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Partial Purification and Characterization of Microbial Phytases from Pseudomonas chlororaphis, Bacillus megaterium, and Agrobacterium radiobacter 全文
2025
Merve Şenol Kotan
Phytases are enzymes that hydrolyze the phosphate groups in phytic acid to release soluble phosphate. Among phytases, microbial phytases are preferred due to their high activity, low cost, and environmentally friendly properties. In this study, microbial phytases were obtained from Pseudomonas chlororaphis C37-A, Bacillus megaterium M-3, and Agrobacterium radiobacter A-16 isolates. The phytase enzymes were partially purified using ammonium sulfate precipitation, and their optimum pH and temperature conditions were subsequently determined The most suitable ammonium sulfate precipitation range in the partial purification process was determined as 60-80% for isolate M-3 and 40-60% for isolates C37-A and A-16.The specific activities and purification folds of the enzymes in these precipitation ranges were measured as 34.28EU/mg and 3.94 for M-3, 27.25EU/mg and 1.91 for C37-A, and 23.24EU/mg and 2.11 for A-16, respectively. SDS-PAGE analysis showed that the molecular weights of the enzymes were approximately 45 kDa. When tested for enzymatic performance, phytase obtained from P. chlororaphis C37-A showed its highest activity at 50°C and pH 8.0, while B. megaterium M-3 showed the best activity at 50°C and pH 6.0. The enzyme obtained from A. radiobacter A-16 reached the highest activity at 30°C and pH 6.0. These findings suggest that the phytase enzyme from P. chlororaphis prefers slightly alkaline conditions, whereas phytases from B. megaterium and A. radiobacter function better in mildly acidic environments. Overall, the varying environmental tolerances of these isolates support their potential use in developing microbial biofertilizers, especially for soils that are poor in phosphorus.
显示更多 [+] 显示较少 [-]Evaluating the Agronomic and Economic Yield of Rice: An Effective Way for Delivering Extension Service 全文
2025
Adane Melak Beyene
Over the past decade, Africa has experienced the fastest-growing demand for rice globally, underscoring the crop’s significant economic and social importance. Despite this surge in demand, rice yields across the continent remain among the lowest compared to other major rice-producing regions, leading to a heavy reliance on imports. Enhancing rice productivity is therefore critical and can be achieved by optimizing key agronomic practices, such as planting density and seedling age. This study aims to identify the appropriate seedling age and optimal planting density for the NERICA 10 rice variety to maximize grain and straw yields while ensuring high net profitability. The experiment was conducted using a factorial randomized block design with three replications. Seedling age of 21 and 28 days after sowing (DAS) and planting density of 14.5, 20.0, and 25.6 hills/m2 were used as factors. Plant length, stem number, leaf color, heading date, paddy yield, yield components, and straw yield were measured. Data were analyzed using Microsoft Excel and JMP (ver.14.0). The ANOVA result revealed that, there was no interaction effects between seeding age and planting density on growth, paddy yield and yield components, straw yield, and harvest index. However, seedling age had significant effect on plant length, stem number/m2 and headings; while planting density had a significant effect on the number of stems/m2, panicles/m2, and spikelets/panicle. Number of panicles/m2 had also a strong and significant relationship with paddy yield. In paddy yield estimated from yield components, the combination of 28-day-old seedlings with a planting density of 25.6 hills/m² (A2D3) had a 5.4% advantage over the combination of 21-day-old seedlings with a planting density of 20.0 hills/m² (A1D2). However, in Tsubo-Gari sampling, A1D2 outperformed in paddy and straw yield that reached up to 28.3% and 30.2%, respectively, and gave net benefit advantage between 978.35 to 2329.33 USD over alternatives. Applying A1D2 (20.0 hills/m2) decreased seedling cost/ha by 198.7 USD, increased milled rice by 0.98 ton/ha and net profit by 1982.05 USD over A2D3 (25.6 hills/m2). Therefore, A1D2 is recommended as the most effective treatment for optimizing both yield and profitability.
