Vol. 4 No. 3 (2021): Vietnam Journal of Agricultural Sciences

This study aimed to diagnose swine dysentery (SD) caused by Brachyspira hyodysenteriae in pigs by the PCR method in Vietnam. Of the 250 samples, 29 isolates of B. hyodysenteriae (11.60%) were identified by PCR in seven provinces of Northern Vietnam, and the infection rate differed from region to region. From the positive cases of B. hyodysenteriae, we analyzed B. hyodysenteriae infected cases according to the ages of the pigs, farm sizes, and veterinary hygiene practices to get more information about the disease in Vietnam. The results showed that the positive B. hyodysenteriae samples were commonly seen in post-weaning pigs (32.14%) in households (20.73%) with poor hygiene (24.69%). Clinical signs of SD included high fever (100%); anorexia (100%); watery, bloody diarrhea, usually gray to brown in color (100%); and weight loss (86.42%). Gross lesions of SD were limited to the large intestine were described as having a fibrinous, blood-flecked membrane covering the mucosa (93.75%), swollen with hemorrhaged colon and cecum (75.00%), and mesenteric lymph nodes (81.25%).

The objective of this research was to quantify the effects of water-saving regimes and fertilizer application improvement on water productivity, N-use efficiency, and rice yield. The results showed that the tested water treatments did not have significant effects on the growth and development, yield components, and final grain yield, but water productivity was significantly increased from 1.28 kg grain m-3 (W0) water to 1.74 kg grain m-3 water (W1) and 1.94 kg grain m-3 water (W2). In addition, the percentage of total irrigation water saved from W1 and W2 were 25.24-44.52% compared to continuous flooding. Fertilizer deep placement (FDP) combined with organic compost significantly increased the grain yield of the tested hybrid rice variety. Average grain yield increased quickly from 2847 kg ha-1 with 0 kg N ha-1 to 5263 kg ha-1 with 120 kg N ha-1 under the fertilizer deep placement method. The highest total nitrogen uptake, agronomic nitrogen efficiency (ANE), and nitrogen uptake efficiency (NUE) were obtained from alternate wetting and drying at a -20cm water depth and the fertilizer deep placement method (W1N2). In addition, it also gave the highest income in comparison with the other treatments. Therefore, alternate wetting and drying at a -20cm water depth and fertilizer deep placement method should be encouraged for implementation in other regions of Vietnam.

The genus Dialium belongs to the Caesalpinioideae family, consisting of approximately 30 species distributed in the tropical regions. Secondary metabolites from the  Dialium genus have been reported to exhibit various biological activities including antioxidant, cytotoxicity and antimicrobial activities. This work describes the isolation and characterization of five compounds from the leaves of Dialium cochinchinense Pierre. Their structures were established by spectroscopic analysis, including MS and NMR spectra. Accordingly, the isolated compounds were identified to be lupeone (1), b-sitostenone (2), β-sitosterol (3), daucosterol (4), and dihydrokaempferide (5). To the best of our knowledge, this is the first report of the isolation of compounds 1 and 5 from the genus Dialium.

Overwhelming scientific evidence shows agriculture is heavily impacted by negative climate change effects. While agriculture is affected, the sector is also the second-largest contributor to climate change, creating challenges in adaptation and mitigation strategies. Climate-smart agriculture (CSA) is a holistic approach to managing landscapes, utilized to guide farmers in the context of a changing climate. CSA is an attractive option for Vietnam, an agricultural country extremely vulnerable to the impacts of climate change. Farmers and communities in Vietnam are facing significant risks. Changes in farming conditions, climate, and productivity threaten agriculture and livelihoods. The aim of the current study was to assess the effects of climate change on the people and agricultural systems in Thuong Bang La (TBL) commune, Vietnam, utilizing climate-smart agriculture rapid appraisal (CSA-RA) tools. The results indicated that agricultural production has been negatively impacted, with erratic and varied weather patterns causing outbreaks of disease, and reductions in the yield and productivity of livestock and cropping systems. Disasters including flooding, storms, and droughts are a prominent threat, leaving farmers unsure of how to cope. Through a showcase of CSA technologies, farmers were able to highlight their preferences for practices including mulching, drip irrigation and conservation agriculture in orange groves, bio-fertilizers and integrated pest management (IPM) in rice production, and using biological bedding in chicken raising. The study showed immediate openings to initiate context-specific CSA interventions and building the resilience of the agricultural systems in the development of one of the first climate-smart communes in Vietnam.

