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101.
102.
Hüseyi̇n Sevgi̇li̇ Adem Kurtoğlu Masahiko Oikawa Ahmet Mefut Rizvan Süyek 《Journal of the World Aquaculture Society》2012,43(4):560-570
This study was conducted to determine the effects of the use of farmed salmon oil (FSO) as a substitute for anchovy oil (AO) on growth and nutrient utilization performance, and proximate and fatty acid compositions of turbot, Psetta maxima. Two fish oil sources, AO and FSO, were incorporated into the diet at a level of 6.77% and fed to turbot with an initial average weight of 266.25 ± 0.53 g in brackish water for 9 wks. Each diet was tested in four replicates and fed to apparent satiation twice a day. At the end of the experiment, data of growth and nutrient utilization performances (feed conversion ratio, nitrogen, lipid and energy intakes, gains, and retentions), and organo‐somatic indices were similar between the dietary oil sources. Likewise, there were no significant differences in final whole body proximate compositions between two treatments. However, AO and FSO diets significantly affected whole body fatty acids and fatty acids classes. Briefly, FSO fish was characterized with higher n‐6 poly unsaturated fatty acids (PUFA) mainly 18:2n‐6 whereas AO fish with higher n‐3 PUFA and highly unsaturated fatty acids mainly 22:6n‐3. The whole body fatty acid profile reflected that of the diets. It is concluded that incorporation of FSO instead of AO in turbot diets supports similar growth and nutrient utilization performances but change whole body fatty acid profile. 相似文献
103.
Yildiz A 《Science (New York, N.Y.)》2006,311(5762):792-793
104.
Sezai Ercisli Emine Orhan Ahmet Esitken Nalan Yildirim Guleray Agar 《Genetic Resources and Crop Evolution》2008,55(4):613-618
Turkey is an important producer of cornelian cherries (Cornus mas L.), especially in northern Anatolia. Seed propagation and long-term human selection has given rise to a great diversity
of trees. Twenty-six cornelian cherry genotypes (CC1–CC26) from the Coruh Valley in northern Anatolia were evaluated for genetic
relationships by using Randomly Amplified Polymorphic DNA (RAPD) markers, based on 56 decamer random primers, seven of which
showed reliable polymorphisms. These seven primers generated 80 markers, with 77 (96.25%) displaying polymorphisms. Cluster
analysis of the cornelian cherry genotypes was performed based on data from polymorphic RAPD bands, by using Jaccard’s similarity
coefficient and the Unweighted pair-group method with arithmetic average (UPGMA) clustering method. A similarity matrix showed
that the highest genetic similarity (0.913) was between CC15 and CC16 and the least (0.129) was between CC4 and CC16. The
cophenetic correlation coefficient between the similarity matrix and the cophenetic matrix of the dendrogram was relatively
high (r = 0.87), supporting the validity of the dendrogram. Based on these results, RAPD analysis can be used for the characterization
and grouping of cornelian cherry genotypes. Genetically divergent genotypes identified in this study may be useful for future
breeding programs. This is the first study demonstrating that RAPD analyses can be used to differentiate and classify cornelian
cherry genotypes. 相似文献
105.
106.
The effects of silicon on nutrient levels and yields of tomatoes under saline stress in artificial medium culture 总被引:1,自引:0,他引:1
The purpose of this study was to determine the effects of silicon on the stem + leaf dry weight, fruit yield, quality and nutrient levels of tomatoes, cultured under saline stress on an artificial medium. Silicon doses (0, 0.5, 1.0, 2.0 mM) were combined in nutrient solution with 0, 44.4 and 70.4 mM NaCl in a factorial experiment with three replications. All silicon concentrations without NaCl increased stem + leaf dry weight and 1.0 mM Si increased fruit yield. Silicon increased fruit yield at 44.4 mM NaCl and steam + leaf dry weight at high NaCl concentrations. NaCl significantly increased the level of soluble solids in fruit and decreased the pH of fruit juice. Silicon significantly increased the pH of the tomato juice and decreased the number of fruits at high concentrations of NaCl. The effects of NaCl, Si and their interaction on nutrient contents and Si levels in leaves were statistically significant at different concentrations. 相似文献
107.
