Plant selection method for urban landscapes of semi-arid cities (a case study of Tehran)

Choosing appropriate plants for urban landscapes is vital to avoid potential financial and environmental losses that may occur if all selection parameters are not taken into account. A methodology has been developed to assist landscape architects, planting designers, and urban horticulturists in the plant selection process. Tehran has been picked as a case study due to its arid and semi-arid climate which poses more challenges in front of an expert. After grouping plants, selection parameters have been defined for each plant group. Plant species were comparatively graded for each parameter by a group of eight specialists. Analytical hierarchy process (AHP) technique and hierarchical cluster analysis have been utilized to find the most adaptable plant species for the area according to the main selection parameters of zone tolerance, urban conditions, esthetics, maintenance, growth characteristics, and specific features. Several new plants were ranked high in the final tables suggesting that the urban landscape of Tehran has a great potential to become more attractive, less allergic, and less costly, as well as consuming less water. Before introducing new plants to the urban environment, they should be experimented on in small numbers for several years to confirm that they will not change the ecology of the whole region through invasion or posing a threat to any local plant species.     

Molecular characterization of a 13-amino acid deletion in VP1 (1D) protein and novel amino acid substitutions in 3D polymerase protein of foot and mouth disease virus subtype A/Iran87

The nucleotide sequence of the VP1 (1D) and partial 3D polymerase (3D^pol) coding regions of the foot and mouth disease virus (FMDV) vaccine strain A/Iran87, a highly passaged isolate (~150 passages), was determined and aligned with previously published FMDV serotype A sequences. Overall analysis of the amino acid substitutions revealed that the partial 3D^pol coding region contained four amino acid alterations. Amino acid sequence comparison of the VP1 coding region of the field isolates revealed deletions in the highly passaged Iranian isolate (A/Iran87). The prominent G-H loop of the FMDV VP1 protein contains the conserved arginine-glycine-aspartic acid (RGD) tripeptide, which is a well-known ligand for a specific cell surface integrin. Despite losing the RGD sequence of the VP1 protein and an Asp₂₆→Glu substitution in a beta sheet located within a small groove of the 3D^pol protein, the virus grew in BHK 21 suspension cell cultures. Since this strain has been used as a vaccine strain, it may be inferred that the RGD deletion has no critical role in virus attachment to the cell during the initiation of infection. It is probable that this FMDV subtype can utilize other pathways for cell attachment.     

Effects of foliar spray of nano-particles of FeSO4 on the growth and ion content of sunflower under saline condition

This study investigated the effects of foliar spray of normal and nano-particles of iron sulfate (FeSO₄) on the response of sunflower cultivars to salinity. Treatments included five cultivars (Alstar, Olsion, Yourflor, Hysun36 and Hysun33), two salinity levels (0 and 100 mM sodium chloride (NaCl)), and three levels of fertilizer application. Fertilizer treatments were the foliar application of normal and nano-particles of FeSO₄. Foliar application of FeSO₄ in either form increased leaf area, shoot dry weight, net carbon dioxide (CO₂) assimilation rate (A), sub-stomatal CO₂ concentration (Ci), chlorophyll content, Fv/Fm and iron (Fe) content and decreased sodium (Na) content in leaves. The extent of increase in chlorophyll a content by foliar spray of FeSO₄ nano-particles was significantly greater than normal form. The results showed that the FeSO₄ nano-particles increased biomass production of sunflower plants greater in comparison with normal form, although no significant difference was found between two forms.     

Genetic diversity analysis and character associations in black cumin (Nigella sativa L.) based on agro-morphological and phytochemical traits

Black cumin (Nigella sativa L.) is one of the important medicinal plants that used in food and pharmaceutical industries. In the present study, 32 Iran endemic black cumin genotypes were evaluated through randomized complete block design with three replications in 2016 and 2017 growing seasons to determine the extent of genetic diversity and character associations for agro-morphological and phytochemical traits. Results showed the significant differences between genotypes for all traits studied. Clustering analysis using agro-morphological and phytochemical traits grouped genotypes into the two distinct groups. The values of percentage of essential oil and fatty oil content varied from 0.65 to 0.1.36% and 25.30% to 35.02% between genotypes, respectively. The highest seed yield and fatty oil yield obtained for Arak genotype. GC and GC/MS analyses of essential oil and fatty oil compositions of the Arak genotype revealed that p-cymene and linoleic acid were main components, respectively. Stepwise regression analysis revealed that shoot dry mass, days to ripening and seed length were the most important traits associated with seed yield, fatty oil yield and essential oil yield. Hence, these traits can be considered as important indicators for early selection for seed yield and quality in black cumin breeding programs.     

