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91.
Ebru Çetin Berrin Kocaoğlu Güçlü 《Journal of animal physiology and animal nutrition》2020,104(1):136-143
This study aimed to investigate the effect of l -carnitine and energy level and on oxidant/antioxidant balance in laying hens subjected to high stocking density. A total of 176, 32-week-old laying hens were assigned to eight groups with four replicates and hens in four groups were placed at the normal stocking densities of 500 cm2/hen (four hens per cage) and in the remaining four groups were placed at the high stocking densities of 287.5 cm2/hen (seven hens per cage). Hens received diets of high (2,850 kcal/kg ME) or normal (2,650 kcal/kg ME) energy which are supplemented with 0 or 200 mg/kg l -carnitine for 70 days. Results showed that exposure to high stocking density increased (p < .05) plasma malondialdehyde (MDA) and nitric oxide (NO) levels and decreased (p < .05) erythrocyte superoxide dismutase (SOD), catalase (CAT) and superoxide dismutase (GPx) activities. l -carnitine supplementation increased (p < .05) erythrocyte SOD, CAT and GPx activities, and decreased (p <.05) MDA and NO level in high stocking densities. The oxidan/antioxidan balance of birds was not influenced by increasing dietary energy level. The results of the present study indicate that the supplementation of l -carnitine to the birds subjected to high stocking density could effectively reverse the negative effects of high stocking density by improving oxidant/antioxidant balance. Therefore, l -carnitine supplementation at level of 200 mg/kg to diet may be as a favourable alternative to deal with oxidative stress caused by high stocking density in laying hens. 相似文献
92.
Mustafa Y. Canbolat Serdar Bilen Ramazan Çakmakçı Fikrettin Şahin Adil Aydın 《Biology and Fertility of Soils》2006,42(4):350-357
Inoculants are of great importance in sustainable and/or organic agriculture. In the present study, plant growth of barley
(Hordeum vulgare) has been studied in sterile soil inoculated with four plant growth-promoting bacteria and mineral fertilizers at three different
soil bulk densities and in three harvests of plants. Three bacterial species were isolated from the rhizosphere of barley
and wheat. These bacteria fixed N2, dissolved P and significantly increased growth of barley seedlings. Available phosphate in soil was significantly increased
by seed inoculation of Bacillus M-13 and Bacillus RC01. Total culturable bacteria, fungi and P-solubilizing bacteria count increased with time. Data suggest that seed inoculation
of barley with Bacillus RC01, Bacillus RC02, Bacillus RC03 and Bacillus M-13 increased root weight by 16.7, 12.5, 8.9 and 12.5% as compared to the control (without bacteria inoculation and mineral
fertilizers) and shoot weight by 34.7, 34.7, 28.6 and 32.7%, respectively. Bacterial inoculation gave increases of 20.3–25.7%
over the control as compared with 18.9 and 35.1% total biomass weight increases by P and NP application. The concentration
of N and P in soil was decreased by increasing soil compaction. In contrast to macronutrients, the concentration of Fe, Cu
and Mn was lower in plants grown in the loosest soil. Soil compaction induced a limitation in root and shoot growth that was
reflected by a decrease in the microbial population and activity. Our results show that bacterial population was stimulated
by the decrease in soil bulk density. The results suggest that the N2-fixing and P-solubilizing bacterial strains tested have a potential on plant growth activity of barley. 相似文献
93.
MATTSON MARK D. GODFREY PAUL J. WALK MARIE-FRANÇOISE KERR PETER A. ZAJICEK O. THOMAS 《Water, air, and soil pollution》1997,96(1-4):211-232
A ten year survey of water quality in 330 Massachusetts streams was conducted to examine the rate and pattern of recovery from acidification. Meta-analysis was used to combine the results of the 330 non-parametric trend tests into an overall test for trend in a variety of water quality variables including pH, acid neutralizing capacity (ANC), and major inorganic ions. Analysis of trends in the raw data indicates both pH and ANC are increasing. After detrending for variations in stream runoff, we estimate the streams are recovering from acidification at a rate of +0.021 pH units/year and +2.4 μeq/L/year, for pH and ANC respectively. These trends appear to be related to declines in sulfate (–1.8 μeq/L/year), while base cation trends were mixed. Meta-analysis reveals the trends are not always homogeneous between seasons or between sites. While it is commonly assumed that the low ANC systems are most ‘sensitive’ to changes in acid or base inputs, we found the greatest rates of change in ANC were associated with the high ANC systems. The greatest increases in pH were seen in the low ANC streams as expected. The results also suggest streams respond quickly to changes in precipitation inputs and stream monitoring networks may be valuable as an early detection technique for changes in environmental quality. 相似文献
94.
