The study was conducted to determine the levels of antibiotic resistance and multiple antibiotic resistance of 150 Vibrio spp. isolates from white-leg shrimp (Litopenaeus vannamei) collected from Binh Dien Wholesale Market in Ho Chi Minh City. Ten antibiotics were used to test the resistance of Vibrio ssp. isolates including ampicillin, ciprofloxacin, chloramphenicol, doxycycline, gentamicin, kanamycin, nalidixic acid, streptomycin, tetracycline, and trimethoprim/sulfamethoxazole. Antibiotic susceptibility test results showed that the percentage of Vibrio spp. resistance to the above antibiotics was 92; 12; 0; 0; 3.3; 80; 3.3; 46.7; 3.3 và 18.0%, respectively. The percentage of multiple resistant isolates from two to five tested antibiotics was 88.7%. Especially, none of the isolates were sensitive to all tested antibiotics. The multiple antibiotic resistance (MAR) index value was 0.259 indicating that these isolates were exposed to high-risk sources of contamination where antibiotics were commonly used.

The study was conducted to evaluate the safety and effectiveness of a new attenuated Gumboro vaccine, MB-1 in Luong Phuong chickens. A total of 27,700 one-day-old Luong Phuong chicks were vaccinated with the MB-1 vaccine at a dose of 0.1 mL/bird at the hatchery. The results showed that the level of IBD maternal antibodies on the day of vaccination reaching an average titer of 4,857. The MB-1 vaccine virus was in the Bursa of Fabricius from 24 to 36 days old. The Bursa Lesion Score (BLS) was moderate; gradually increased from 0.67 to 3 points and decreased with signs of recovery to 2.33 points at 36 days of age. The Bursa Index at 21 days of age was 0.39% and decreased to 0.1% at 36 days of age. The humoral immune response to ND vaccination was high, reaching an average titer of 4,448 at 42 days of age. Especially, MB-1 induced a strong immune reaction leading to high IBD antibody titers and more uniformity, reaching an average titer of 3,632 with a low CV of 22%. In summary, the application of MB-1 vaccine at the hatchery would provide one-day-old chicks with early localization of the vaccine virus in the Bursa and rapid and uniform development of active IBD antibodies. The MB-1 vaccine did not affect the immune response of chicks to the ND vaccination and was safe for the Bursa when applied to commercial day-old broiler chicks at the hatchery.

High-pressure processing is an emerging technology in the food industry. The application of high-pressure processing has shown a huge potential for improving the physicochemical, microbial, and sensory quality of aquatic products. The inactivation of microorganisms and autolytic enzymes by high-pressure processing results in an extension of fish muscles’ shelf life. High pressure inhibits the formation of putrefactive compounds and maintains the hardness of fish muscles, resulting in higher sensory quality compared to untreated muscle over storage time. However, the drawbacks such as discoloration, protein denaturation, and lipid oxidation could limit the application of high pressure on fish muscles. Besides, the gel formed by pressure-induction or high-pressure freezing/thawing of aquatic is being investigated intensively to obtain the benefits of high-pressure processing on aquatic products.

Dinh Quan is a mountainous agricultural district in Dong Nai province, focusing on agricultural development. Estimating reference and current crop evapotranspiration, as well as irrigation water requirements, is an essential foundation for effective irrigation planning for some perennial fruit crops (mandarin, banana, and mango) to manage water resources in a reasonable and sustainable way. Applying the FAO Penman-Monteith equation combined with the CROPWAT model, reference crop evapotranspiration (ETo), current crop evapotranspiration (ETc), and irrigation water requirement (IWR) of some perennial fruit crops being cultivated mainly in Dinh Quan district (banana, mandarin, and mango) were estimated. The total amount of water required for irrigation in the year of mandarin, mango, and banana trees in the study area was determined to be 592.6 mm, 473.0 mm, and 976.4 mm, respectively, corresponding to 5,926 m3/ha, 4,730 m3/ha and 9,764 m3/ha. Based on this result, the annual irrigation water requirement of the study area was calculated to be around 46 million m3 for the cultivation of mango, banana, and mandarin, mainly in the dry season (accounting for more than 95%). With current farming practices and using water resources, if there are no effective management measures and solutions, it may lead to a shortage of water for future production, especially in the dry season.

