Vietnam Journal of Agricultural Sciences
Tạp chí của Học viện Nông nghiệp Việt Nam
Sustainability Assessment of the Rural Clean Water Supply System in Hai Phong City
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.
ECONOMICS, SOCIETY AND RURAL DEVELOPMENT
Intangible Assets Accounting in Vietnam: Perspectives of a Professional Accounting Group
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.
Generation of Synthetic Peptide-Specific Antibody for the Development of A Southern Rice Black-Streaked Dwarf Virus Diagnostic Test
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.
Characterization of Variovorax Strain C6d Isolated from the Algae-bacteria Consortia
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%.
Assessing Climate Change Impacts and Prioritizing Adaptation Measures Using Climate-Smart Agriculture Rapid Appraisal (CSA-RA): A Case Study in Thuong Bang La Commune, Van Chan District, Yen Bai Province
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.
Detection of Swine Dysentery (SD) caused by Brachyspira hyodysenteriae via PCR in Northern Vietnam
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%).
ANIMAL SCIENCE – VETERINARY MEDICINE – AQUACULTURE
Students’ Perceptions of Climate Change: A Case Study at Vietnam National University of Agriculture
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.
Chemical constituents of leaves Dialium cochinchinense Pierre
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.
Water-Saving Irrigation and Nitrogen Fertilizer Use Efficiency for Irrigated Rice in the Red River Delta, Vietnam
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 Impacts of Climate Change on Agricultural Production and Sustainable Agriculture of Smallholder Farmers in Vietnam
Climate change is one of the greatest threats to human beings, and agriculture is one of the fields that is most negatively affected by climate change. Farmers around the world and global food supply chains are impacted by the more extreme weather phenomena and increased damage of diseases and pests caused by climate change. Today, almost all agricultural enterprises and farms consider climate change a serious long-term risk for their production. Agricultural land systems can produce significant greenhouse gases (GHGs) by the conversion of forests to crop- and animal lands, and also through the weak management of crops and livestock. Around the world, cultivation and cattle production accounts for 25% of global GHG emissions (Javeline, ‎2014). However, under suitable conditions, agriculture can create environmental conditions that can help minimize pollution and the negative effects of climate change including carbon absorption by green plants in forests, and fields for watershed protection and biodiversity conservation. Sustainable agriculture helps farmers to adapt, maintain, and improve productivity without applying harmful techniques. In turn, this allows farms to manage and mitigate climate-related risks in their supply chains. The Sustainable Agriculture Network (SAN) has found new ways to incorporate smart climate cultivation methods into all farming practices to help farms and enterprises carry out agriculture sustainably.
Protection of Geographical Indications in Vietnam: towards Raising the Participation of Producers
This paper aims to review the current situation of the Vietnamese geographical indication (GI) system from both the legal and practical perspectives. It examines how the top-down approach influences the effectiveness and sustainability of the whole system. Further, the paper refers to the European Union (EU)’s experiences, particularly those of France - a representative of the bottom-up approach - to examine whether a shift to the producer-driven approach in GIs is workable in Vietnam. The paper argues that more active roles should be vested on producers represented by their associations during the course of establishment and management of GIs. Taking into account the capacity of producers and their associations in this current stage, the paper suggests a transition period before the producers assume the leading role in the whole system. During that period, it is recommended to endorse the producers’ role through legal recognition of the producers’ representative organizations, capacity building, and awareness-raising for producers and their associations to achieve desirable outcomes for GI development.
Effects of Culture Conditions on the Antibacterial Activity of Streptomyces Spp. against Erwinia Spp. Causing Soft Rot Disease on Asparagus Officinalis
Erwinia is a genus of Enterobacteriacea containing mostly pathogens, which cause soft rot disease in many ornamental plants and crops, including Asparagus officinalis. Chemical treatments to control Erwinia have lost their attractiveness because of the development of resistant strains and the negative impacts on the environment and human health. Therefore, the study of biological controls of soft rot disease has gained great importance. There are several types of microorganisms that show activity against Erwinia spp. such as Pseudomonas fluorescence, Bacillus subtilis, and Streptomyces spp. Among them, Streptomyces spp. are found to be the most effective control agents. In this study, 64 isolates of Streptomyces were screened for their antibacterial activity against Erwinia spp. The results indicated that 18 isolates showed an antagonistic reaction against Erwinia spp. Among them, isolate D5.1 showed the highest inhibition activity. In addition, the morphological and antibacterial activities of isolate D5.1 grown in different conditions were also characterized.
