Vol. 13 No. 7 (2015)

Rep-PCR technique (Repetitive sequence primed PCR) with 3 sets of primers designed on the repetitive sequences of bacterial genome including the extragenic repetitive palindromic (REP), enterobacterial repetitive intergenic consensus (ERIC) and BOX element was used to assessthe genetic diversity of 22 Pyricularia oryzaeisolates isolated from blastinfectedrice plants collected in 2012spring season in the Red River Delta of North VietNam. PCR using REP primers (REP-PCR) produced polymorphic bands from blast fungus isolates. Rep-PCR analysis showed thatblast fungus populations in this region aregenetically diverseas previously reported. No clear correlationexistedbetween fugus groups based on Rep-PCR analysisand other characteristics such as the color of the fungal culture, location of collection,and isolates.

In the current research, we evaluated growth and some characteristics of four red-fleshed and one white-fleshed dragon fruit varieties. All varieties had high survivalrate and grew well in the first year. Among the varieties testedwhite-fleshed varietyT-TQ and red-fleshed variety TL4 had 100% plant survival and reached the collumn peak at 192 and 207 days after planting,respectively. The chlorophyll a, b, a+b content per gram of stem, and a/b ratio of all varieties were very low with 2 -3 x 10-2, 5.16 –6.06 x 10-2, and 1.01 –1.22,respectively. These results indicated that all tested varieties prefer high sunshine. Anatomical analysis of stems showedthat all varieties have high water, mineral, and carbohydrate conductance, of which T-TQ and TL4 had highest number of largebundle sheath and total bundle sheath with 41 and 56,respectively.

The experiment was conducted to invetsigate the effect differentvermicompost levels on growth and yield of ĐTL2 rice variety grown in 2013 and 2014spring seasons atVietnam National University of Agriculture(5, 10, 15, and 20 tons/hain 2013 spring season and5,10, 15, 20and25 tons/hain 2014 spring season).The experiment was arranged in a randomized complete block design (RCBD) with three replications. No significant differencesin agronomic characteristicssuch as growth duration, number of leaves per main stem and effective number of tillers per hill were found withincreased levels of vermicompost dose. However, increasing levels of vermicompost exerted positive effect on physiological characteristics as SPAD index, leaf area and dry matter. Significant yield increase was observed at 10 tons per hectarebeyond which yield increment was insignificant. Highest net income (VND27,596,000per hectare)was obtained in 2014 cropping season with 10 tons vermicompost per hectare. The yield of ĐTL 2 rice variety depends onvermicompost dose expressed in thefollowingregression,y = -0.075x2+ 2.472x + 41.01 with R²= 0.522and optimal vermicompost dose was estimated at16,4 tons per hectare.

Porcine Epidemic Diarrhea (PED) is a serious and contagious swine disease caused by a virus ofCoronaviridaefamily. PED occurs throughout the year but more common in winter season and over 90% of cases occur in less than 7 day old piglets. In this study, 148 samples of faeces and intestines collected from PED-suspected pigs in the 3 provinces of Quang Tri, Thai Nguyen and Thai Binh during 2013 - 2014 werediagnosed by the RT-PCR method. The diagnostic results showed that 57/148 (38.51%) samples were positive with the PED virus. The nucleotide (nt) and deduced amino acid (aa) analyses based on the partial spike (S) gene sequencing showed that the present PED virus strains were closely related to the reference PED virus strains collected in VietNam previously, sharing 94.8 - 98.6% in nt and 93.5 - 98.8% in aa. The phylogenetic analysis revealed that all the present PED virus strains belonged to the group G1-1.