Kazım HALAÇLAR Ayla SEVIM EROL Tolga KÖROĞLU Paul RUMMY Tao DENG Serdar MAYDA 《Integrative zoology》2024,19(3):548-563
The Çorakyerler fossil locality in Anatolia reveals unique faunal elements. This study introduces Hystrix kayae sp. nov., a new Late Miocene porcupine initially classified as Hystrix sp. Yavuz et al., 2018. This finding expands our knowledge of Late Miocene Anatolian porcupines, bringing the total number of known species to three. H. kayae sp. nov. is larger than Hystrix aryanensis and exhibits greater upper cheek tooth crown height. Its cheek tooth morphology differs from Hystrix depereti, and it possesses distinctive U-shaped choanae unlike Hystrix primigenia. The Çorakyerler locality may predate sites with H. aryanensis and H. primigenia but aligns temporally with Hystrix parvae localities. This study enhances our understanding of Late Miocene porcupine diversity in Anatolia, emphasizing the importance of Çorakyerler in unraveling the evolutionary history of these fascinating mammals. 相似文献
95.
Silvia Nietsche Aluízio Borém Geraldo Assis de Carvalhos Trazilbo José de Paula Júnor Cláudia Fortes Ferreira Everaldo GonÇalves de Barros Maurilio Alves Moreira 《Euphytica》2001,117(1):77-84
Due to the importance of common bean angular leaf spotin the state of Minas Gerais-Brazil and to the greatvariability of the pathogen, Phaeoisariopsisgriseola, monitoring races becomes an important toolfor breeding programs aiming at genetic resistance.The pathogenic variability of 30 isolates of the P. griseola, collected from various locations in thestate of Minas Gerais, was studied using the followingcommon bean differential series (Don Timóteo,Bolón Bayo, Montcalm, G 5686, Amendoin, G 11796,BAT 332, PAN 72, Cornell 49-242, México 54, Florde Mayo and G 2858). The first trifoliate leaf wasinoculated with a 2 × 104 conidia/mL. Plants weremaintained at 20–22 °C and 95% relativehumidity for 48 hours. Symptom evaluation wasperformed 15 days after inoculation. Thirteen raceswere identified demonstrating the wide geneticvariability of the pathogen in the state of MinasGerais. Race 63.63 was the most virulent, whereas race63.23 was the most frequent (10 of 30 isolates), beingwidely distributed among the regions studied. Thevirulence phenotype indicated that the races studiedbelonged to the Mesoamerican group, which wasconfirmed when the 30 isolates were compared to Andeanand Mesoamerican standards using RAPD markers. 相似文献
96.
97.
Kadriye Özcan Semiha Çetinel Aksoy Orçun Kalkan Ataç Uzel E. Esin Hames-Kocabas Erdal Bedir 《Journal of Soils and Sediments》2013,13(8):1493-1501
Purpose
Marine environments, especially sediments, are rich sources of actinomycetes that provide many bioactive compounds, primarily antibiotics. The goal of this study was to investigate the diversity of cultivable actinomycetes and their potential to produce antibiotics from sediments collected from the coastal zones of Turkey.Materials and methods
Thirty sediment samples were collected from nine different coastal sites in three seas surrounding the Anatolian Peninsula of Turkey. Of the samples, 6 were collected from one site in the Black Sea, 18 from seven sites in the Aegean Sea, and 6 from one site in the Mediterranean Sea. Strains of pure actinomycetes were isolated by modified actinomycetes isolation agar (MAIA), M1 agar, M6 agar, and modified R2A agar. Ethyl acetate extracts and fermentation broths were used for the evaluation of antimicrobial activity against antibiotic resistant test microorganisms. The identification of the isolates was undertaken by 16S rRNA gene sequencing.Results and discussion
A total of 261 strains of actinomycetes were isolated, of which 66 (25 %) were active against at least one antibiotic-resistant microorganism. Sixty-five of the actinomycetes isolates with antimicrobial activity were Streptomyces spp. and one was Nocardia sp., which implied that genus Streptomyces was predominant. Whereas MAIA agar was the best medium to recover actinomycetes, M6 agar was superior to others for the isolation of antibiotic-producing strains.Conclusions
Extensive screening of the extracts from the 261 isolates for antimicrobial activities revealed considerable potential to produce antibiotics. These findings imply that actinomycetes from marine sediments of the Anatolian Peninsula coasts have potential for the discovery of novel bioactive compounds. 相似文献98.