Studying the Biological Characteristics of the Stingless Bee Tetrigonilla Collina Smith 1857 (Apidae: Melipona) in Hanoi, Vietnam
Stingless bees are distributed in tropical and subtropical regions. There are over 16,000 species of stingless bees around the world, among which, 42 species are from Asia (Kerr & Maule, 1964). Sixteen species of stingless bees have been identified in Vietnam (Sakagami, 1975; Sakagami, 1978; Engel, 2000; Chinh et al., 2005; Rasmussen, 2008). In this study, the biological characteristics of Tetrigonilla collina, as a representative for Southeast Asian stingless bees, were observed and recorded. The worker cell dimensions were 5.30 ± 0.34mm in length by 4.28 ± 0.37mm in width with a volume of 45.02 ± 5.74mL (food volume: 19.05 ± 3.5mL; ratio: 42.27%). The new cells were mostly built in the morning (from 2:00 to 10:00 am) and the queen laid eggs (2.52 ± 0.81 sec per egg) and capped the cells in the afternoon (from 12:00 to 17:00 pm). The average worker-cell building period was 12.03 ± 3.78 hours. Mainly, six of first ten bees that inserted made food discharges in a cell. The food discharge occurred in a very short time, which was 1.58 ± 0.6 minutes. The new cell numbers of the colony were reduced at the end of the experimental period.
Effects of Furrow Height and Amount of Manure Compost on the Growth, Yield, and Quality of Organically Grown Green Asparagus
A two-season field trial was carried out in the Upland Crop Experiment Field of the Faculty of Agronomy, Vietnam National University of Agriculture (VNUA) to assess the effects of three furrow heights (20, 35, and 50cm) and three manure compost levels (15, 25, and 35 tons ha-1) on the growth, yield, and quality of green asparagus (Asparagus officinalis L.) grown organically. The experiments were arranged in a randomized completely block design (RCBD) with three replications. The results showed that the harvested yield was highest (11.3 and 25.1 quintals ha-1 in the 2019 autumn and 2020 spring season, respectively) in the treatment with a furrow height of 35cm and compost level of 35 tons ha-1 in both seasons, and explained by the increased spear diameters and number of spears per plant in this treatment when the furrow height and compost level were increased. Additionally, the chlorophyll content, water loss, and dry matter weight of the spears also increased when the furrow height and compost level increased. The obtained quality of the spears under organic management at the furrow height of 35 cm and compost level of 35 tons ha-1 was higher than the other treatments with higher reducing sugars, vitamin C, and Brix values, while the residue nitrate contents of all the treatments were lower than the allowed safety threshold.
Effects of Salinity Stress on the Growth, Physiology, and Yield of Soybean (Glycine max (L.) Merrill)
This study was conducted to evaluate the salt tolerance ability of two soybean cultivars under salinity conditions using a selection of growth and physiological parameters. Three weeks after germination, plants began being treated with either a 100 mM concentration of NaCl in Hoagland solution or a non-salinity (0 mM NaCl) solution. The results showed that the plant height, number of leaves, leaf area index, and shoot and root biomasses were significantly reduced under salt conditions. A similar tendency was observed in several physiological parameters (SPAD, Fv/Fm). Since all the salt-treated plants of the D8 cultivar were dead after 40 days under the 100 mM NaCl treatment, the yield of D8 could not be obtained, while the treated plants of the D140 cultivar experienced a marked decrease in yield compared to the control plants. In this study, we identified that the D140 soybean cultivar had a better salt tolerance than the D8 soybean cultivar at a 100 mM NaCl concentration.
