Cilt:23 Sayı:03 (2017)

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Borçka Barajı Rezervuarında Yeni Oluşmuş Bir Sediment Birikim Sahasındaki Penetrasyon Direnç Değerlerinin Uzaysal Dağılımı
(Ankara Üniversitesi, 2017-09-01) Turgut, Bülent; Özalp, Mehmet; Öztaş, Taşkın; Ziraat Fakültesi
This study was conducted to analyze vertical and horizontal spatial variability of penetration resistance (PR) in recently deposited sediments at Borçka Dam reservoir. Ninety-one grids with 50 m by 10 m were located and PR was measured to a depth 80 cm by 10 cm increment (8 layers) within each grid. Spatial variation of PR was assessed by geostatistical techniques in all 8 layers. Semivariograms of PR were constructed for all the layers and corresponding kriging maps were built. The PR values were greater in surface layer (0-10 cm) and gradually decreased by depth. Mean PR was greatest (0.747 MPa) in surface layer and lowest (0.413 MPa) in 61-70 cm (layer 7). Results from exploratory statistics and geostatistical analyses showed that the PR values were more variable in surface layer compared to those in deeper layers due to that the surface layer was drier at the sampling and that affected by environmental factors in a greater extent. All the studied layers exhibited differences in spatial variation of PR as sill, nugget, and range values of corresponding semivariograms and kriging-predicted surface maps showed. The shortest geostatistical range (40.8 m) occurred of surface layer while longest (173.3 m) occurred for second layer (11-20 cm). The nugget effect was greatest (44%) in third layer (21-30 cm) while lowest (13%) in the surface layer. The same study may be repeated with more variables to understand mechanisms behind development and extent of spatial variation in these newly deposited sediments.
Çok Kriterli Değerlendirme ile Ankara Güvenç Havzası’nda Erozyon Risk Tahminlenmesi
(Ankara Üniversitesi, 2017-09-01) Turan, İnci; Dengiz, Orhan; Ziraat Fakültesi
The aim of this study is to determine erosion risk classes and to generate their map in Ankara Güvenç Basin using geographic information system (GIS), remote sensing (RS) and statistical approaches with method of multi-criteria decision-making. Basin covers about 17.3 km². In order to determine erosion risk classes, seven criteria (texture, soil depth, precipitation, land use, elevation, slope and vegetation) that influence the occurrence of soil erosion, and sub-criteria of that seven criteria were taken into consideration. 1:25000 scale digital soil map and topographic map were used. In addition to that, Landsat 7 satellite images were used to generate the land use and vegetation cover map. Analytical hierarchy process (AHP) technique was used to determine the priorities of the each criteria while, the Z-score statistical analysis technique was used to determine the priorities of the sub-criteria. Finally, linear combination technique was used to determine classes of erosion risk. According to the obtained results, 45.9% of the basin area was identified as under high erosion risk.
Comparison of Microtubule Organization in Arabidopsis thaliana TUBGFP and MBD-GFP Mutants Exposed to UV-B Radiation
(Ankara Üniversitesi, 2017-09-01) Ma, Dongjing; Chen, Huize; Han, Rong; Ziraat Fakültesi
Microtubule organization was compared between the Arabidopsis thaliana TUB-GFP and MBD-GFP mutants. Plant height and primary root length were measured, and microtubule dynamics were examined by confocal laser scanning microscopy after UV-B radiation to reveal changes in microtubules. Damage caused by UV-B was comparable between transgenic lines and wild-type plants, although transgenic lines were more sensitive to UV-B than the wild-type. Spots and depolymerization of microtubules were detected in both TUB-GFP and MBD-GFP plants; however, MBD-GFP showed better adaptation of changes induced by UV-B treatment. These results indicated that UV-B inhibits the growth and development of transgenic lines, and the inhibitory effects might result from changes in microtubules, as determined by comparison between the TUB-GFP and MBD-GFP lines.
