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11.
Aquaculture International - The world population continues to increase day by day. Therefore, aquaculture needs to grow in order to response the need for protein foods and to cope with the problem...  相似文献   
12.
In previous studies, combined inclusion of Zn, Mn and Se in early weaning diets improved larval growth, but suggested a potential toxicity by one of these elements. The present study aimed to determine the effect of the single inclusion of Zn, Mn, Se or Cu, their combination (Control+) or their absence (Control?) on larval diets. At the end of the trial, survival was significantly (p < .05) lowest in fish fed C+ diet (17.16 ± 7% mean ± SD), followed by that of larvae fed Mn diet (21.91 ± 7%). The highest survival was obtained by Cu diet (35.27 ± 15%), followed by C? diet (34.58 ± 9%). Cu and Se supplementation significantly improved total length and body weight, in comparison with the C? fish. On the contrary, fish fed Mn and C+ showed the lowest growth. Supplementation with Zn or Cu significantly increased CuZnsod, whereas gpx was significantly upregulated in fish fed Se and C+ diets. ARA/EPA level was significantly highest and DHA/EPA lowest in larvae fed the Cu diet in fish fed C+ diet. The results pointed out the importance of supplementation with Cu, as well as Se and Zn, on early weaning diets for gilthead sea bream, and the potential toxic effect of Mn.  相似文献   
13.
M. Mert    S. Kurt    O. Gencer    Y. Akiscan    K. Boyaci  F. M. Tok 《Plant Breeding》2005,124(1):102-104
Verticillium wilt, caused by Verticillium dahliae Kleb., is a major constraint to cotton production in almost all countries where cotton is cultivated. Developing new cotton cultivars resistant to Verticillium wilt is the most effective and feasible way to combat the problem. Little is known about the inheritance of resistance to Verticillium wilt of cotton, especially that caused by the defoliating (D) and nondefoliating (ND) pathotypes of the soil‐borne fungus V. dahliae. The objective of this study was to determine the inheritance of resistance in cotton against both pathotypes of V. dahliae. Crosses were made between the susceptible parent ‘Cukurova 1518’ and each of four resistant parents PAUM 401, PAUM 403, PAUM 405 and PAUM 406 to produce F2 generations in 2002 and F2:3 families in 2003. Disease responses of parent and progeny populations to the D and ND pathotypes were scored based on a scale of 0‐4 (0, resistant; 4, susceptible). F2 populations inoculated with the D pathotype showed a 3 : 1 (resistant : susceptible) plant segregation ratio. Tests of F2:3 families confirmed that resistance was controlled by a single dominant gene. In contrast, analysis of data from F2‐ and F2‐derived F3 families suggested that resistance to the ND pathotype is controlled by dominant alleles at two loci.  相似文献   
14.
Summary

Pollen morphology and ultrastructure are described for four male-fertile cultivars (‘Firdola’, ‘Karamehmet’, ‘Sar?a?lama’, and ‘Hac?ömer’) and two male-sterile cultivars (‘Osmanog?lu’ and ‘Vakit Kestanesi’) of chestnut (Castanea sativa Mill.) using light microscopy and both scanning and transmission electron microscopy. Pollen grains of both male-fertile and male-sterile chestnut cultivars are tricolporate, the germinal furrow extending almost the full length of the grain axis. Pollen grains have a slightly reticulate exine. Pollen grain length varied from 13.33 – 21.30 µm, and decreased significantly in the male-sterile cultivars. Three different pollen shapes were observed among the cultivars: prolate, perprolate, and sub-prolate. The ultrastructure of the pollen grains did not differ between male-fertile and male-sterile cultivars. Intine, exine and total wall thickness (exine + intine) of pollen grains were determined as: 83.2 – 153.1 nm, 432.8 – 520.0 nm, and 516.0 – 651.6 nm, respectively; and variations were significant (P ≤ 0.05) among cultivars. The percentages of in vitro germination of pollen grains of male-fertile cultivars were between 11 – 78%, and the variations among cultivars were significant (P ≤ 0.05). The percentages of empty pollen grains observed among cultivars ranged from 3 – 32%. The correlation coefficient between the percentage of normal pollen and the germination rate was r = 0.898 (P ≤ 0.01).  相似文献   
15.
Kivçak B  Mert T 《Fitoterapia》2002,73(3):242-243
n-Hexane, ethanol and water extracts of Laurus nobilis L. leaves were evaluated for cytotoxic properties using the Brine shrimp bioassay. Only the n-hexane extract exhibited cytotoxic activity.  相似文献   
16.
Fires have a noteworthy role to play with regards to ecological and environmental losses in Mediterranean forests. In addition to ecological impacts, fire may create economic, social as well as cultural changes. The detection of fire-scars has critical importance to help decrease losses. In the present study, forest fires recorded in Antalya, one of the most important ecological and tourist regions within the Western Mediterranean, were clustered and mapped. Since the dominant factors and devastation records derived from the cases had nominal-scaled properties, a categorical data-based nonparametric clustering algorithm was performed in this evaluation. The proposed tool, k-modes algorithm, uses modes instead of means for clustering. The algorithm may be implemented quickly and does not make distributional assumptions concerning the available data. It uses a frequency-based method to update the modes of the fires. The derived modes from the maps may be useful information for local authorities to manage. In conclusion, the proposed nonparametric clustering procedure may be employed to build a decision-support system to monitor and identify fire activities and to enhance fire management efficiency.  相似文献   
17.