Study on Stem Cutting Propagation of Gynostemma Pentaphyllum (Thunb.) Makino in Hoa Binh Province
Gynostemma pentaphyllum (Thunb.) Makino is a medicinal plant distributed mostly in the mountainous areas of Vietnam. G. pentaphyllum contains more than 189 types of saponin which can be used for the treatment of various diseases. Currently, due to over-exploitation, this plant species is under threaten. Our research aimed to study a suitable method for plant propagation by stem cutting techniques to promote the growth and development of G. pentaphyllum. Six experiments were conducted to (i) evaluate the established seedling rates of different G. pentaphyllum varieties, and choose the best variety to (ii) evaluate the established seedling rate influenced by different factors, viz. stem cutting position, cutting season, growing in the selected substrates, stem cutting length, number of buds per stem, and application of α-NAA. The results showed that among five varieties, G2 which was collected in Mai Chau district disclosed the highest ability to shooting, the highest number of roots per stem cutting, the shortest nursery days, the highest shooting rate, and the highestestablished seedling rate. We also determined that using middle-aged plants for stem cuttings, at 15-20cm in length, with 2 nodes and grown in Spring and Winter cropping seasons, using growing substrates with a mixture of 50% of black sand and 50% of soil, and plus α-NAA 50ppm in 3-5min produced the highest explant rate. The established seedlingsat the time of explant were 15-20cm in height, containing 4-5 leaves and at least 9-10 roots per cutting, and were 30-32 days.
Effects of Cover Methods and Nitrogen Levels on the Growth and Yield of Tomato
To study the effects of cover methods and nitrogen (N) levels on the growth and yield components of tomato Cv. Pear F1, field experiments with a 4x3 factorial design were conducted in the 2019 spring and winter seasons using a randomized complete block design with three replications. The cover methods included four treatments: bare soil (BS), black plastic mulch (BPM), transparent polypropylene row cover (RC), and a combination of BPM and RC (BPMRC) with the RC removed approximately 30 days after transplanting. Nitrogen (N) was applied at three levels (150, 180, and 210 kg N ha-1). Using BPM and RC generally led to an increased air temperature, air humidity, soil moisture, and soil temperature compared to the BS treatment. Higher N rates (180 and 210 kg N ha-1) did not result in different tomato fruit sizes and fruit weights but positively increased fruit yield and quality (Brix values and fruit dry weight) as compared to the 150 kg N ha-1 addition. The cover methods positively affected the yield components and fruit yield of tomato as well as the fruit characteristics compared to the BS treatment. Using cover materials (BPM and RC) combined with a higher N application significantly increased the yield attributes and fruit yield. The highest fruit yield was achieved under the mulching treatment by black plastic (BPM treatment) combined with a 210 kg N ha-1 application, resulting in 50.90 tons ha-1 in the spring and 58.27 tons ha-1 in the winter.
Effects of Baby Corn Density on the Crop and Weed Performance under Different Maize-Soybean Intercropping Systems
This study was conducted to examine the effects of baby corn density on the crop and weed performance under two different maize-soybean intercropping systems. Treatments included four baby corn densities (D1= 138,888 plants ha-1, D2 = 111,111 plants ha-1, D3 = 92,592 plants ha-1, and D4 = 79,365 plants ha-1), and three intercropping methods (P0 = a sole cropping of baby corn, P1 = 1 row of soybean + 1 row of baby corn (density of soybean, 10 plant m-2), and P2 = 2 rows of soybean + 1 row of baby corn (density of soybean, 20 plants m-2)). Physiological characteristics and yield were measured for the baby corn and soybean. The weed species, weed frequency, and the growth of the weeds were recorded at the final harvesting time of the baby corn. The results showed that the yield of soybean and the growth of the weeds were statistically different under the different maize-soybean intercropping systems. Increasing the baby corn density increased the leaf area index, dry matter accumulation, and cob yield, but did not have a clear effect on the soybean yield under both intercropping methods. In addition, the P2 intercropping method produced significantly higher soybean yield and gave better results of weed growth reduction in comparison with the P1 intercropping method. In the P2 intercropping method, baby corn should be grown at a density of 111,111 plants ha-1 to optimize the population productivity and achieve reasonable weed control for the sustainability of agriculture.
