Vol. 13 No. 5 (2015)

The maize inbred lines, Mo17 released by the University of Missouri in 1964 and B73, released by Iowa State University in 1972 have been used in maize improvement programs for over 50 years in the US and other countries. These two maize inbred lines belong to two heterotic groups that are Reid Yellow Dent and the Lancaster. We have evaluated the adaptability and combing ability of the Mo17 and B73 inbred lines in Gia Lam, Ha Noi to improve the domestic maize germplasm. Study results showed that Mo17 adapted well in Spring-Summer season while B73 grew well in early Autumn-Winter season. Mo17 had good general combining ability (GCA) for yield and ear length over B73. Hybrid produced from Mo17 showed heterosis in ear length, while the crosses produced from B73 showed heterosis in ear diamter. Four lines, D1, D3, D6 and D9 with high GCA values can be used in hybrid breeding program. This pointed out that it is possible to maintain and utilize Mo17 and B73 inbred lines to enhance the local maize germplasm and promote maize hybrid breeding in Viet Nam.

This study was conducted to investigatethe heterosis of agronomical traits relating to flooding tolerance in 10 maize hybrids derived from 7 parental inbred lines. The flooding treatments were applied artificially at seedling stage (3 - 4 leaves) in field conditions for one week. There was positive relationship of root length, SPAD value, dry matter accumulation and flooding tolerance ability in maize plant. Positive heterosis was found for SPAD, dry matter accumulation and grain yield under flooding stress conditions. Better growth and higher SPAD value under flooding conditions of D1xD3, D1xD4 and D2xD5 might contribute to the higher yields of these hybrids compared with others.

Field surveys of entomopathogenic fungi were carried out in Pu Mat National Park from 2011 to 2013. A total of 18 strains of Isaria javanica were collected, isolated and identified of which 6 strains infecting Lepidopteran larvae, 8 strains infecting Hymenopteran adults and 4 strains infecting spider adults. Specimens were found in the leaf litter with 66.67% and on the leaf underside with 33.33%. A white to ash gray powdery layer covers some parts or most of the host body. Conidiophores are vertical single or branching; phialides cylindrical basal part, thin neck, 8.4-14.2x2.2-2.8 µm in size; conidia fusiform, sometimes cylindrical, smooth-walled, hyaline then turning cream, light gray orash gray whenmature, 4.5-7.4x1.4-1.7 µm in size. Colonies on PDA at 25oC are relatively fast growing with diameter 23.14 mm after 9 days. The conidia appear on the 3rd day showing white colourand then turning cream and to light gray or ash gray at maturity.

The current study was conducted at 20 commercial porker and broiler chicken farms in Bac Giang province to evaluate the use of antibiotic in breeding farm and analyze the persistence of antibiotic such as Oxytetracycline, Chlortetracycline, Sulfadiazine, Sulfamethazine, Doxyciline and Tylosine in collected food samples. The results indicated that, the management was not strictly causing unsuitable use of antibiotic for domestic animal in commercial farms; All of things, such as the selection of antibiotic, the dosage of antibiotic in prevention and treatment, the temporal stopping antibiotic before buying and the combination of antibiotic mostly depended on husbandry. More than 17 kinds of antibiotic were used in commercial farms, popular ones were Norfloxacine (60,0%), Tylosine (60,0%), Gentamycine (55,0%), Doxycycline (55,0%), Tiamuline (50,0%), Colistine (45,0%) và Enrofloxacine (40,0%). 50 percent of food sample of porker and broiler chicken were found at least one of antibiotic such as Tylosine (20 - 30%), Sulfadiazine (30 - 40%), Chlortetracycline (20-30%), Doxycycline (0 - 30%) and Sulfamethazine (10 - 20%). However, non of them were over permission critical.

A study was conducted to evaluated aerobic composting method for treating fish carcasses and duck waste on small-scale fish-duck integrated breeding farms at Phuxuyen district, Ha Noi city. The results showed that thermogenesisoccurred optimal and reached a peak at 74.4°C after 3 days. The fish carcasses were quickly resolved after 7 days and fully composted after 30 days. Esspecially, with the methods aerobic composting, dangerous pathogenic microorganisms, like Salmonella, were killed after 30 days and E. coli and Coliform were significantly reduced. In addition, the emission of toxic NH3 and H2S was reduced, contributing to lowering stress on environmental pollution and protecting public health.

