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We report three-dimensional Mott variable-range hopping (3D Mott-VRH) transport of Sr2IrO4 epitaxial thin films, with a transition to Efros-Shklovskii variable-range hopping (ES-VRH) with increased misfit strain or isovalent doping. We have observed that the characteristic temperature of 3D Mott-VRH transport decreases under increased misfit strain, implying that the density of states near the Fermi energy is reconstructed. With further increased misfit strain (or doping with Ca or Ba ions), a crossover from the 3D Mott-VRH to ES-VRH transport takes place due to increased carrier localization by disorder, opening a Coulomb gap by increasing the effective electron-correlation. The results of magnetoresistance measurements also confirm that the disorder caused by misfit strain or isovalent doping plays an important role in the electronic transport of these Sr2IrO4 thin films. Our experimental observations propose that subtle external stimuli such as structural modifications can modulate the electronic properties of the relativistic Mott insulator, suggesting an unprecedented pathway for electronic device applications. [ABSTRACT FROM AUTHOR]

The initial establishment of rangeland species, especially in arid and semi-arid areas, is a significant issue for the improvement and development of rangelands and increasing their yield. In order to investigate the effects of seed priming on changes in yield of the Astragalus brachyodontus, the present study was carried out in the greenhouse with factorial design. Three treatments of hydro-priming (distilled water), osmopriming (Polyethylene Glycol with two levels of -0.4 and -0.8 MPa) and priming hormone (gibberellic acid) as the first factor, and three levels of deficit irrigation stress (100% of field capacity, 75% of field capacity and 50% of field capacity) were considered as the second factor and three populations (Zanjan, Qom and Khalkhal) as the third factor with three replications. The results showed that seed priming, deficit irrigation stress, populations and their interactions had a significant effect (p≤0.01) on all investigated traits. The soil water reduction caused a significant decrease in seedling germination percentage, stem length and weight, however, the root length increased and the root weight first increased and then decreased intensively. The maximum yield of height (11.0267 cm), root length (30.6467 cm), stem weight (1.1700 g) and root weight (1.3664 g) was related to Zanjan population in normal irrigation. The treatment of -0.4 MPa osmopriming had the highest values in root length (33.1556 cm), stem weight (1.2144 g) and root weight (1.4800 g). Generally, according to the present research, -0.4 MPa osmo-priming and priming hormone with gibberellic acid were introduced as treatments to improve the Astragalus brachyodontus species performance in the greenhouse under the severe deficit irrigation stress condition. This result can be considered to improving the establishment and performance of this native valuable forage, in breeding programs and rangeland development, to improve its initial establishment in deficit irrigation conditions. [ABSTRACT FROM AUTHOR]

Gross primary production is one of the key factors for understanding growing grassland conditions and rangeland monitoring. The present study aims to introduce an improved index based on the primary GDP and NDVI vegetation index of MODIS. In this regard, field operations were carried out in May, simultaneously with the growth of vegetation in the Rasin basin of Kermanshah province. In each of the types, reference areas were determined, and six (100-meter) transects were deployed in each of the representative points. Along each transect, five plots were placed at a distance of 20 meters, and a total of 84 transects and 420 plots were used in the field. Information such as rangeland type and actual fresh forage (AFY, kg/ha) were determined in the Rasin basin. In general, three types were identified in the field. Modified primary GDP data were calculated and validated with the measured data in the Rasin basin of Kermanshah province. The results showed that, in type 1, with R² equal to 0.77 Ss index of gross primary production of NDVI as an improved index, in type 2, Ss index of primary production of NDVI with R² 0.73, in type 3, Ss index of gross primary production NDVI with R² equal to 0.71, and finally, for the whole rangeland type, Ss index of gross primary production of NDVI with R² equal to 0.51 was determined as the improved index. The results also showed that the modified primary GDP data is an acceptable indicator for monitoring grasslands. The accuracy of estimating rangeland production based on the Ss index of gross primary production of NDVI was 80%. The statistical results of comparing the estimated values with field observations indicate the acceptable accuracy of statistical models in estimating production. Also, since MODIS data is available twice a day, the improved index can supply the real need for rangeland monitoring on a regional scale. [ABSTRACT FROM AUTHOR]

Amino acids have diverse roles in plant metabolism, and recently amino acid based fertilizers have been used largely in crop production systems. Despite most of these new fertilizers are formulated for foliar application; however, morphophysiological responses of crops to amino acids application have applicationnot yet been well documented. In the present study, foliar application of glycine or glutamine in different concentrations of 0 (distilled water), 250, 500, 1000 mg·L-1, as well as a treatment of 250 mg·L-1 glycine + 250 mg·L-1 glutamine were evaluated on growth of sweet basil (Ocimum basilicum L.) plants. The results showed that foliar application of glycine or glutamine at 1000 mg·L1 showed no improvement in comparison with control for all traits except for leaf Lascorbic acid concentration that showed the highest value under these amino acids treatments. However, foliar application of these amino acids at 250 and particularly 500 mg·L-1 showed promising effect on sweet basil growth. Plant shoot fresh and dry weight, leaf area, leaf SPAD value, and leaf chlorophyll content were improved by foliar application of 500 mg·L-1 glycine or glutamine in comparison with control plants. Foliar application of amino acids increased leaf nitrogen (glutamine 250 and 500 mg·L-1), potassium (glycine 250 mg·L-1), magnesium (glutamine 250 or 500 mg·L-1, glycine 250 mg·L-1, glycine + glutamine; 250 + 250 mg·L-1), iron (glycine and glutamine at 500 mg·L-1 and glutamine at 250 mg·L-1), and zinc (glycine and glutamine at 250 or 500 mg·L-1), whereas the increase in leaf nutrients caused by other treatments was not significantly different from control plants. Leaf calcium concentration was not changed by amino acid treatments. The results indicate that foliar application of moderate to low concentrations of glutamine or glycine can improve sweet basil growth. [ABSTRACT FROM AUTHOR]

This study was conducted to demonstrate the growth behavior of Aeluropus lagopoides, Desmostachya bipinnata, Halocnemum strobilaceum, Alhagi graecorum and Atriplex leucoclada in the Zaminsang rangelands of Hormozgan province during 2007 to 2010. Determination of the production and consumption were done by the individuals in medium size. In each year, five medium individual of plant were selected for all months of growing and grazing season in exclosure area for measuring the production and the same number in the grazing range considered for measuring the production residue and from difference between them, the consumption was identified. Results indicated that different years and months had significant effect on production and consumption of the study species (p<0.05). According to the obtained data from the experiment indicated that, the average production of five perennials species was 125.8 kg dry forage per hectare. The highest production rate was obtained from Halocnemum strobilaceum and Desmostachya bipinnata in amount of 52.9% and 22.9% of total forage production, respectively. The average consumption of the species was 32.4 kg dry forage per hectare. The highest consumption rate was dedicated to Halocnemum strobilaceum and Alhagi graecorum, with amount of 41.8% and 30.1% of total forage consumption, respectively. The highest production rate was obtained from 2008 with 162.7 kg dry forage per hectare which was 1.8 times higher than low-production in 2009. The highest consumption rate for all species was 35.7 kg dry forage per hectare in 2009. The highest forage production and consumption were obtained in May in all species during the years. [ABSTRACT FROM AUTHOR]