显示更多 [+] 显示较少 [-]Assessment of Storage Insect Pests, Methods and Management Practices for Rice (Oryza sativa L.) in Fogera, Northwestern Ethiopia 全文
2025
Esuyawkal Demis | Abaynew Jemal | Tesfaye Melak
Storage pests are a significant factor contributing to rice crop losses, adversely affecting both the quantity and quality of stored rice. This study was carried out to assess the current status of storage insect pests, storage methods, and management practices in Fogera district, Ethiopia, during the 2022 cropping season. The assessment was conducted based on interviews, visiting the individual households, and collecting a representative sample of rice grains from each store among 200 randomly selected farmer households. Data on the socio-economic characteristics, storage structures, durations of rice storage, pest management practices, relative abundance, grain damage, weight loss, and germination percentage were collected and analyzed using descriptive statistics. The result of the study showed that rice weevil (Sitophilus oryzae), lesser grain borer (Rhyzopertha dominica), red flour beetle (Tribolium castaneum), and angoumois grain moth (Sitotroga cerealella) insect pests were found in the surveyed areas. Among these, rice weevil and lesser grain borer predominantly occurred, and the majority of the respondents perceived them as the most common and damaging pests of rice. Most farmers used traditional storage structures like Gota (32%), Shirfa (27%), polypropylene bags (25%), and fertilizer bags (12%) for storing rice, which were susceptible to insect pest infestations, resulting in 2.26% grain damage. Farmers applied various storage insect pest control methods, including physical, chemical, and cultural practices, with chemical (29%) being the most commonly used. They repeatedly use insecticides that pose risks to both the environment and human health. Therefore, the study recommended the adoption of improved storage technologies to protect grains from pests, minimize insecticide use, and preserve grain quality. Additionally, training on effective storage methods, pest management, and healthy rice preparation is essential. These findings serve as a foundation for developing sustainable pest management methods in the study area, ultimately improving food security and farmer livelihoods.
显示更多 [+] 显示较少 [-]Comparative Estimation Models of Egg Albumen Index in Atak-S Hens with Ridge and Principal Component Regression Methods 全文
2025
İsmail Gök | Kadriye Kurşun
In this study, multiple regression analysis was used to estimate the relationships between egg albumen index and external egg quality traits in Atak-S hens. Egg albumen index was selected as the dependent variable, while egg weight, width, length, shape index, and Haugh unit were selected as independent variables. While the overall model fit was high in the multiple regression analysis, multicollinearity problem were identified among the independent variables. This could affect the model's predictive accuracy, and this problem must be resolved to obtain reliable results. For this purpose, Ridge and Principal Component Regression methods, frequently used in the literature, were applied. In the analyses, the models obtained using the variables used to estimate albumen index and external quality parameters were found to be statistically significant (P<0.05), and the goodness-of-fit coefficient of the models was determined to be R² = 0.88. It was determined that the Ridge regression method yielded slightly more stable results in terms of predictive power, but the Principal Component Regression method provided an advantage in terms of increasing interpretability. These results demonstrate that Ridge and Principal Component Regression methods are robust alternatives that can be used confidently in data structures containing multicollinearity. The findings demonstrate that these methods can be successfully used in poultry breeding and selection studies, yielding more reliable and accurate results. Furthermore, it is clear that these methods will contribute to the development of more effective and robust models in studies on egg quality and productivity.
显示更多 [+] 显示较少 [-]Value in Transition: Spatial, Temporal, and Pandemic-Driven Dynamics in Türkiye’s Agricultural Trade 全文
2025
Hüseyin Tayyar Güldal
This study analyzes Türkiye’s fresh fruit and vegetable exports over the period 2010–2020, focusing on product-level, spatial, and temporal dynamics. Using disaggregated data from the Turkish Exporters Assembly, the research combines time series analysis, spatial visualization techniques, and a series of fixed effects panel data models estimated separately for each product. By incorporating a year-specific dummy variable for 2020, the models capture the average price dynamics over time and allow for the identification of the COVID-19 pandemic’s distinct impact on each product’s Free on Board (FOB) export value. The findings indicate that high-value-added products have become more diversified, with the Aegean and Mediterranean regions standing out as key contributors to total export value due to their infrastructural capacity and crop diversity. The results further reveal that the pandemic triggered statistically significant price increases for several products including pear, strawberry, apple, date, fig, peach, and grape suggesting a shift in international demand towards health-promoting and durable fresh produce. Overall, the study underscores the need for export strategies that emphasize not only volume expansion but also unit value growth, regional competitiveness, and product-level resilience to global shocks.