New record of invasive mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) in Turkey
This short note reports the first record of the invasive mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) in Turkey. It was found on ornamental plants in the city center of Adana (Mediterranean region), but could be a threat to cotton production in the country. 相似文献
99.
Gürcan Güleryüz Hülya Arslan Cengiz Çelik Şeref Güçer Michaela Kendall 《Water, air, and soil pollution》2008,187(1-4):275-284
The Paraíba do Sul river is located in one of the most developed part of Brazil and receives many organic and industrial effluents directly affecting the ichthyofauna. Concentration of four heavy metals (Cu, Cr, Zn and Pb) were determined in two tissues (muscle and gonads) of three abundant fish species from different trophic levels (Oligosarcus hepsetus—carnivore, Geophagus brasiliensis—omnivore and Hypostomus luetkeni—detritivore) between November 2002 and April 2003. The aim was to test the hypothesis that the trophic level and the proximity from impacted areas influence levels of contamination and to assess if these species are indicators of large-scale habitat quality. Levels of heavy metals were detected by Total Reflection X-ray Fluorescence with Synchrotron Radiation (SR-TXRF) at the Brazilian National Synchrotron Radiation Laboratory (LNLS). Generally, gonads showed higher metal concentration than muscles, except for Cr. All examined metals, but Cu, exceeded the maximum permitted concentration (mpc) by the Brazilian legislation for human consumption in at least one tissue. O. hepsetus (carnivore) showed the highest contamination levels, followed by G. brasiliensis (omnivore) and H. luetkeni (detritivore). The middle-upper segment, which encompasses large urban areas, showed the highest levels of metal contamination in most cases. O. hepsetus showed the highest levels of contamination in muscles for Pb in the middle-upper river segment (7.98?±?3.73; mpc?=?2.0 μg g?1) and for Cr in the upper (5.53?±?0.05; mpc?=?0.10 μg g?1) and middle-upper (4.20?±?0.85; mpc?=?0.10 μg g?1) segments, which indicates that human population should avoid to consume these fishes species from these segments of the Paraíba do Sul river. 相似文献
100.
Nermin Gözükirmizi Kasım Bajroviç Zeliha İpekçi Melih Boydak Tahsin Akalp Korhan Tunçtaner Hülya Balkan Hulki Tanrıyar Mehmet Çalıkoėlu Tijen Oėraş Öznur Özden Mümtaz Tulukçu Turan Tank 《Journal of Forest Research》1998,3(2):123-126
Plant regeneration from 9 clones ofPopulus tremula representing diverse genotypes originated from Turkey, has been studied in different media, such as Murashige and Skoog’s
Medium (MS), Aspen Culture Medium (ACM) and Woody Plant Medium (WPM) with appropriate supplements of growth regulators. Regeneration
efficiency on WPM containing 1 mg/l zeatin using stem explantsin vitro, was higher than on MS and ACM. In this system, the time required for shoot regeneration was 2 weeks, which was shorter by
two weeks than that of previous reports. A strong genotype dependence was observed among the tested nine clones. The regeneration
system, we describe here, did not involve the callus phase and thus was less prone to somaclonal variation. When adventitious
microshoots were cultured on WPM supplemented with 0.5 mg/l or 2 mg/l indole-3-butyric acid (IBA), root formation was obtained after 1 week of culture. Adaptation of regenerated plantletsin vivo was 100%. This system for micropropagation ofPopulus tremula is expected to be suitable for studies on transformation of genes involved in lignin biosynthesis via modification of lignin
content.
This study was a part of the Project No. 62-02-001 TUBITAK-MAN-GMBAE named “Investigations on Biogenetically Develop Poplar
Clones as a Raw Material for Pulp and Paper Industry” and financially supported by General Management of Turkish Pulp and
Paper Mills. 相似文献