Field and experimental studies have shown that co-infection of PRRSV and PCV2 in pigs were quite common and thus the interactions between both viruses in the host might be critical to the pathogenesis of the disease. The exact interaction mechanisms are unknown and remained to be elucidated. In this study, the expression of cytokine mRNA as well as Toll like receptor signaling molecules associated with innate immunity in peripheral blood mononuclear cells (PBMCs) from pigs infected with PRRSV and/or PCV2 were investigated. Cytokine mRNA and TLR signaling molecule expression were determined by quantitative real-time polymerase chain reaction. Co-infection of pigs with PRRSV and PCV2 led to up-regulated expression of IL-1β and IL-10 mRNA and down-regulated expression of TNF-α and IL-6, IFN-α and IFN-β in PBMCs of pigs co-infected with PRRSV and PCV2. An increased expression of CD14 mRNA was noticed in pigs co-infected with PRRSV and PCV2. A down-regulated expression of IRF-1 and IRF-3 mRNA might also suppress the expression of IFNs that leads to the enhanced replication of PCV2 in pigs co-infected with PRRSV and PCV2.

In the present study, we have successfully developed a transformation protocol for a rice variety Taichung 65 mediated by Agrobacterium tumefaciens with high efficiency, easy manipulation and reduction in labour work. In the protocol, we have optimized all steps of transformation, standardized components of culture media and presented several manipulation experiments. Experimental results have shown that using petri dishes with high edge (15 mm) and exposing explants not only increased the rate of callus formation, but also enhanced the size and quality of calluses. Using bacterial suspension at density OD600nm = 0.1 was optimal with high GUS expression in callus (81.25%) and low contamination. During the selection phase, transformed calluses grew better in petri dishes with high edge (15 mm) and exposing explants. Checking for the presence of R4 promoter at the molecular level showed high frequency of regenerated plantlets carrying the transgenes (up to 90.24%). GUS expression in different tissues of transgenic plants indicated the high activity of promoter R4, leading to initiate transcription and synthesis of GUS enzyme. Analysis of T1 plants confirmed the stable inheritance of transgene to the next generation.

Treating cherry tomato flowers with exogenous NAA and GA3 singly and their combination at anthesispromote fruit development and fruit retention. Treatment with NAA alone at 20 mg/L significantly resulted in higher fresh weight, length, diameter and fruit yield compared to contro whereas treatment with GA3 at 5, 10 and 20 mg/L did not change fresh weight, fruit diameter, fruit length and fruit yield. Combined treatment of NAA 10 mg/L + GA3 10 mg/L gave the highest fruit weight, fruit diameter, fruit set, fruit number per bunch, bunch weight andfruit yield ascompared to control.

New products from Gac (Momordica cochinchinensis Spreng.), an indigenous fruit of Viet Nam have been recently found in the world wide markets as the seed aril part of the fruit contains a high content of lycopene and beta-carotene. These carotenoids are currently in special demand as they are natural antioxidants with potential to prevent cancers. The present study aimed at developing processing and conservation methods for the production of powder from Gac arils. The process development focused on the selection of drying temperatures to minimize the degradation of the carotenoid after processing. The result showed that 600C is the most suitable temperature. Gac powder dried at 600C had bright red color, typical odor, and slight loss of carotenoids. Gac powders dried at higher temperaturers (70, 80, 900C) had darker colors and considerable losses of carotenoids. The ones dried at 80 and 900C lost the typical odor but a burnt smell. In addition, the final moisture content of gac powder was increased along with the increase of drying temperature.

Hypocotyl explants of cotton (Gossypium hirsutum L.) cv. Coker 312 were transformed with Agrobacterium tumefaciens strain EHA 105 containing the GNA gene under the control of RSs1 promoter and selected on callus initiation medium containing kanamycin. Somatic embryogenesis was promoted in the surviving calli. Plantlets were recovered from putative transgenic embryos. Polymerase Chain Reaction (PCR) and Southern blot analysis were used to confirm the integration of GNA transgene into the plant genome. Western blot result indicated the expression of the GNA gene in transgenic cotton plants.