The structural diversity in urban forests is highly important to protect biodiversity. In particular, fruit trees and bush species, cavity-bearing trees and coarse, woody debris provide habitats for animals to feed, nest and hide.Improper silvicultural practices, intensive recreational use and illegal harvesting lead to a decline in the structural diversity in forests within larger metropolitan cities. It is important to monitor the structural diversity at definite time intervals using effective technologies with a view to instituting the necessary conservation measures. The use of satellite images seems to be appropriate to this end. Here we aimed to identify the associations between the textural features derived from the satellite images with different spatial resolutions and the structural diversity indices in urban forest stands(Shannon–Wiener index, complexity index, dominance index and density of wildlife trees).Rapid Eye images with a spatial resolution of 5 m 9 5 m,ASTER images with a spatial resolution of 15 m 9 15 m and Landsat-8 ETM satellite images with a spatial resolution of 30 m 9 30 m were used in this study. The firstorder(standard deviation of gray levels) and second order(GLCM entropy, GLCM contrast and GLCM correlation)textural features were calculated from the satellite images.When associations between textural features in the images and the structural diversity indices were assessed using the Pearson correlation coefficient, very high associations were found between the image textural features and the diversity indices. The highest association was found between the standard deviation of gray levels(SDGLRAP) derived from RVIRAPof Rapid Eye image and the Shannon–Wiener index(Hh) calculated on the basis of tree height(R2= 0.64). The findings revealed that Rapid Eye satellite images with a spatial resolution of 5 m 9 5 m are most suitable for estimating the structural diversity in urban forests. 相似文献
108.
Evren Yildiztugay Ceyda Ozfidan-Konakci Mustafa Kucukoduk Seyit Ahmet Tekis 《Archives of Agronomy and Soil Science》2017,63(2):261-275
Selenium (Se), regarded as an antioxidant, has been found beneficial for plants growing under stressed conditions. To investigate whether the Se application helps to improve stress tolerance, sodium selenite (Na2SeO3 · 5H2O, 5–15 μM) was hydroponically applied to Zea mays variety OSSK-713-roots under heat and/or PEG-induced osmotic stress (25% PEG-6000) for 8 h. The individual/combined stress caused accumulation of reactive oxygen species (ROS). While only superoxide dismutase (SOD) increased with heat stress alone, the activities of SOD, catalase (CAT) and ascorbate peroxidase (APX) increased under PEG exposure. The combination of these stresses resulted in an induction of both SOD and CAT activities. Lipid peroxidation (TBARS) levels were also high in all the stress treatments, especially under the combination treatment. Addition of Se not only improved the activities of SOD, APX and glutathione reductase (GR) in stress-treated roots, but it also changed the activities of monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR). The findings reveal that Se has a positive effect on heat and/or osmotic stress mitigation mainly by regulating the ascorbate-glutathione cycle, especially in PEG-treated plants. Under the combined stress treatment, addition of 5 µM of exogenous Se was most effective. 相似文献
109.
Alexey Morgounov Hale Ann Tufan Ram Sharma Beyhan Akin Ahmet Bagci Hans-Joachim Braun Yuksel Kaya Mesut Keser Thomas S. Payne Kai Sonder Robert McIntosh 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(3):323-340
Disease incidence and severity was studied for winter wheat variety Bezostaya 1 and susceptible checks based on data from international nurseries from 1969 to 2010 and from 51 countries across major winter wheat production regions totalling 1,047 reports. The frequency of leaf rust and stripe rust occurrence was stable over time with marked increases in severity in 2001–2010 especially in Europe and Central and West Asia. Substantial global reductions in stem rust occurrence were recorded and attributed primarily to use of resistance genes although the recent emergence of race Ug99 makes wheat more vulnerable. The occurrence of powdery mildew remained globally stable over time. It was the most important foliar disease in Western and Southern Europe, where the frequency was very high for all time periods coupled with slight increases in severity during 2001–2010. The durable resistance of variety Bezostaya 1 to all four diseases was demonstrated in the study using comparisons of disease severities of Bezostaya 1 and the most susceptible entries. The Lr34/Yr18/Pm38 pleiotrophic set possessed by Bezostaya 1 is currently an important target for selection because it is now amenable to molecular selection. Increased use of genes like Lr34 combined with strategies to minimize cultivation of extremely susceptible varieties will contribute to long term maintenance of low and non-damaging disease levels. The durable disease resistance of Bezostaya 1, combined with its adaptability and good end-use quality, was a significant reason for its huge impact in agriculture over the last 50?years. 相似文献
110.
Cytoplasmic dynein is a homodimeric AAA+ motor that transports a multitude of cargos toward the microtubule minus end. How the two catalytic head domains interact and move relative to each other during processive movement is unclear. Here, we tracked the relative positions of both heads with nanometer precision and directly observed the heads moving independently along the microtubule. The heads remained widely separated, and their stepping behavior varied as a function of interhead separation. One active head was sufficient for processive movement, and an active head could drag an inactive partner head forward. Thus, dynein moves processively without interhead coordination, a mechanism fundamentally distinct from the hand-over-hand stepping of kinesin and myosin. 相似文献