Acute hepatopancreas necrosis disease (AHPND) has been considered as a major constraint for the sustainable development of shrimp culture industry. This study was carried out to examine in vitroanti-bacterial effects of herbal extracts derived from leaves and seeds of myrtle (Rhodomyrtus tomentosa) on bacterial strains caused AHPND, Vibrio parahaemolyticusKC12.02.0, V. parahaemolyticusKC13.14.2, andVibrio sp.KC13.17.5. Results showed that although both myrtle leafand seed extracts had anti-bacterial effects against in vitro AHPND-causingVibriostrains, the myrtle seed extract showed higher antibacterial activities. The inhibition zone diameters of myrtle seed extract reached17,67 mm for V.parahaemolyticusKC13.14.2; 18,00 mm for V.parahaemolyticusKC12.02.0and 19,33 mm for Vibriosp.KC13.17.5. These results suggested myrtle seed extract can potentially be used as a material for development of herbal medicine for AHPND control.

Field fertilizer experiments were conducted to identifythe most effective dosage of compoundfertilizer with 6 different levels applied to Robusta coffee in basalt soil of Dak Lak province from 2012 to 2014. All experiment plotsapplied with compound fertilizer ofYara company were compared with 260kg N + 95kg P2O5+ 240kg K2O and 10 tons of manure (application at 2-yearinterval) applied forRobusta coffee as recommended by theMinistry of Agriculture and Rural Development (control 1). The results showed that application of 2,100 kg compoundfertilizersper haper year significantly increased soil fertility as evidenced by increasedcontents of total nitrogen, available phosphorus, and available potassium, Ca and Mg in soils. Moreover, the length of reserve branches increased by20%, 100 fruitweight by18%,andcoffee bean productivityper ha by21%, but fresh coffee/coffee beanreduced by14%. The rate 2,100 kg compoundfertilizers/ha/year also gave the highergross value (VND 139.46 millions/ha/year) andhighereconomic efficiency(profit of VND 62.52 millions/ha/year) in comparison with the recommended practice.

The degradation process in Nai lagoon was studied by analyses of the satellite images during 1975 to 2014 period and radioactive isotopes of 210Pb and 226Ra and the use of CRS model. Our results showed that, there was a dramatical decrease in areas of mangrove ecosystem and wetland ecosystem and increase in areas for aquaculture, saltmaking pans and settlement. Along with these changes there was a strong sedimentation of the lagoon, the rate being higher than that of other lagoons in the central region. This great sedimentation is a consequence of the land use transformation and this is one of the causes of degradation in biodiversity and natural resources in Nai lagoon.

In the present study, 3 -4 protocormsderived from meristem of red and white-pink Miltoniasp. were used as material source for all invitro culture experiments. Effect of MS medium concentration, coconut waterandBA alone or in combination with αNAA on protocorm formation and shoot growth were studied. After 90 days of culture, the results showed that half MS medium supplemented with 15% coconut water, 1.5 mg/l BA in combination with αNAA of 0.1 mg/l, 30 g/l sucrose, 8 g/l agar, 1 g/l activated charcoal,andpH 5.8 was the best for protocorm inductionand shoot growth (25.60 shoots/explant, height of 1.95cm). Half MS medium containing 0.1 - 1 mg/l αNAA or 0.1 - 1 mg/l IBA, 30 g/l sucrose, 8 g/l agar, 1 g/l activated charcoal,andpH 5.8 was suitable for in vitroroot formationafter 40 days of cultureandthe rate of shoot formation was 100%.Coconut fiber and fern fiber were suitablesubstratesfor plantlet growth in the greenhouse, with coconut fiber beingbetter in terms of number of roots/explant, root length andsurvival ratecomapred tofern fiber substrate.

OsCIPK15is a key regulator of starch degradation in rice due to submergence. This gene receives submergence signal via calcineurin B-like (OsCBL) proteins, which act as the Ca2+sensors, and whose role has yet to be established. In the present study, we compared the transcriptional regulation of CBLsin germinating rice embryos under water submergence. The trans-activation of OsCBLpromoters was tested by examining the effects of Ca2+. We used rice protoplasts to study the OsCBLs-OsCIPK15 protein interactions. We found that OsCBL4and OsCBL5were transcriptionally regulated under submergence.The Ca2+sensors OsCBL4 and OsCBL5 wereinvolved in this system and interactedon the plasma-membrane with OsCIPK15 in Ca2+dependent manner. Our results suggest that Ca2+signaling formed under submergence are inducedby OsCBL4and OsCBL5 which then interact with OsCIPK15 to activate genes involving instarch catabolism to provide energy for rice germination.