Androgenesis is a phenomenon in which microspores are made to bypass the sexual pathway and follow the sporophytic mode of development to generate new plants without the intervention of fertilization under in vitro conditions. Micorospore culture provides an ideal system, with a large, relatively uniform population of haploid cells, for use mutant selection, genetic transformation and in studies on the molecular mechanism of induction of androgenesis and embryogenesis. This paper aimed at establishing a protocol for anther microspore embryogenensis in traditional variety of Brassica juncea (Dong Du mustard). Five haploid lines was created from anther microspore culture. The results showed that, medium and plant growth regulator concentration had a pronounced effect on androgenic response in anther microspore cultures of Brassica juncea (Dong Du mustard). The medium B5 is the most suitable for morphogenesis of anther microspores culture. The highest percent of embryogenensis (2,33%) was obtained B5 medium supplemented with α-NAA 0,5 mg/l and Kinetin 1 mg/l. MS medium supplemented with IAA 0,5 mg/l, BA 0,5 mg/ l, 3% sugar and 8 g / l agar was capable of regenerating seedling from embryos. MS medium supplemented with 1,0 mg/l BA was optimal for shoot multiplication with a rate of 3.94 after four weeks. MS medium with 0,5 mg/l α-NAA was appropriate for root induction in terms of root number per shoot (6.54 root/shoot) and average length of root (3.68 cm) after three weeks.

Rice is the most popular food crop in Viet Nam. However, information about rice varieties and their cultivation are mostly available in textbooks and printed documents. There has been no digitalized database of rice information and no database management system (DBMS) for rice data that users can search and retrieve the information online. This paper presents a new approach for searching and retrieving rice information from a rice database and from a system on the Internet. We have collected information from reliable data sources to build a database of popular rice varieties in some regions of Viet Nam. From that, we design a database management system that allows users to perform searching, retrieving, and making report in detail about rice varieties in a convenient and efficient way. The database can be shared to many users and the online DBMS allows one to do searching anywhere with computer and Internet connection. The success in building the database and the DBMS give users an efficient way to access to information quickly and reliably, especially for agricultural researchers, rice grower and rice consumers. Up to date, the software is the first database and the first online tool for rice information searching and management in Viet Nam.

This paper used the simple higher order shear deformation theory (S-HSDT) to analyse the static and free vibration of simply supported (diaphragm), elastic functionally graded (FG), rectangular, plates. Functionally graded materials (FGMs), although heterogeneous are idealized as continua with their mechanical properties changing smoothly with respect to the spatial coordinates. Poisson’s ratio is assumed to be constant, but their Young’s moduli and densities vary continuously in the thickness direction according to the volume fraction of constituents, which is mathematically modelled as power law function. The equations of motion are obtained using Hamilton’s principle employing S-HSDT. Navier’s solution is used to solve the equations of motion. The effect of variation of material properties in terms of gradation index, the effects of aspect ratios, thickness-to-side ratio on the bending, the stresses and the natural frequencies of FG plates are studied in this article. The numerical results are also compared with results available in the literature to validate theoretical model of the paper.

The minimum height of mesh according to standard TCXDVN9385:2012 was not clearlydefined. The aim of this study was to propose theheight of mesh-type air - terminationaccording tothe standard TCXDVN9385: 2012 to achieve high protection. When buildingsnot higherthan 20m, a mesh width of 5m x 10m and 10m x 20m can beinstalled at a height 16cmand21cm, respectively. If the height of buildings greater than 20 m rolling - sphere method,with 4 mesh type are 5m x 5m,10m x 10m,15m x 15m and 20m x 20m atminimum height of 5cm, 10cm,15cm,and 20cm, respectively, can be used..

Oxidative stress in root of soybean [(Glycine max (L.) Merr.] cv. DT84’ was induced by exposure to Pb2+ ion. The reactive oxygen species (ROS) products such as hydrogen peroxide (H2O2), superoxide anion radical (O2.-) were rapidly produced 6-12 hours after treatment with Pb2+. The enhancement of the ROS was closely dependent upon concentrations of Pb2+. An increase in content of thiobarbituric acid reactive substances (TBARS) - product of membrane lipid peroxidation, and the high percentage of injury (13.89-25.03%) indicated that the cellular damage was resulted from oxidative stress. The induction of superoxide dismutase (SOD) and catalase (CAT) in roots of soybean cv. DT84 as the defense response of soybean via these antioxidative enzymes reduced the concentration H2O2 and O2.- 24 hours following Pb2+ treatment, therefore, contributing to control oxidative stress in soybean roots.

