Yazar "Hocaoglu, Onur" seçeneğine göre listele

Listeleniyor 1 - 9 / 9
  • [ X ]
    Öğe
    ANALYSING GROWTH PATTERNS OF SELECTED TURKISH OAT CULTIVARS USING SIGMOIDAL MODELS
    (Soc Field Crop Sci, 2022) Hocaoglu, Onur
    Increasing popularity of oat was accompanied with the introductions of many new cultivars for the last few decades. The aim of this study was to characterize the growth and developments of Kahraman, Kucukyayla, Yeniceri, Sebat, Otag and Dirilis oat cultivars using sigmoidal growth models. Growth data comprised of weekly observations of dry weights and growth stages with three samplings for two consecutive years. Results indicated that the growing season were the determining factor for the dry matter accumulation until the stem elongation stage since genotype differences became apparent only in the later stages. Sigmoidal growth models were successfully fitted to the growth data, and allowed for further evaluations. Goodness of fit statistics implied that Logistic, Logistic Power and Ratkowsky models were the best fitting growth models to explain dry matter accumulations of oat cultivars. Analysis also showed that Otag, Yeniceri and Sebat cultivars reached the highest dry matter accumulations. Point of inflections on the Logistic models indicated that Kucukyayla and Kahraman were the earliest cultivars in the Marmara region. Comparison of cultivars by using the growth models proved to be informative in terms of understanding the genotypic variation.
  • [ X ]
    Öğe
    Bioethanol potential of switchgrass cultivars for rainfed and irrigated conditions in marginal lands
    (Taylor & Francis Ltd, 2023) Gonulal, Erdal; Hocaoglu, Onur
    Bioethanol is a climate-friendly alternative to conventional energy sources. This study was conducted to determine bioenergy potential of switchgrass cultivation in Central Anatolia where water scarcity limits the agricultural production. Field trials were conducted in a randomized blocks design with three replications under irrigated and rainfed conditions for three growing seasons (2019, 2020 and 2021). Biomass yield (BY), theoretical cellulosic ethanol yield (TEY), theoretical ethanol potential (TEP) with several quality parameters of 10 switchgrass cultivars were evaluated. Highest BY averages were obtained from Boomaster cultivar with 5.28 (rainfed) and 18.45 t ha-1 (irrigated) when Dacotah had the lowest BY averages of 1.55 (rainfed) and 5.29 t ha-1 (irrigated). ANOVA and Genotype Trait Biplot results revealed higher BY, TEY and TEP with lower ADF, NDF and ADL of lowland ecotype cultivars. Lowland ecotypes provided superior results in both rainfed and irrigated conditions with a higher response to irrigation. TEY of switchgrass were found as positively associated with BY, plant height and stem weight which could be used as indicators of TEY for genotype selection. In conclusion, lowland ecotype cultivars of switchgrass were recommended for bioethanol production in water limited environments.
  • [ X ]
    Öğe
    BIPLOT ANALYSIS OF LEAF RUST RESISTANCE IN PURE LINES SELECTED FROM EASTERN ANATOLIAN BREAD WHEAT LANDRACES OF TURKEY
    (Soc Field Crop Sci, 2017) Akcura, Mevlut; Akan, Kadir; Hocaoglu, Onur
    The present research was conducted to determine the reactions of 42 pure lines selected from bread wheat landraces of Eastern Anatolia, Turkey, against the leaf rust (Puccinia triticina) disease under field conditions across 7 environments. G (Genotype), GE (Genotype Environment) biplot analysis method was used to determine the reactions of landraces against leaf rust disease. GGE-biplot graph created to assess leaf rust disease was explained a 78.12% of total variation. While E3 and E2 constituted the first and second mega environments respectively, the other four environments constituted the third and fourth mega environments. The lowest PC1 values and PC2 values close to 0.0 explaining the resistance of pure lines to leaf rust at best in the biplot. Reactions of landraces varied based on their distance from the Average Environment Axis (AEA). While the pure lines with the same or similar reactions in 7 experimental environments fell close to the axis, ones with different reactions in one or more environments were relatively distant. The pure lines of EA15 and EA19 were identified as the most resistant and stable genotypes in all environments when EA42 and EA41 were the most susceptible/stable genotypes in all environments. Pure lines that were resistant or moderately resistant at all seven tested environments should be useful for breeding wheat cultivars with resistance to leaf rust in Turkey.
