Vitamins C (L-ascorbic acid) and E (α-tocopherol) are essential micronutrients and antioxidants in feeds for various aquatic animals. This review compiles and analyzes the studies that focus on the effects and interactions between vitamins C and E on the growth, health, and body composition of different aquaculture species. As can be seen, vitamins C and E are indispensable nutrients for almost all aquaculture species. Information on their nutritional requirements and effects on aquatic animals has been examined and limited to several aquaculture species. Numerous studies have shown the vital roles of vitamins C and E in antioxidative functions. However, many other studies have also indicated that supplementing vitamins C and E in diets positively affects the growth performance, health, and body composition of aquaculture species. The review summarizes the documented findings related to the roles of dietary vitamins C and E in aquaculture. This study provides valuable information for nutritionists, feed mills, and other related institutions, as well as the effective use of these vitamins in the aquafeed industry.

Bacterial wilt disease, caused by Ralstonia solanacearum, causes significant loss to cucumber production in the Mekong Delta. In this study, the antibacterial activity of 95 strains against Ralstonia pseudosolanacearum strain T2C-Rasto was tested by the agar well method. Under laboratory conditions, three Trichoderma strains involving DN7.5, DN2.6, and DN30.7 showed strong inhibitory activity against Ralstonia pseusolanacearum strain T2C-Rasto with effectiveness of 74.29, 67.63, 67.63%, respectively. Under In vivo conditions, Trichoderma strain DN7.5 showed the highest effectiveness against Ralstonia pseusolanacearum strain T2C Rasto, reducing disease incidence by 26.67% after 14 days without affecting cucumber plant growth. The ITS (internal transcribed space) + 26S rRNA gene region of Trichoderma strain DN7.5 showed 98.13 - 98.38% sequence similarity with ITS sequence of Trichoderma asperellum strains (MF363050.1 - OM515036.1). Generally, Trichoderma strain DN7.5 has the potential for further research on the mechanisms of suppression against Ralstonia pseusolanacearum strain T2C-Rasto.

Today, with the development of science and technology, products using chemical-based fragrance, medicine have become increasingly popular, raising concerns about potential impacts human health. This study aimed to extract essential oils from native bamboo leaves (Bambusa vulgaris). In addition, the study identified the biological compounds in essential oils and preliminary assessed the total terpenoid content in the samples, using α-ionone as a standard solution for the determination procedure. The essential oil content was 19.50 ± 6.2 mg/100 g. The bamboo leaf essential oil extracted from the fine grinding samples exhibited antioxidant activity against DPPH (2,2-diphenyl-1-picrylhydrazyl). Total silicate of the bamboo’s hydrosol was 0.81 mg/L. Essential oils were analyzed by gas chromatography-mass spectrometry, which identified a total of eight compounds. The components in essential oil were α-ionone, trans-β-ionone, hexahydrofarnesyl acetone, farnesyl acetone, n-hexadecanoic acid, hexadecanoic acid, phytol, 9,12,15-octadecatrienoic acid. The total terpenoid content was 0.06% in the finely grinded samples.

Papaya ringspot virus W (PRSV W) is a common aphid transmitted potyvirus, seriously affecting cucurbit production worldwide. This study conducted field surveys to collect PRSV W infecting cucurbit crops in Cu Chi and Hoc Mon districts, two major vegetable-growing areas of Ho Chi Minh City. A total of 48 samples representing sponge gourd, cucumber, bottle gourd, wax gourd, bitter gourd, and pumpkin were collected and tested by indirect ELISA-based serological assay, which detected PRSV in four samples. The indirect ELISA-positive cucurbit samples were then subject to bioassay to identify the type of PRSV, followed by reverse transcription polymerase chain reaction (RT-PCR) confirmation for the PRSV W type. Among all the symptomatic cucurbit samples collected and tested in this study, the highest incidence (27.3%) of PRSV W was recorded on the sponge gourd samples. The infected leaves’extracted total RNA was analyzed by RT-PCR with primer pairs SMK 8701(F)/3’UTR(R), and the PCR product was sequenced. The results revealed that the complete CP genome sequence of isolate PRSV W isolate HocMon (PRSV W-HM) was most closely related (polyprotein nt and aa identities of 93.3 and 95.1%, respectively) to the China isolate of PRSV W (GenBank KX6558741). Briefly, this study provides important insights for the accurate early diagnosis of PRSV W infection and developing effective disease control strategies to limit the spread of this virus isolate.

Sedimentation supplemented by flood is an essential source of soil nutrition in the lower Mekong River basin. This study evaluated the sediment deposited on fields during the 2022 flood season at the Plain of Reeds (PoR), Vietnam. The PoR is a region of soil with heavy acid sulfate. The selected research area was two provinces in PoR, Long An and Tien Giang. The dike system in this region comprises the complete-dyke and semi dyke. This study uses a new sediment trapping design to measure deposited sediment with particle sizes > 50 µm during the whole flooding season of 2022. Three location types were selected for measurement, including internal canal (InC), flat field (FF), and the raising bed (RB). We selected these three location types based on agricultural practices in this region. The deposited sediment in one flood season was at a mean of 1242.3 ± 1102.6 g/m2. There were observed differences between location types, in which the highest was found at the flat field upstream (2941.5 ± 500.8 g/m2), to the flat field downstream (1621.3 ± 141.2 g/m2), to the internal canal (987.5 ± 929.43 g/m2), and lowest at raising bed (119.2 ± 9.43 g/m2). Significant differences were found between the flat field upstream and the other three location types within the study area. Total N and P content of sediment were found at a mean of 9.08 ± 5.05 mg/g dry weight (dw) and 0.62 ± 0.21 mg/g dw, respectively. The data showed a significant amount of sediment, and its nutrient contents can be trapped during the flooding season in this semi-dyke system.