细化搜索
结果 21-30 的 477
Rice Blast, A Major Threat to the Rice Production and its Various Management Techniques
2022
Kapil Simkhada | Rabin Thapa
Rice (Oryza sativa L.) is the most important staple cereal crop which is consumed by more than 50% of world population. It contributes 23% and 50% of total calories consumed by world and Nepalese population respectively. Among various abiotic factors affecting rice, rice blast is the most disastrous, causing 70-80% yield loss. This disease was originated in China around 7000 years ago. In Nepal, it was first reported in Thimi, Bhaktapur in 1966. It is caused by a filamentous ascomycete fungus Magnaporthe oryzae (Anaemorphic form- Pyricularia oryzae). It infects all the developmental stage of plant and produce symptoms on the leaf, collar, neck, panicle and even in the glumes. It decreases the rice production by an amount, enough to feed 60 million people every year. Cloudy weather, high relative humidity (93-99%), low night temperature (15- 20°C), longer duration of dew is the most favorable condition for the outbreak of disease. The most usual approaches for the management of rice blast diseases are management in nutrient fertilizer and irrigation, application of fungicides and plantation of resistant cultivars. Besides, the use of extracts of C. arabica are reported to have an inhibitory effect on the disease. Seed treatment with Trichoderma viridae @ 5ml/lit of water have also been found effective. The chemical means of controlling blast disease shall be reduced, instead eco-friendly measures like biocontrol agents, resistant varieties, plant extracts can be practiced for disease control. Different forecasting model can be used in order to predict the disease prevalence.
显示更多 [+] 显示较少 [-]Comparison of University Students' Perceived Stress Levels in terms of Body-Mass Index Categories and Gender
2022
Burcu Köksal
The main purpose of this study is to compare the perceived stress level of university students in terms of body-mass index categories and gender. 235 university students (183 female, 53 male) between the ages of 18-40 participated in the study. Participants were selected from six different departments of six universities by convenient sampling. In the study, a personal information form asking about university, department, age, disease status, drug use, weight, height and gender, and a perceived stress scale were used as data collection tools. While body mass index (BMI) categories and gender were determined as independent variables in the study, perceived stress level was determined as dependent variable and the data were analysed with a one-way ANOVA test. The findings revealed that there was no statistically significant difference in the perceived stress levels of the participants in terms of gender and body mass index categories. However, for one factor of the stress scale (readiness to cope with stress), participants in the normal body mass index range reported significantly less stress than participants in the obese body mass index range. The findings will be discussed in the light of the literature.
显示更多 [+] 显示较少 [-]Bioremediation of Heavy Metals by Use of Bacteria
2022
Orcan Demircan | Abdul Razaque Memon
Heavy metal pollution generally occurs due to socio-economic, industrial, and anthropogenic activities, which may cause an environmentally hazardous and serious severe threat to the survival of the organisms (genotoxic, carcinogenic, and clastogenic effects on it). Many physical and chemical remediation approaches have been proposed to deal with this pollution, but these are very time-consuming and costly. While bioremediation stands out as an inexpensive and efficient approach, the use of bacteria is thought to be a potential and productive organism to prevent this pollution. This review has evaluated the bacterial potential to clean up heavy metals from the environment and elucidated the mechanisms responsible for bioremediation.
