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Big-eyed bugs Geocoris spp. are a natural enemy species presented in many parts of the world that have been extensively researched because of the benefits that they bring to plants. In Vietnam, big-eyed bugs are found in many places, especially in farming complexes or large farms. In Ho Chi Minh City, Geocoris sp. was found in Pham Van Coi Commune, Cu Chi District, Ho Chi Minh City, with bug density fluctuations across seasons at an average of 5.33 ± 2.67 individuals per point. The density of the big-eyed bug in Cu Chi District was 03 times higher than the density recorded in Ham Tan District, Binh Thuan Province. Morphological and molecular-based COI genes identified the speciments from Cu Chi, Ho Chi Minh City, and Ham Tan, Binh Thuan are Geocoris ochropterus. From the research results, these two sampling sites will be selected to further evaluate the rate of natural increase of the big-eyed bug Geocoris ochropterus.

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and the third cause of cancer-related death worldwide. Potential microRNAs have been reported as biomarkers for early detection of HCC as well as novel molecular targets for HCC treatment. Various tissue expression profiles of miRNAs using three microarray datasets from groups in Asia (2), Europe, America (GSE147892, GSE21362, GSE74618, GSE40744) and multiple bioinformatics tools were integrated to determine the most significant miRNA groups to assist in the diagnosis of HCC. Statistical analyses identified at least 30 miRNAs with 17 up-regulated and 13 down-regulated in HCC-related tumor tissues. All the miRNAs also showed relevance to the hallmarks of cancer such as cell proliferation, invasion, metastasis, angiogenesis, metabolism, epithelial-mesenchymal transition and apoptosis. Expression levels of miRNAs observed in the European group showed up-regulation at 5–37% compared to both Asian and American groups. Interestingly, four miRNAs divided into two groups as miR-182-5p/miR-1269a and miR-199a/miR-422a were the most promising for diagnosis of HCC patients from healthy controls, with AUC values of 0.902 and 0.892, respectively. Results provided evidence of the correlation between potential miRNAs and HCC that could be useful for disease diagnosis based on in-depth analyses of large case numbers and cohort studies.

In this study, 25 endophytic bacteria were isolated and purified from rhizome, stem and leaf of the elephant grass, which were tested for their biological control properties. The number of living and dead brown plant hoppers were recorded and the mortality rate was analyzed by using Abbott’s formula. The results indicated that three endophytic bacteria including VBL1, VBT1 and VBT5 showed the highest biological control of Nilaparvata lugens at the mortality rate 46.95%, 55.02% and 55.02%, respectively after 8 days of screening and significant difference compared to other isolates (P

In Viet Nam, Pouzolzia zeylanica (L.) Benn is a native plant and has been demonstrated its applicability as a medical plant. Additionally, Pouzolzia zeylanica was used to control fly larvae during food processing due to insecticidal activity. We optimized the extraction of Pouzolzia zeylanica by ethanol at different conditions: concentration, the ratio of solid (material) - liquid (ethanol volume) (mg/ml) and the extraction time (hour). Results indicated that extraction yield was effected by all of the factors. The optimized extraction yield was 6.85% (Y) with ethanol concentration at 96 percent ethanol (Z1), the ratio solid to liquid is 1: 25 (mg/ml) (Z2) and extraction time is 4 days (Z3). We tested the efficiency of leaf extracts from Pouzolzia zeylanica and antifeedant activity against diamondback moth Plutella xylostella at different leaf extract concentrations. Results indicated that 80% mortality induced by those compounds was recorded on Plutella xylostella second instars at 30% leaf extract concentration and had significant difference compared to the control (P=0.0000); the leaf extract affected the ratio of pupation, adult emergence and antifeedant activity of P. xylostella (P=0.0000). The obtained results promise a potential of using Pouzolzia zeylanica as biopesticide in Viet Nam.

Parasitoids are important biological control of crop pests. In Vietnam, Cotesia vestalis is a native wasp species that has demonstrated its applicability as a natural insect pest enemy. Many adult parasitoids require food resources such as nectar and pollen to optimize their life cycles. Potential effects of yellow cosmos (Cosmos sulphureus), shrub verbena flower (Lantana camara), common zinnia (Zinnia elegans), and coriander flower (Coriandrum sativum L.) on the longevity and parasitism of C. vestalis were investigated. Results showed that nutrition resources from yellow cosmos (C. sulphureus) and shrub verbena flower (Lantana camara) significantly increased the longevity of C. vestalis in comparison with water (P < 0.001). Kaplan-Meier estimates of survival functions of female Cotesia vestalis exposed to different food sources indicated a significant difference in the treatments (P < 0.01). Male and female wasps feeding on Cosmos sulphureus, Lantana camara, and Coriandrum sativum survived significantly longer than wasps fed on water or Zinnia elegans. Parasitism efficiency of C. vestalis was tested on diamondback moth Plutella xylostella (L.) larvae for different food resources. Cosmos sulphureus, Lantana camara, Coriandrum sativum treatments gave the different mean number of emergence parasitoids per day compared to water treatment. Results implied that food resources from flowers benefitted the longevity of C. vestalis.

