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排序方式: 共有218条查询结果,搜索用时 328 毫秒
61.
Farhadi-Tooli Sakineh Ghanbari Alireza Kermani Maryam Jafarkhani Zeinalabedini Mehrshad Bettoni Jean Carlos Naji Amir Mohammad Kazemi Nooshin 《European journal of plant pathology / European Foundation for Plant Pathology》2022,162(1):31-43
European Journal of Plant Pathology - Viral diseases affect quince plant productivity and fruit quality. This study evaluated the effectiveness of droplet-vitrification cryotherapy and... 相似文献
62.
Afrasiabian Yasamin Noory Hamideh Mokhtari Ali Nikoo Maryam Razavi Pourshakouri Farrokh Haghighatmehr Parisa 《Precision Agriculture》2021,22(3):660-688
Precision Agriculture - Leaf area index (LAI) is a key parameter for the calculation of crop biophysical and biochemical processes. Therefore, the accurate estimates of LAI has been always of great... 相似文献
63.
Iram SHAFIQ Sajad HUSSAIN Muhammad Ali RAZA Nasir IQBAL Muhammad Ahsan ASGHAR Ali RAZA Yuan-fang FAN Maryam MUMTAZ Muhammad SHOAIB Muhammad ANSAR Abdul MANAF Wen-yu YANG Feng YANG 《农业科学学报》2021,20(1):4-23
Under natural conditions, plants constantly encounter various biotic and abiotic factors, which can potentially restrict plant growth and development and even limit crop productivity. Among various abiotic factors affecting plant photosynthesis, light serves as an important factor that drives carbon metabolism in plants and supports life on earth. The two components of light(light quality and light intensity) greatly affect plant photosynthesis and other plant's morphological, physiological and biochemical parameters. The response of plants to different spectral radiations and intensities differs in various species and also depends on growing conditions. To date, much research has been conducted regarding how different spectral radiations of varying intensity can affect plant growth and development. This review is an effort to briefly summarize the available information on the effects of light components on various plant parameters such as stem and leaf morphology and anatomy, stomatal development, photosynthetic apparatus, pigment composition, reactive oxygen species(ROS) production, antioxidants, and hormone production. 相似文献
64.
Maryam?Mohammadi Loghman?KarimiEmail author Mohammad?Mirjalili 《Fibers and Polymers》2016,17(9):1371-1377
In this study, synthesis of zinc oxide nanoparticles was carried out along with the hydrolysis of polyester fabric using sodium hydroxide to increase the surface activity and enhance the nanoparticles adsorption. The polyester fabrics were treated with zinc acetate and sodium hydroxide at different bath conditions, ultrasound and stirrer, resulting in formation of ZnO nanospheres and ZnO nanorods. The presence of zinc oxide with different shapes on the surface of the polyester fabrics was confirmed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Also, the X-ray diffraction patterns established the composition of wurtzite structure of zinc oxide. The self-cleaning property of treated polyester fabrics was evaluated through discoloring dye stain under sunlight irradiation. The antibacterial activities of the samples against two common pathogenic bacteria including Escherichia coli and Staphylococcus aureus were also assessed. The results indicated that the photocatalytic and antibacterial activities of the ultrasound treated polyester fabrics were superior compared to the stirrer treated samples. 相似文献
65.
Maryam Haghighi Mohsen Kafi Amir Khoshgoftarmanesh 《Journal of plant nutrition》2013,36(10):1521-1532
The objectives of this study were to determine the effects of nitrogen (N) forms and deficient and toxic rates of boron (B) on the growth, NO3 accumulation, membrane permeability, mineral nutrition, and nitrogen use efficiency (NUE) of bunch onion (Allium cepa L. var. Radar) plants. Therefore, 20% of NO3 in reference nutrient solution was replaced by NH4, urea, or mixed amino acids (AA). To each of these solutions 3, 30, or 300 mmol m?3 B was added. Fresh and dry weights were the same in the reference and mixed AA treatments, but NH4 and urea decreased these growth parameters as compared to the reference. Mixed AA decreased the NO3-N content while urea increased it, and NH4 treatment yielded similar NO3-N content as compared to the reference. The nitrogen content of plants was increased by NO3 replacement with either NH4 and, urea or mixed AA. At the 300 mmol m?3 B rate, B content of plants was decreased by NH4 and urea, but increased by the mixed AA treatment. Membrane permeability was increased by NH4?replacement of NO3. Nitrogen use efficiency was found the highest in the reference treatment. Nitrogen and NO3-N contents were increased by the 300 mmol m?3 B rate. Increasing B in nutrient solution increased the B contents of plants. Mixed AA treatment decreased the phosphorus (P) content of plants. Potassium (K) and chloride (Cl) contents of plants were decreased in the NH4 treatment where B was applied at the 3 mmol m?3 rate. These results suggest that bunch onion growers may reduce NO3 content in onion tops by partially replacing NO3 with amino acids without reducing yield. 相似文献
66.