Production is often affected by natural, economic and social factors, as well as the correlation between these factors that will lead to sustainability in agricultural production. This study aimed at identifying and analyzing the correlation among factors impacting on farming patterns in Ben Tre province. The Expert methods (KIP), Cronbach’s Alpha and Exploratory factor analysis (EFA), χ2- Chi-square and Binary Logistic analysis were applied to determine and to analyse the correlation among factors. The results identified 4 main factors (people, policies, economy and natural conditions) and 16 sub-factors. The factors such as salty influence, land use policy, financial support policy and experience were correlated with almost other factors. The factors such as influence of soil quality, policies on product consumption, market, selling price, technical level and labor resources were not much correlated with other factors. The factors such as drought influence, flooding effect, technical support policies, financial capacity, capital capacity and education level were correlated with a few other factors. The land use policy factor was closely correlated to other factors.

Cassava mosaic disease (CMD) is one of the most serious diseases that has caused heavy losses in starch yield. In vitro propagation from CMD disease-free cassava is the optimal method to produce healthy seedlings. Identification of a suitable growth medium for the development of ex vitro plantlets during the acclimation stage is an important step in order to obtain healthy plant. In this study, common substrates such as coir, rice husk ash, and vermicompost were mixed in different proportions to create formulations for the autotrophic stage of disease-free KM140 cassava plants. The parameters measured including plant height, number of leaves, stem diameter, number of branches, root length, dry matter ratio of leaves, roots, survival rate, and percentage of nurse stage cassava plantlets were evaluated. The results showed that cassava plants were transferred from in vitro to ex vitro environments gained a survival rate of 84.5% in coir substrate after 1 week. The growth medium contained a mix of 85% coir + 10% rice husk ash + 5% vermicompost was suitable for the growth and development of KM140 cassava plantlets. In this condition, the plantlets reached height of 38.8 cm with 22.0 leaves and the percentage of commercialisable plantlets reached 85.3%.

The objectives of the study were to evaluate the current status of paclobutrazol (PBZ) used for flowering treatment for durian cultivation in Tien Giang and Ben Tre provinces and to analyze residual PBZ in the soil as a basis for recommending the use of PBZ. In each province, 60 households were directly interviewed by prepared questionnaires. Then, 15 selected households with continuous use of the PBZ for at least 5 years in durian cultivation to conduct  soil sampling at depths of 0 to 20, 20 to 40, and 40 to 60 cm at the canopy edge and one-half of the canopy diameter for analysis of PBZ residue. The results of the study revealed that there were 65.0% of households in Tien Giang province and 18.3% of households in Ben Tre province using PBZ higher than the recommended level, viz., the average concentrations of PBZ used in Tien Giang and Ben Tre were 1,816 ppm and 1,240 ppm, respectively. The highest average PBZ concentration in the soil was taken at the canopy edge at a depth of 0 to 20 cm, reaching 1.036 mg per kg (Tien Giang province) and 0.480 mg per kg (Ben Tre province). There was no residual PBZ in the soil samples collected at one-half of the canopy diameter at a depth of 40 to 60 cm.

The objective of this study was to construct standing stem and commercial timber volume functions at the individual tree level of Melaleuca cajuputi plantations. The insidebark and outsidebark stem volume functions were constructed from 56 sample trees at the diameter classes of 4 to 16 cm. The appropriate volume functions are tested from five candidate functions. The applicability of the volume functions were tested from 10 trees that were not included in the construction of the volume functions. The research results showed that the function V = a + b(D2 * H)c was a suitable function to build the insidebark stem volume function of Melaleuca cajuputi. The function V = a + b(D2H) + c(DdHe) was a suitable function to build the outsidebark stem and commercial timber volume functions of Melaleuca cajuputi. The volume functions gave errors less than 5.0%. Compared with the insidebark stem volume, the average ratio for the outsidebark stem volume, insidebark and outsidebark commercial timber volume, and bark volume was 65.7%, 95.2%, 60.6% and 34.3%, respectively.