM salinity level in Scarlett Cincinnati cultivar. Among the radish cultivars, the highest salinity tolerance and salt accumulation was obtained from Scarlett Cincinnati cultivar. Considering that the apparent shape of this cultivar (stretched appearance with red color) is very different from Cherry belle and Sparkler cultivars, and more water is stored in its tissues, thus, this trait has caused high resistance to salinity stress.

Salinity is a very important factor in restricting the plant growth. The elements prevent the accumulation of sodium in cells،can also decrease harmful effects of salinity. One of these elements is potassium which different salts indicated different responses in decreasing the unsuitable effects of salinity. In this study immaturate embryos of ‘Va-alfajr’ cultivar were cultured on MS medium having different concentration of Kin and 2،4D hormones. Protein content and proline amino acid of the calli were measured. Results showed that optimal treatment for callus formation was MS medium containing Kin= 0 and 2،4D= 2mg/L. This investigation showed that increasing NaCl and KCl in medium، callus index decreases. Results showed that with increasing NaCl and KCl in the medium total protein decreases while the amount of proline increases.

In this paper, an algorithm base on Monte Carlo simulation for pileup effect in gamma spectrum of a detection system is presented whose its code was written in FORTRAN language. The code can be run in paralayzable and nonparalazable mode to obtain the pileup distortion and value of pulses pileup for any detection system. The result show, that the computed spectrum of 137Cs is in good agreement with the experimental spectrum in NaI(Tl) detector. The free of pileup free spectrum and sub-spectra with different degrees of pulses of pileup are calculated. Also, we can apply it to different sources and detectors for pileup correction.

This paper presents the study on the effect of detector type in estimating gamma rays buildup factor. In this regard, the flux buildup factors of gamma rays emitted by an isotropic point 60Co source in mean energy 1.253 MeV was evaluated after passing through the Pb, W, Zn, and Ti sample in thickness of 1-5 cm by MCNPX. Four common detector types in simulation of measurement was defined to estimate the gamma rays flux: an empty cylinder, Geiger-Muller counter, NaI(Tl) scintillator, and point detector. Due to the deep penetration condition, weight windows varience reduction technique is applied to achieve more accuracy and less computer run time simultaneously. The present work confirm the buildup factor dependence on atomic number of materials, and detector type. The results show that the value of buildup factors was varied from 1 to 4 in different states. However, the variation of buildup factors follow almost similar trend in different detector types. According to the results, applying point detector in simulation is suggested which lead to increased accuracy of simulation and decreased computer run time.

Thyme (Thymus vulgaris L.) is an important medicinal plant in perfume and medicine industry. In this research، we assessed effects of salinity stress on morphologic، physiologic، and chemical characteristics of (Thymus vulgaris L.). In this research we used complete randomized blocks with 6 treatments and 4 replications. Irrigational levels of water salinity levels were (0، 60، 90، 120، 150 mMolL-1) sodium Chloride The results showed that salinity stress had significant effects on growth parameters، prolin content and thymol percent. With increasing irrigational levels of water salinity، plant height، number stem side، dry weight of plant، thymol percent decreased and root mass، dry weights of root، length and prolin concentration increased. Highest levels of topsoil parts of plant، root and prolin content were produced consequently without salinity stress، high salinity stress (120 mMolL-1) and very high salinity stress (150mMolL-1). Highest levels thymol percent in control and with increase salinity decreased.