显示更多 [+] 显示较少 [-]Epidemiological Risk Factors and Progression of Gastrointestinal Parasitic Infestation among Food Animals of Bangladesh: A Systematic Review and Meta-analysis
2022
Mahamudul Hasan | Md. Mukthar Mia | Tiluttom Bhattacharjee | Shamia Khan Lisa | Minhajul Islam
The gastrointestinal parasitic infestation seems to have a substantial economic impact on the entire livestock production industry. Because of the parasites' environmental appropriateness, numerous domestic animals in Bangladesh are particularly susceptible to the infestation; however, the extent to which people are aware of the potential risk factors is debatable. Therefore, the current meta-analysis' objective is to determine the precise understanding of potential risk variables and the impact of climatological variations on five important gastrointestinal parasites: Paramphistomum species, Strongyloides species, Trichuris species, Schistosoma species, and Moneizia species. Four globally recognized databases, including Web of Science, Scopus, PubMed, and Google Scholar were screened to choose the studies published in English language from 2000 to 2020. Finally, 29 studies were selected for further analysis and recorded the maximum prevalence in Paramphistomum species (26%; 95% CI: 19-33), followed by Strongyloides species (9%, 95% CI: 5-12), Trichuris species (10%, 95% CI: 4-17), Schistosoma species (19%, 95% CI: 7-31), and Moneizia species (8%, 95% CI: 5-10); besides the overall prevalence was noted as 15% (95% CI: 11-18). Furthermore, subgroup analysis revealed that parasite infestation was most prevalent in females (21%) and the elderly animal population (14%) and the summer season (26%). To sum up, the current meta-analysis visualized the epidemiological risk factors with the overall incidence of five major parasite infestations in livestock animals in Bangladesh; hence, the government and shareholders may employ it as proof before launching any control programs or improving farmers' awareness.
显示更多 [+] 显示较少 [-]The Effect of Roasting on Volatile Compounds of Ground Coffee and Turkish Coffee Brew
2022
Ceyda Dadalı
Roasting is the most important coffee processing stage that affects coffee flavour. Coffee brew is prepared by various methods and Turkish coffee brewing technique is one of the oldest methods among other coffee preparation techniques. In this study, volatile compounds of light, medium, dark roasted ground coffee and Turkish coffee brews prepared from light, medium, dark roasted coffees were evaluated and the effect of roasting process was determined. The volatile compounds from acid (2), alcohol (1), aldehyde (2), furan (8), furanone (3), ketone (1), lactone (1), phenol (3), pyrazine (19), pyridine (1), pyrrole (6), and thiophene (1) chemical group was detected in all roasted ground coffee samples. However, volatiles compounds from acid, alcohol and furanone group were not detected in any Turkish coffee brew. Pyrazines were main volatile compounds of light roasted ground coffee and Turkish coffee brew of light roasted coffee. On the other hand, furans were main volatile compounds of medium, dark roasted ground coffee and Turkish coffee brew prepared from medium, dark roasted coffees followed by pyrazines.
显示更多 [+] 显示较少 [-]Perspective Regulatory Framework on Health Claim of Tea-Mini Review
2022
M Iqbal Prawira-Atmaja | Kralawi Sita | Stefania Stefania Widya Setyaningtyas | Hilman Maulana | Doni Setiadi | Sri Priatni | Anny Sulaswatty
Tea is a popular beverage with potential health benefits for those who consume it regularly. Tea products with health claims require scientific evidence based on clinical trials with generally accepted scientific data and newly developed scientific data. Tea products have been labelled FOSHU in Japan, claiming to reduce body fat and cardiovascular risk. In The USA, health claims on tea cannot be recommended and categorized as Qualified Health Claims. In Europe, health claims for tea still required further research to provide accepted scientific data. This review aims to explain the position of tea products based on the perspective of the regulatory framework of food health claims in the different official agencies in the United States, Europe, and Japan.
显示更多 [+] 显示较少 [-]Analysis of Clade V MLO Gene Expressions in Hazelnut Leaves upon Exposure to Powdery Mildew
2022
Ulku Baykal | Kadriye Özcan
Powdery mildew affecting European hazelnut Corylus avellana L. trees in Turkey is caused by the obligate biotrophic fungus Erysiphe corylacearum. This fungal disease causes significant economic losses by reducing the yield and quality of hazelnuts. Loss-of-function mutations in the mildew resistance locus o (MLO) gene family of many plants confer high levels of broad-spectrum resistance to powdery mildew. The proteins encoded by the genes at the MLO locus are divided into approximately seven different conserved clades. Among them, the phylogenetic clade V has been shown to be involved in PM susceptibility, as inactivation of these genes leads to long-term disease resistance in dicotyledons. In this study, we examined the temporal expression pattern of three hazelnut MLO genes, previously identified as clade V, in response to powdery mildew infection in C. avellana cv. Tombul. Leaves are the main tissue affected by the powdery mildew pathogen in hazelnut plants. Analysis of MLO expression in hazelnut leaves showed that CavMLO2 and CavMLO6 were significantly upregulated after challenge with E. corylacearum, providing preliminary evidence that they may be involved in PM susceptibility. Thus, these results present a basis for the isolation and use of relevant genes in plant breeding for disease resistance. Moreover, expression profiles of the clade V MLO genes are also important to identify candidate genes that need to be silenced or edited for future molecular studies to obtain resistant hazelnut varieties.