Effects of Mineral Fertilizer Doses and Ratios on Tea Yield and Quality
Mineral nutrients are essential to plant growth and development. The present study aimed to evaluate the effects of mineral fertilizer doses and N:P:K ratio on growth, yield, and raw material quality of the tea variety PH10 to improve the production of high-quality tea products. The field experiment was conducted from 2015 to 2017. A two-factor experiment was designed by split-plot design with three replications. The mainplot treatments were three fertilizer doses of N for one metric ton of fresh shoot products (30, 40, and 50 kg N ha-1). The subplot treatments were two NPK ratios (3:1:1 and 3:1:2). Plant height, leaf canopy, plant diameter, shoot yield parameters, shoot components, biochemical compounds, and sensory quality for Oolong and Sencha tea products were evaluated. The results showed that increasing fertilizer doses from 30 up to 40 kg N per ton of fresh product improved remarkably growth, yield, and tea quality of PH10 variety. Different fertilizer ratios resulted in variations in plant growth, the content of carbohydrate, sensory quality for taste and flavor as well as total sensory quality with higher values at NPK ratio of 3:1:2. Applying mineral fertilizer with an NPK ratio of 3:1:2 and 40kg N per ton of fresh shoot products was recommended to bring about the most benefits of tea yield and quality as well as economic profit.
An Overview of Drug Effects on Bone Healing on Animal Research Models
Bone fracture is a common health problem in humans and animals, and the healing of the bone fracture is a complicated process. Several drugs may be used concurrently with the treatment of fractures, but they may interfere with the healing process of the bone. The present research reviewed previously published studies with the objective to enhance the understandings of the effects of different drugs on bone healing. There is clear evidence that antibiotics, corticosteroids, non-steroidal inflammatory drugs, and chemotherapeutic drugs all affect bone healing. By contrast, the effect of anticoagulants on bone healing is controversial, so more research is needed to determine its efficacy. In addition, there is no direct evidence to approve the effect of anesthetics on bone healing, so this is another area in need of further research.
The First Record of Adult Spotted Sea Bass (Lateolabrax maculatus, McClelland, 1844) from the Coastal Waters of Quang Ninh Province, Vietnam
Spotted sea bass (Lateolabrax maculatus, McClelland, 1844) is a species belonging to the genus Lateolabrax (Lateolabracidae), and is characterized by the many distinct black spots on the bodies of mature fish. For the first time, six specimens have been recorded in Quang Ninh province. The specimens were collected from Luon Cave in Bai Tu Long National Park in May-June 2019. The new specimens collected from Quang Ninh, Vietnam are different from the recorded specimens from Japan, Korea, Taiwan, and China in terms of lateral line scales (LLS) as the samples collected in Quang Ninh, Vietnam have 94-97 scales and the samples collected from the other countries have 66-82 scales. Phylogenetic analysis of the 16S rDNA sequence confirmed that all of the samples collected in Quang Ninh, Vietnam belonged to the species of spotted sea bass.
Integrated Agriculture-aquaculture Farming Systems in Vietnam: The Status Quo and Future Perspectives
The integrated agriculture-aquaculture (IAA) farming system has been considered a form of diversified agriculture applied in Asia. In this paper, several IAA farming systems practiced in Vietnam are described, and their impacts are also reviewed. It is speculated that in developing countries like Vietnam, the IAA farming system should be targeted for support as a sustainable food safety model and a form of ecosystem-based technology to reduce environmental impacts, adapt to climate change, help avoid risks from market fluctuation, and increase incomes in comparison with monoculture farming.
Swine Production and Challenges in Vietnam after African Swine Fever: A Case Study in Peri-Urban Hanoi, Vietnam
The goal of this paper was to identify major challenges in rebuilding the swine industry in Vietnam, using the Chuong My district, Hanoi as a case study. Primary data was gathered in 2020 mainly through a survey of 97 swine producers in the district. Analysis tools were descriptive and comparative statistics. Results show that after the ASF outbreak, the recovery of the swine industry in Vietnam faced several challenges, including the issues of piglet quantity and quality, changing consumer preferences which were worsened by the current Covid-19 pandemic, relatively cost disadvantage of domestic production under the context of new free trade agreements, disease risk (ASF under the condition of no effective and safe vaccine), insufficient resources of farms to restock, and environmental issues caused by swine production in rural areas. The paper proposed several recommendations to rebuilding the swine herd in order to address the issues and overcome the challenges, mainly focus on improving sow quality, market information and linkages, good practices in production, training for labor, and address environmental issues.