微量元素叶面喷施对水稻(Oryza sativa L.)产量及其构成因素的影响

[目的]基于微量元素在水稻营养和代谢中的重要作用,研究叶面喷施(Fe EDTA 0.1％,Zn EDTA 0.05％,B 0.02％,Cu EDTA 0.05％,and Mn EDTA 0.05％)对水稻品种Shiroodi产量的影响,明确叶面喷施微量元素的最佳次数和时期.[方法]为了准确评估液体肥料(Fe-EDTA ...     

Allelopathic effects of <Emphasis Type="Italic">Thymus kotschyanus</Emphasis> on seed germination and initial growth of <Emphasis Type="Italic">Bromus tomentellus</Emphasis> and <Emphasis Type="Italic">Trifolium repens</Emphasis>

The allelopathic influence of aqueous extracts of Thymus kotschyanus on Bromus tomentellus and Trifolium repens germination (%), germination speed, and seedling growth (length, fresh and dry weight) was examined. It was noted that aqueous extracts had a considerable inhibitory effect on target plant germination, and the effect at 50%, 75%, and 100% concentration was found to be significantly higher than that at lower concentrations (5% and 25%) and control treatment (distilled water). Seedling length in addition to fresh and dry weights was also reduced significantly over control. The inhibitory effect was increased as the extract concentration was increased. B. tomentellus showed a higher sensitivity against T. kotschyanus in allelopathic effects compared to T. repens, which indicates that B. tomentellus planted in rangelands with leaf litter of T. kotschyanus will be adversely affected in terms of its germination, growth, and ultimately low forage production.     

Effect of calcium carbonate nanoparticles on barrier properties and biodegradability of polylactic acid

In this study, the effect of calcium carbonate (CaCO₃) nanoparticles on the barrier properties and biodegradability of polylactic acid (PLA) was investigated. For this purpose, nanocomposite films with various CaCO₃ nanoparticle contents (0, 3, 5, 10, and 15 wt%) were prepared by solution casting method. The gas permeability of nitrogen (N₂), oxygen (O₂), and carbon dioxide (CO₂) was evaluated through a constant volume and variable pressure apparatus at different pressures and temperatures. According to results, barrier properties were improved by loading CaCO₃ nanoparticles up to 5 wt%, and the gas permeability of CO₂, O₂, and N₂ was decreased from 1.4, 0.31, and 0.07 Barrer to 0.48, 0.095, and 0.019 Barrer, respectively. In addition, it was also observed that the gas permeability of samples was decreased by increasing feeding pressure and increased by enhancing temperature. Furthermore, morphological results confirmed the formation of agglomerations and large clusters over 5 wt% CaCO₃ nanoparticles. Finally, the thermal properties and biodegradability of PLA were increased by employing CaCO₃ nanoparticles. These results suggested PLA nanocomposites as favorable candidates for food packaging applications.     

Investigation of the efficiency of direct and indirect regeneration in evening primrose (Oenothera biennis)

As a medicinal plant, the importance of evening primrose (Oenothera biennis L.) is due to its unsaturated fatty acids in the seeds and roots, and also oenotherine and comfarol in the leaves. Low germination and difficulties in seed production are the main problems encountered with growing this plant in the field. As an alternative approach, an in vitro experiment was set up for the evaluation of evening primrose production via direct and indirect regeneration of the cultivars NC-1 and VNK. For callogenesis and direct regeneration, the explants from the apical bud and petiole were cultured on MS medium supplemented with 0.25, 0.75, and 1.25 mg L^?1 of both BAP and Kinetin (KIN). Indirect regeneration was performed by placing apical buds, petioles, and leaf explants on MS medium supplemented with 0.5 and 1 mg L^?1 2,4-D and 0.5, 1, and 1.25 mg L^?1 of both BAP and KIN. The highest shoot induction from direct regeneration was obtained with apical bud explants of VNK treated with 0.75 mg L^?1 BAP. The highest callus weight (3.17 g) obtained from indirect regeneration was with petiole explants treated with 1 mg L^?1 2, 4-D and 1 mg L^?1 BAP in VNK cultivars. The highest number of torpedo embryogenic clusters (23.8) was obtained from the VNK petiole explants treated with 0.5 mg L^?1 2, 4-D and 1.25 mg L^?1 BAP. BAP had higher positive effects on in vitro production of evening primrose than KIN in both direct and indirect regeneration. In general, results indicated that VNK was more potent for regeneration than NC-1 and concentrations of 0.75 mg L^?1 BAP for direct and 0.5 mg L^?1 2, 4-D and 1.25 mg L^?1of BAP for indirect regeneration had a higher efficiency for increasing in vitro production of evening primrose.