显示更多 [+] 显示较少 [-]Recent Patterns of Temperature and Rainfall Variation in a Tropical Rainforest Location 全文
2025
Chris Adegoke Fayose
Temperature and rainfall are critical variables influencing crop production in tropical regions such as Ile-Ife. Understanding recent trends in these variables is essential for helping farmers adapt to the impacts of climate change. This study analyzed 12 years (2011–2022) of daily air temperature and rainfall data from the automatic weather stations (AWS) at Obafemi Awolowo University (OAU), Ile-Ife, to identify trends and potential evidence of climate change. Summary and inferential statistical methods, including bar and line charts, mean, standard error of the mean, range, and regression analysis, were used for data analysis. Results showed rainfall pattern that has become more erratic with higher interannual variability, delayed onset, increased concentration in fewer months, and frequent extreme events, all of which indicate the intensifying impacts of climate change on local agriculture. The mean annual rainfall and range were 1505 mm and 675 mm to 2829 mm, respectively, with a declining trend (b = -45.62 mm) and a significant R² value of 0.48. Mean air temperature ranged from 25.2°C to 28.2°C with a declining trend over the past decade, and reduction in maximum annual temperature in contrast with earlier reports and global warming projections. Findings suggest that climate change at this location is characterized more by concentrated high rainfall events between June and August rather than a reduction in total annual rainfall or a significant temperature increase.
显示更多 [+] 显示较少 [-]Comparative Effects of Lactose-Free and Regular Kefir on Lifespan of Drosophila Melanogaster 全文
2025
Mehmet Fidan
This study investigated the effects of lactose-free and regular kefir on Drosophila melanogaster lifespan, by applying four doses (5%, 10%, 15%, 20%) to assess their impact on aging through mathematical modeling. We hypothesized that kefir's probiotic content could extend lifespan through its bioactive compounds, with the observed differences potentially attributable to lactose content and dosage. Wild-type flies were divided into groups: a control group fed with a standard diet (SDB), and groups fed regular or lactose-free kefir at varying concentrations. Each group comprised 100 male and 100 female flies, with three replicates, maintained at 25°C and 60% humidity. Daily survival data were collected and analyzed using the Gompertz model to evaluate lifespan and aging rates. Results showed that regular 15% kefir increased average lifespan from 61.2 to 68.2 days for females, and 63.5 to 70.0 days for males, while lactose-free kefir at the same dose extended it to 72.4 and 73.9 days, respectively. Aging rates decreased most significantly at 15% lactose-free kefir, indicating slower aging. However, at 20%, lifespan gains diminished, indicating a complex dose-response relationship that warrants further investigation. These findings suggest kefir's anti-aging potential, with lactose-free kefir showing greater efficacy (18.3% increase in females and 16.4% increase in males), and highlight the importance of dose optimization in aging research.
