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The Relationship between People’s Livelihood Systems and Forest Carbon Stock

Ngo The An, Nguyen Thi Bich Ha

Received: 18-08-2014 / Accepted: 11-03-2015
This study was carrried out to determine the relationship between carbon (C) stock and people’s livelihoods. The analyzed results from 100 questionaires and group discussions at two villages which belong to Con Cuong district, Nghe An province showed that the livelihoods of the local people are very poor. The current land use types with high economic benefits resulted in low C stock. In contrast, the primary forests which arerich in C do not provide high incomes to the farmers. Policies on land management, forest protection, and forest plantation strongly impact people’s livelihoods. Due to the strict forest protection regime and the ban on shifting cultivation, farmer’s incomes have been significantly decreased at the strudy areas. Forest plantations are still financially supported by the government, but only a few better off households can afford to plant trees on their allocated forest land. Diversifying livehoods for local farmers by establishing an agroforestry model of field crops, such as cassava, inter-planted with tree crops such as fruit trees and Acacia sp., while continuing to protect upstream forests, could lead to the increase of C stocks and help poor farmers, but this measuere is only feasible if financial support is provided to the poor households.
A New Feature Sampling Method in Learning Random Forest for SNP Data Analysis

Nguyen Van Hoang, Phan Thi Thu Hong, Nguyen Thanh Tung, Nguyen Thi Thuy

Received: 22-10-2014 / Accepted: 20-12-2014
Recently, Genome-wide association studies (GWAS) have been successful in the identification of genetic variants that have effects in some complex diseases. Most GWA studies used single SNP (single-nucleotide polymorphism) approaches that mainly focused on assessing the association between each individual SNP and the disease. However, in fact, complex diseases are thought to involve complex etiologies including complicated interactions between many SNPs. Thus, different approaches are necessary to identify SNPs that influence disease risk jointly or in complex interactions. Random Forest (RF) method recently has been successfully used in GWAS for identifying genetic factors that have effects in some complex diseases. In spite of performing well in terms of prediction accuracy in some data sets with moderate size, RF still suffers from working in GWAS for selecting informative SNPs and building accurate prediction models. In this paper, we propose a new two-stage sampling method in learning random forests. The proposed method allows to select a sub-set of informative SNPs which are most relevant to disease. Therefore, it reduces the dimensionality and can perform well with high-dimensional data sets. We conducted experiments on two genome-wide SNP data sets to demonstrate the effectiveness of the proposed method.
Identification and Evaluation of Some Characteristics of Actinomyces Isolates as Potential Agents for Controling Anthracnose Disease on Momordica cochinchinensis

Le Minh Tuong, Pham Tuan Vu, Vo Kim Phuong

Received: 13-05-2015 / Accepted: 10-10-2016
The research was carried out in the laboratory of Plant Protection department, Can Tho University. The airmsof this research were to (i) identify the actinomycesisolates that were able to control anthracnose disease on Momordica cochinchinensisand (ii) examine their characteristics. Based on the culture, morphological, physiologicalandbiochemicalcharacteristics and sequencing of the16S-rRNA gene,five actinomycetes isolates were identified as five species: Streptomyces avellaneus, Streptomyces pallidus, Streptomyces vinaceus, Streptomyces showdoensis and Streptomyces exfoliatus.Chitinase activity assay tested on chitin medium showed that S. pallidus andS.vinaceusisolates hadchitinolytic activity, with the chitin lyses halo radius of 13.6 mm and 12.9 mm,respectively,at 7 days after testing. β-glucanase activity assay tested on β-glucanmediumindicated thatS.avellaneushadthe β-glucanolytic activity, with the β-glucanlyses halo radius of 6.0 mm at 13 days after testing.
Effect of Colchicine Concentration and Duration of Treatment on Polyploidy Induction in Shallot (Allium cepaL., Aggregatum Group)

