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Southern rice black-streaked dwarf virus (SRBSDV) causes severe epidemical disease on rice with the infected area up to millions of hectares in South China and North and Central of Vietnam. So far, there are no effective, cheap, quick, and practicable methods for diagnosing SRBSDV. The conventional RT-PCR technique is the most popular method for detecting SRBSDV with high accuracy. However, it is hard to apply this method for large-scale SDBSDV diagnosis because of the requirements of expensive reagents and instruments, as well as complex procedures. Meanwhile, SRBSDV diagnostic techniques based on antigen detection have outstanding advantages due to their low cost, easy manipulation, and wide application possibility. Today, there are still no commercially available specific antibodies to SRBSDV. In a previous study, to develop the SRBSDV diagnostic technique by the ELISA technique, a SRBSDV specific antibody was generated by a recombinant P10 envelope protein (66kDa), which has a titer of 1:5,000. In this study, we continued to study the production of SRBSDV specific polyclonal antibodies from small antigen–rich peptides from the SRBSDV P10 envelope protein. The resulting purified antibody can specifically bind to the P10 protein and at the diluted concentration of 1:100,000 it can detect SRBSDV in infected rice samples via the dot-blot technique. Our research results open up new opportunities for proactive antibodies to develop a SRBSDV membrane rapid diagnostic kit.

Reading comprehension is an important competence, not only a learning foundation for Literature or other subjects but also a prerequisite of thinking for each person to discover and manage their life. Teaching reading comprehension is a very important and outstanding requirement in the K-12 education reform at present and in the future. In particular, according to the requirements of the 2018 general education program, Literature needs to focus on developing students' language and literary abilities through reading, writing, speaking and listening skills. In this article, we propose solutions to contribute to improving the quality of teaching free verse reading comprehension for grade 10 students following competence-based approach.

Xanthomonas oryzae pv. oryzae (Xoo) causes severe bacterial leaf blight (BLB) disease to many Vietnamese major rice cultivars, including the TBR225. OsSWEET13 belongs to group III of the OsSWEET gene family encoding sugar transport proteins, which is considered one of the “susceptibility” genes (S genes) necessary for BLB disease. In this study, the rice cultivar TBR225 was determined to be susceptible to 19/20 Vietnamese Xoo isolates collected from the Northern provinces. Two of the three tested isolates (VXO_60 and VXO_96 isolates) were shown to up-regulate OsSWEET13 upon the Xoo infection of the TBR225 cultivar. The TBR225 OsSWEET13 promoter was isolated for sequencing analysis. The isolated DNA fragment was 615 bp in size, contained an effector binding element (EBE) PthXo2 that was recognized by the type III-secretory transcription activator-like (TAL) proteins of the Xoo. This promoter showed a similarity of more than 99% to the published OsSWEET13 promoter sequences (AP014967.1 and CP018167.1). Our findings are basic for the generation of highyielding rice varieties with resistance to BLB disease by genetic engineering in Vietnam.

Virus Southern rice black-striked dwarf virus (SRBSDV) disease caused serious damage rice growing areas in Northern and Central Vietnam over the past decade. While the application of SRBSDV diagnostic methods based on the Reverse transcription polymerase chain reaction (RT-PCR) technique was impossible due to technical complexity, simpler SRBSDV diagnostic techniques using specific antibody have not yet been developed in Vietnam. The biggest difficulty right now was the absence of commercial specific antibodies against SRBSDV. To develop diagnostic techniques by enzyme-linked immunosorbent assay (ELISA) for SRBSDV detection, in a previous study, we created antibodies against SRBSDV from the 66 kDa recombinant SRBSDV protein P10 expressed in E. coli; the obtained antibodies had a titer of 1:5000 dilution. Here, we continued to produce polyclonal antibodies against SRBSDV from small antigenic peptide (PASTTDVTHYGGY) derived from the P10 envelope protein, which was consevative in Vietnamese SRBSDV population. Titer of the purified IgG antibody was exmined using Dot enzyme-linked immunosorbent assay (Dot-ELISA) which showed a titer of 1:40000 dilution. The specific binding between anti-peptide IgG antibodies diluted at 1:40000 and the recombinant P10 protein in E. coli extraction was confirmed by using western blotting. In Dot-ELISA, our antibodies could distinguish between the SRBSDV-infected and non-infected rice samples. Our research results open up a new opportunity for developing the rapid diagnosis Southern rice black-striked dwarf virus membrane-type kit in Vietnam.