显示更多 [+] 显示较少 [-]Evaluation of Environmental Barium Concentration Biomonitoring in Tree Rings
2022
Kaan Işınkaralar
The effect of barium element that can be extremely harmful heavy metal to human and environmental health in urban centers. The barium can cause various environmental pollution due to its anthropogenic accumulation in the environment. Also, it has negative effects on plants, animals, and humans through atmospheric deposition. All Barium (Ba) compounds are harmful heavy metals and they show a poisonous effect on the environment. Thus, it is crucial to determine the Ba concentration in plants grown in areas with high pollution in the landscape, park, and roadside. Biomonitoring with the tree species can be determined which is the best passive biomonitoring method with the tree rings formed by the effect of seasonal differences. The barium has been accumulated in the tree rings for a long time that can provide critical knowledge about the atmospheric barium deposition. The temporal and spatial variations of Ba concentration were analyzed with organs of Ailanthus altissima (Mill.) as biomonitors. This study results show that the outer bark of Ailanthus altissima (Mill.) is a convenient biomonitor for Ba deposition.
显示更多 [+] 显示较少 [-]The Effect of Different Salinity Levels on Germination Development of Some Flax (Linum usitatissimum L.) Varieties
2022
Mehmet Zeki Koçak | Merve Göre | Orhan Kurt
Salinity, which is one of the abiotic stress factors, severely restricts plant production as a result of the negative effects of plants in different growth and development periods. Therefore, it is extremely important to determine the tolerance limits of plants to salinity in order to eliminate the limiting effect in terms of plant growth. Flax is an industrial plant that is used for multiple purposes and has commercial importance in the world. This research was carried out in controlled laboratory conditions in 2021 to determine the effects of salinity on the germination of flax seeds.In the study, germination rate, root length, root fresh weight, shoot length and shoot fresh weight were evaluated. The result showed that significant differences between different NaCl solutions for all evaluated characters. Although the highest value was obtained in the control group in Mures variety, the highest value was obtained in 25 nM NaCl concentration in all other characters except for the germination rate in Dakota variety. The highest germination rate of 93.3% was obtained from the control application (0 mM NaCl) in both varieties. On the other hand, there was no germination in both varieties in 200 mM application.
显示更多 [+] 显示较少 [-]Mitigation of Chilling Stress Effects on Eggplant Seedlings by Exogenous Application of Melatonin
2022
Gökçen Yakuboğlu | Şebnem Köklü Ardıç | Yakup Cuci | Ahmet Korkmaz
The purpose of this study was to explore the possibilities of improving chilling stress tolerance of eggplant seedlings through exogenous melatonin (MEL) application. Eggplant (Hadrian F1) seedlings were treated with various concentrations (0, 1, 5 or 25 μM) of MEL via soil drench after which they were subjected to chilling stress at 5°C/10°C (night/day) for 3 days. Following stress imposition, the efficacy of MEL applications on enhancing chilling stress tolerance was determined by several physical and physiological measurements and biochemical analyses. The results demonstrated that exogenous application of MEL alleviated the adverse effects of chilling stress in eggplant seedlings. Among the MEL concentrations tested, 5 µM was determined as the most effective concentration since antioxidant enzyme (CAT, POX and APOX) and photosynthetic activities increased while visual and membrane damage decreased in 5 µM MEL-treated seedlings. Also, these results are the first experimental evidence that exogenous application of MEL could improve chilling stress tolerance in eggplant, but further detailed studies are necessary to better understand the mechanism in acquiring chilling tolerance.
显示更多 [+] 显示较少 [-]