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81.
AbstractThis study was aimed to determine biochemical traits related to higher phytomass production in sorghum genotypes irrigated with saline water. It was also attempted to consider whether or not forage yield production under non-saline conditions could be used as an index for for the selection of high yielding genotypes of sorghum under saline conditions. Forty-five sorghum genotypes were grown under field conditions using saline water or normal irrigation water in two growing seasons in Yazd, Iran. It appeared that salinity tolerance in sorghum genotypes, in addition to local adaption, was highly related to forage yield as well as some biochemical traits as carotenoid concentration, catalase activity, and K+/Na+ ratio. The screening method based on biochemical traits appeared to be applicable for identification of the salt-tolerant genotypes. 相似文献
82.
Complementary conservation strategies for the genus Coffea: A case study of Mascarene Coffea species
Mohammad Ehsan Dulloo Luigi Guarino Florent Engelmann Nigel Maxted John H. Newbury Frank Attere Brian V. Ford-Lloyd 《Genetic Resources and Crop Evolution》1998,45(6):565-579
No single conservation technique can adequately conserve the full range of genetic diversity of a target species or genepool. To optimize the efficiency of germplasm conservation, a range of conservation techniques needs to be applied simultaneously. In this paper we review the progress made in the application of both in situ and ex situ complementary conservation strategies and techniques to the conservation of the genus Coffea and identify areas where more research work is required. Traditionally, Coffea species have been conserved ex situ as living plants in field genebanks due to their intermediate seed storage behaviour. However, progress made in the field of biotechnology in recent years have made it possible to envisage the use of in vitro, slow growth and cryopreservation for medium- and long-term conservation of Coffea germplasm, respectively. In situ conservation is also an important option for long-term conservation, but there are no genetic reserves specifically set up for conserving Coffea. Protected areas and managed reserves offer the best opportunities for conserving Coffea. A case study for Mascarene Coffea in Mauritius is presented and a strategy for their conservation is discussed. 相似文献
83.
Ehsan Zamani Hanieh Shaki Mehdi Rafizadeh Alireza Khosravi Milad Pilehkouhi 《Fibers and Polymers》2017,18(8):1431-1437
A novel self-colored polyethylene terephthalate (PET) was synthesized using a synthesized dye, 4-amino-N-propanoic acid-1,8-naphthalimide. For this purpose, the prepared naphthalimide dye was added upon the polycondensation step and then a self-colored PET was prepared by step-growth polymerization. The characterization of synthesized self-colored PET and naphthalimide dye were carried out using TLC, FTIR, 1HNMR, DSC, UV-visible and Fluorometery. Results indicated that, the novel fluorescent yellow-green PET with appropriate properties was obtained. The glass transition temperature of self-colored PET was 70 °C and it was measured by differential scanning calorimeter, which revealed that addition of dye to the chains of polymer did not affect the context of glass transition of polymer. UV-visible spectrum indicated that, 99 percent of dye was incorporated in polymer chains chemically. Furthermore, the intrinsic viscosity of self-colored PET was 0.556 dl/g and molecular weight of polymer was around 35000 (g/mol) and measured using the viscometer technique. 相似文献
84.
Dr. Abolghasem Bahrami was among the generation of Iranian scientists in the early twentieth century who gained most of their knowledge through resources available inside the country. Educated at Dar-ul-Funun Medical School, he was a physician with a great talent in learning, especially self-teaching natural sciences and European languages. He joined the Pasteur Institute of Iran (IPI) at the early days of its foundation and became an integral contributor to this institution during the first twenty-five years of its mission. One of his first assignments at IPI was to help initiating an anti-rabies department by bringing back the rabies vaccine and its manufacturing equipment from Institut Pasteur of Paris. During his IPI years, aside from managerial tasks, he actively participated in upgrading the medical treatments and protocols used for controlling many infectious diseases. He functioned twice as the provisional director of IPI (1925-1926 and 1937-1946) and is considered as the first Iranian director of the Institute. Meanwhile, Dr. Bahrami was a significant contributor to the public health system and assumed several responsibilities such as Chief Quarantine Medical Officer, Chief of Public Health, and the Head of Public Health Administration, in order to improve public health planning throughout the country.Key Words: History of medicine, Iran, Microbiology, Pasteur Institute of Iran, Public health 相似文献
85.