The rhizosphere microorganisms can form beneficial, pathogenic, or neutral relationships. These relationships can promote plant growth and productivity. Among them, a number of Variovorax isolates from the rhizosphere were isolated. Bacteria Variovorax strain C6d (AB552893) was isolated from the non axenic culture of Chlorella spp., C6. The cell was Gram-negative, motile, non-spore-forming, short and rod-shaped (0.5-1.0x1.5-2.0µm). Colonies were in white colour after 7 days on 10-fold diluted Nutrient Broth. The strain was able to tolerate NaCL to 1.0% but not to 4.0% of NaCl. It grew quite well at temperatures ranging from 10°C to 37°C, yet did not show any growth at 4°C and 42°C. The dominant isoprenoid quinone was ubiquinone 8 (Q8). The major fatty acid composition of this strain was summed feature 3, 16:0 and 18:1:w7. The DNA G+C content of strain C6d was 70.4 mol%.

This study aimed to determine the perceptions of climate change of undergraduate students at Vietnam National University of Agriculture (VNUA). The study employed quantitative and descriptive methods using a five-point Likert scale instrument. The respondents were composed of 276 undergraduate students from three faculties, viz. the Faculty of Environmental Sciences (FES), the Faculty of Agronomy (FA), and the Faculty of Economics and Rural Development (FERD). The results showed that students were generally well aware of the causes of climate change, the effects of climate change, and actions to mitigate climate change (average value > 3.5). However, students were mostly well aware of the causes and impacts that are common and direct. Students did not have a good understanding of the causes related to food production and consumption. Students also did not know how climate change can affect social issues such as conflict and war issues, or inequality in income and gender. Among the three faculties, students of the FES had a better awareness of the causes and impacts of climate change but were less aware of the actions to mitigate climate change. Internet and television/radio were the main sources of information about climate change for students (88% and 61%, respectively). This study showed that it is necessary to increase the provision of information related to climate change through the media as well as to integrate climate change knowledge into training programs at all levels from high school to university to improve the students' perceptions of climate change.

Southern rice black-streaked dwarf virus (SRBSDV) causes severe epidemical disease on rice with the infected area up to millions of hectares in South China and North and Central of Vietnam. So far, there are no effective, cheap, quick, and practicable methods for diagnosing SRBSDV. The conventional RT-PCR technique is the most popular method for detecting SRBSDV with high accuracy. However, it is hard to apply this method for large-scale SDBSDV diagnosis because of the requirements of expensive reagents and instruments, as well as complex procedures. Meanwhile, SRBSDV diagnostic techniques based on antigen detection have outstanding advantages due to their low cost, easy manipulation, and wide application possibility. Today, there are still no commercially available specific antibodies to SRBSDV. In a previous study, to develop the SRBSDV diagnostic technique by the ELISA technique, a SRBSDV specific antibody was generated by a recombinant P10 envelope protein (66kDa), which has a titer of 1:5,000. In this study, we continued to study the production of SRBSDV specific polyclonal antibodies from small antigen–rich peptides from the SRBSDV P10 envelope protein. The resulting purified antibody can specifically bind to the P10 protein and at the diluted concentration of 1:100,000 it can detect SRBSDV in infected rice samples via the dot-blot technique. Our research results open up new opportunities for proactive antibodies to develop a SRBSDV membrane rapid diagnostic kit.

This study focused on presenting the views of members of a professional accounting group about intangible assets accounting in Vietnam. This group consisted of 44 random  interviewees who were auditors, lecturers, and banking staff, among others. Based on the results of this survey, the characteristics of the professional accounting group, including occupation, educational level, and work experience, etc., were collected. The accounting regulations for intangible assets in Vietnam in accordance with the guidelines of Vietnamese Accounting Standard (VAS) No. 04 (Intangible assets and other circulars) were then analyzed. Especially, these interviewees indicated three main obstacles of intangible assets accounting through this survey. First, the skills and knowledge of accounting staff are the most current weaknesses of intangible assets accounting. Following that, the slow integration of Vietnamese accounting regulations with the international accounting system for intangible assets is a difficult point. Lastly, the limited knowledge of managers and internal governance are weak points. Hence, to improve intangible assets accounting in Vietnam, the Ministry of Finance (MOF) should organize additional training courses or workshops to train accountants and managers based on the contents of International Accounting Standard (IAS) No. 38 for intangible assets and IAS 36 for the impairment of assets. In addition, small specialized discussions among accountants, lecturers, auditors, and others in one city should be encouraged to open accounting seminars/workshops. These gatherings would be a good way to share their accounting experience with each other and improve their knowledge of accounting. 

Since the end of 2019, 92.1% of rural households in Hai Phong city had been able to access and use clean drinking water, which meets national standards as a result of developing a clean water supply system consisting of 205 plants with various management models. The authors applied the desk-study method to collect and review literature research, select a group of six criteria, and then applied the criteria to assess the system's sustainability based on Likert's 3-point scale. The results show that criteria scores ranged from 1.9 points to 2.5 points, while the total score of the whole system is 12.9 points - reaching an average sustainability level. The authors propose that in order to improve the sustainability of the clean water supply system in the rural areas of ​​Hai Phong city in the future, management agencies and investors need to apply a solution of propagating rural people to increase their usage volume of clean water, which will help to increase the actual operating capacities of the plants, thereby increasing the revenue and profits of plant investors.