Welcome to Can Tho University Journal of Science

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Can Tho University Journal of Science (CTUJS) is an international double-blind peer-reviewed journal that publishes high quality original research and review articles in multi-disciplines covering natural sciences, technology, environment, agriculture, fisheries, biotechnology, social sciences, humanities, education, economics, law, etc... Read more

Genetic variation of Nang Thom Cho Dao rice variety based on whole genome sequencing

Huynh Ky*, Van Quoc Giang, Nguyen Loc Hien, Nguyen Chau Thanh Tung, Huynh Nhu Dien, Nguyen Nhut Thanh, Vo Cong Thanh, Yeap Swee Keong
Abstract | PDF
High-performance sequences are generating increasingly comprehensive catalogs of crop genetic variation. To make optimal use of this vast collection of data for research purposes, a robust and reproducible analytical pipeline discipline is required that is capable of accurately detecting and favoring variants. The entire genome sequencing data from the rice variety Nang Thom Cho Dao was analyzed using the appropriate bioinformatic pipeline. A total of 21 million reads with 6,6 GB of data were analyzed. SNPs and indels from the Nang Thom Cho Dao genome were found to be variable when compared to the Nipponbare reference rice genome. The result showed that the novel Indel of BADH2 gene in Nang Thom Cho Dao genome. The study will contribute valuable information to the development of genetic markers for rice breeding strategies using Nang Thom Cho Dao rice varieties.

Nutritional value and factors affecting milk production and milk composition from dairy sheep: A review

Nguyen Vu Quang*
Abstract | PDF
Sheep milk contains much higher concentrations of protein, fats, minerals, and vitamins than milk from other common domestic species such as cows and goats. High nutritional value and lower allergic sensitization compared to cow milk make sheep milk an ideal source of nutrition for humans. Moreover, advantages in physicochemical characteristics also make sheep milk a very good raw material for processing, especially in cheese making. However, dairy sheep industry remains small in many regions of the world,  mostly due to restricted genetics and limited milk production. Milk yield and composition are influenced by various factors including genetic parameters, dietary nutrient composition, parity, lambing season, milking frequency, and stage of lactation. Future research on dairy sheep in different production systems especially in developing countries and new genes regulating milk production and quality need to be undertaken.

Identification of rose black spot pathogen in Sa Đéc city, Đồng Tháp province of Vietnam

Le Hung Cuong, Pham Thi Phuong Anh, Tran Quoc Tuan, Nguyen Dac Khoa - Section Editor*
Abstract | PDF
Black spot is one of the most destructive diseases of roses, causing premature defoliation, thus progressively weakening the plant and even leading to death. This study aimed at identifying the pathogen causing black spot on Rosa chinensis Jacq. cv. nhung (Hồng Nhung) and R. chinensis Jacq. var. minima (Hồng Tỉ Muội) in Sa Đéc city, Đồng Tháp province, Vietnam, using a combination of conidia morphology and pathogenicity tests including detached leaf and intact plant techniques. A total of 32 infected leaf samples with the black spot typical symptoms were collected from six rose cultivation areas. The morphological characterization of the conidia obtained from these samples was elliptical, hyaline, two-celled and had vacuole-like structures, similar to those produced by Diplocarpon. In pathogenicity test, the symptoms were observed on cv. nhung but not var. minima in the detached leaf technique while symptoms were observed on both cultivars in intact plants technique. These included black spots with perforated edges, aggregating into bigger patches. The infected leaves could yellow and defoliate at 21 days after inoculation. Compared to the previous pathogenic studies and description of diseases on roses, the fungal pathogen was identified as fungus Diplocarpon rosae.

The Application of socio-hydrological approach to study water-related hazards in Can Tho City

Le Van Thuy Tien*, Nguyen Thanh Binh
Abstract | PDF
The concept of socio-hydrology was applied in this study to explore the interaction between urban development and water-related hazards in Can Tho using both primary and secondary data. The results showed that water-related hazards tend to increase. Many drivers are identified including both social and hydrological. The trend of water level at Can Tho station (mid-stream) in the last 20 years has a positive relationship with down-stream (Dai Ngai station), and a negative relationship with up-stream (Chau Doc station). It means that sea level rise has increasingly affected the water regime in Can Tho. Heavy short duration rainfall also contributes to urban floods. Moreover, social drivers as human behaviors and uncontrolled urban development also increase the risk. Therefore, to minimize the impacts of water-related hazards it is necessary to take into account a combination of  hard measures and soft measures. Green urban development which shows potential for improving the quality of ecosystem services and provide opportunities for urban dwellers to reconnect with nature should be promoted for disaster risk reduction.

