The water resources for cultivating crops have been restricted in recent years due to the impacts of climate change, especially intrusion of salinity in rice cultivation areas. Rice is known to be a susceptible crop to salt, so the development of rice varieties with the salty genotype is important and urgent. Therefore, the study is to evaluate the salt tolerance gene by SSR molecular marker on 40 improved rice varieties was conducted at College of Agriculture, Can Tho University. The study was selected 12 SSR molecular markers associated with salt tolerance QTL on 12 chromosomes, comparing between saline-tolerant control genotype (Pokkali) and saline-sensitive control genotype (IR28) with 40 rice improved varities/lines developed by Can Tho University. The results showed that there were two varieties lines (MTL 259 and MTL 308) that were classified into the same group with saline tolerance control Pokkali tolerance. Thus, these two varieties/lines may carry salt tolerance QTLs as Pokkali. This result is a base for further studies on salt tolerant rice varieties/lines.

Traditional rice in the Mekong Delta is only able to flower after exposing to a short-day period due to its photoperiod sensitivity. Therefore, deflecting the photoperiod of these good quality, good adaptability and salinity tolerance seasonal rice varieties is an urgent requirement now, serving production in the saline affected areas in the Mekong Delta. This study was carried out with a traditional rice rice variety: “Nang Thom Cho Dao”, by treating 1,000 seeds at the germination stage at temperature of 500C during 5 minutes. The treated seeds were planted and selected mutant lines from generation M1 to M5 in the greenhouse in the condition alternative long- and short-day lighting time. The results showed that mutant frequency was 2‰, the particle length changed in compared to the original variety (increased by 0.1 to 0.2 mm). Two of mutant rice lines were selected, photoperiod-insensitive, with short duration (

This study was conducted to determine the biological charateristics of flowering and fruit development of ‘Bi Ro hat lep’ durian in Tan Binh commune, Phung Hiep district, Hau Giang province from August 2018 to July 2019. An experiment was implemented using seven ‘Bi Ro hat lep’ durian trees at the age of 8-year-old, grafted on ‘Kho qua xanh’ root stocks.  Results showed that anthesis occurred within 12 days with a peak appearing in day 5, primarily at 16:00 to 17:00. The average fruit set rate was 87%. Fruit development process took place within 96 days after fruit set (DAFS). Young fruit abscission occurred mostly from 0-14 DAFS (42,2%). Durian fruit developed over three stages, i.e. slow (0-28 DAFS), fast growing (28-70 DAFS) and the mature-ripen stage (70-96 DAFS). Fruit flesh started to grow from 42 DAFS. Fruit reached to the maximum growing rate on 56 DAFS. At harvesting time, average fruit weight was 2,298.0±503.1 g, with an edible portion of 27%. The percentage of seedless fruit was 63%. Wet core, a kind of physical disorder, appeared at 70-96 DAFS. The phenomenon was observed on 14,8% of locule/fruit and 13,1% of aril.

The research is conducted to evaluate the effectiveness of organic fertilizer on soil chemistry and growth and yield of OM6976 rice variety. The experiment was set in a randomized complete block design of 5 treatments and 4 replications.. The results of soil analysis showed a statistically significant difference between treatments fertilized through experimental season. The rice yield of treatments applied to NPK + organic fertilizer is higher than 4% compared to control treatments (NT1). The results showed that the fertilizer formula for OM6976 rice variety in treatments NT2:60N:45P2O5:30K2O + 5 kg Risopla V; it gave the highest productivity and economic efficiency. In the Winter-Spring crop, the yield of OM6976 rice increased from 7,5 to 35,5% compared to the Winter-Autumn crop, Risopla V fertilizer and Risopla II foliar fertilizer showed the ability of improving soil fertility to help plants increase productivity clearly.

