Effects of repeated administration of hCG on follicular and luteal characteristics and serum progesterone concentrations in eCG-superovulated Sanjabi ewes

The objective of this study was to evaluate if treatment of equine chorionic gonadotrophin (eCG)-superovulated Sanjabi ewes with repeated administration of human chorionic gonadotropin (hCG) would increase the number of normal corpus luteum (CL) and serum progesterone concentrations and decrease the number of persistent follicles. The superovulated ewes were divided into four groups on day 0 (day of sponge removal); the ewes were treated by an intramuscular administration of 500?IU hCG on day 0 (Group I: n?=?10), on days 0 and 1 (Group II: n?=?10), or on days 0, 1, and 2 (Group III: n?=?10) and no treatment for control group (n?=?10). Blood samples were collected on days 0, 1, 2, 5, and 8 (day of slaughter), and serum progesterone concentrations were determined. According to progesterone concentrations, 50 (4/8) and 0?% of the ewes underwent premature luteal regression in the control group and the hCG groups, respectively. There were more CLs in Group III than in Group II and the control group. Ewes treated with hCG had a greater number of normal-looking CL. CL diameter was significantly greater in Group II and Group III than other groups. Total CL weight was significantly (P?<?0.05) higher in Group III than in Group I and the control group. Number of persistent follicle and persistent follicle diameter were lower in control group compared to the other groups. Eight days after sponge removal, serum progesterone concentration was significantly higher in Group III than in Group I and the control group. The present results indicate that repeated administration of hCG supported CL formation, increased serum progesterone concentration, and prevented premature luteal regression in eCG-superovulated Sanjabi ewes.     

Spatially distributed monthly reference evapotranspiration derived from the calibration of Thornthwaite equation: a case study, South of Iran

The Penman-Monteith equation is the most common method for estimating reference crop evapotranspiration (ET_o). Using this method reqiures many different meteorological data, yet few stations with adequate meteorological data may exist in a region. Setting up a station that records the required data for Penman-Monteith equation is expensive. Alternatively, the Thornthwaite equation is a simpler method for estimating ET_o since it is a temperature-based method. In this study, the Thornthwaite equation was spatially calibrated based on the Penman-Monteith method (as the standard and reference method to compute ET_o) for every month of the year, using the meteorologica data of seven synoptic weather stations in Fars province, and seven synoptic stations outside the Fars province. The Thornthwaite equation using effective temperature that has been introduced recently in other studies was used (Camargo et al. in Revista Brasileira de Agrometeorologica 7:251–257, 1999). For this purpose a calibration coefficient k must be determined. The results of the spatial and temporal calibration of the new approach using the Thornthwaite equation showed that for each station different k values should be used monthly. Generally, the k values fluctuated between 0.55 and 1.12, and the mean RMSE for all stations was less than 1 mm day⁻¹, which showed good and reliable agreement between the ET_o estimations obtained from the Penman-Monteith and calibrated Thornthwaite equations. Depending on the geographical location of each station, spatial distribution maps of monthly k values were created for the study area using the inverse distance weighting (IDW) interpolation method. It is therefore possible to estimate monthly ET_o using the appropriate k map and the Thornthwaite equation for different regions of study area instead of using the Penman-Monteith method. This case study showed that the same analysis might be used for the other parts of the country or any part of the world and would result in efficient scheduling of water resources for agriculture.     

Estimation of lucerne yield stability for enabling effective cultivar selection under rainfed conditions

Evaluation of crop and forage yield stability is of increasing relevance in the context of current and recent environmental changes but, in contrast to other field crops, there are no published systematic analyses among forage crops in Europe. A study of stability performance was conducted with 13 Czech cultivars of lucerne at four locations over a 2‐year period with the following aims: (a) to evaluate yield stability of varieties across different environments and (b) to calculate measurable benefits of variety selection in relation to the specific environment. The cultivar Vlasta was identified as the highest yielding cultivar (annual yield 16.0 t DM/ha), whereas the lowest yielding cv. Magda, Tereza and Oslava averaged around 14.9 t DM/ha. Effect of genotype × environment interaction (G × E) was two times higher than for genotype alone. Additive main effects and the multiplicative interaction (AMMI) model showed that the highest yielding cultivars may not be stable across environments. This study demonstrated further that significant yield improvement could be detected, even among a relatively homogenous group of domestic cultivars, and this was driven mainly by site productivity: the improvement was +10% in low‐yielding sites, compared with +3% in high‐yielding sites. Results highlight that advanced agronomy should also consider stability parameters such as AMMI stability value or superiority measures for forage crops in response to the challenges associated with climate change.     