Tran Thi Minh Hang, Pham Thi Minh Phuong, Nguyen Thanh Tuan, Phan Thi Ngan

Received: 09-11-2015 / Accepted: 11-03-2016
Local shallot (Allium cepaL. ), Aggregatum group) variety grown inKinh Mon, Hai Duong was treated with colchicine in order to produce polyploid materials for high-quality shallot breeding in Viet Nam. The research was carried out at Faculty of Agronomy, Vietnam National University of Agriculture. The shallot bulbs were immersedincolchicine solution with different concentrations (0,2%; 0,4%; 0,6%; 0,8%; 1,0%; 1,2%; 1,4%; 1.6%; 1,8%; 2,0%)for oneto tendays. The results revealed that colchicine treatment at concentration 1,0% for 6 days was most suitable for inducing tetraploid shallot plants with survival rate of 80%. Thepercentage of tetraploids was20% in total treated bulbs. Treatment at higher concentration and longer duration increased the percentage of dead plants up to 100%. Thirty six tetraploid plants of shallot were produced.
Methods of Principal Component Analysis and Cluster Analysis in Multi-Dimension Statistics Data Processing

Nguyen Huu Du

Received: 06-05-2014 / Accepted: 15-07-2014
A crucial issue posed in practical research is analyzing and processing of collected data. If collected data is large, examining the information will be relatively complex and troublesome. This article presented two efficient methods in multi-dimension data processing, principal component analysis and cluster analysis. These methods were successfully tested to analyze a set of data from a research project in agronomy.
Evaluation of Diversity and Characteristics among Common Beans (Phaseolus vulgarisL.) Exotic Germplasm in Vietnam Condition

Pham Thi Ngoc, Do Thi Du, Nguyen Thi Hue, Pham Thi Le, Vu Van Liet

Received: 11-07-2013 / Accepted: 07-05-2014
The agronomical characteristics and heat tolerance of twenty nine common bean accessions from USA were evaluated in two seasons: late spring and winter seasons in 2012 in Gialam, Hanoi. Most of the accessions showed short growth (55 to 80 days) suitable to cropping pattern of the Red RiverDdelta. There was a large variation in agronomical characteristics, such as plant height, number of leaves and branches, stem and flower color, fruit shape and grain size. The twining bean accessions had plant height from 180.5 to 306.0 cm while bush type accessions were three to five times shorter. Four accessions viz.CV44, CV54, CV59 and CV79 were heat torelant. Genetic similarity based on morphological characteristics and agronomic performance classified accessions into four separate groups with similarity coefficient of 0.18. Some accessions such as CV56 (107.52g), CV65 (145.91g), CV67 (116.28g), CV73 (191.35g), CV83 (117.28g), CV85 (117.77g) in green bean group and CV76 (52.0g) and CV77 (54.89g) in dry bean group had high yield in the winter season only. These accessions are potentialy useful for breeding programme with high yield.
Effects of Drought on Growth and Dry Matter Accumulation of Barley (Hordeum vulgare L.) at Seedling Stage

Nguyen Viet Long, Vu Thi Hong, Nguyen Van Loc, Nguyen The Hung, Dinh Thai Hoang

Received: 28-03-2014 / Accepted: 22-05-2014
This study was conducted to determine the effect of drought on several physiological and morphological traits of barley at seedling stage. Factorial experiment including 9 barley genotypes with constrasting salinity tolerance capacity at seedling stage, and 3 water regimes was laid out in a completely randomized design with 3 replications. Drought was imitated by maintaining the soil moisture contents during 2 weeks since 14 days after sowing. The data were collected for plant height, the number of leaves, the number of tillers, leaf area and dry matter accumulation. The results showed that drought at seedling stage significantly reduced plant height, number of leaves, leaf area, number of tillers and dry matter accumulation of barley genotypes. BCC884 and BCC438 were best genotypes for drought adaptation. Using the characterized salt tolerance varieties, the results in the current study was used to discuss the relationship between drought and salinity tolerance ability at seedling stage. This could be useful information to research on physiological and molecular mechanisms of tolerance to osmotic stress found in drought and salinity stress.
Study into Application of Relative Valuation Model for Listed Companies in Ho Chi Minh Stock Exchange