Nang Nhen rice, a traditional specialty variety of the Bay Nui mountains area of An Giang Province, is being degenerated. The restoration of Nang Nhen rice is carried out in order to retain good quality characteristics as well as productivity of this variety. By applying the SDS-PAGE technique and 2-acetyl-1-pyrroline (2AP) content, the three Nang Nhen lines having good quality characteristics as well as yield have been restored. The selected lines have short duration and good eating qualities, high protein content; low amylose and high yield potential. The aromatic characteristic of these lines was analyzed by using KOH (1.7%) method and the 2-acetyl-1-pyrroline content was analyzed by gas chromatography–mass spectrometry (GC-MS). Three lines NN12-2, NN13-5 and NN13-6 have short growth duration (112-119 days), high protein content (10.6%), and low amylose (14.72%), medium grain rice (6.3 mm), with good tolerance to pest and disease and stable fragrance.

The cultural similarities between the contemporary context and the era of Pham Quynh have given us an insight into his perspectives to gain solution-offering experiences in present-day society. This work sought to determine the key arguments in Pham Quynh's conception of intellectuals’ roles and missions in the national cultural innovation. Thereby, the present paper aims to rediscover the core values in his thought as well as draw valuable lessons.

Elephantopus mollis and Elephantopus scaber were collected from Bay Nui region (An Giang province) for three years (2016-2019). Their morphological characteristics, anatomical structures and medicinal powder were analyzed and compared with purpose of supplementing data to Elephantopus genus in Vietnam. The results showed that the morphological similarities of these two species occur at the sapling stage. At the mature stage, E. scaber has underground stem, purple flowers, and E. mollis has aerial stem, white flowers. In addition, these two species are able to be distinguished based on the size, thickness, tips shape or color of all leaves. The anatomical characteristics and the structure of the medicinal powder also showed differences in number and arrangement of xylem, and in covering trichomes of the two species at two stages (sapling and adult stages). Some by-products such as calcium oxalate crystals, essential oil-secreting cells and inulin crystals were found in the vegetative organs of E. mollis and E. scaber collected from An Giang province.

The study was conducted to assess the distribution of seagrass around Hai Tac archipelago, Ha Tien city, Kien Giang province. From two survey trips in September 2018 and March 2019, using the field survey methods of deep diving with SCUBA, photographing and sampling, the study has recorded 6 species of seagrass. These species were morphologically identified, namely: Cymodocea rotundata, Cymodocea serrulata, Halodule uninervis, Enhalus acoroides, Thalassia hemprichii, and Halophila ovalis. The seagrass beds occupied a surface area of approximately 30 hectares in Hai Tac archipelago. They mainly distributed in the Northeastern of Hon Doc, the East of Hon Truc Mon and the North of Hon Doi. In which, Thalassia hemprichii is always the most dominant species. In Hai Tac archipelago, the segrass’s shoots density was about 201 ± 34 shoots/m2; the average of coverage was 33.8 ± 15.1%; the average of biomass was 690 ± 267 g/m2; seagrass resource was estimated at 207 ± 80 tons. The research results are an important scientific basis for orienting the rational use of biodiversity and aquatic resources in the Southwestern of Vietnam.

In this paper, a connected p-median problem on complete graphs and complete bipartite graphs is mentioned. To solve this problem, several theorems and lemmas are given during research. Besides, linear-time algorithms are developed to solve the connected p-median problem on complete graphs and complete bipartite graphs.

Soil mesofauna was sampled in the rainy season (October 2018) and dry season (April 2019) from two typical habitats (seasonally submerged lands and seasonally unsubmerged lands) in Tram Chim National Park. As a result, a total of 42 species belonging to 32 genera in 28 families were recorded in that area. Of these animals, spider was the most diverse group with 24 species, followed by land snails and centipedes (each with six species), millipedes (four species) and earthworms (only two species). In particular, of which six spider and milipede species (belonging to six genera Hirudicryptus, Amaurobius, Hypsosinga, Chalcoscirtus, Orthobula, Bassaniana) were recorded firstly in Vietnam. In terms of distribution, there are no differences in species diversity between the two seasons, but there are significant differences in the number of species, the diversity index, and species composition between two habitats. It is suggested that soil huminity, pH and organic matter contents may be important factors influencing the distribution of soil mesofauna in Tram Chim National Park.