Recently, many studies have demonstrated the significant advantages of loop-mediated isothermal amplification (LAMP) based methods over serological tests and PCR for rapid detection of microbial pathogens. Here, a rapid LAMP assay was developed to detect the hepatitis B virus (HBV) from DNA, and particularly, blood samples from infected patients using a commercially available master mix and portable real-time fluorometer. The final optimized fluorescence-based LAMP assay provided significant amplification time of less than 15 minutes compared with over 1 hour for PCR and an opened tube LAMP system described previously. Results indicated that fluorescence-based LAMP assay was more sensitive than PCR as a rapid, sensitive, efficient, and highly reliable approach for rapid detection of HBV.

Vietnam is a tropical country with high diversity in insect distribution along the country. Rice, vegetables, maize, and beans are grown in all the country and share almost the same pest and parasitoids although the weather range is much different among the country. Long (2011) has listed about 300 species of parasitic braconids in agricultural landscapes in Vietnam and they are playing very important for biological control of insect pests. The short review provides some information on the diversity of parasitic braconids in Vietnam, molecular phylogenetic analysis of the world and the different behavior strategy.

The harmful wax moth larvae on honeybees, which decrease beekeeping productivity, are a worldwide concern. However, since beekeeping only has developed recently in Vietnam, identifying this insect has been neglected. Through morphological characteristics and molecular identification, this study accurately identified the harmful wax moth in three provinces: Long An, Binh Duong, and DakLak. Larvae samples collected in three provinces range in size from 15 - 20mm to 3 - 5mm, with the head lacking the particular features of large wax moths (Galleria mellonella) and the body milky white or light yellow. Males have an average size of 6 - 10mm x 1 - 2mm, females have an average size of 7 - 12mm x 2 - 3mm, and two pairs of wings have an average size of 5 - 7mm x 2 - 3mm. The results of molecular identification using the COI gene revealed that the wax moths found in the three provinces sampled refer to the species Achroia grisella and were of the same origin as the butterflies found in China. Based on morphological characteristics and molecular identification, the study provided more information on the honeycomb wax moth, which is found in three provinces: Long An, Binh Duong, and DakLak.

Nấm Magnaporthe oryzae được xem là tác nhân chính gây bệnh đạo ôn trên lúa và gây thiệt hại rất lớn về năng suất ở các vùng trồng lúa. Gần đây vai trò của microRNAs được mô tả là có liên quan đến khả năng chống chịu của cây trồng với các tác nhân gây hại. Trong nghiên cứu này, sự biểu hiện của osa-miR162a trên các giống lúa thuộc nhóm mẫn cảm và chống chịu với nấm M. oryzae trồng phổ biến tại Việt Nam được phân tích bằng kỹ thuật Real-time qRT-PCR. Mặc dù có sự đa dạng trong biểu hiện của osa-miR162a trên các giống lúa ở các thời điểm sau lây nhiễm (hpi) khác nhau, sự biểu hiện tăng của osa-miR162a trên các giống lúa chống chịu bệnh đạo ôn ở thời điểm 48 và 72 hpi thể hiện sự khác biệt có ý nghĩa thống kê so với các giống lúa mẫn cảm. Kết quả nghiên cứu chỉ ra rằng phân tử microRNA osa-miR162a hứa hẹn là một chỉ thị phân tử tiềm năng trong việc phân biệt tính kháng với nấm M. oryzae của các giống lúa trồng tại Việt Nam hiện nay.

The genus Neophyllaphis (Takahashi) (Aphididae: Neophyllaphidinae) is composed of 18 species; however, in the Americas only nine species have been reported previously. A new species, Neophyllaphis varicolor Miller & Halbert, was described in 2014 in USA. Colonies resembling those of this new species have been observed in Costa Rica on Podocarpus spp. In order to determine if N. varicolor is also present in Costa Rica, we sampled Neophyllaphis colonies from Podocarpus falcatus and P. chinensis. Additionally, we sampled individuals from Podocarpus sp. in Spain and Vietnam. DNA of each sample was extracted and used to amplify and sequence the cytochrome c oxidase subunit I (COI) and elongation factor I (EF-1α) partial regions. According to morphological characteristics, sequences comparisons done in GenBank and BOLD, and phylogenetic analyses, the colonies collected from Podocarpus spp. in Costa Rica and the colony from Vietnam corresponded to the species N. varicolor. To the best of our knowledge this is the first report of the presence of N. varicolor in Central America and Vietnam.