Common mistakes in pronouncing English consonant clusters: A case study of Vietnamese learners

Tran Thi Khanh Lam, Anh Thi Nguyen*
Abstract | PDF
Pronunciation plays a significant role in English teaching and learning around the world and this particular field has received much attention from several scholars. The study was conducted to investigate common mistakes made by Vietnamese university learners while pronouncing English consonant clusters. This is a quantitative study with the participation of 39 English as a Foreign Language (EFL) learners. To collect data for the study, a pronunciation test was employed. The results show that the common mistakes made by the learners varied, depending on the types of consonant clusters. Specifically, clusters containing voiceless plosives led to the highest mispronunciation. There was also a tendency to simplify the complex clusters of three-consonant by deleting the first, second consonant, or in some cases, both. Accordingly, this study suggests pedagogical implications for teachers and learners in similar contexts in Vietnam in acquiring the pronunciation of English.

Effects of guava (Psidium guajava L.) and bhumi amla (Phyllanthus amarus Chum et Thonn) extracts on haematological parameters and oxidative stress of striped catfish (Pangasianodon hypophthalmus) fingerlings exposed to high-temperature stress

Pham Ngoc Nhu, Bui Thi Bich Hang, Nguyen Thanh Phuong, Patrick Kestemont, Do Thi Thanh Huong*
Abstract | PDF
Effects of guava (Psidium guajava L.) and bhumi amla (Phyllanthus amarus Chum et Thonn) on haematology and thermal stress mitigation of striped catfish (Pangasianodon hypophthalmus) were investigated. In a 42-day trial, fish were administered 4 diets as control (without extract), 0.2% P. guajava (Pg0.2), 0.5% P. amarus (Pa0.5), and a mixture of Pg0.2 and Pa0.5 (Mix). Fish were then subjected to temperatures of 27°C, 31°C, and 35°C for another 42 days. Haematological parameters were highest at 35°C, but these parameters were not significantly different from values recorded at 31°C on day 14 post-temperature challenge. The Pg0.2 diet modified red blood cells, haematocrit, and haemoglobin (p

Reproductive Biology of Moonlight Gourami (Trichopodus microlepis) in U Minh Thuong and U Minh Ha National Parks

Nguyen Thi Ngoc Tran*, Nguyen Thi Kim Ngan, Duong Thuy Yen
Abstract | PDF
This study aimed to provide information about the reproductive biology of moonlight gourami (Trichopodus microlepsis) distributed in U Minh National Parks. Fish samples were collected monthly from January to October 2019 at two locations: U Minh Ha (UMH, Ca Mau, n=462) and U Minh Thuong (UMT, Kien Giang, n=635). Results showed that the maturation-stage ratios of females were similar between the two fish populations. Mature females (with stage IV-ovaries) and the increase in their gonadal somatic index (GIS) were found from June to October, indicating that this period is their spawning season. GSI reached the highest values in August with 8.04% in UMH and 6.44% in UMT. Female fish of the UMH population showed higher average fecundity (7,483±3,008 eggs/female) and larger egg diameter (762±55 µm) than those of UMT (6,898±2,952 eggs/female and 754±43 µm, respectively), but these differences were not significant (p>0.05).

Genetic diversity of two successive generations of selection in bighead catfish (Clarias macrocephalus) populations

Duong Thuy Yen*, Nguyen Thi Ngoc Tran
Abstract | PDF
Selective programs associated with domestication can improve fish production but also can have an impact on broodstock’s genetic diversity. In this study, the genetic diversity of original sources (G0) from wild and cultured bighead catfish populations, as well as the two successive generations (G1 and G2) subjected to selection experiments, was assessed. G0 wild adults were collected in Ca Mau conservation area and G0 cultured fish were from a hatchery in Can Tho. The G1 fish included pure crosses and crossbreeds of G0, while G2 was the offspring of the selected G1. Fin clips from 27 to 29 individuals of each fish group were randomly sampled for genetic analysis. The amplification results using six ISSR primers showed that the genetic diversity was relatively higher in G0 (effective number of alleles Ne from 1.43 to 1.49; heterozygosity He from 0.265 to 0.290) than in G1 (Ne = 1.32±0.04; He = 0.201±0.023) and G2 (Ne = 1.34±0.04; He = 0.216±0.023). Genetic differences increased between the original populations and the descending generations. To reduce the detrimental impacts of low genetic diversity in domesticated bighead catfish in the Mekong Delta, it is recommended that broodstock in later generations should be produced in a larger...