Nguyen Thi Hoang Giang, Bui Thi Hong Nhung

Received: 27-05-2013 / Accepted: 24-04-2014
As one of the two most popular valuation models in the world, relative valuation is closely related to empirical evidence of stock return predictability. Applying this model to 307 listed companies in Ho Chi Minh Stock Exchange (HOSE) using two multiples, P/B and P/E, the study showed that investment strategies using industry’s P/E is the most successful, while those based on P/B are not, despite various modifications of peer company choices. However, in evaluating the predictive power of these multiples, P/E appeared to be statistically insignificant and P/B had an unexpectedly positive correlation coefficient with stock price fluctuations. This result suggested critical implications in establishing stock returns predictors in the research context of Vietnam stock market.
Effect of Bioproduct of Purple Photosynthetic Bacteriaon Environmental Quality of Pond under Intensive Tilapia Farming

Do Thi Lien, Nguyen Thi Dieu Phuong, Nguyen Thi Bien Thuy, Do Thi To Uyen, Dinh Duy Khang

Received: 25-03-2014 / Accepted: 26-04-2014
The biological characteristics and classification of purple photosynthetic bacteria formulation consisting of three strains with high sulfide removal activity were studied. Of the three strains, two strains belong to species Rhodobacter sphaeroides denoted as QN71 and QN52 and the other to Rhodovulum sulfidophillum denoted as TH21. The use of purple photosynthetic bacteria formulation forclearly improved water quality of intensive tilapia farming pond environment. BOD3 concentration significantly reduced from 9.6-9.8 mg/l to 3.2-3.4 mg/l after 2.5 months, while BOD3 concentration gradually increased in the control. H2S concentration in water decreased from 0.03-0.04 mg/l down to 0 nilll and the concentration in sludge decreased from 5.4-6.67 mg/g to 3.5-4.5 mg/g. In two control ponds H2S concentration in water increased from 0.03 mg/l to 0.06 mg/l and in the sludge increased from 5.2 mg/g to 5.8 mg/g (DC1) and 6.4 mg/g (DC2). Using bioproducts of purple photosynthetic bacteria contribute to good effect to speed growth and development of intensive culture of tilapia.
Histopathological features of tilapias cultured in Nothern Vietnamese provinces naturally infected with Streptococcussp.

Truong Dinh Hoai, Nguyen Vu Son, Nguyen Thi Hoai, Nguyen Thi Mai Phuong, Nguyen Thi Hau

Received: 13-05-2014 / Accepted: 30-05-2014
This study was implemented to clarify some histopathological characteristics of tilapia naturally infected with Streptococcus sp. cultured in freshwater ponds in Northern Vietnamese provinces during summer of 2013. Infected tilapias (n=46) showing symptoms of dermal haemorrhage and exophthalmia were collected at 9 fish farms in Hai Duong, Ha Noi and Ha Nam provinces and examined for both gross lesion and histopathological signs. Internally, the most consistent gross findings were haemorrhage and swelling of liver, spleen, kidney, heart and intestine as well as pale coloured liver and splenomegaly. Fish occasionally exhibited the accumulation of fluid within the abdominal cavity, epicarditis, and peritonitis. Histopathological examination revealed systemic bacterial dissemination and infiltration of bacteria-laden macrophages. The cornea was damaged and invaded by bacteria. Haemorrhage, granuloma formation and necrosis were detected in the infected areas of the liver, spleen, kidney and gills. Microscopical examination confirmed the presence of severe congestion in these ograns, especially spleen and kidney. Brain lesions were present occasionally. The results indicated that infected fish exhibited obvious and systemic histopathology.Adverse environmental factors during the hot season played a certain role in the formation of lesions and outbreak of this disease.
Population growth of Small Brown Planthopper Laodelphax striatellusFallen (HOMOPTERA: DELPHACIDAE)

Tran Quyet Tam, Tran Dinh Chien, Nguyen Van Dinh

Received: 15-11-2013 / Accepted: 26-12-2013
The Small Brown Planthopper Laodelphax striatellus Fallen (SBPH) is a key insect pest of rice in Northern provinces. In addition to direct damage to development and productivity of rice, SBPH is a vector of viral diseases of rice. The study was conducted at the relative humidity of 85% and two temperatures, 250C and 300C with the food being 15-day old rice seedlings of variety Bacthom No 7. The results showed that at 250C and 300C SBPH’s life cycle was relatively short with 28.5 days and 24 days; the oviposition time with 9 days and 7 days; and average number of eggs per female 154.07 and 104.63, respectively. At 250C and 85% RH, SBPH’s the natural intrinsic rate (r) was relatively high (0.1194); Net reproductive rate (R0) was 52.07 and time for double population (DT) was 5.81 days. At 300C and 85% RH, SBPH’s the natural intrinsic rate (r) was relatively high (0.1294); Net reproductive rate (R0) was 32.91 and time for double population (DT) was 5.36 days.
Effects ofin vitroMutagenic Treatmentwith combination of EthylmethaneSulphonate(EMS) and Gamma Irradiationon genetic changesin Carnation(Dianthus caryophyllusL.)