Assessment of genetic diversity and relationships among <Emphasis Type="Italic">Triticum urartu</Emphasis> and <Emphasis Type="Italic">Triticum boeoticum</Emphasis> populations from Iran using IRAP and REMAP markers

Einkorn wheat is known as the donor of ‘A’ genome to cultivated wheat and source of many important genes. Therefore, genetic erosion in cultivated wheat provides a good reason to investigate genetic diversity in these species. In the present study, genetic diversity of 14 populations of Triticum urartu and Triticum boeoticum collected from west and north-west of Iran was examined by IRAP and REMAP markers. In total, 26 out of 36 IRAP and 41 out of 88 REMAP combinations amplified polymorphic and scorable banding patterns. IRAP and REMAP combinations produced 6.53 and 5.21 polymorphic bands per assay, respectively. Mean of polymorphism information content for IRAPs and REMAPs were 0.38 and 0.40 and marker index values for them were 2.60 and 2.09, respectively. Analysis of molecular variance based on IRAP and REMAP data revealed significant within and among population variances, although within population variance was higher than that of among population. Primer combinations based on Sukkula and Nikita retrotransposons produced the highest number of markers in the whole population. Cluster and principal coordinate analyses using REMAP data grouped the populations based on the species and geographical origin, but grouping based on IRAP could not separate the two species. However, based on both marker systems considerable diversity was observed among and within the studied populations.     

Alleviation of Salinity Stress by Vermicompost Extract: A Comparative Study on Five Fennel Landraces

In the present study, interaction between salinity (0, 40, 80, 120 mM NaCl) and vermicompost extract (VCE) on five fennel landraces (Urmia, Mashhad, Shiraz, Boushehr, Isfahan) was investigated in a factorial experiment as completely randomized design to find the best salt-tolerant landrace and potential alleviating role of VCE. Results showed that Boushehr and Isfahan were the most tolerant and sensitive landrace to salinity, respectively. Application of VCE improved germination and growth of salt-treated fennels. The amylase activity of fennels was not affected by salinity and not improved by VCE. While sodium (Na⁺) content of root and shoot of all salt-treated fennels increased, their potassium (K) content decreased. Under salinity stress, root K content of VCE-amended landraces was more than that of not amended ones. VCE also caused an increase in calcium (Ca) content of root of salt-treated Shiraz and Urmia landraces. In conclusion, VCE can alleviate adverse effects of salinity stress on fennel.     

Incorporation of Functionalized Silica Nanoparticles into Polymeric Films for Enhancement of Water Absorption and Water Vapor Transition

Water absorption and water vapor transition are significant mechanisms in many industrial processes. Nanocomposite polymers are appropriate materials for water transition process due to their specific properties. The present work was aimed to enhance the water absorption and water vapor transition by high loading incorporation of silica nanoparticles (NPs) into polyacrylonitrile (PAN) and Pebax 1657 polymers. PAN was used to prepare both the nanocomposite films (NCFs) and support layers of nanocomposite membranes (NCMs). Pebax 1657 was used to fabricate the selective layers of NCMs. Incorporation of NPs into the NCFs were carried out using ex-situ and in-situ (sol-gel) methods. NCFs were fabricated by electrospinning and casting methods. The fabricated NCFs of fibers and polymers were examined through water absorption tests. For fabrication of NCMs, the electrospinning and dip-coating methodologies and the incorporation of NPs into the selective layers by in-situ method were used. Besides, the water vapor permeation tests have been designed and constructed to examine the NCMs for dehydration of methane gas. In order to provide efficient NPs dispersion into NCFs, the surface functionalization of silica NPs with ethylene glycol (EG) was also considered. The functionalized silica NPs were used in the fabrication of NCFs and into the selective layer of NCMs. It is found that in applying the ex-situ method, there is a lot of NPs agglomeration, while the dispersion quality of NPs is higher with the sol-gel method. In addition, the dispersion is improved greatly with functionalization of silica NPs. The water uptake ratio of electrospun mats is about 400 % higher than the cast layers for the same loadings of NPs. The water uptake ratio of the polymeric layers containing EG is about 50 % higher than the samples without EG. The permeance of water vapor for the NCM (15 wt.% of SiO₂/Pebax 1657) fabricated by sol-gel method was enhanced to 54.4 % higher than the membranes without NPs. Functionalization of silica NPs also enhanced the water vapor permeation process. For instance, the water vapor of the NCM containing 30 wt.% of EG/Pebax1657 was increased by 68.7 %.     

