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Bitkilerde Rizosferden Demir Alım Mekanizmaları Texte intégral
2018
Emre Aksoy | Bayram Ali Yerlikaya | Sefa Ayten | Buasimuhan Abudureyimu
Demir, toprakta en çok bulunan elementlerden bir tanesi olmasına karşın çözünürlüğü alkali topraklarda düşüktür. Dolayısıyla bu tür topraklarda yetişen bitkiler sürekli demir eksikliği stresine maruz kalırlar. Dünyadaki tarım arazilerin üçte biri bu tür topraklardan oluştuğundan dolayı tedavi edilemeyen demir eksikliği tarımsal üretimi kısıtlar. Bitkilerde gözlenen demir eksikliğinin tedavisinde farklı demir gübreleri kullanılmaktadır. Ancak, bu gübrelerin kullanımı üretim maliyetlerini artırmaktadır. Maliyetlerin azaltılabilmesi için bitkilerin toprakta bulunan demiri en etkin biçimde kullanabilmeleri gerekir. Bunun için de ilk olarak bitkilerin topraktaki demiri nasıl kök içerisine aldıklarının incelenmesi gerekmektedir. Son otuz yılda yapılan çalışmalarda farklı bitki gruplarının 3 farklı demir alım mekanizması kullandıkları keşfedilmiştir. Bu derlemenin amacı, demirin kök içerisine alımından sorumlu taşıyıcılar ile bu taşıyıcılar hakkındaki güncel gelişmelerden bahsetmektir.
Afficher plus [+] Moins [-]Effects of Arbuscular Mycorrhizal Fungi (AMF) on Heavy Metal and Salt Stress Texte intégral
2018
Aydın Atakan | Hülya Özgönen Özkaya | Oktay Erdoğan
The Arbuscular mycorrhizal fungi (AMF) are microorganisms that live symbiotically with plant roots and have many benefits to soil and plants. In this study, some effects of AMF which are known to be soil and plant beneficial, have been evaluated and solution proposals have been put forward against heavy metal and salinity stress in the soil. Salt accumulation and high concentrations of heavy metal in the soil affects negatively the microbial diversity and activity. Removal of salt acumulation and heavy metal from contaminated soil by chemical and physical methods is both very expensive and ineffective. Therefore, AMF are important for alleviating the heavy metal and salt stress in plants. AMF can alter plant physiol¬ogy and root morphology, increase the uptake of nutrients and water from the soil through an extensive hyphal network, decrease the use of chemical fertilizer, interact with other soil microorganisms plant growth promoting, induce of some resistance parameters in the plants and produce the glomalin which develops the properties and structure of soil. AMF are eco-friendly solutions according to traditional methods and the use of suitable plant-fungi combinations increases the chances of success of these applications.
Afficher plus [+] Moins [-]Estimation of Soil Losses in a Slope Area of Tokat Province through USLE and WEPP Model Texte intégral
2018
Saniye Demir | İrfan Oğuz | Erhan Özer
Tokat is one of the developing provinces in terms of urbanism. Therefore, the land use changes city-wide which closely affects soil erosion. Numerical estimation of soil erosion is very important to prevent soil losses. In this study, USLE and WEPP Hillslope model were used to estimate the long-term soil losses in a slope area which used to be a pasture land and then turned into a fruit orchard in Büyükbeybağı area of Tokat province. Erosion sensitivity of the soil in the slope area was detected to be very low. Erosivity value of the area is low, soil is resistant to erosion due to pasture land use type and fruit orchard use type does not require intense soil cultivation practices. For all these reasons, both estimation technologies estimated soil losses of the land to be low.