Vu Hoang Hiep, Nguyen Thi Ly Anh

Received: 29-10-2013 / Accepted: 29-12-2013
The study on the effectsofcombined EMStreatment andgammaradiation on survival, growth, developmentandgenetic changes ofin vitro carnation (Dianthus caryophyllusL.)aimed at identifying effective methodstocreatematerialsfor carnation breeding.Stem segments with nodes of in vitro plantlets (cultivar “Princess”) were treated withdifferentEMSconcentrationsand gamma - raysirradiationdoses(EMS concentrationsfrom0.1 to0.4% andthe absorbed doseof gamma – rays from10-30Gᵧ).Eighttypesofshoot variants were obtained(A, B, C, D, E, F, Gand H).Inin vitrocondition, the height, number ofleavesandrooting abilityofthese shoot variantswerereduced graduallyin the following descendingorder:C> A> D> B> F> H>G.Thegrowth anddevelopmentofthese shoottypesin thenurserywere alsodifferent. The shoot type showed strongest growth, followed by typesA, D, F, B, and H. The type G did not grow and developinnurseryconditions. Some variantsoftheleafmorphology andcolor offlowers were isolated. The results showed that the rate of genetic changes was positively correlated with treatment dose. However, mutationrate increasedmainly intheundesirable types. The optimal treatmentdosewas 0.2% EMSand radiation of 20Gy. Thisdoseyieldedhigh survival rateandfrequency ofpotential varianttypesforbreedingnewcarnation cultivar.
Determination of Suitable Narrow Row Spacing for Hybrid Maize Variety CP333 on Degraded Soils in Bacgiang Province

Dinh Van Phong, Nguyen Nhu Ha, Nguyen Van Bo

Received: 05-08-2013 / Accepted: 22-10-2013
The experiment was conducted to identify suitable row distance for the hybrid maize cv. C.P. 333 on the infertile soil of Bac Giang province. The experiment was planted in two concecutive winter and spring crops of year 2010-2011 and applied with the following fertilizer rate:10tons manure+ 135 N + 90 P2O5 + 100 K2O per hectare. Results showed that the hybrid maize variety C.P.333 performed best when planted at row spacing of 50 cm with planting density of 70,000 plants per hectare. With this row spacing and population density, the hybrid maize showed highest LAI, low insect infestation, and higher yield in comparison with other planting densities in both cropping seasons.
The Current Situation and Economic Efficiency for Using Cultivative Land in Tu KyDistrict, Hai Duong Province

Dao Duc Man, Nguyen Tat Canh

Received: 05-09-2013 / Accepted: 23-09-2013
The study evaluated the curent status of agricultural land use models as well as economic effectiveness of land use types TheGAMS multipurpose mathematic model was used to determine land use typeswith high economic efficiency to serve as basis for developing land use guidelines until 2020 in Tu Ky district. In 2010, there were 29 land use formswithin three main land use types in the district. The economic efficiency of land use for rice cultivation was shown to be lower that land use for non-rice crops. Based on GAMS model with varying food production and investemnt as variables, potential land use types were proposed.
Apparent Digestibility of Some Commercial Feeds for Short Fin Pompano (Trachinotus ovatus)

Tran Thi Nang Thu, Nguyen Huu Ninh, Tran The Muu, TranThi Thap Hieu, Nguyen Tuan Dat