Tree species composition,biodiversity and regeneration in response to catena shape and position in a mountain forest

We examined the variation in woody plant species composition, regeneration and biodiversity in relation to topographic heterogeneity, specifically catena shape (V and Λ) and slope position (summit, shoulder, back slope, foot slope and toe slope). All research took place at the TMU Experimental Forest Station, located in northern Iran. Two sets of replicated quadrats were established along transects that encompassed the different catena shapes and positions. We recorded the density, height, and canopy cover of all trees ≥12 cm diameter at breast height within 30 quadrats (400m²), as well as the density of all tree regenerations within 120 quadrats (4m²). In addition, three measurements of biodiversity were calculated for both mature trees and regenerations. Mature tree species composition varied greatly with catena shape and slope position, as did that of regenerating trees. Despite differences in species composition, the various measurements of biodiversity were consistent across the landscape for mature trees, whereas significant variation in evenness was detected for regenerating trees. We concluded that the broad matrix of environmental conditions occurring within this rugged mountainous area generates a variety of microhabitats, which in turn contributes to both the variation in species composition and the consistent biodiversity of these forests.     

Effect of Different Nitrogen Doses on Dry Matter Ratio,Chlorophyll and Macro/Micro Nutrient Content in Sweet Herb (Stevia rebaudiana Bertoni)

With this study, the effect of different nitrogen (N) doses applied to sweet herb (0, 50, 100, 150 and 200 N kg ha^?1) on the macro/micro nutrient element content, dry matter ratio and on the chlorophyll amount in the plant leaves is examined. The research was carried out in the research and trial field of Faculty of Agriculture Agronomy department, Akdeniz University, during the 2012–2013 growing season under field conditions for 2 years with four replications according to the randomized block trial design. Chlorophyll amounts were determined and the average was obtained with three readings from each leaf by a chlorophyll meter when the plants were in the beginning of flowering. Post-harvest macro and micro nutrient elements of the sweet herb were also investigated. According to the obtained data, while the highest chlorophyll and N amounts in the leaf for both the first and second years were determined as 46.97 SPAD (Minolta Corp, NJ, USA) and 1.34 N% 44.9 SPAD, 1.42 N%, respectively, under 200 kg ha^?1 N application, the lowest chlorophyll and N amounts were determined in the control group. In addition, N application in different doses for both years increased the phosphorus (P) and potassium (K) contents and increased the microelement contents, especially in the second year. At the same time, a correlation between the chlorophyll content in the plant leaves and the N amount was determined and a linear increase was observed in the chlorophyll amount with the increased green part.     

Accumulation and phytoremediation of Pb,Zn, and Ag by plants growing on Koshk lead–zinc mining area,Iran

Purpose

This study investigated the extent of metal accumulation by plants colonizing a mining area in Yazd Province in Central Iran. It also investigated the suitability of these plants for phytoextraction and phytostabilization as two potential phytoremediation strategies.

Materials and methods

Plants with a high bioconcentration factor (BCF) and low translocation factor (TF) have the potential for phytostabilization, whereas plants with both BCFs and TFs >1 may be appropriate for phytoextraction. In this study, both shoots and roots of 40 plant species and associated soil samples were collected and analyzed for total concentrations of trace elements (Pb, Zn, and Ag). BCFs and TFs were calculated for each element.

Results and discussion

Nonnea persica, Achillea wilhelmsii, Erodium cicutarium, and Mentha longifolia were found to be the most suitable species for phytostabilization of Pb and Zn. Colchicum schimperi, Londesia eriantha, Lallemantia royleana, Bromus tectorum, Hordeum glaucum, and Thuspeinantha persica are the most promising species for element phytoextraction in sites slightly enriched by Ag. Ferula assa-foetida is the most suitable species for phytostabilization of the three studied metals. C. schimperi, L. eriantha, L. royleana, B. tectorum, M. longifolia, and T. persica accumulated Ag, albeit at low level.

Conclusions

Our preliminary study shows that some native plant species growing on this contaminated site may have potential for phytoremediation.

     

Wicking phenomenon in polyacrylonitrile nanofiber yarn

The aim of this paper is to investigate vertical wicking in polyacrylonitrile (PAN) electrospinning nanofiber yarn using image analysis. Colored liquid rising phenomenon into the yarn and the distance of liquid rise were determined as a function of time. The kinetics of capillary rise follows the Lucas-Washburn equation. The results show that capillary rise rate coefficient is being reduced with increasing yarn twist, due to the reduction of continuity and size of capillaries. Increasing heat treatment stretch from 0 % (draw ratio=1) to 50 % (draw ratio=1.5) increases the capillary rise rate coefficient, due to the more homogeneity of capillary spaces in the yarn structure and increasing heat treatment stretch from 50 to 100 % (draw ratio=2) reduces capillary rise rate coefficient, because of the low capillary length. The present study indicates that an appropriate choice in production parameters of nanofiber yarn is all important in obtaining the desired properties of capillary rise.