The aim of this study was to investigate the influence of extraction solvents (water, ethanol, methanol, ethyl acetate, chloroform, acetone and n-hexane) and extraction methods (conventional, microwave-assisted extraction and ultrasound-assisted extraction) on the extractability of phenolics, saponins and alkaloids compounds from cacao pod husk. The results showed that among seven extraction solvents tested, methanol and n-hexane achieved the highest amounts of phenolics and alkaloids, respectively but they were not significantly different from water (P

The expenditure and spending structure of tourists is an important indicator of the tourism industry's total revenue. The study points out the main factors for the expenditure structure of foreign visitors to Vietnam are: tourist destinations, service quality, thepurpose of travel, reference sources to decide tourism in Vietnam, demographic characteristics such as age group and career, visitors from continents, the number of visits to Vietnam. Factors are tested from the regression model based on Compositional Data Analysis (CoDA).

New Rural Construction Program is a key national program with the goal of comprehensive development of rural areas. After 10 years of implementation, it is necessary to assess the impact of the program, especially on people in rural areas. Four hundred and fifty-eight households in Hau Giang province were interviewed with respect to the commune groups with different levels of completion of the program criteria. The research results show that the new rural construction program positively affects income and socio-economic life in the study sites. By using propensity score matching method with the nearest neighbor matching, the research results show that the total income of the household after the program increases to VND 56,246 million/year at a statistical significance of 10%. For the scope/radius matching comparison method, the study showed that the total household income increased to VND 20,662 million/year at the 1% significance level.

Migration is a factor of the development process, especially in developing countries. The studies show that the main reason for migration is economics and the main type of migration is work migration. In Vietnam, with the rapid economic development process since Doi Moi period, the wave of migration has dramatically increased and this way not only contributed greatly to the development but also created many challenges for the social development. In this paper, the logit regression method was used  to estimate the probability which a household has at least one member migration for work  through the use of panel data of the Vietnam Household Living Standards Survey (VHLSS). Variables proposed in the research modelinclude demographic characteristics of the household head and the household characteristics as well as the economic status of the household. The results show that the factors belonging to the household of demographic characteristics as well as the household head have a strong impact on the trend of the household migration, especially the factor of remittance.

The study is aimed to analyze the moderating effect of corporate governance on the relationship between corporate social responsibility tranparency (CSR) and financial performance. The data was collected from 323 non-financial listed companies listed on Ho Chi Minh and Hanoi Stock Exchange from 2013 to 2017. The results showed that there was positive influence of the total CSR transparency on return on total assets, but the composition aspects had different influences on financial performance. In addition, three intermediate variables including the Board independence, the foreign ownership, and the audit quality played positive moderating role in the relationship between CSR transparency and financial performance. Based on the results, some policy implications were proposed such as increasing CSR transparency, attracting foreign investment, increasing the level of independent supervision of the Board and gradually considering the use of audit service supplied by BIG4.

Protection Motivation Theory was applied to find out determinants of farmers’ perception of flood risk in the Vietnamese Mekong Delta. The data were collected from direct interviews of 431 farmers in An Giang province, Hau Giang province and Can Tho city. The method of Dowling was used to measure farmers’ perception of flood risk. Perception of flood risks are considered in 5 aspects including health-disease, finance, production, social relations, and psychology. The results showed that 50.58% of farmers were awareness of flood risks. Three main factors significantly influencing farmers’ perception of flood risks in the study area included the age of the householdes, experiences of flooding and the loss of households in the extreme floods.

This study aims to analyze the factors affecting farmers’ decision to participate in contract rice farming in An Giang province. Descriptive statistics, T-test difference and binary logistic regression were employed. Data were collected via a survey of 211 contract and non-contract farmers in Thoai Son and Chau Thanh districts, An Giang province in October 2019. There was a significant difference between contract and non-contract rice farmers at 1% and 5% level such as farm size, specialization, cooperative and extension participation. The regression results showed that farm size, cooperative participation, attending extension services and trust had a significantly positive influence on the decision to enter into a contract. However, the delayed payment mechanism of the enterprises made a barrier eliminating farmers’ motivation to take part in contracts. The findings of the study provide useful insights for producers and policymakers to promote the comprehensiveness of contracts in the rice production and consumption chain.