This study was carried out to optimize extraction condition of polyphenols from guava leaf. To obtain this goal, we used a response surface methodology to optimize extracting conditions of polyphenols. Four main factors affecting on polyphenol extraction conditions from guava leaf were investigated, including: Temperature, time, solven-material ratio, and solvent concentration. Research results showed that the optimal extraction conditions of polyphenols from guava leaf obtained as follow: Temperature of 90oC, time of 76.5 mins, a solvent-material of 70/1 (ml/g), and a ethanol concentration of 44.3%. At optimal extraction conditions, polyphenol content achieved 233.76 mg GAE/g of dry basis. Polyphenol extract from guava leaf obtained at the optimal condition exhibited high antioxidant activity based DPPH free radical scavenging ability with an IC50value of 2.1 µg/ml. Our research results indicated potential of using guava leaf as promisisng resources for extracting natural antioxidants.

Southern rice black-streaked dwarf virus-SRBSDV isa new virus species of the genus Fijivirusin the family Reovidae which caused serious rice losses in tens ofmillions of hectares throughout southern China and northernandcentral Vietnam during2009-2010period. To developsensitive and specific antibody for the diagnosis of SRBSDV based on ELISA method, a DNAfragment, namely P10.1, of the SRBSDV S10 segment, that encodes a highly-antigenic polipeptide, was cloned and expressed in E. coli.P10.1 consistingof525 nucleotides was cloned into vector pGEM®-T, then inserted into the expression region of pET28a and transfromed into E.colistrainRosetta to express recombinant polypeptide. Polypeptide fused with His-tag was expressedat 37°C,for16hwith 1.0 mM IPTGinducer. Using Ni-NTA chromatographic column recombinant polypeptide of about 35 kDa from cell extractswas purified. The purified polypeptide will be used as antigenfor inducing specific antibody against outer capsid protein of SRBSDV.

The novel properties of nano metals including iron nano havemadethem a source of new materials which areapplied in a various fields inindustry, agriculture and medicine. However, the effects of iron nano on plant tissue culture have hardly been investigated. This study was conducted to determine the effects of individual iron nano with concentrations from 0 - 35 mg/l or in combination with Fe-EDTA on the growth and development of Chrysanthemumsp. cultured in vitro. In vitro Chrysanthemumshoots (2 cm high,2 pairs of leaves) and Chrysanthemumstem segments (2 node/segment) were used as the source materials for this experiment. After 30 days of culture, all shoots from stem segments on iron nano media (0 - 15 mg/l) appeared interveinal chlorosis with chlorophyll content of leaves significantly lower (from 8.433 to 24.667 μg/cm2) in comparison to shoot-inducing MS media shoots (39.567 μg/cm2). The combination of iron nano and Fe-EDTA, in contrast, showed better results. Shoots developedwell withoutinterveinal chlorosis. After 1 month of culture, all parameters of shoots on media supplemented with 15 mg/l iron nano were highest. On the other hand, the replacement of Fe-EDTA with iron nano affected the root morphology but did not promote the growth of Chrysanthemum(in comparison to the control). Roots in these medium were small and had less root hair than the roots of Chrysanthemumplanletson iron nano combined with Fe-EDTA media. 10 mg/l iron nano and 35 mg/l Fe-EDTA appeared as the best combination for the growth of Chrysanthemumplantlets.

Laccase enzyme is a multicopper enzyme of the lignolytic enzyme system which has capability to oxidize diphenol and related compounds. It is widely used in processing of agricultural by-products andinwater treatment. This study was conducted to isolateand screen fungal strains which have laccase activity from the natural decaying wood samples. Samples of decayed woods were collected from different locationsandthe fungi were isolated, cultured and purified. Test for presence of laccase and enzyme activity were used to screen laccase-producing fungi strains withthe high laccase activity. Five fungal strains, designated as BN1, BN2-1, BN2-2, DA3-1 and BV1 were isolated, cultured and morphologically described(colonies, mycelium and spores). These strains showed highlaccase activity withBV1 expressinghighest activity(247.20 U/ml) and highest rate of enzyme activity per dry weight after 5 days of culture (E/m, 54.04 U/mg). BV1 strainwas tentatively classified as a species of the genus Meruliporia.