Ehsan Ullah Khan Xing-Zheng Fu Jing Wang Qi-Jun FanXiao-San Huang Ge-Ning ZhangJie Shi Ji-Hong Liu 《Scientia Horticulturae》2009
In the current work attempts were made to investigate culture of leaf explants derived from in vitro seedlings of two sweet orange (Citrus sinensis (L.) Osbeck) cultivars, Bingtangcheng and Valencia. Effects of several factors, including culture medium, lighting condition, explant age and genotype on regeneration response were examined based on three parameters, percentage of explants producing shoots, mean number of shoots per explant and shoot forming capacity. Culture of the explants on shoot-inducing media (SIM) composed of MT salts supplemented with different growth regulators gave rise to disparate shoot regeneration, in which SIM1 (MT + 0.5 mg L−1 BA + 0.5 mg L−1 Kinetin + 0.1 mg L−1 NAA + 3% sucrose + 0.8% agar, pH 5.8) was shown to be the most effective medium for direct induction of shoots from leaf explants. Highly significant difference in the response of shoot bud regeneration was noted between the two cultivars, with Bingtangcheng being more responsive than Valencia. Culture of explants from fully developed leaves led to better shoot regeneration capacity in comparison to undeveloped ones. However, the two lighting conditions used herein did not cause significant difference in shoot regeneration. Phenotypic observation and randomly amplified polymorphic DNA (RAPD) analysis confirmed that all the regenerated plants from both genotypes were genetically identical to their donor plants, suggesting absence of detectable genetic variation in the regenerated plants. The data presented here demonstrated that direct initiation of plants from leaf explants has been successfully accomplished. To our knowledge, this is the first report on direct regeneration of shoots from leaf explants in Citrus, which will provide an alternative source for citrus genetic manipulation in the future. 相似文献
86.
Ehsan Karimi Hamid Reza Sadeghipour Arash Aminei 《Archives of Agronomy and Soil Science》2013,59(9):983-993
This study evaluated the potential of glauconitic sandstone as a fertilizer for supplying potassium to plants. The glauconite sandstone (Maraveh, Iran), as analyzed by X-ray fluorescence, was composed of 2.24% potassium oxide plus high contents of silicon, aluminum and ferric oxide. One-year old olive trees, Olea europaea L., were grown in sand or hydroponic culture in a greenhouse under three potassium treatments. Modified Hoagland nutrient solutions based on potassium treatments including 0.5 mM K+, 5 mM K+ and 400 g glauconitic sandstone powders (per 10 L in hydroponics and per 2.5 L in sand instead of K+ supply) were used in both cultures. Plants grown under the three different potassium treatments did not show any potassium deficiency symptoms. In the sand culture, growth and potassium content were higher in plants fed with 5 mM potassium than with the other two potassium treatments. Growth retardation and decreased potassium content in plants fed with 0.5 mM potassium were more severe in the hydroponic culture than in the sand culture. However, plants fed with 400 g glauconitic sandstone showed higher growth in the hydroponic culture than the sand culture. Thus, glauconitic sandstone has the ability to release potassium and can be utilized in combination with other potassium fertilizers. 相似文献
87.
Silicon nutrition of rice is affected by soil pH,weathering and silicon fertilisation 总被引:1,自引:0,他引:1
Silicon (Si) is a beneficial element for tropical grasses such as rice (Oryza sativa) and responses to applications of Si are common on highly weathered soils. However, the importance of pH (and hence Si speciation), weathering and fertilisation on Si uptake is still poorly understood. The responses of rice to Si fertilisation were studied in two variably weathered basalt soils (Red Ferrosol, Grey Vertosol) adjusted at different pH values (5.5–9.5) with three levels of acidulated wollastonite. Soil Si was extracted using deionised water (H2O), 0.01 M CaCl2, or 0.5 M NH4OAc. Significant increases in Si uptake and rice biomass were observed in the Red Ferrosol following fertilisation (p < 0.01). Greater biomass production was observed at lower pH, due to decreased Si sorption and higher solution Si concentrations. Silicon uptake by rice was greater at low pH, despite similar extractable Si concentrations; suggesting a relationship between Si speciation and uptake. In contrast, Si uptake and rice shoot dry matter in the less weathered Grey Vertosol were unaffected by Si fertilisation (p > 0.05) except at the highest rate and lowest pH (5.5). Solution Si concentrations were controlled by precipitation/polymerisation reactions in equilibrium with specific soil pH values rather than adsorption processes. Silicon speciation effects (monosilicic acid vs. silicate ions) were unable to be measured due to an induced phosphorus deficiency in both soils at pH values > 8.5. In conclusion, weathered soils are more responsive to Si fertilisation and Si uptake is increased at low pH. 相似文献
88.