Received: 20-10-2016 / Accepted: 17-07-2016
The study was carried out from March to June 2015 at National Broodstock Center for Mariculture Species in Northern Vietnam (Center), Cat Ba, Hai Phong province, to evaluate digestibility of protein (ADP), lipid (ADL) and gross energy (ADE) of some available commercial feeds for pompano,Trachinotus ovatus, using indirect method with chromic oxidize (Cr2O3) 1% as inert marker. Pompano of 400g/fish were held in marine cage- culture system (3 x 3 x 3 m, six of each cage) at density of 10fish/m³. Three commercial aquafeed brands with different protein content,46, 50 and 51% were determined for their digestibility inpompano (abbreviated as D46, D50 and D51) with three replicates. The feaces were collected each day by stripping method before feeding the fish. Fish were fed by hand to apparent satiety, once daily at 9h. Feaces werethen pooled in sealed bottles and stored at- 200C until use. The results showed that ADP of D50 (71.34%) was lowest among experimental diets (P< 0.05), while that of D46 (76.42%) and D51 (77.52%) did not significantly differ (P> 0.05). ADL value of D51 was lower than that of D46 and D50 (P< 0.05). Result of ADE indicated that ability of pompano to digest energy from three commercial diets was similar (P> 0.05). The digestibility of protein and energy of three pellet feedsusedto test in pompano culture wasnot so highandthe quality of these feedsshould be further improved.
The Result of Evaluating Process Some New Hybrid Tomato Combinations at the Northern Coastal Areas of Vietnamin Autumnand Spring-Summer Season

Nguyen Hong Minh, Tran Thien Long, Nguyen Thi Minh

Received: 17-05-2013 / Accepted: 16-09-2013
A total of 22 new combinations of hybrid tomato were tested in 2011 autumn – winter (12 combinations) and 2012 Spring-Summer cropping season (10 combinations) at four locations in three provinces: Hai Phong, Thai Binh and Nam Dinh. Four hybrid combinations , T10, T12, T18 and T19 performed best in 2011 autumn – winter season and other four hybrid combinations, T12, T16, T19 and T26 showed high yield and low viral disease incidence in 2012 spring-summer season.
NghiêncứutínhđahìnhExon 14, gen MX ở mộtsốgiốnggàbảnđịacủaViệtNam

Bui Tran Anh Dao, Dong Thi Hong Lien, Nguyen Thi Phuong Thao, Daniel Desmecht

Received: 05-05-2013 / Accepted: 25-08-2013
Nghiên cứu tính đa hình của exon 14, gen Mx được thực hiện trên 7 giống gà bản địa của Việt Nam (bao gồm: gà Ác, Đông Tảo, H’Mông, Hồ, Mia, Móng và Ri). Kết quả cho thấy tính đa hình của exon 14 xảy ra tại hai vị trí (2032 và 2159). Sự thay thế A hoặc G tại vị trí 2032 của gen Mx có ở tất cả 7 giống gà bản địa được sử dụng trong nghiên cứu này. Trong cùng một giống đều có cả hai alen A và G, tuy nhiên, alen A (liên quan đến tinh kháng virus) có tần số xuất hiện cao hơn so với alen G (liên quan đến tính mẫn cảm với virus). Đặc biệt, tần số của alen A ở giống gà Ri và gà H'mong là cao nhất trong số 7 giống được kiểm tra (với tỉ lệ tương ứng là 80,91% và 74,04%). Phân tích so sánh các axit amin cho thấy sự thay đổi nucleotide A hoặc G tại vị trí 2032 sẽ dẫn đến sự thay đổi axit amin tại vị trí 631 của protein Mx từ Asparagine (liên quan tới khả năng kháng virus của giống) sang Serine (không liên quan tới khả năng kháng virus của giống).
Photosynthetic Characteristics and Dry Matter Accumulation of New Developed Rice Lines with Short Growth Duration

