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Showing 11 results for Bayram


Volume 13, Issue 7 (Supplementary Issue - 2011)
Abstract

Gross rainfall (GR) partitioning into throughfall (TF), stemflow (SF) and interception loss (I) was studied in a pure oriental beech (Fagus orientalis Lipsky) forest located in the central Caspian region of northern Iran. Measurements were performed on a rainfall event basis in a 5625 m2 plot of the Kheyrud Forest Research Station of Tehran University during 2008 and 2009 growing seasons. GR was measured with three rain gauges located on the ground in an open area approximately 160 m apart from the study plot. Thirty-six manual gauges were used to collect the TF and were placed randomly underneath the canopy. SF was collected with spiral type SF collection collars from six selected beech trees. Interception losses were calculated as the difference between GR and the sum of TF and SF. Over the measurement period, 53 GR events were recorded. Cumulative GR depth was 1,001.5 mm; TF amount was 728 mm; SF was 32.3 mm, and I was 241.2 mm. The average of TF/GR, SF/GR, and I/GR ratios for each rainfall events were 69.4%, 2.5% and 28.1%, respectively. TF, SF, and I were found to be closely related to GR amounts. A strong positive correlation was found between SF/GR and GR (R2= 0.9). Significant correlations were also observed between I/GR and GR (R2= 0.581) as well as between TF/GR and GR (R2= 0.414). It was observed that for small GR events a large portion of the incident GR wetted the canopy and, subsequently, contributed to the evaporation losses of the intercepted rain. Results of the study demonstrate how I represents a remarkable percentage of the incident GR and how TF and SF are both strongly affected by GR itself.

Volume 14, Issue 1 (2-2025)
Abstract


The beet armyworm, Spodoptera exigua (Hubner) (Lepidoptera: Noctuidae), poses a significant threat to beet plants, adversely affecting their yield. This study assessed the demographic parameters of this pest on seven commercial fodder beet cultivars, including “Kyros”, “1025”, “Geryty”, “Alianka”, “Laciana”, “Kara”, and “Enermax” under controlled laboratory conditions (27 ± 1 °C, 65 ± 5% RH, 16:8 h L: D). We selected 70 eggs, each less than 12 hours old, from a laboratory-reared generation and monitored their development, mortality, and oviposition daily until the death of the last individual. Data were analyzed using age-stage two-sex life table approach. The duration of the immature stages varied significantly among cultivars, with the total developmental period ranging from 23.79 days on “1025” to 33.25 days on “Laciana”. Immature survival rates also differed, with the highest survival recorded for “1025” (88.57%) and the lowest for “Kyros” (37.14%). Net reproductive rates (R0) were highest for “Alianka” (385.81 offspring) and lowest for “Laciana” (110.97 offspring). The intrinsic rate of increase (r) varied across cultivars, with values of 0.149, 0.214, 0.160, 0.180, 0.125, 0.156, and 0.193. Our findings indicate that “1025” is the most susceptible cultivar to the beet armyworm, while “Laciana” is the most resistant. These results are valuable for developing targeted beet armyworm management programs in different fodder beet cultivation regions.

 

Volume 19, Issue 1 (5-2016)
Abstract

Objective: This study aims to investigate the testes cultures of patients with previous histories of maturation arrest in spermatogenesis and find the appropriate methods to overcome this problem.
Methods: We divided spermatogonial stem cells (SSCs) isolated from testes biopsies into 3 groups: 1) culture of SSCs without feeder layer; 2) co-culture of SSCs with patient-derived Sertoli cells; and 3) co-culture of SSCs on Sertoli cell feeder layer derived from healthy donors. We calculated the numbers and diameters of stem cell-derived colonies and the percentage of cell viability in the different groups. The presence of SSCs at different culture times was determined by immunochemistry, alkaline phosphatase, and xenotransplantation of SSCs into an azoospermic mouse model.
Results: The microenvironment of the feeder layer derived from the patient’s own Sertoli cells produced numerous (36.1±4) large colonies (213.2±17 µm) after 3 weeks of culture. However, the ratio of germ cell-specific expressions of Stra8 (2.3) and Vasa (2.2) was more than the pluripotency gene, Nanog (0.45) in SSCs cultured on the Sertoli cell layer of a healthy person. After xenotransplantation of human SSCs into the testis of an azoospermic mouse model, we observed that the cells grow on basement membrane of seminiferous tubules, which confirmed their nature.
Conclusion: SSCs could be co-cultured with Sertoli cells derived from healthy donors in order to overcome the arrest of spermatogenesis observed in the co-culture of SSCs with patient-derived Sertoli cells. The results of the present study indicated that spermatogenesis could possibly be resumed in cancer patients previously treated by chemotherapy and∕or radiotherapy.