ContacToxicity of Six Plant Extracts to Different Larval Stages of Colorado Potato Beetle (Leptinotarsa decemlineata SAY (Col: Chrysomelidae))
(Ankara Üniversitesi, 2017-09-01) Alkan, Mustafa; Gökçe, Ayhan; Kara, Kenan; Ziraat Fakültesi
Discovery of new eco-friendly methods for insect pest management is very important in integrated pest management program. Contact toxicity of six plant extracts i.e. Acanthus dioscoridis L. (Acanthaceae), Achillea millefolium L. (Asteraceae), Bifora radians Bieb. (Apiaceae), Heracleum platytaenium Boiss (Apiaceae), Humulus lupulus L. (Cannabaceae) and Phlomoides tuberosa (L.) Moench (Lamiaceae), were tested on the 1st to 4th instar larvae of Colorado potato beetle (Leptinotarsa decemlineata Say. (Coleoptera: Chrysomelidae)). The H. platytaenium and H. lupulus extracts were the most effective among the tested extracts, so dose-response bioassay was carried out only with H. lupulus and H. platytaenium against larval stages of Colorado potato beetle. The H. platytaenium extract was the most effective extract with calculated LD50 values 0.126, 0.204, 0.206 and 0.458 μL insect-1, LD90 values were calculated as 0.345, 0.342, 0.402, 0.566 μL insect-1 for 1st, 2nd, 3rd and 4th instars larvae respectively. These results indicate that H. platytaenium and H. lupulus extracts have great potentials as insecticides in the management of larvae of L. decemlineata.
Determination of Genotypic Variation among Sorghum Cultivars for Seed Vigor, Salt and Drought Stresse
(Ankara Üniversitesi, 2017-09-01) Avcı, Süleyman; İleri, Onur; Demirkaya, Mehmet; Ziraat Fakültesi
This study was conducted to determine genotypic variation among sorghum cultivars grown under similar ecological conditions for seed vigor, salt (NaCl) and drought stresses. A seedling survival test was also performed in a pod experiment to investigate genotypic differences in terms of sorghum drought tolerance. In seven sorghum cultivars, seed vigor was determined using electrical conductivity and accelerated ageing tests. Also, germination rate and seedling growth of these cultivars were evaluated under salt and drought stress induced by PEG 6000 at water potentials of 0.0 (distilled water), -1.8, -3.6, -7.2 and -10.8 bar. The results showed that there was a significant difference in seed vigor of sorghum cultivars grown at same ecological conditions. Akdarı produced more vigorous seeds than the other cultivars. The significant relationship between accelerated ageing and laboratory emergence (r= 0.967**), and between electrical conductivity and germination percentage (r= -0.873**) were determined. The suitable tests for germination and emergence potential in sorghum were electrical conductivity and accelerated ageing, respectively. Increasing NaCl and PEG levels inhibited germination and seedling growth. Germination, root length and shoot length were higher, whereas mean germination time was lower, in NaCl solution compared to in PEG solution at the same water potential. In salt, drought and seedling survival tests, Aldarı showed the better performance than the others. It could be concluded that seed vigor is not a reliable indicator of germination performance under salt and drought stress conditions and that genetic differences may play an important role in stress tolerance.