Plant growth promoting effects of Bacillus subtilis EY2, Bacillus atrophaeus EY6, Bacillus spharicus GC subgroup B EY30, Staphylococcus kloosii EY37 and Kocuria erythromyxa EY43 were tested on strawberry cv. ‘Fern’ in terms of fruit yield, growth, chlorophyll reading value, leaf relative water content (LRWC), membrane permeability and ionic composition of leaves and roots under saline conditions. Compared with 0 mM sodium chloride (NaCl) treatment, the average decrease of yield and LRWC were 51.6% and 21.0%, respectively, when 35 mM NaCl was applied. However, EY30, EY37, and EY43 treatments under saline condition (35 mM NaCl) significantly increased fruit yield (54.4%, 51.7% and 94.9%) compared with 35 mM NaCl treatment without plant growth promoting bacteria (PGPB). The LRWC increased from 72.0% in 35 mM NaCl treatment to 88.4%, 86.6%, 84.2%, 83.5%, and 86.2% by EY2, EY6, EY30, EY37, and EY43 applications, respectively. The lowest membrane permeability among the bacterial strains was obtained from EY37 treatment (37) while it was 33 and 58 in 0 mM NaCl and 35 mM NaCl treatments, respectively. The concentration of all plant tissue nutrients investigated [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)] with the exception of root phosphorus (P) and Mg concentration significantly decreased with 35 mM salt treatment. Nitrogen content of leaves varied between 3.04 and 3.14% in bacterial treatments under saline conditions while it was 2.71% in 35 mM NaCl treatment. In contrast sodium (Na) and chloride (Cl) of leaves and Cl content of roots were significantly decreased by root inoculation with all bacterial treatments in comparison to 35 mM NaCl treatment with no inoculation. Treatment with Bacillus EY30, Staphylococcus EY37 and Kocuria EY43 to strawberry plants can ameliorative the deleterious effect of salt stress on fruit yield, growth and nutrition. These results demonstrate that PGPB treatment could be offer an economic and simple means to increased plant resistance for salinity stress.  相似文献   
18.
Foot-and-mouth disease (FMD) is one of the most devastating animal diseases, affecting all cloven-hoofed domestic and wild animal species. Previous studies from our group using DNA vaccines encoding FMD virus (FMDV) B and T cell epitopes targeted to antigen presenting cells, allowed demonstrating total protection from FMDV homologous challenge in those animals efficiently primed for both humoral and cellular specific responses (Borrego et al. Antivir Res 92:359-363, 2011). In this study, a new DNA vaccine prototype expected to induce stronger and cross-reactive immune responses against FMDV which was designed by making two main modifications: i) adding a new B-cell epitope from the O-serotype to the B and T-cell epitopes from the C-serotype and ii) using a dual promoter plasmid that allowed inserting a new cistron encoding the anti-apoptotic Bcl-xL gene under the control of the internal ribosomal entry site (IRES) of encephalomyocarditis virus aiming to increase and optimize the antigen presentation of the encoded FMDV epitopes after in vivo immunization. In vitro studies showed that Bcl-xL significantly prolonged the survival of DNA transfected cells (p?<?0.001). Accordingly, vaccination of Swiss out-bred mice with the dual promoter plasmid increased the total IgG responses induced against each of the FMDV epitopes however no significant differences observed between groups. The humoral immune response was polarized through IgG2a in all vaccination groups (p?<?0.05); except peptide T3A; in correspondence with the Th1-like response observed, a clear bias towards the induction of specific IFN-γ secreting CD4+ and CD8+ T cell responses was also observed, being significantly higher (p?<?0.05) in the group of mice immunized with the plasmid co-expressing Bcl-xL and the FMDV B and T cell epitopes.  相似文献   
19.
Superhydrophobic surfaces are generally made by controlling the surface chemistry and surface roughness of various expensive materials, which are then applied by means of complex time-consuming processes. We describe a simple and inexpensive method for forming a superhydrophobic coating using polypropylene (a simple polymer) and a suitable selection of solvents and temperature to control the surface roughness. The resulting gel-like porous coating has a water contact angle of 160 degrees. The method can be applied to a variety of surfaces as long as the solvent mixture does not dissolve the underlying material.  相似文献   
20.
This study was conducted in order to investigate the effects of single, dual, and triple inoculations with Rhizobium, N2-fixing Bacillus subtilis (OSU-142), and P-solubilizing Bacillus megaterium (M-3) on nodulation, plant growth, nutrient uptake and seed yield of common bean (Phaseolus vulgaris L. cv. ‘Elkoca-05’) in comparison to control and mineral fertilizer application under field conditions in 2006 and 2007 in the cold highland in Erzurum plateau (29° 55′ N and 41° 16′ E with an altitude of 1850 m), Turkey. Bacterial inoculations significantly increased all the parameters investigated compared with the control treatment, equal to or higher than nitrogen (N), phosphorus (P), and NP treatments. The lowest shoot dry weight and chlorophyll content values were recorded in the control treatment and the bacterial inoculations increased shoot dry weight by 19.7–54.3% and chlorophyll content by 34.1–59.3% over control. Nodule dry weight significantly increased in Rhizobium alone treatment. Additionally, nodulation by native soil Rhizobium population was increased in single inoculations of OSU-142 and M-3. Significant increases of the seed yield under different inoculation treatments ranged between by 6.6% (Rhizobium + OSU-142 + M-3) and 12.2% (OSU-142 alone) over the control whereas N, P and NP applications corresponded to increases of 5.6%, 4.0% and 7.4%, respectively. All bacterial inoculations, especially triple inoculation, significantly increased uptake of macronutrients and micronutrients by common bean. In conclusion, seed inoculation with Rhizobium, OSU-142 and M-3, especially OSU-142 alone, may substitute partially costly NP fertilizers in common bean production even in cold highland areas such as in Erzurum.  相似文献   
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