  • [ X ]
    Öğe
    Callus induction of mature wheat embryos treated with sodium hypochloride
    (Elsevier Science Bv, 2018) Turkmen, Onur Sinan; Egesel, Cem Omer; Hocaoglu, Onur; Fedakar, Serpil Orhan
    [Anstract Not Available]
  • [ X ]
    Öğe
    Changes in the Grain Element Contents of Durum Wheat Varieties of Turkey Registered between 1967-2010
    (Taylor & Francis Inc, 2020) Hocaoglu, Onur; Akcura, Mevlut; Kaplan, Mahmut
    While grain yield is the main consideration in developing new cultivars, grain element compositions were also affected by the process of plant breeding. This research aims to evaluate genotypic variation in thousand kernel weights (TKW), percentages of yellowberry kernels (PYK), boron, calcium, copper, iron, potassium, magnesium, manganese, sodium, nickel, phosphorus, sulfur, and zinc contents in the grains of 29 Turkish durum wheat cultivars (triticum durum) released between 1967-2010. Element contents of grain samples are determined with inductively coupled plasma optical emission spectrometry (ICP-OES). Results of 2 years of field trials indicated significant variation between cultivars in terms of all investigated traits (p < .01). TKW of Turkish durum cultivars along with calcium, copper, and sulfur contents are found to be consistently increasing over time with positive correlations to each other. On the other hand, boron and zinc contents of the grain remained unaffected during the process of plant breeding when sodium contents decreased. We suggest that selecting for new germplasm to increase iron, zinc, and phosphorus contents of durum grain will contribute to the nutritional value of its products.
  • [ X ]
    Öğe
    DECISION MAKING ON NITROGEN MANAGEMENT OF OAT (AVENA SATIVA) USING GRAIN YIELD POTENTIAL AND NITROGEN USE EFFICIENCY
    (Soc Field Crop Sci, 2020) Hocaoglu, Onur; Akcura, Mevlut
    While oat is a major cold-climate cereal in Marmara region of Turkey, little is known about the nitrogen use efficiencies (NUE) of Turkish oat cultivars. This research aims to evaluate NUE, grain yield, and several agronomic traits of 5 oat cultivars in 5 nitrogen applications doses. Field trials were conducted in the Canakkale, Turkey for two growing seasons where NUE, grain yield, plant height, panicle length, grain number per panicle, and grain weight per panicle were determined. Results of variance analysis indicated statistical significance for year, genotype, N dose, and Genotype x N dose effects for all traits. New oat cultivars (Kahraman, Yeniceri, and Sebat) were found to have higher grain yield and NUE compared to the older cultivars (Chekota and Seydisehir). Grain yield response of each cultivar to the increasing N levels were further investigated with regression analysis and Princial Component Analysis (PCA) Biplot. Results suggested that Kahraman has the highest grain yield potential when Sebat and Yeniceri can be recommended for the higher N doses. We conclude that oat breeding efforts of the last decade may have contributed to higher NUE along with improving grain yield of oat cultivars in Turkey.