Do Thi Huong, Doan Cong Dien, Tang Thi Hanh, Nguyen Van Hoan, Pham Van Cuong

Received: 21-03-2013 / Accepted: 26-04-2013
The pot-experiment was carried out in the green house at the Faculty of Agronomy in autumn 2011 and spring season 2012 to evaluate photosynthetic characteristics, dry matter accumulation and plant growth rate of short - growth duration rice genotypes. Two lines, IL 3-4-2-7, IL 19-4-3-8 and control varierty IR24 were used in this study. At active tillering, heading and dough ripening stages, four plants of each line were randomly selected to measure photosynthetic characteristics, such as photosynthetic rate, SPAD value (an indicator of chlorophyll content), leaf area and dry matter biomass in leaves, stems and panicles. The results showed that there was no significant difference in photosynthetic characteristics and dry matter production between IL-lines and IR24. Plant growth rate (PGR) of IL3-4-2-7 and IL 19-4-3-8 from active tillering to heading stages was higher than that from heading to dough ripening stage. In contrary, the PGR of IR24 was the same at two stages. A significant and positive correlation between grain yield and photosynthesis rate at active tillering and heading stages was found in newly selected lines, whereas the significant and positive correlation between grain yield and photosynthesis rate at heading and dough ripening periods was observed for IR24 variery. Grain yield of lines with short growth duration correlated significantly and positively with PGR before heading stage, while grain yield of IR24 correlated significantly and positively with PGR after heading stage.
Research on Photosynthesis of Barnyard Grass (Echinocloa crus-galli (L.)Beauv)and Rice (Oryza sativaL.)

Vu Duy Hoang, Ha Thi Thanh Binh, Vu Tien Binh

Received: 11-11-2012 / Accepted: 19-02-2013
The pot experiment was carried out in the greenhouse to estimate the effect of different fertilizer levels on photosynthetic and physiological characters at active tillering, flowering and early ripen stage of barnyard grass (Echinocloa crus-galli (L.) Beauv) and the rice cultivar Khang dan 18 in both summer and autumn cropping seasons in 2012. Seeds of each species were sown in distinct pots containing 6 kg dry soil per pot. When rice and grass had 2 leaves, the plant was kept in single pot. There were three nitrogen levels, no nitrogen (N0), 0.1grN (N1), 0.12 grN (N2) with the same base of percentage N: P2O5 : K2O: 1: 0.5: 0.5 per one kg dry soil. The result showed that photosynthetic rate and dry matter accumulation rate of barnyard grass were higher than those of rice at all growth stages in both seasons, although stomatal conductance, transpiration rate and SPAD of rice were higher than those of barnyard grass. As increasing fertilizer, the photosynthetic rate, dry matter accumulation rate and nitrogen content in leaves were also increased in both rice and barnyard grass.
Effectiveness of Rice Straw Burrying with Microbial Products in Rice Production Following Organic Production Direction at Gia Lam, Ha Noi

Pham Tien Dung, Nguyen Xuan Xanh

Received: 15-01-2012 / Accepted: 21-05-2012
A study of burrying rice straws combined with two microbial product treatments (Bio-plant and Trichoderma) was conducted in spring rice and summer rice seasons on Red River alluvial soils of Ha Noi University of Agriculture. The experiments were arranged in randomized complete block design. Research results pointed out that rice straw burrying with and without microbial product treatment led to differences in growth and development of rice plants. Observations indicate statistically significant differences in leaf area index (LAI) and dry matter accumulation, yield components and grain yield. The use of Bio-plant product combined with rice straw burrying brought higher rice yield than Trichoderma product and control (without microbial treatment, with the summer crop yield of 40.5; 38.0 and 36.5 quintal ha-1, respectively. The treatment of rice straws with Bio-plant product gave higher income by VND 5.2 to 6.5 millions per crop hecta-1.
Risk and Risk Management Policy in Pig Production in Vietnam

Le Ngoc Huong, Nguyen Duy Linh

Received: 16-12-2011 / Accepted: 15-04-2012
Pig production industry in Vietnam current risks faced by pig producers are one of the main barriers to overall industry's development. Based on the survey results of current risk exposure in 1400 pig producing households in 7 provinces representing 7 ecological regions, the research shows that epidemic risks and market risks are the most serious risks faced by pig producers across all production scales. In addition, analysis of risk management policy in the industry also shows that of 62 legal documents, 53 documents are categorized as risk - prevention purpose, 04 documents categorized as risk - sharing purpose and 06 documents categorized as risk - coping purpose. However, this legal framework still exposes two major shortcomings: legal promulgation is slow and the framework is incomplete and not synchronized. Based on the analysis of risks exposure and current risk management policy, the research proposes recommendations towards improving risk management policy in pig production in two dimensions: i) In long term, the risk management system should aim at satisfying international standard (Codex); ii) In short term, legal documents need to focus on better risk management in epidemic prevention and treatment.
Introgression of Xa7 for Bacterial Blight Resistance to Restorer Linefor Development of Two-line Hybrid