Investigating the Potential of Vietnamese Tea Seed Oil (Camellia sinensis O.Kuntze) for the Enhancement of Oxidative Stability in Vegetable Oils
This study examined the effectiveness of different antioxidative compounds, namely 0.2% BHA (Butylated hydroxyanisole) + BHT (butylated hydroxytoluene), 0.03% α – tocopherol, and 3% and 6% tea seed oil (TSO) on the oxidative stability of vegetable oils. Four commonly used oils, viz. rapeseed oil (RSO), peanut oil (PNO), sunflower oil (SFO), and soybean oil (SBO), were assessed by the Schall Oven test method and monitored during the 12-day preservation period under 60°C. The total oxidation values (TOTOX) of the samples treated with 6% TSO were lower than those treated with 0.2% BHA+BHT. The results indicated the potential of TSO as a novel natural antioxidant for dietary vegetable oils. Our study also suggested that TSO could serve as an effective substitution for currently used synthetic antioxidants such as BHA and BHT.
Effect of Waterlogging Duration on Germination, Physiological Characteristics, and Yield of Mungbean (Vigna radiata L.)
The study was conducted to evaluate the germination, physiological responses, yield-related traits, and seed yield of three mungbean varieties, viz. DXVN7, DXVN5, and DX11, under waterlogging coditions in the 2019 Summer. In experiment 1, the seeds of the three mungbean varieties were immersed in distilled water in Petri dishes for 12, 24, 36, 48, and 72h. Afterwards, water was removed and the percentage of germinated seeds was calculated at 84h after sowing. In experiment 2, plants were waterlogged at the seedling stage (25 days after germination) for 3, 6, and 9 days. Waterlogging depth was maintained at 3cm above the soil surface. Physiological traits were determined at the recovery period after termination of waterlogging (45 days after germination). The results showed that waterlogging significantly decreased germination percentages, plant height, root dry weight, leaf relative water content (RWC), SPAD value, Fv/Fm index, leaf photosynthesis, total dry weight, and seed yield of all varieties. Germination percentages at 12 and 24h of waterlogging were not significantly affected, whereas germination was significantly reduced at up to 36h of waterlogging. Seventy-two hours of waterlogging caused failure in germination. Nine days of waterlogging at the seedling stage adversely affected the physiological traits and seed yield of the mungbean varieties with 31% of yield reduction. Meanwhile, plants grew better at 3 days of waterlogging. Among the three varieties, DXVN7 showed the best adaptability under waterlogging conditions, attaining the highest seed germination and yield.
Production Characteristics and Strategies for Adapting to the Impact of Climate Change on Cassava Whiteflies and Viruses in Tanzania
Cassava is Africa’s most important food security crop and sustains about 700 million people globally. Survey interviews of 320 farmers in three regions of Tanzania to identify their production characteristics, and interviews with 20 international whitefly/virus experts were conductedto identify adaptation strategies to lessen the impacts of cassava whiteflies and viruses due to climate change in Tanzania. Structured and pre-tested interview schedules were conducted using a multistage sampling technique. Most of the farmers (66.8%) produced cassava primarily for food, and relied mainly on their friends (43.8%) and their farms (41.9%) for cassava planting materials. Farmers significantly differed in their socio-economic and production characteristics except for gender and access to extension support (P < 0.01). A significant association was found between extension support, sources of planting materials, and reasons for growing cassava with both the control of cassava viruses and the control of whiteflies by the farmers. A significantly higher number of farmers controlled cassava viruses (38.1%) than cassava whiteflies (19.7%). The adaptation strategies most recommended by experts were: integrating pest and disease management programs, phytosanitation, and applying novel vector management techniques.The experts also recommended capacity building through the training of stakeholders, establishing monitoring networks to get updates on cassava pests and disease statuses, incorporating pest and disease adaptation planning into the general agricultural management plans, and developing climate change-pest/disease models for accessing the local and national level impacts that can facilitate more specific adaptation planning in order to enhance the farmers’ adaptive capacities.