Volume 19, Issue 2 (9-2016)
Abstract

Nowadays fertility and survival of generation highly considered in societies and male infertility raised as a major attitude for community health around the world. 14% of young couples in Europe have infertility problems. In Iranian couples the rate of infertility is higher than world standards and is about 20.2%. Hormonal factors, genetics and psychological problems cause 40-50 % of infertility in men. Since cancer patients are increasing progressively in industrialized societies and anti-cancer treatments highly eliminate the germ cells, so following cancer treatment reduce male fertility. Distinguish of primordial germ cells, recognition of their migration and also understanding of effective factors in differentiation of them can extended new ways for primary studies that follow production of germ cells from other cell sources like mesenchymal stem cells (MSC). Hence finding a way to distinguish germ cells from mesenchymal stem cells, preservation and proliferation of them in culture system can provide a base for spermatogenesis in vitro culture. Isolation and differentiation of germ cells from different cell sources such as umbilical cord using morphogens (Bone morphogenesis protein and Retinoic Acid) is an efficient method for infertility research. In this study some effective factors in differentiation of umbilical cord mesenchymal stem cells to germ cells has been investigated.

Volume 20, Issue 7 (Supplementury Issue 2018)
Abstract

 We aimed to find the meteorological parameters that affect variations in Leaf Area Index (LAI) of Persian oak (Quercus brantii var. persica) trees in the Zagros region of western Iran. Canopy developmental stage for five individual trees using a fish eye camera was monitored from August 2015 to August 2016. Meteorological parameters of Temperature (T), Precipitation (P), and Wind Speed (WS) were obtained from the nearest meteorological station during 1986-2016. FAO Penman-Monteith (PM) combination equation was employed to calculate daily reference Evapotranspiration (ET0). The nonparametric Mann–Kendall (MK) test was used to detect significant changes in yearly meteorological parameters and ET0. Over the study period, LAI varied from zero during the LeafLess Period (LLP), when the Woody Area Index (WAI) was 0.88, to 1.65 in Full Leaf Period (FLP). LAI showed relatively strong and significant positive linear correlations with T (R2= 0.71), Vapor Pressure Deficit (VPD) (R2= 0.58), and ET0 (R2= 0.33), such that higher LAI values were measured in warmer and drier days with higher ET0. No statistically significant trend was detected by MK test during 1986-2016 for yearly T and VPD (MK statistic, ZMK= 0.044 for T, and ZMK= 0.207 for VPD). Significant relationship between leaf area index of oak trees and temperature in the Zagros region can partially confirm the connection between declining oak trees and rising temperature.

Volume 21, Issue 4 (7-2019)
Abstract

In this study, two essential oils including Cuminum cyminum (L.) and Lavandula angustifolia (Mill.) were nano-capsulated by solvent evaporation emulsion method and their fumigant toxicity was investigated against three important stored-products pest, Tribolium castaneum (Herbst), Sitophilus granarius (L.), and Oryzaephilus surinamensis (L.). Moreover, the sublethal concentrations of phosphine gas in combination with nano-capsules were evaluated to reduce their usage concentration. The synthetized nano-capsules were confirmed by Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR). The chemical compositions analysis of C. cyminum and L. angustifolia by GC-MS revealed that α-Pinene (44.63%) and Linalyl acetate (61.74%) were the major components of C. cyminum and L. angustifolia, respectively. The results showed that pure C. cyminum was more effective than L. angustifolia regarding the fumigant toxicity after 24 h treatment on the three mentioned stored products pests. The LC50 values of pure C. cyminum oil after 24 h treatment were obtained as 42.51 and 78.99 μL L-1 air by S. granarius and T. castaneum, respectively. However, the LC50 values of C. cyminum oil nano-capsule form were 220.34 (S. granaries) and 374.16 μL L-1 air (T. castaneum), which were determined as susceptible and resistant pests, respectively. The results indicated that the combination of nano-capsulated form of essential oil with reduced amounts of phosphine could be used as a suitable method for control of stored product pests. 

Volume 21, Issue 4 (7-2019)
Abstract

Breeding high-quality wheat cultivars is one of the main targets of breeding programs. Identification of High Molecular Weight Glutenin Subunits (HMW-GS) and Low Molecular Weight Glutenin Subunits (LMW-GS) alleles that confer high quality may be one of the easy ways to determine promising wheat lines in early generations. HMW-GS and LMW-GS alleles of 64 bread wheat (Triticum aestivum L.) genotypes from a Turkish breeding program including advanced lines and cultivars were identified using Sodium-Dodecyl-Sulfate PolyAcrylamide Gel (SDS-PAGE) electrophoresis method. In total, 26 alleles were identified including three alleles at the Glu-A1 locus, 6 alleles at the Glu-B1 locus, 2 alleles at the Glu-D locus, 6 alleles at the Glu-A3 locus, 7 at the Glu-B3 locus, and 2 alleles at the Glu-D3 locus. The most prevalent alleles among the 64 genotypes in the study were 2* (67.2%), 7+9 (42.2%), 5+10 (68.8%), A3c (28.1%), B3b (35.9%), and D3c (92.2%). The previously announced good flour quality conferring alleles 1, 17+18, 5+10 at Glu-1 loci and A3b, A3c, B3b, B3c, B3d, B3g at Glu-3 loci were also identified in the present study, indicating that these alleles can be used as markers for selection of higher-quality genotypes in wheat breeding programs. Introduction of the allele structure of the studied genotypes may enlighten the way for the wheat breeders in the crossing decisions.
 