Browning isa major problem in fresh peach preservation. In this study, ascorbic acid and citric acid were used as anti-browning agents in pre-storage treatment in order to prevent the browning and prolong storage life of peach fruit harvested from Laocai Province. The research results showed that ascorbic acid and citric acid slowed down browning process and decay as well as physiological changes in the storage fruit. Different concentrations of acids were also tested and ascorbic 1,0% was proved to be the best option among the test combinations. Peach fruit which pre-storage treated with 1.0% ascorbic acid can be preserved up to 28 days.

After the Decision 1956 was issued by the Government, Nam Dinh province has paid much attention to and fully implemented the Scheme for vocational training for rural labors in the Province. In the past five years (2010-2014), although the percentageof rural labors trained increasedbutthere existed some limitations in the quality. Corrective measures have been employedwith limited sucess in terms ofpractical effects. This study focusedon evaluating the quality of vocational training for rural labors during the last few yearsto identifyfactors influencingthe quality of vocational training for rural labors in Nam Dinh Province and to recommend some effective solutions to improve the quality of vocational training for rural labors in the Province in the near future.

Business Intelligence (BI) is one of the most modern management systems in enterprises. This system helps the administrators in the use of data from many different sources to collect information and meaningful analysis of products, customers or markets..., all that are important for effectiver decision making. Application of BI in improving the accounting system in An Phu Hung, a SME in biscuit and candy production sector,has helped thecompany to solve the problems in information systems for business management, as well as reducing the labor cost, cutting the overtime issues for accountants.The exprerience lessons from this case study would give the managers and others who concern about BI a pratical view of BI appication in business management.

This research study reportsassessments of 250 farmhouseholdsin thetwo extremely difficult communesinThuong Xuan district, Thanh Hoa province on implementation of agricultural support policy for poverty reduction. Findings indicate thatthe majority of farmers expressed positive viewpoints on beneficiary identification process, accessibility, supports received and appropriateness of agricultural supportive policies for poverty reduction. Farmers also perceived that supportive policies have strong impacts on poverty reduction. However, poverty rate in the communes remainedhigh and reduced slowly. The situation was ascribedtoimproper beneficiary identification process, low accessibility of the poor, inappropriate planning, weak capacity for policy implementation and shortcomings in supportive policy design. The research also pointedout some measures to improve effectiveness and efficiencies of supportive policies for poverty reduction such as improvement of planning, renovating policy implementation process, propaganda of policies, enhancing implementers’ capacity, mobilizing resources and renovation of policy from free input subsidies to support a development of a full value change in agricultural productionandsettingout relief from supportive policies

This study was conducted to examine general information of dividend policy and the determinants of dividend payout ratio of listed firms in stock market in VietNam. To achieve these objectives, 154 firms listed in HoChiMinh stock exchange (HoSE) were selected and analyzed using descriptive analysis and multiple regression in period 2009- 2013. Results reveal that the profitability (ROE) and the firm’s size had positive significant effects on dividend payout ratio of firms in HoSE. These points can be used as reference to make investment decisions in HoSE.

With the great advantages of the natural conditions, economy and society, Uong Bi city has been developing some agricultural products on the local secialty goods,such as Early Phuong Nam Litchi, red-flesheddragon fruit, Yen Tu Gold Apricot Blossom, Yen Tu Apricot Wine, vegetarian diet, chicken soup ... Besides, Uong Bi also has the great potentials for tourism development, with emphasis onYen Tu spiritual Complex. Each year, the city receives over 2 million tourists to visit and take part in festivities. Taking that advantages, the city has initially built the model linking between the agricultural goods production with tourism development in order to mutuallysupport developmentindicating close interrelationbetween tourism development and agricultural goods production in Uong Bi city.