  • [ X ]
    Öğe
    Evaluating Scald Reactions of Some Turkish Barley (Hordeum vulgare L.) Varieties Using GGE Biplot Analysis
    (Mdpi, 2023) Akan, Kadir; Cat, Ahmet; Hocaoglu, Onur; Tekin, Mehmet
    Scald caused by the fungal pathogen Rhynchosporium commune is a significant foliar disease affecting barley production on a global scale, and it leads to substantial reductions in both yield and quality of barley. In the current study, the reactions of 40 Turkish barley (Hordeum vulgare L.) varieties to scald were evaluated under natural conditions in canakkale and Kirsehir in 2021-2022, and Antalya and Siirt locations in 2022-2023 growing seasons. Field trials were conducted according to randomized block design with three replications in each year; the spore concentration was 1 x 10(6) spores per mL, and it was applied to the varieties three times at different growth stages. The reactions of barley varieties were assessed using a newly designed two-digit scale ranging from 11 to 99. Based on their scale values, the varieties were categorized as immune (0), resistant (11-35), moderately resistant (36-55), moderately susceptible (56-75), and susceptible (76-99). In addition, genotype plus genotype-by-environment (GGE) interactions of scale values were analyzed through GGE Biplot and explained 97.65% of the total variation. The ranking of genotypes based on scale groups generally showed consistency with GGE Biplot results, but GGE Biplot offered a more detailed classification, especially for moderately susceptible varieties. The relationship between the two methods indicated the relative stability of variety reactions, as GGE Biplot analysis also considered genotype stability. In conclusion, the use of the newly developed scale for evaluating scald reactions in barley gives reliable results. In addition, identified resistant varieties can serve as valuable genetic resources for further breeding studies.
  • [ X ]
    Öğe
    EVALUATION OF DRY MATTER ACCUMULATION IN TRITICALE BY DIFFERENT SIGMOIDAL GROWTH MODELS IN WEST ANATOLIA OF TURKEY
    (Serbian Genetics Soc, 2018) Hocaoglu, Onur; Coskun, Yalcin
    Monitoring biological growth of field crops is important for planning and timing agricultural practices. In order to assess biological growth pattern of dry matter accumulation in triticale Egeyildizi triticale variety were grown in canakkale conditions in 2012-2013 and 2013-2014 growing seasons with continuous plant samplings from seedling emergence until seed maturation. Gompertz, Logistic, Logistic Power and Richards growth models are fitted to actual growth data and their predictions were compared. Results suggested that all sigmoidal growth models successfully explained triticale dry matter accumulation over 98 % R-2 values and low mean square errors, Richards model fitted best for both years with an R-2 value over 99 %. Dry matter accumulation were also investigated as a result of average temperature, precipitation, growth degree days and cumulative growth degree days with stepwise regression. Rresults indicated that average weather temperature had a similar pattern across both growing seasons and had a major influence on dry matter accumulation. Since Richards sigmoidal growth model may be adequately described growth pattern of triticale by generally high R-2 with lower Mean Square Error (MSE) values.
  • [ X ]
    Öğe
    Modelling the Effect of Irrigation Deficit on Maize Growth with Logistic Regression
    (Taylor & Francis Inc, 2023) Hocaoglu, Onur; Gonulal, Erdal; Akcura, Mevlut
    This research is conducted to model the limiting effects of irrigation deficit on maize growth which is a major challenge in dry areas. Field trials were conducted in completely randomized block design with three replications in Konya region (Turkey) during 2020 and 2021 growing seasons between May and August. Dry matter (DM) increase of maize was assessed on weekly intervals under four irrigation treatments, configured as %100, 75, 50 and 25 of the field capacity. Curve fitting with Logistic regression model demonstrated gradual decreases of maximum DM (from 496.331 to 254.119 g) and maximum growth rate (49,95 to 29,47 g/weeks) in average due to irrigation deficit when accurately modeling the DM accumulation with the varying R-2 values between 0.979 and 0.995. Results of logistic regression curves and IWUE suggested that even 25% restriction of irrigation water caused an average of %25.5 decrease on DM when 50% and more restriction could be associated with water stress. Additionally, irrigation water use efficiency (IWUE) was increased after the maximum acceleration point (MAP) which coincided with tasseling stage and inflection point (IP) where growth rate reaches to maximum, indicating that these periods were critical for maize in terms of preventing water deficiency.