Volume 22, Issue 1 (Winter 2018)
Abstract

Primordial germ cells (PGCs) are the specialized cells that are created from epiblast cells and after the migration differentiate into spermatogonial cells. Also, Spermatogonial cells differentiate into spermatids during the spermatogenesis process. Created disorders in each of these stages cause infertility, so the recognizing of the mechanism of these cells from the early stages of formation to the differentiation and investigating the effective factors in differentiation can be useful in the treatment of the infertile people. Today, the cultivation of spermatogonial cells and transplantation of these cells can be effective in the investigation of spermatogonial stem cell and the treatment of infertility. In this paper, the formation and migration of primordial germ cells, the spermatogenesis process and the effective factors in differentiation of spermatogonial stem cells are investigated.


Volume 22, Issue 1 (Winter 2018)
Abstract

Introduction: Due to increase of infertile couples, potential differentiation and proliferation of umbilical cord mesenchymal stem cells (MSCs) and bone marrow stem cells (BM-MSCs) was compared to find proper stem cells for differentiation into germ-like cells.
Materials & Methods: In this experimental study, isolated umbilical cord and bone marrow mesenchymal stem cells were treated by Retinoic acid (10-6M) and Sertoli cells condition medium. Viability percentage and the rate of proliferation (population doubling time) of cells was calculated in both groups. The number of colonies was evaluated in different days of culture, and finally the expression of and meiotic genes investigated by RT-PCR.
Findings: The viability percentage was higher in BM-MSCs group and the rate of proliferation of cells increased by elevating the passage number. The number of colonies in the bone marrow stem cells was significantly higher than that of the umbilical cord MSCs (p<0.05). In contrast, the expression of PLZF, OCT4 and SCP3 genes were detected in umbilical cord MSCs after 10 days of culture. However, in BM-MSC, the expression of PLZF and SCP3 genes was observed only after 15 days of culture.
Conclusion: It seems that the human umbilical MSCs higher differentiation potential for producing germ-like cells when compared to the Bone marrow stem cells. In contrast, the proliferation potential of BM-MSCs is greater than umbilical cord MSCs. This difference is probably due to secreted growth factors from these cells.


Volume 24, Issue 2 (3-2022)
Abstract

Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae) damages potato, tomato, and eggplant, and is one of the most serious agricultural pests all over the world. Due to its resistance against chemical insecticides and some biopesticides, new biocontrol agents compatible with different ecological conditions are needed urgently for the integrated pest management programs of this pest. For this purpose, we studied the insecticidal effects of thirteen indigenous microbial isolates including entomopathogenic bacteria, fungi, and nematodes from our culture collection against L. decemlineata with screening and dose-response tests under laboratory conditions. Bacillus thuringiensis strain Xd3 caused 83% and 73% mortality against larvae and adults of the pest at 109 CFU mL-1 concentration within 10 days, respectively. While fungal isolate Metarhizium anisopliae Gg-12 yielded 98% mortality with 107 conidia mL-1 concentration on larvae at 15 days, mortality provided by Gg-12 on adults reached 100% at the same concentration and period. Steinernema websteri AS1 was determined as the most effective entomopathogenic nematode with 92% mortality within seven days on larvae. Based on probit analysis, the LC50 values of B. thuringiensis Xd3 against larvae and adults were calculated as, respectively, 1.73×106 and 1.69×107 CFU mL-1, and that of M. anisopliae Gg12 were 1.18×104 and 6.2×103 conidia mL-1, and that of S. websteri AS1 was 117 IJs mL-1. Considering these results, the biopesticides developed from these isolates can be used safely and successfully in the pest management control programs of Colorado potato beetle.

Volume 24, Issue 6 (11-2022)
Abstract

Potato Tuber Moth (PTM), Phthorimaea operculella (Zeller), is one of the most destructive pests of potatoes under field and storage conditions. Exploiting plant resistance may help control the pest in an eco-friendly manner. Therefore, the present study aimed to assess the resistance status of six common potato cultivars (Banba, Bellini, Draga, Marfona, Jelly, and Milva) under laboratory conditions (25±1°C, 65±5% RH and 14:10 (L: D) hours photoperiod). Life history and demographic parameters of P. operculella under laboratory conditions were analyzed based on the age-stage, two-sex life table theory, which could be appropriate indices in resistance and susceptibility evaluation of potato cultivars. Pre-adult development was slower on Marfona and faster on Banba (19.91 and 21.93 days, respectively) compared to the other cultivars. The longest oviposition days was found on Jelly (8.20 days), while the shortest (5.43 days) was on Bellini. The maximum values of r and λ were found on Marfona (r= 0.160 d-1, λ= 1.173 d-1), whereas the minimum values were recorded on Draga (r= 0.092 d-1, λ= 1.096 d-1). According to the findings of the present study, Draga was considered resistant and a less favorable host plant for the development and reproduction of PTM. These demographic data may be used to better understand the population dynamics of the pest on the six potato cultivars tested, thereby inevitably improve efficient pest management approaches for PTM in both organic and conventional production systems.
 

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