Ehsan Bijanzadeh 《Journal of plant nutrition》2013,36(20):2560-2571
AbstractEffects of silicon (Si) priming at 0, 0.5, 1.0, and 1.5?mM on germination, ion balance, and root structure of two durum wheat cultivars at 0, 100, and 200?mM sodium chloride (NaCl) was conducted in a laboratory. An aliquot of 200?mM NaCl with 1.5?mM Si improved Behrang cultivar germination from 54 to 88%, but in Yavaros only from 49 to 85%. In Behrang, the control root length at 200?mM NaCl increased from 5.07 to 7.11?mm when treated with 1.5?mM Si, but Yavaros only increased from 3.18 to 4.09?mm. Behrang accumulated less sodium (Na+) and more potassium (K+). For mean diameter of central and peripheral metaxylem cells, Behrang benefitted more from Si amelioration than Yavaros. Salinity affected the diameter of central and peripheral metaxylem cells to a greater degree compared to vessel number. Si soil application (1.0 and 1.5?mM Si) may help to establish durum wheat seeds grown under saline conditions. 相似文献
89.
Hamid Yaghini Maryam Shirani Azin Archangi Karim Sorkheh Sajad Badfar Chaleshtori Seyed Ehsan Sangi Mahmood Khodambashi Farahnaz Tavakoli 《Euphytica》2013,194(3):305-324
Nineteen agrochemical traits of 20 almond inter-specific backcrosses progenies were evaluated and compared for three consequence years to find out their phenotypic diversity and determine the relationships of fruit quality traits in almond × peach backcrosses breeding progenies. The variation was observed for traits of phenology parameters (blooming time, ripening time), Physical parameters (fruit weight, width, height, shape, thickness, skin pubescences, colour and flower type), chemical parameters (total sugar content, soluble solids content and acidity) and sensory parameters (attractiveness, taste, and flavor) and yield. Many fruit characteristics that are important to breeders are present in this collection. A high variability was found in the evaluated almond progenies and significant differences were found among them in all studied quality attributes. Year-by-year variations were observed for majority of traits. A significant correlation was found among the fruit height, fruit width, skin pubescences and yield. Fruit height showed a significant positive correlation with fruit weight and fruit thickness and some other traits and a negative correlation with the titratable acidity, skin pubescences and fruit flavour. A high negative correlation was found between the fruit weight and titratable acidity (?0.8). Low coefficients were got between the flower colour and skin pubescences. In addition, principal component analysis it possible to established similar groups of genotypes depending on their quality characteristics and to study relationships among pomological traits in almond progenies evaluated. 相似文献
90.
Ehsan Bari Hamed Aghajani Katie M. Ohno Roya Shahi Mike D. C. Hale Mohsen Bahmani 《Forest Pathology》2019,49(2)
Wood‐decay fungi are important in forest ecosystems and play an important role in nutrient and carbon recycling. The scope of this research was to identify wood‐inhabiting and wood‐decay macrofungi and determine their ecology. We sampled standing trees and dead wood of oak and hornbeam in the northern forests of Iran, specifically in Mazandaran and Golestan provinces. We assessed the influence of field slope, elevation, site direction and the height of fungal sporocarp position on the tree. The species of wood‐inhabiting and wood‐decay fungi belonged to 11 families: Polyporaceae; Stereaceae; Ganodermataceae; Physalacriaceae; Agaricaceae; Xylariaceae; Pluteaceae; Coprinaceae; Strophariaceae; Pleurotaceae; and Hydnaceae. The most common fungal species identified belonged to the Polyporaceae and Ganodermataceae and predominantly grew on trees growing on a slope of 20%, at an altitude of 700–900 m, 0–3 m from the ground a southwesterly site direction and the northern sides of both tree species. These results indicated that field slope was the most important factor in determining fungal sporocarp abundance. 相似文献