This study was conducted to understand the current situation of the distribution of vegetables through market and supermarket system in Ha Noi, to analyze factors affecting it and to propose some solutions to develop the production and distribution of vegetables to reduce risks for producers. According to interviews with producers, 82.31% and 4.04% vegetables produced in Ha Noiwere distributed to marketsandsupermarkets, respectively. Households engaged in new-typecooperatives and enterprises supplied 90-95% of their products to supermarkets and canteens, while others in the Agriculture Cooperatives and Agricultural Service Cooperatives sold 90% of their products to markets. The distribution of vegetables through markets and supermarkets is achieved throughtwo mainstream channels in Ha Noi, however, they also have different advantages and disadvantages. The study indicatedthat it is necessary that all these channels exist in Ha Noi. The paper proposes four solution groups: (i) Innovatingplanning, encouraging and establishibglinkages, monitoringand supportingmarketingpromotion; (ii) Supporting the establishment of new-typecooperatives and enhancingthe management capacityfor actors in the production and distribution of vegetablecommodities; (iii) Investingmore infrastructures for the of marketsystem,and (iv) Strengtheningthe provision of information and helpingconsumers in identifying the origin of vegetables and benefits from the consumption of vegetables.

This study was conducted to determine the level of awareness, behavior and the factors influencing the willingness to pay for the safe vegetables (SV). Data were collected from 132 households in two districts of Gia Lam and Long Bien through structured questionnaires. Results of the study indicatedthat up to 67,4% of surveyed households have bought SV, however, therate of SV used in everyday meals was only about 15-35%. Currently, high prices and incredible quality are the main factors hindering buying decisions of consumers. 65,9% of respondents do not believe in the current SV stores. At the same time, the consumers’ understanding level of the SV and ability to distinguish SV and the conventional vegetables is limited. In addition, up to 93.2% of the respondents are willing to pay more if the vegetable is truly safe, however, the level of payment is less than 20%. Result analysis of logit regression model also pointed out that the level of willingness to pay of consumers depends on the age factor, experience inpurchasingSV, understanding the SV concept, the awareness of the SV’ benefits and price sensitivityof consumers.

Evaluating financial health of commercial bank system is a key factor in risk management and economic forecast because it is a capital cycle of economy. This article used statistical description to evaluate fininancial situation of banks listed in Viet Nam stock exchange via asset growth, credit growth and earnings after tax as well as bad debt rate - factors significantly influencing banks’ performances. Then, Altman Z’’ score was used to forecast bankruptcy possibility of Viet Nam commercial bank system via financial reports of 39 commercial banks in the 2008-2013 period. The results show that Z’’ was in the safe range, volatile in the given period and signigficantly different by capital size. The 2 groups with highest and smallest capital size have Z’’ which is higher than that of the 2 others.

The aim of the present study was to assess the economic efficiency of slow release fertilizers (SRF) in sedge production in Nga Son district, Thanh Hoa province. Data was collected from 34 and 87 households with and without SRF usage, respectively, in summer crop of 2014. The indicator used to measure economic efficiency was value added (VA) in the value chain analysis (VCA) in accordance with household economics. Partial budget analysis (PBA) was utilized to clarify the differences in VA between households with SRF and without SRF usage. It is found that the application of SRF (N: P: K = 17: 7:10) at 700 kg.ha-1 with supplementary fertilization of 70kg super phosphate yielded in highest economic return. Two-way sensitivity analysis with various sedge price and productivity scenarios confirmed the stability of the practice. Therefore, tt is strongly recommended that this practice should be used in sedge production in Nga Son, Thanh Hoa.

Quá trình sinh mạch, sự tạo thành mạch máu mới từ những mạch máu cũ, là một quá trình thiết yếu cho sự phát triển của các mô, cơ quan, quá trình làm lành vết thương, cũng như các quá trình gây bệnh. Để nghiên cứu cơ chế của quá trình sinh mạch, việc lựa chọn mô hình nghiên cứusao cho phù hợp rất quan trọng và đôi khi không dễ dàng. Bài tổng quan này giới thiệu một số mô hình in vitro phổ biến cho nghiên cứu quá trình sinh mạch, đặc biệt chú trọng nghiên cứu quá trình biệt hóa hình thái của tế bào nội mô, bao gồm các mô hình hai chiều và ba chiều. Phương pháp chế tạo, ưu nhược điểm của từng mô hình, cũng như sự phát triển của quá trình sinh mạch trong tương lai sẽ được thảo luận.