Effect of enzyme-assisted extraction on yield, composition, and antimicrobial activity of essential oils from Rosmarinus officinalis L. grown in Lam Dong Province, Viet Nam

Nguyen Van Ngoc*, Do Tran Tham Thuy, Vu Bao Ngoc, Hoang Thi Binh
Abstract | PDF
In the present study, viscozyme L pre-treatment for aerial parts of Rosmarinus officinalis L. (rosemary), grown in Lam Dong province, was performed to evaluate the effective extraction of essential oils by hydro-distillation. Enzymatic pre-treatment with 1 g viscozyme L enzyme mixed with 5 mL sodium chloride 15% at 50oC for 1 hour, followed by hydro-distillation, was seen to slightly increase the yield of rosemary essential oils from 0.96% to 1.08%. GC/MS analysis showed the presence of 32 compounds in rosemary essential oils, of which the major components were α-pinene (29.71 - 32.17%) and cineol (17.55 - 18.74%) in both the control and the enzymatically treated samples. The results also revealed that rosemary essential oils obtained from both the control and the enzymatically treated samples exhibited moderate antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans in all tested concentrations.

Structural and electronic properties of hydrogen - functionalized armchair germanene nanoribbons: A first-principles study

Nguyen Duy Khanh, Nguyen Thi Hong Hue, Nguyen Thanh Tien, Vo Van On*
Abstract | PDF
Structural and electronic properties of armchair germanene nanoribbons functionalized by hydrogen atoms (H-AGeNR) are studied through density functional theory (DFT) method. The DFT quantities for analyzing the structural and electronic properties are fully developed through the DFT calculations, including the functionalization energy, relaxed geometric parameters, orbital- and atom-decomposed energy bands, electronic density of states, charge density, and charge density difference. Under hydrogen functionalization, the functionalization energy is achieved at -2.59 eV, and the structural parameters are slightly distorted. This provides evidence of good structural stability of the functionalized system. Besides, the very strong bonds of H-Ge are created because the electrons are transfered from Ge atoms to H adatoms, which induces hole density in the functionalized system, which is regarded as p-type doping. As a result, the π bonds of 4pz orbitals at low-lying energy are fully terminated by the strong H-Ge covalent bonds, in which the strong hybridizations of H-1s and Ge-(4s, 4px, 4py, and 4pz) orbitals have occurred at deep valence band. The termination of π bonds leads to the opened energy gap of 2.01 eV in the H-functionalized system that belongs to the p-type semiconductor. The enriched properties of the H-functionalized system identify that the H-functionalized system...

The antimicrobial activity and chemical composition of Elsholtzia blanda (Benth.) Benth. essential oils in Lam Dong Province, Viet Nam

Nguyen Van Ngoc*, Hoang Thi Binh
Abstract | PDF
This study aimed to assess the chemical composition of essential oils of Elsholtzia blanda (Benth.) Benth. in Lam Dong Province, Viet Nam, and evaluate their biological activities. Essential oils obtained by hydro-distillation of the aerial parts of E. blanda were analyzed by gas chromatography-mass spectrometry (GC-MS). Thirty-one constituents were identified in the oil, and the essential oil was predominantly monoterpenoid, with camphor (25.14%), camphene (22.64%), a-Pinene (11.53%), and cineole (9.89%) as the four most abundant constituents. The evaluation of antimicrobial activity using the agar wells diffusion method showed that the essential oil in all concentrations was active against the Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli), and pathogenic yeast (Candida albicans), they are most sensitive and resistant to S. aureus strain.

A Vietnamese benchmark for vehicle detection and real-time empirical evaluation

Truc Trinh, Khang Nguyen*
Abstract | PDF
The current situation of traffic in Vietnam has many outstanding problems, especially traffic congestion, since the supply of infrastructure has often not been able to keep up with the growth in mobility. Thus, proposing monitoring plans to support authorities to make suitable and prompt decisions has always received large attention from the community. Meanwhile, applying information technology, especially advanced models which could process or analyze traffic data in real time is recently considered to be a priority solution due to the time, accuracy, and cost saving that it can potentially achieve. Therefore, this paper outlines research on three advanced real-time object detection methods: YOLOX, YOLOF, and YOLACT and the development of the newest Vietnamese traffic dataset named UIT-VinaDeveS22. The work contains both theoretical and empirical analysis,  which are expected to create premises for further studies into addressing problems such as traffic density management, traffic separation, and traffic congestion.