显示更多 [+] 显示较少 [-]Optimization of Process Variables for Extruded Snacks from Acha-Peanut Blends Separately Enriched with Carrot and Orange-Fleshed Sweet Potato Flours 全文
2025
Stephen Sule | Gabriel Ifeanyi Okafor | Chigozie Francis Okoyeuzu | Godwin Ekojah Onah
Extruded foods are shaped, cooked products made by forcing ingredients through a high-temperature, high-pressure extruder. This study optimized extrusion conditions for snacks made from acha-peanut blends enriched with carrot and orange-fleshed sweet potato (OFSP) flours. Using material balancing, four formulations were developed to meet a 19 g/day target: A (100% acha), AP (81.08% acha + 18.92% peanut), APC (64.21% acha + 20.64% peanut + 15.15% carrot), and APO (64.55% acha + 20.74% peanut + 14.71% OFSP). A two-level factorial Central Composite Design was employed to study the influence of moisture (14–22%) and temperature (100–120 °C) on the physical characteristics and acceptability of the snacks. Results indicated that 100% acha (A) snacks had the largest diameters (13.3–14.9 mm) and lowest densities (apparent: 0.41–0.54 g/ml; bulk: 0.13–0.17 g/ml), leading to high porosity (0.68–0.80), expansion ratios (4.43–4.97), and overall acceptability (6.85–8.25). AP snacks exhibited slightly smaller diameters (12.7–13.9 mm), higher densities (apparent: 0.46–0.60 g/ml; bulk: 0.13–0.21 g/ml), moderate expansion ratios (4.23–4.67), and acceptability scores (7.50–8.00). APC snacks had increased densities (apparent: 0.54–0.60 g/ml; bulk: 0.16–0.28 g/ml), smaller diameters (9.5–11.7 mm), lower porosity (0.53–0.71), and reduced expansion ratios (3.17–3.90), with acceptability scores (6.55–8.15). APO snacks yielded the densest snacks (apparent: 0.60–0.71 g/ml; bulk: 0.29–0.41 g/ml) with the smallest diameters (7.9–9.0 mm), lowest expansion ratios (2.63–3.00), and the least acceptability (6.50–8.10). Regression analysis indicated that higher moisture content decreased density and acceptability, while increased temperature enhanced porosity and expansion especially in AP and APO snacks. Optimal extrusion conditions were identified as: A (14.57% moisture, 113.33 °C), AP (19.90%, 120 °C), APC (18.93%, 118.79 °C), and APO (17.72%, 113.94 °C). Further studies are suggested to evaluate the quality and shelf-life stability of the optimized products.
显示更多 [+] 显示较少 [-]Prevalence and associated risk factors of anaplasmosis in goats at Chattogram district, Bangladesh 全文
2025
Bijoy Chowdhury | Bhajon Chandra Das | Dibyendu Biswas
Anaplasmosis, a vector-borne haemoparasitic disease, poses a significant threat to animal health. This study investigated the prevalence and associated risk factors of anaplasmosis in goats within the Chattogram district of Bangladesh. The research was conducted at the SA Quadery Teaching Veterinary Hospital (SAQTVH), Chattogram Veterinary and Animal Sciences University (CVASU), involving observations of 202 goats. Blood samples were collected from the ear veins of 44 goats. Thin blood smears were prepared, stained with Giemsa, and examined under a microscope. Statistical analysis was performed using Chi-square tests in SPSS Statistics version 26. The study found that goat rearing systems significantly influenced infection rates (P < 0.05). Anaplasmosis was more prevalent in goats displaying pale mucous membranes and symptoms such as fever or weakness (P < 0.05). To mitigate the disease, strategic control measures, including vector reduction and routine health monitoring, are recommended.
显示更多 [+] 显示较少 [-]Growth Performance, Body Measurements and Live Weight Estimation of Tülü (Bactrian × Dromedary F1) Calves from Birth to Six Months of Age 全文
2025
Atakan Koç | Alkan Çağlı
A hybrid camel Tülü (Bactrian male x Dromedary female F1) males are preferred in camel wrestling, which is a culture unique to Anatolia. In this study, changes of live weight (LW), daily weight gain (DWG), and body measurements (BMs) of Tülü calves in the first 6 months of age in a farm in Aydın province, Türkiye, were determined as well as developing equations to estimate LW from body measurements. Tülü calves average birth weight (BW) was 34.7±1.80 kg and reached 175.3±3.38 kg at the age of 6 months with a 0.768±0.03 kg DWG during this time. Although the monthly total weight gains and monthly DWG averages of the calves in the first 6 months were similar, the changes in monthly LW and BMs were statistically significant (P<0.01). Abdominal girth (AG) alone can be used to predict LW in the analysis performed to estimate LW from body measurements by stepwise regression (R²=95.62%). In conclusion, Tülü calves had relatively high growth rate in their first six months of age, and unlike other livestock species, instead of hearth girth (HG), AG that includes the hump can be used to estimate LW of Tülü calves.
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