The assessment of the degree of safety in seismic force calculation in designing high-rise buildings has not been mentioned in previous studies and in current standard TCVN 9386:2012 (Vietnam Institute For Building Science And Technology, 2012) which is applied for regular and irregular buildings. In normal cases, the base shear calculated by lateral force method is higher than the one calculated by response spectrum method. Therefore, it is necessary to determine the more efective and safer method. The article is aimed to propose the base shear balance between two earthquake calculation methods, namely lateral force method and response spectrum method according to ASCE 7-10 (American Society of Civil Engineers, 2010) in order to more accurately simulate the working of the structure while ensuring the structure working safely and saving materials.

The study was conducted to investigate the effects of heating time on gel properties of surimi from tra catfish and tilapia. Gel properties of two types of surimi were compared by using two heating methods: (i) direct heating at 90°C with different heating time 10, 20, 30 and 40 minutes; (ii) two-step heating, step 1 heating at 40oC with different time 20, 30, 40 and 50 minutes, and then continued step 2 at 90°C with different heating time 10, 20, 30 and 40 minutes. The results showed that surimi was heated by using two-step heating had higher hardness, chewiness and gel strengh compared to direct heating method. Different heating times were found for surimi from tilapia and tra catfish. With tilapia, heating time 30 minutes at 40oC (step 1) before increased to 90°C for 30 minutes was suggested, in case of tra catfish, heating times were chose 50 minutes at 40oC (step 1), and then increased to 90°C for 20 minutes. Surimi from tilapia was heated by using two-step heating had higher chewiness of 4,955 g compared to surimi from tra catfish with chewiness of 4,621 g. However, hardness and gel strength of surimi from tra catfish and tilapia were not significant difference when surimi were heating by using two-step heating.

The study was conducted to determine the appropriate probiotic content in white leg shrimp larvae applied biofloc technology on the growth, survival and productivity of postlarvae. The experiment consisted of 4 treatments, a control treatment without a probiotic supplement, and the remaining 3 treatments were added with probiotics with a content of 1, 2 and 3 g/m3/day. Sugar is used as an additional carbon source to create biofloc and to maintain C/N ratio of 15. The rearing tank has a volume of 500 liters, a density of 150 ind/L and a salinity of 30‰. After 20 days of rearing, the environmental factors in the treatments were in the suitable range for shrimp larvae to survive and develop. The mean length of shrimp postlarvae (PL-12) in the different treatments was not statistically significant (p> 0.05), ranging from 10.99 to 11.54 mm. The survival rate of PL-12 varied from 50.9 to 57.3% and yield from 76,407 to 85,977 ind/m3, in which the treatment of probiotic adding of 1 g/m3 was higher but the difference was not significant (p>0.05) compared to the remaining treatments, when PL-12 was shocked with 100 ppm formol and reduced 50% salinity, PL-12 of all treatments had a survival rate of 100%. Results showed that probiotic adding in rearing of white leg shrimp did not affect the growth and survival of postlarvae.

This study is aimed to assess the useability of fermented green seaweed Enteromorpha intestinalis (FGS) with minerals supplementation as feed to culture Artemia biomass. The first experiment was conducted to determine the suitable mineral concentration to add into FGS for Artemia culture. Different concentrations of mineral (0, 1, 3 and 5 g) were added to 1 kg of FGS with 3 replications per each and used to culture Artemia in 14 days. The findings showed that Artemia fed on FGS adding mineral at 3.0 g/kg obtained the highest length and survival rate. In the second experiment, Artemia was cultured in 21 days with 4 feeding treatments corresponding to the replacement rate of FGS at 0%, 25%, 50% and 100% of the industrial diet (ID), each treatment was repeated 3 times. The results showed that survival and Artemia biomass was highest in the 100% ID (85.67 ± 1.61% and 3.34 ± 0.28g). Artemia length was highest in 25% FGS replacement (7.60 ± 0.84mm) on day 14 of culture period. The fecundity of Artemia was highest in the 100% ID (84.43 ± 6.98 eggs/female) and lowest in the 100% FGS treatment (41.07 ± 6.73 eggs/female). The survival, growth and fecundity of Artemia during the experiment was always highest in 100% ID and 25% FGS replacement. The results showed the ability to replace fermented seaweed powder as food for Artemia franciscana with 25% replacement rate.