Hamide Ranjbarshamsi Maryam Omidi Najafabadi S. J. F. Hosseini 《Journal Of Agricultural & Food Information》2013,14(2-3):110-119
The purpose of this study was to determine the factors influencing consumers' attitudes toward organic agricultural products. The study is correlational research. Results of regression analysis indicated that the variables of health awareness, knowledge of organic products, and consumers' motivations and age explained 32% of the changes in attitudes about organic products. The authors therefore recommend educational initiatives to increase knowledge and awareness and influence attitudes and consumption habits. 相似文献
67.
Impact of land-use management on nitrogen transformation in a mountain forest ecosystem in the north of Iran 总被引:2,自引:0,他引:2
Maryam Asadiyan Seyed Mohammad Hojjati Mohammad reza Pourmajidian Asghar fallah 《林业研究》2013,24(1):115-119
Soil inorganic N is one of the most important soil quality indexes, which may be influenced by land-use change. The historical conversion of land-use from native vegetation to agriculture resulted in sharp declines in soil N dynamics. This study was conducted to determine the soil inorganic N concentrations and net N mineralization rate in four common types of land-uses in the mountain forest area in the north of Iran, namely arable land, pine plantation, ash plantation, and beech stand. The soil samples were taken from top mineral soil layer (5cm) in each site randomly (n=6) during August- September 2010. Beech stand and ash plantation showed significantly higher total nitrogen compared with arable land and pine plantation, while extractable NH 4 + -N concentration was significantly greater in Beech stand compare to arable soils (p<0.05). No significantly difference was found in Net N mineralization, net nitrification and net ammonification rates among different land-uses. Results showed that net N mineralization and ammonification were occurred just in the soil of Ash plantation during the incubation time. Our findings suggested that conversion of Hyrcanian forests areas to pine plantation and agricultural land can disrupt soil natural activities and affect extremely soil quality. 相似文献
68.
Maryam Tabatabaei John B. Loomis Daniel W. McCollum 《Journal of Sustainable Forestry》2013,32(8):720-737
We estimated Colorado households’ nonmarket values for two forest management options for reducing intensity of future wildfires and associated nonmarket environmental effects wildfires. The first policy is the traditional harvesting of pine beetle-killed trees and burning of the slash piles of residual materials on-site. The second involves harvesting but moving the residual material off-site and converting it into biochar, thus reducing some of the risk and environmental effects associated with burning on-site. A contingent valuation method mail survey was used to evaluate these two management options. The survey achieved a 47% response rate. We used a nonparametric Turnbull estimator to calculate the willingness to pay (WTP) for burn on-site and off-site biochar conversion. The calculated WTP for burn on-site and off-site biochar conversion options (beyond the cost of the status quo level of forest treatment) is $411 and $470 per household per year, respectively. 相似文献
69.
Background – Antimicrobial peptides (AMPs) have a pivotal role in cutaneous innate immunity. They are present in the skin of many animals, including mammals, and are both constitutively present and inducible by infection and injury. Functions – Antimicrobial peptides exhibit antimicrobial activity against bacteria, viruses, fungi and parasites, with different potencies depending on their peptide structure. They also act as multifunctional effector molecules that influence diverse cellular processes, including cell migration, proliferation and differentiation, cytokine production, angiogenesis and wound healing. Suppressed AMP production has been associated with increased susceptibility to microbial insults and the pathogenesis of atopic dermatitis. This review highlights recent observations on the expression and role of AMPs, particularly the AMPs cathelicidin and β‐defensin, in healthy and diseased skin. 相似文献
70.
Background: To develop a new green approach for biosynthesis of silver nanoparticles, myconanotechnology has been represented as a novel field of study in nanotechnology. In this study, we have reported the extracellular synthesis of highly stable silver nanoparticles using three species of dermatophytes: Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum canis. Methods: Clinical strains of these species were grown in a liquid medium containing mineral salt and incubated at 25°C for 5-7 days. The cell-free filtrate of each culture was obtained and subjected to synthesize silver nanoparticles in the presence of 1 mM AgNO3. Results: The reduction of Ag+ ions in metal nanoparticles was investigated virtually by tracing the solution color which was switched into reddish-light brown after 72 h. For T. mentagrophytes, a UV-visible spectra demonstrating a strong, quite narrow peak located between 422 and 425 nm was obtained. For M. canis, a fairly wide peak centering at 441 nm and for T. rubrum, a weak spectrum to decipher were observed. According to transmission electron microscopy (TEM) results, fairly uniform, spherical, and small in size with almost less than 50 nm particles were forms in case of T.
mentagrophytes. For the other two species, TEM images showed existence of small spherical nanosilvers but not as small as nanoparticles synthesized by T. mentagrophytes. Conclusion: We observed that species belong to a single genus of the fungi have variable ability to synthesize silver nanoparticles extracellulary with different efficiency. Furthermore, the extracellular synthesis may make the process simpler and easier for following processes.Key Words: Nanoparticles, Dermatophytes, Extracellular biosynthesis 相似文献