Effect of Cup Size, Seed Characteristics and Angular Speed on the Performance of an Automatic Potato Planter under Laboratory Conditions
(Ankara Üniversitesi, 2017-09-01) Boydaş, Mustafa Gökalp; Ziraat Fakültesi
The seed metering mechanism is the most important unit of potato planters. Accuracy of row plant spacing depends on the ability of the seed metering mechanism. The ability of the seed metering mechanism is directly associated with the constructive and operational variables of the planter. This study was conducted to evaluate the effects of different cups sizes (C1
Pre-harvest Application of ReTain (Aminoethoxyvinylglycine, AVG) Influences Pre-harvest Drop and Fruit Quality of ‘Williams’ Pears
(Ankara Üniversitesi, 2017-09-01) Batur, Sinan; Çetinbaş, Melike; Ziraat Fakültesi
‘Williams’ is the highly quality pear cultivar mostly produced in the Eğirdir region of Turkey. ReTain (15% aminoethoxyvinilglycine, AVG) is a plant growth regulator used to control pre-harvest drop and increase fruit weight and firmness. The objective of this study was to determine the responses of AVG treatments on the preharvest drop and fruit quality of ‘Williams’ pear. Pear trees of the cultivar ‘Williams’ were sprayed 30, 21 and 7 days before commercial harvest (DBH) with AVG, at doses of 100, 125 and 150 mg L-1, and assessed for pre-harvest drop, yield, maturity, delay in harvest, fruit quality, ethylene production and respiration rate at the harvest time. Fruit samples were analyzed for fruit quality parameters which are: fruit width, fruit weight, soluble solids content (SSC), titratable acidity (TA), fruit firmness, fruit colour, fruit macro and micro elements content. Maturation of the 30 and 21 DBH AVG-treated fruits were delayed 3-4 days compared to the 7 DBH AVG-treated and control groups. The pre-harvest drop decreased with all AVG applications by approximately 38-100% in comparison with the control group fruits. AVG treatments increased fruit size (7-10%), fruit weight (26-41%) and fruit firmness (2-16%) of ‘Williams’ pear. AVG application reduce ethylene production and respiration rate and it was found that the applications enhance the ethylene production and respiration rate by approximately (100%) compared to the control fruits on the harvest date. Results of this study indicated that 30 DBH and 21 DBH AVG-treatments at 100 mg L-1 can be recommended for ‘Williams’ pear cultivar on both pre-harvest fruit drop, as well as in harvest date and fruit quality.
Seasonal Carbohydrate Changes in the Leaves of Some Satsuma Cultivars on Different Rootstocks
(Ankara Üniversitesi, 2017-09-01) Yıldız, Ercan; Kqplqnkıran, Mustafa; Demirkeser, Turan Hakan; toplu, Celil; Ziraat Fakültesi
The seasonal changes of carbohydrate content were monitored in the leaves of ‘Okitsu’, ‘Clausellina’, and ‘Silverhill’ satsuma cultivars budded on the sour orange (Citrus aurantium L. var. Yerli), Carrizo and Troyer citranges (Poncirus trifoliata Raf. x Citrus sinensis Osb. var. Troyer and Carrizo) during the 2010 and 2011 seasons. The seasonal changing trends of leaf soluble sugar contents of 3 satsuma cultivars budded on different rootstocks were similar. The sucrose was the most abundant soluble sugar. Carbohydrate contents had a maximum level at dormant period, and remained at low level during summer. In this period, the sharp decrease in leaf total carbohydrate concentration of ‘Okitsu’, ‘Clausellina’ and ‘Silverhill’ occurred in April with a rate of 27.9%, 22.6% and 21.0%, respectively. Accumulation of carbohydrate in leaves generally started after mid summer and continued until the end of year. The rootstocks were found to be not significant for total soluble sugar, starch and total carbohydrate concentration in most of the months. The cultivars had a significant effect on carbohydrate fractions of leaves compared to rootstocks. The scion-rootstock combination was significant on total carbohydrate concentration of leaves in all months investigated.
Selection of Suitable Sites for Small Ruminant Production Using Remote Sensing and the Geographic Information System
(Ankara Üniversitesi, 2017-09-01) Diri, Esin; Ünal, Halil Baki; Ziraat Fakültesi
The aim of this study was to determine the most suitable areas for small ruminant production in the Karaburun area in Izmir province, Turkey. To this purpose, an inquiry model was first developed using remote sensing and a geographic information system. In developing the model, legal and technical factors were taken into consideration, and eight evaluation criteria (distance from settled areas, distance from lakes or similar water sources, distance from protected water catchment basins, distance from wind energy generators, distance from irrigation and drainage canals, slope, aspect-direction of slope-and land use class) and three evaluation classes in relation to these criteria (suitable, conditionally suitable and unsuitable) were planned. Later, the model was used to test the suitability of the study area in general and five sample farms in that area for suitability. According to all of the criteria of evaluation, 3.54% of the 42,707.15 ha study area was found to be suitable for small ruminant production, 2.78% was conditionally suitable, and 93.60% was unsuitable. As for the five sample farms in the study area, none of them was found to be suitable according to all of the evaluation criteria. In addition, suggestions were made for the functionality and effectiveness in use of the geography information inquiry models used in the choice of places for small ruminant production.

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