The study was conducted to isolate and to select nitrifying bacteria from sediment samples of whiteleg shrimp culture ponds. In this study, 121 nitrifying bacterial strains have been successfully isolated. As a result, the most common isolates were short rods, Gram-negative and motile. Among the obtained strains, TB7.2 showed the highest ammonia oxidation efficiency (39,02%) while strain TV4.2 performed the highest nitrite oxidation efficiency (27,8%) after 5 days of incubation. Strain TB7.2 and TV4.2 are Gram-negative, rod bacteria and have high potential for water treatment in aquaculture.

The research data was collected from 20 surveys in the Vietnam – China common fishing area of the Tonkin Gulf of Tonkin using a bottom trawls during the study period from 2015 to 2019. The number of species or groups of species encountered during surveys in the Common Fishing Area during 2015-2019 is very rich. The surveys found a total of 640 species and species groups, belonging to 293 genera and 143 families. The average yield during the study period was 52.18 kg/h. The average density of distribution of resources (CPUA- ton/km²) estimated from surveys during this period was 0.73 tons/km². In general, the mean stock density has decreased significantly compared to previous years. The average standing biomass in the common fishing area estimated from surveys during 2015-2019 is about 47,000 tons and the standing biomass yield is about 23,000 tons. The average standing biomass decreased by about 50% compared to the period from 2011 to 2013 (92,000 tons).

Structural equation modeling (SEM) has become a popular technique with a dramatic increasing in publications. Two main approaches to estimate structural equation models include covariance-based structural equation modeling (CB-SEM) and partial least squares structural equation modeling (PLS-SEM). The purpose of this study is to compare the testing measurement model results from CB-SEM and PLS-SEM, using a dataset of  consumer innovativeness in Ho Chi Minh city. The study shows that consumer innovativeness is measured with four different levels of consumer innovativeness, including innate innovativeness (II), domain-specific innovativeness (DSI), vicarious innovativeness (VI) and behavioral innovativeness (BI). All constructs were found to achieve acceptable reliability, convergent validity, discriminant validity, nomological validity, and model fit criterion. The study also finds that results from CB-SEM and PLS-SEM approaches are likely similar in measurement model and structural model testing; however, PLS-SEM has more advantages in some statistical analysis.

This study is aimed at examining the impact of local marketing components on tourists’ satisfaction to Can Tho city. Research data were collected through direct interview with 500 tourists using questionnaires. Exploratory factor analysis and binary logistic regression were used. The study results showed that six local marketing components affected tourists’ satisfaction to Can Tho city including power, tourism promotion, price, local communities, tourism products and place. In particular, Tourism promotion is the most influential component on tourists’ satisfaction to Can Tho city.

The most vital factor in Vietnam’s real estate marketing is the effective exchange of product information between vendors and customers. The purpose of this paper is to reveal the relationship between customer biological rhythms and their behaviors after that suggest a new solution. There were 1212 telephone surveys used in this research; of which,  862 were analyzed to develop a new marketing solution and 350 were used to test the suggested solution in the project. Therefore, the biological rhythms of customers played the most important role made up 100 points for each group of purchasers. After that, the paper proposed that the consumers should be called by the telesales representative in three periods (9:00-10:00, 10:00-11:00, and 14:30-15:30). The result of this research showed that the total percentage of effective marketing in the suggestive solution has been 2,5 times as high as one in the traditional method was used by the corporation.