The study was conducted to evaluate the nitrate reduction in fermented mustard cabbage and determine the nitrate level during the fermentation process. A total of 10 samples of fermented mustard cabbage were collected from some retailers at Thu Duc market. The samples were used to determine the nitrate concentration using color compared with sodium salicylate. Then we isolated and cultured the strains of nitrate-reducing bacteria in a specific Giltay medium containing KNO3, as well as testing biochemical characteristics. The cabbage was fermented with additional nitrate-decomposing bacteria and the nitrate concentration was compared with the control treatment. The experimental results showed that the nitrate level of the 10 collected samples of fermented cabbage varied between 2.000 - 5.000mg/kg, exceeding the allowable level of the World Health Organization (WHO), during the three first days of the fermentation. The standard indicators were achieved after 4 and 5 days of the fermentation. In this study, we isolated at least 6 bacterial strains capable of reducing nitrate in a Giltay medium and selected two bacterial strains from others. The results of sequencing, identification and phylogenetic analysis based on NJ method showed that two strains of denitrifying bacteria are Bacillus aryabhattai.

The rice blast fungus, Magnaporthe oryzae, is the causal agent of severe damage in worldwide rice growing area. The resistance to blast infection has been determined by the relationship between the R resistant gene of rice and avirulence gene AVR of phytopathogenic fungi based on the “gene for gene” theory. The main objective of this study was to determine the presence/absence of AVR genes in the rice blast fungal isolates in Vietnam. The screening results of 30 fungal isolates collected from the south, the center and the north of Vie103-111tnam by PCR method indicated that the rates of presence/absence of the six avirulent genes varied clearly. In this study, AVR-Pik along with the CDS sequence of this gene (AVR-Pik CDS) was found to be nearly 99.67%, meanwhile the AVR-Pizt was only 36.67%. This result plays an important role in understanding the diversity of the AVR genes in M.oryzaethat could be helpful inthe selection and development of blast resistant rice varieties.

Magnaporthe oryzaeis a causal agent of the rice blast disease resulting serious damages in the production of rice worldwide. The early symptom of rice blast disease can be confused with those caused by other fungal diseases leading to many difficulties in efficient and effective disease management. Currently, identification of the rice blast fungus by using conventional method requires more time (at least 24 hours), labour and unreliability. An alternative method by using polymerase chain reaction (PCR) with the primers of Pot2 transposon known to reduce those factors for detection of the rice blast fungus will be done in this study. The results indicated the specificity of Pot2 transposon can be used for the rapid detection of both Magnaporthe oryzae and blast fungus infected leaf/neck in rice, but not in other phytopathogenic fungi. Therefore, PCR method has been considered as an alternative tool of diagnostic, particularly in-field detection of blast disease in practice.

MicroRNA (miRNA) is the class of short non-coding RNA, about 21 nucleotides in length. In general, miRNA functions as the post translational regulation in eukaryotic cells. Regarding its typical characteristics, especially in several cancers, with two prominent properties, namely the circulating and the stability of miRNA in bio-fluid, the miRNA is noticed as the potential biomarker in prognosis and early diagnosis of cancer.In the current review, we aim to introduce the molecular, the characteristics and molecular mechanism of miRNA bio-synthesis, and the activities of miRNA. Moreover, we tend to analyse and apply them as the potential biomarker for cancer. This will be the prerequisite to understanding and developing the miRNA study in Vietnamese patients.

Để hạn chế những tác động tiêu cực mà thuốc bảo vệ thực vật có nguồn gốc hóa học mang lại thì nhiều loại thuốc bảo vệ thực vật sinh học có nguồn gốc từ thảo mộc đã ra đời. Cây hoa ngũ sắc Lantana camara L. không chỉ được biết đến như một loại dược thảo được sử dụng làm thuốc chữa bệnh, mà hiệu quả phòng trừ côn trùng gây hại trên cây trồng của loài cây này đang được nhiều nước trên thế giới nghiên cứu. Trong nghiên cứu này, kết quả định tính alkaloid cho thấy dịch chiết cao thô lá cây ngũ sắc dương tính với 2 loại thuốc thử Mayer và Dragendorff. Đối với sâu tơ tuổi 2, hiệu lực tiêu diệt sâu tơ ở nồng độ 25% và 30% dịch chiết có sự khác biệt có ý nghĩa so với đối chứng (p = 0,0000), có khả năng ức chế quá trình hóa nhộng và vũ hóa của sâu tơ. Dịch chiết thô lá cây ngũ sắc còn có khả năng gây ngán ăn trên 90% sâu ở nồng độ 30% dịch chiết (có sự chọn lọc và không chọn lọc thức ăn). Vai trò của thuốc phòng trừ sinh học có nguồn gốc từ thực vật được thảo luận trong nghiên cứu này.