Afficher plus [+] Moins [-]Consumers’ Subjective and Objective Knowledge Levels About Genetically Modified Foods: Case Study of Hatay City Texte intégral
2018
Ahmet Duran Çelik | Erdal Dağıstan
The relationship between an individual’s actual knowledge and their self assessed knowledge about an issue is an important factor on consumer’s behaviour. The effect of the knowledge factor on consumer decision making is evaluated by two approaches which are objective (real knowledge) and subjective (self assessed) knowledge. In certain studies it was found that in some situations consumers believe they know more than they actually do about a topic; and they may make their decisions based upon the knowledge they assume is correct, whether it is true or not. This study aimed at determining the relationship between the objective and subjective knowledge about GM foods of consumers who live in the Hatay city centre. According to the research results; even though around 70% of the consumers thought that their knowledge about GM foods were ‘’enough, or relatively enough’’, correct response ratios of the four questions that were based on specific knowledge were quite low. In other words, consumers were overconfident about their knowledge of GM foods. Also, there was no correlation found between consumer’s purchase intention and knowledge level.
Afficher plus [+] Moins [-]The Amino Acid Composition of Blue Swimming Crab (Portunus Segnis, Forskal, 1775) from The North Eastern Mediterranean Sea of Turkey Texte intégral
2018
Engin Artar | İlkan Ali Olgunoğlu
This study was carried out to detect the content of amino acid in female and male specimens of blue swimming crab (Portunus segnis) obtained from (including 12 male crab and also 12 female crab) North Eastern Mediterranean Sea, Turkey. The protein was identified as 17.63% and 18.13% for female and male crab respevtively. Totally 9 essential amino acids were recorded in the present study. Lysine and leucine constituted the highest essential amino acid (EAA) concentrations in P. segnis. This species was found to be in good score in terms of the level of EAA and the EAA/Non-EAA ratios when compared with other economical crab species.
Afficher plus [+] Moins [-]The Way of Yield Increasing and Cost Reducing in Agriculture: Smart Irrigation and Fertigation Texte intégral
2018
Muhammed Karaşahin | Özgür Dündar | Ahmet Samancı
The plants can only use the around 50% of the applied nitrogenous fertilizer. It has been observed that the dynamic fertigation applications help to improve the fertilizer effectiveness. In the dynamic fertigation approach, water and plant nutritional elements are calculated and determined according to the plant dry matter generation rate and root volume. Smart agriculture is an knowledge based decision making approach established upon quantification and observations of the changes in each level of production. With this system, saving can be provided by only supplying the plant’s daily need of water and fertilizer and preventing the excess irrigation and fertilizing, so yield increase can be achieved by keeping away the plants from the stress conditions. Agricultural production can be increased five times by irrigation but shortening in water sources and decrease in quality reasoned by fast growing are restricted of irrigation which is the main user of freshwater sources. Increasing the water and fertilizer effectiveness with the smart irrigation techniques which can save water and fertilization management applications are the essential strategies to be able to reach the yield increase in order to supply the growing food needs of developing population and help to minimize the environmental damage. In the study, the researches and applications related to smart irrigation and fertilization were tried to be included in a wide scope and tried to keep a light to obtain higher yield with less water and fertilizer use in agriculture.
Afficher plus [+] Moins [-]Biological Activities of Stem, Leaves and Essential Oil of Cedrus deodara from District Poonch, Rawalakot Azad Kashmir, Pakistan Texte intégral
2018
Tahir Zaman | Mubasher Sabir Syed | Sadaf Isfaq | Muhammad Sarfraz Khan
Cedrus deodara (Roxb. ex D. Don) Loudon, is a high value medicinal plant found in flora of Poonch part of Himalayan region. The present study was conducted to determine and compare the antioxidant activity, quantification of phenolics and flavonoids, chelating ability, biofilm inhibition, thrombolytic activity and cytotoxicity of the stem, leaves of crudes extracts and essential oil. It can be claimed that that all parts of C. deodara including its essential oil is a rich source of phytochemicals that exhibited high quantity of phenolics ranged from (49.76±0.22 GAE to 60.36±0.44GAE mg/g) and flavonoids ranged from (4.78±0.61mg/g to 6.62±0.45 mg/g)but also exhibited antioxidant, metal chelating agent ability, antibacterial potential ranged from (35.59±0.50 to 61.61±0.61%)and thrombolytic activities ranged from (22.86±0.7 to 32. 64±0.5 %)with minimal toxicity ranged from (0.40±0.35 to 3.73±0.23%). Further studies are required to determine the bioactive compounds and bioactivity of plant extracts and fractions.