Effect of Temperature on Life History of Bemisia Tabaci (Gennadius) (Homoptera: Aleyrodidae) on Cassava Manihot Esculenta Crantz
The aim of the present study was to evaluate the relationships between environmental temperatures and life-history traits of whitefly Bemisia tabaci on cassava in the Northern part of Vietnam. The influence of temperature on the biological characteristics of whitefly B. tabaci fed on cassava was evaluated at 20ºC, 25ºC, 27.5ºC, and 30ºC using individual insect rearing methodology. Results of the study showed that the development time from egg to adult of B. tabaci was influenced by temperatures. The data indicated that under different temperatures (20ºC, 25ºC, 27.5ºC, and 30ºC), the life cycle of B. tabaci were 41.46, 28.64, 24.29, and 20.25 days, respectively. The determination of lower developmental threshold and degree days for whitefly development were 11.2ºC and 344.8 degree-days. There were 14.31 whitefly generations within 1 year on cassava suggesting this plant is a suitable host plant for the development and reproduction of B. tabaci. Female longevity ranged from 4.92 to 10.23 days. The fecundity ranged from 49.3 to 74.0 eggs/female. The mortality rate reached its highest rate of 36.27% at 30ºC. Our results suggested that B. tabaci had high reproduction rates and demonstrated their positive fitness traits on cassava in a wide range of temperatures, being a potential important pest of cassava cultivars.
Effects of Nitrogen Application on the Growth and Yield of Quinoa under Saline Conditions in Northern Vietnam
This study aimed to determine the optimum nitrogen application rate for quinoa in saline soils. Two experiments were conducted: (i) the first experiment was under artificial saline conditions with the two factors of saline regime (stressed and non-stressed) and nitrogen application level (0, 30, 60, 90 and 150 kg N ha-1) in net-houses located in Gia Lam, Hanoi; and (ii) the second experiment was under natural field saline conditions with the two factors of quinoa cultivar (Atlas and Moradas) and nitrogen application level (0, 30, 60, 90, and 150 kg N ha-1) in the coastal areas of Hai Hau, Nam Dinh province. Data were collected for growth duration, insect and disease infestations during the growth period, and various growth parameters and yield components at harvest. The results showed that saline stress reduced the growth and yield parameters, but did not affect the quinoa growth duration of the investigated quinoa cultivars. In both experiments, the growth parameters and yield components increased according to the increase of the nitrogen application rates from 0 to 90 kg N ha-1, then decreased when the nitrogen rates were higher. The results suggested that 90 kg N ha-1 was the optimum nitrogen application dose for quinoa growth and development under saline soil conditions.
Theoretical and Practical Issues of Research on the Consumption Needs for Safe Foods in Vietnam Using the Willingness to Pay Model
Research on consumer needs for safe foods under the willingness to pay (WTP) approach based on consumer behavior has been performed widely and has contributed greatly to the development of safe foods, assisted enterprises’ decision-making processes in improving agricultural and food products, and provided orientation to policymakers in improving public health as well as in fostering sustainable economic growth. Some of the methods used for measuring WTP for safe foods, such as contingent value (CV), choice experiment (CE), and auction experiment (AE), have made significant contributions to the evaluation of consumers’ WTP for food safety. Moreover, the application of these models has helped to estimate the effects of many factors such as demography, consumer habits, continuation of food safety, individual characteristics, promotion, and product attributes, etc., on the WTP for food safety. The trend of safe food consumption in Vietnam has distinct characteristics, some of which come from national cultural identities; therefore, Vietnamese researchers may approach the empirical studies on this issue all over the world in order to find proper methods for studying consumer needs for safe foods in Vietnam.
Factors Affecting the Capacity of Accounting Software in Controlling Frauds and Errors in Small and Medium Enterprises (Smes): A Case Study of SMEs in Hanoi, Vietnam
Financial accounting information has impacted the operation of enterprises, especially SMEs. With the development of technology, digital accounting applications are playing an increasingly important role in minimizing mistakes, and ensuring the accuracy and timeliness of accounting information. Using multiple discriminant analyses, this study confirmed the significance of accounting software in reducing frauds and errors in SMEs’ businesses despite some drawbacks. It showed that the managers’ ability to access the software and the decentralization of power in accessing the accounting software were the two key factors deciding the success/failure of applying accounting software to control frauds and errors. In addition, smart applications of the accounting software positively contributed to the elimination of frauds in enterprises. Based on these results, recommendations are drawn for SMEs, such as investing more in smart applications of accounting software, as well as updating knowledge about accounting for management, in order to get more advantages from accounting software applications for their business in the long term.