Duong Duc Huy, Nguyen Van Hoan

Received: 07-09-2016 / Accepted: 16-12-2016
Two-line hybrid rice variety LC212 is valuable variety with high yielding potential, short growing duration, widely adaptation to environment but susceptible to Bacterial Leaf Blight (BLB). Backcross breeding method was conducted for transferring Xa7gene to restorer R212 which is male of hybrid rice variety LC212. The plants which have phenotype similar of R212, high resistance to three typical BLB races, carrying homogenous Xa7gene of BC2 and BC3 generation were selected by Pedigree selection. The selected plants were inoculated, similar phenotype was selected and MAS technicque were used to identify Xa7gene. The 25 lines R212BB of BC2F4 and the 8 lines R212BB of BC3F3 were selected. They are using for father step breeding of R212 restorer resistance to BLB as announced improved rice lines LC212.
Study on Some Biological and Pathological Features of Clonorchis sinensisInfection

Tran Van Quyen, Nguyen Van Tho, Nguyen Thi Hoang Yen, Nguyen Thi Hong Chien, Nguyen Van Phuong, Hoang Minh Duc

Received: 10-04-2012 / Accepted: 06-06-2012
Study was conducted by gathering natural ocurring snails, Bithynia spp., in Ha Noi, Hai Duong and Nam Dinh provinces. It was determined that Bithynia snail is the intermediate host of Clonorchis sinensis. Bithynia mainly occurs in calm water with the rate of 58.27%; The prevalence of Cercaria infection Clonorchis sinensis varied from 0.32 to 4.78%. Laboratory study showed that 100% snails float on the water surface in summer, 93.34% snails settle to mud; 100% snail lay eggs in summer and fall with hatching interval between 9 to 12 days. The study on micro-lesions of liver and bile ducts of cat infected by natural Clonorchis sinensis has shown that bile duct wall was thickened and fibrized, some ducts were obstructed with the hyperplasia. Inflamative cells of eosinophil, plasmocyte, lymphocyte and macrophage appeared around. Other symptoms include hepatic congestion, radial capillary expansion with infiltration of erythrocyte; central vein area of small lobe and interlobular vein expanded widely with infiltration of erythrocytes. Hepatocytes were found with fatty degeneration and vacuolar degeneration
Prevalence of Chicken Infectious Anemia Virus (CIAV) Circulating in Hanoi and Its Vicinity

Dao Doan Trang, Cao Thi Bich Phuong, Vu Thi Ngoc, Nguyen Van Giap, Huynh Thi My Le

Received: 08-11-2017 / Accepted: 20-03-2018
This paper reported the results of investigation on the prevalence of CIAV in Hanoi and its vicinity. By PCR method, the virus was detected in 92.86% of sampling farms and 50.81% of tested samples. The analyses of capsid protein coding gene revealed two genetic groups (group 2 and 3) of CIAV circulating in investigated areas. It was also demonstrated that all field strains of CIAV differed from the vaccine strains (Cux-1, P4 and 3711).
Food Hygiene and Safety in the Pork Delivery System in Lam Dong Province

Pham Thi Thanh Thao, Nguyen Xuan Trach, Pham Kim Dang

Received: 16-01-2018 / Accepted: 12-03-2018
The current situation of food hygiene and safety in fresh pork as well as the causes of microbial contamination at 31 traditional markets in three representative districts of Lam Dong Province (Bao Loc city, Lam Ha and Duc Trong districts)were investigatedthrough interviewingbutchersand sample tests. The resultsshowed that the contamination rate by E. coliin pork was found at 11.11% and 66.67% at the centralized and residential markets, respectively. The contaminationrate of Salmonellain pork collectedfrom residential marketswas 27.27%whileno Salmonellawas found in the samples fromthe centralized market. Coliformscontamination in water was found at 77.27% and 81.48% with both types of markets, respectively. Tools (knives and cutting boards) usedin the butcher shop didnot meet the requirements forsanitation in terms oftotal aerobic bacteria and Enterobacteriaceaein both types of markets. However, the residues of chloramphenicol, tylosin, tetracycline, clenbuterol, and salbutamol were not found in the pork sold at both types of markets.

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