Afficher plus [+] Moins [-]Isolation of Anti-Escherichia coli O157:H7 Bacteriophages and Determination of Their Host Ranges Texte intégral
2018
Zeliha Yıldırım | Tuba Sakin | Fatma Çoban
The aim of this study was to isolate, purify and determine host ranges of bacteriophages infecting Escherichia coli O157:H7 from different environment such as river/stream water, sewage, raw food, animal troughs, wastewaters of food processing plants, slaughterhouse and fish farms. For screening of E. coli O157:H7 bacteriophages, 92 samples were used. It was found that in respect to anti-E. coli O157:H7 bacteriophages, food processing wastewaters, sewage and slaughterhouse wastewaters are the richest sources, and streams, troughs and fisheries wastewater are rich in the middle, and raw foods were the poorest source. A total of 37 phages were isolated and purified. The phages counts of the purified samples were changed among 30×103 - 34×108 PFU/mL. The isolated phages were generally infective against E. coli O157:H7 and E. coli strains and 81.08% of the phages (30 out of 37) formed clear plaques and were capable to lyse at least 1 out of 5 E. coli O157:H7 strains. In addition to E. coli, some phages were capable to infect some Salmonella enterica serovars. This results show that inhibitor spectra of the phages were wide.
Afficher plus [+] Moins [-]Semi-Arid Plantation by Anatolian Black Pine and Its Effects on Soil Erosion and Soil Properties Texte intégral
2018
Sezgin Hacisalihoglu
In this study, the effects of Anatolian Black pine [(Pinus nigra Arn. subsp. pallasiana (Lamb.) Holmboe] plantation on hydro-physical soil properties and soil loss were investigated. This study was carried out on the afforestation field of Anatolian Black Pine in the Gölbaşı district of Ankara province, which is included in the arid and semi-arid regions. Totally 48 soil sample in two soil depth level (0-20cm, 20-50cm) were collected from forest (36 soil sample) and barren (control) area (12 soil sample). Hydro-physically important soil properties were analysed [Sand (%), Silt (%), Clay (%), Organic Matter (%), pH, Field Capacity (%), Wilting Point (%), Saturation (%), Available Water Holding Capacity (cm/cm) Saturated Hydraulic Conductivity (cm/hr), Bulk Density (gr/cm3)]. And soil loss in a unit area by using ABAG (Allgemeine Boden Abtrags Gleichung) model was estimated. Soil properties and soil loss amount relations among the land use group were determined. Topsoil (0-20cm) and subsoil (20-50cm) properties except subsoil organic matter were significantly affected by land use group. Finally, Significant changes were found for annual soil loss amounts in a unit area. Avarage annual soil loss in planted area was found approximately 5.5 times less than barren area at 0-50 cm soil depth. Vegetation factor (C) which is one of the most important components of the soil loss equation, has been significantly affected by afforestation in a short period of 40 years and thus it was a variable to reduce to soil loss.
Afficher plus [+] Moins [-]Determination of Anionic Detergent Concentration of Karasu Stream in Sinop (Turkey) Texte intégral
2018
Ayşe Gündoğdu | Erdi Gültepe | Uğur Çarlı
The study was achieved between May 2014 and April 2015 at the Karasu Creek located in the province of Sinop. It was conducted to determine anionic detergent pollution and some physicochemical properties (pH, temperature, conductivity, salinity, dissolved oxygen, total hardness, chemical oxygen demand, phosphate PO4-3, total nitrogen). The anionic detergent concentration of the stations was determined on a monthly basis. Seasonally averaged values of the anionic detergent was measured as the highest value in the autumn season. The lowest values of anionic detergent were found in stations in winter and spring. The increase in the concentration of anionic detergent is caused by population growth in residential areas, increased agricultural activities and rains, and that chemicals move to riverbed from terrestrial areas with rain water.
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