Characteristics of zoobenthos in Hau River within Mai Dam town, Chau Thanh district, Hau Giang province were surveyed to provide baseline data for future impact assessment. Samples were monthly collected at 13 sites from March 2017 to March 2018. Three groups of zoobenthos including Annelida, Arthropoda and Mollusca were found. Zoobenthos composition varied monthly and was from 13 to 26 species. The lowest number of species was recorded in June, 2017 and the highest was found in October. Annelida accounted for 28% whereas Mollusca was 30.3%, and Arthropoda was 41.8%. Arthropoda was mostly dominated in density whereas Mollusca had lowest density. Biodiversity index H’ varied between 1.71 and 2.28. This result reflected that quality of water ranged from slightly pollution to pollution. Biodiversity index H’ seemed to be stable from November 2017 to March 2018 reflecting water quality of slight pollution as before Lee&Man discharging treated waste water to Hau river (March 2017). Sites within Lee&Man boundary had low H’ index, reflected for polluted sites. The result from this study was the important baseline data of zoobenthos communities for future based impact assessment due to socio-economic activities and development.

Studying on sour fermentation of dragon stem powder (Hylocerus undatus) by Bacillus spp. in anaerobic conditions was conducted with main ingredients including dragon stem powder combined powder of corn and rice bran flour. Treatments with three ingredients mixed at different ratio, as well as effect of time (1, 3, 5 and 7 days) and ratio of Bacillus spp. suspension solution (0, 3, 6 and 9%) with starter including 107 CFU/mL were conducted for evaluation of a process of fermentation. The monitoring indicators are bacterial density, pH value, volatile fatty acid content, soluble protein and ammonia content. The results showed that three components including the ratio of stem dragon fruit powder: corn flour: rice bran powder was 70%: 15%: 15% were fermented sour by Bacillus spp. suspension solution with starter including 107 CFU/mL in anaerobic conditions at 37°C for 3 days. The results were also illustrated that the product of lactic fermentation included a bacterial density of 9.33log CFU/g, pH 4.7, the lactic acid content reaching 6.46 g/L, 204 mg/mL of soluble protein and 0,483 g/kg of ammonia content.

Molasses, the by-product of sugar manufacturing process, generally comprises approximately 50% (w/w) of total sugars, but it is currently used primarily as an animal feed and as a raw material in alcohol production. Lactic acid fermentation can add value to molasses and reduce pollution. The objective of this study was to examine lactic acid fermentation from molasses by Lactobacillus acidophilus, Lactobacillus plantarum and Lactobacillus fermentum. The molasses was treated with sulfuric acid, added bacteria at a density of 1010 CFU/mL and fermented lactic acid at different conditions (molasses ratio, pH, temperature, incubation time and inoculum ratio). In this study, the suitable conditions for lactic acid fermentation from molasses were determined at the molasses ratio of 15% (v/v), pH of 6.0, inoculum ratio of 10% (v/v), temperature of 37oC and 30-hour incubation time and Lactobacillus acidophilus could create the highest lactic acid amount (16.7 g/L) among three strains.

The purpose of this study was to examine the research capacity of Can Tho University’s lecturers. The current status of research capacity of lecturers (n=198) was assessed based on basic criteria through questionnaires regarding the aspects of (1)awareness of lecturers on the role and importance of research activities; (2)motivation to perform scientific research; (3)self-evaluation on conducting scientific research capacity of lecturers; and (4)advantages and disadvantages of performing research activities. The results showed that lecturers have a proper awareness of the role and importance of doing research. The main motivations for lecturers to join scientific research were to improve their professional qualifications (93.4%) and support teaching (76.8%). In general, self-assessment of lecturers on their research capacity was mainly at fairly good level (41.1%), good (31.6%) and very good (5.2%). However, there were also some responses with poor level (3.11%). Support resources (administrative office and laboratories) are considered as main key factors affecting scientific research activities of lecturers. There is a need of policy to encourage the motivation and creating research environment. These are considered as potential solutions for improving research capacity and effectiveness of scientific research quality of lecturers and the University.