Vol. 11 No. 3 (2013)

The study wasconducted attheDepartment ofPlantGeneticsandBreeding, Faculty of Agronomy, Hanoi University of Agricultural inthe springandharvestin 2012to assess thephotosynthetic capacityofthelinequality riceandfertilizerofthe relationship betweenphotosynthesisforriceyieldandquality. Experimental resultsshow thatthe intensity ofphotosynthesiscorrelatedwithSPADindexinthreestages:tillering(r=0,98), flowering(r=0,79) andninewax(r=0,97). The intensityof photosynthesisiscorrelatedwithindividualperformance(r=0,84) instageninewaxandnotcloselyrelatedindicatorsof quality.Fromthe experimental resultsT1, T3andT13line are thecurrentprospectsfor thebreedingof high quality rice.

Thestudy was conducted to establish the procedure for in vitropropagation of Morinda officianalisHow using stem segments. The stem segments were initiate cultured on MS medium containing 0,25 mg/l Kinetinand 1,0 mg/l BA, on which 96,6 % of explants induced shoots after 30 days of culture. The highest shoot multiplication rate (10,13 times) was obtained on MS medium supplemented with 3,0 mg/l BA; 0,2 mg/l IBA and 10,0 mg/l Riboflavin after 45 days of culture. Root induction medium was ½ MS containing 0,2 mg/l IBA and 0,4 g/l activated charcoal.The average rooting frequency was 100 % with a mean of 3.5 roots/shoot within 30 days. In vitroplantlets after 35-days period of rooting were the most appropriateforsuccessfulacclimatization in greenhouse. The highest frequency of acclimatized plantletswas 96,2 %inthe organic substrate containing 50 % of coconut fiber and 50 % of mushroom-production waste materials, the plantlets showed good growth and development.

The new E15Sline is thermosensitive genic male sterile line thatwas selected from 135S/Hoasuacrossingby pedigree method. The E15S has short growth duration, leaves numbers 14.1 and good phenotype such as: good tillering, stem and violet awn, long grain. The leaves and endosperm of E15S have aromatic smell mark 4. The critical sterility inducing point (CSIP) of E15S is 240C and high outcrossing ratio. The F1 was crossed between E15S and pollinators which have short growth duration, high yield, good quality and moderated resistance for disease and insects. The results of evaluation on F1 was selected E15S/Huongcom combination that has short growth duration (128 days), high yield (7.4 tons-1ha), milling rice 71.2%, head rice recovery 58.0%, long grain 7.1 mm and aromatic smell mark 3.8.

The pot experiment was conducted in net house to evaluate the effects of two salinity levels (NaCl 2‰ and 4‰) on the growth and yield of 6 local groundnut cultivars. The six groundnut cultivars are Sẻ Quảng Ngãi, Lạc, Lạc Quảng Trị, Mỏ két Tây Ninh, Giấy Tây Ninh, Đỏ Thái Bình. Results showed that salinity affected significantly growth and yield of groundnut. Increase in NaCl concentration decreased main stem height, dry matter weight, CO2 assimilation rate and triggered proline production in leaves of all cultivars. Besides, increase in level of salinity resulted in decrease of yield and yield components of groundnut. Among cultivars, Mo ket Tay Ninh obtained the highest pod yield at all salinity levels. In NaCl 4‰ treatment, the highest pod yield was found at Mỏ Két Tây Ninh (3.12g/plant), followed by Lạc Quảng Trị (3.04g/plant), Giấy Tây Ninh (3.03g/plant), Đỏ Thái Bình (2.79g/plant), Lạc (2.75g/plant) and Sẻ Quảng Ngãi (2.73g/plant), respectively. Among 6 varieties studied, Mo Ket Tay Ninh and Lac Quang Tri were believed to have good growth and yield performance and can be used as parental lines for salinity tolerance breeding in groundnut.

The aim of this study was to isolate and identify biochemichal characteristics of PCV2formpigs with PCVAD in 4 nothern provinces of Vietnam (Hanoi, Hoa Binh, Bac Giang and Hai Duong). Isolation of PCV2 would be a conclusive evidence to confirm the circulation of PCV2 and PCVAD in pigs of Vietnam. 8 of PCV2 were isolated from 38 samples collected from pigs with suspected PCVAD. PCV2 isolates were PCV2b genotype. The result of identification biochemical characteristics of isolated PCV2 shown that PCV2 could multiply in PK15 cell culture from the first or second passage, but no CPE was observed. TCID50of all ranging from 102,7to104,2 /ml.

The contribution of Eschrichia coli (E.coli) and Salmonella spp. to diarrhoea of pre- and post-weaning piglets was investigated in Son Tra industrial farm in Bac Ninh province. The isolation rates for E.coli from fecal samples of pre- and post-weaning diarrheic piglets were 86.2 and 78%, respectively. Serotype O149 comprised the highest percentage (48%) followed by O101 (20%); O64 (12%) and O8 (8%) in isolates from pre-weaning piglets. Among isolates from post-weaning piglets, O141 comprised 43.7%, followed by O139 (28.1%), O149 and O138 (9.3% for each serotype). Genes encoding for STa, STb, LT, F4, and F18 were detected at 32; 44; 24; 44 and 32% in isolates from pre-weaning whereas, from fecal samples of post-weaning piglets, the detection rates was 65.5; 21.8; 59.4; 0 and 34.3%, respectively. The virulence was found higher for isolates from pre-weaning piglets. Salmonella spp. were detected only from fecal samples of post-weaning piglets with lower incidence in comparasion to previous reports and all of the isolates were S.typhimurium with very high virulence. High susceptibility of both E.coli and Salmonella isolates to Apramycin, Cephalothin, Amikacin, Certiofur was observed. Taken together, E.coli seemed to play a dominant role in diarrhoea of pre-weaning piglets in an industrial farm and that can be shared by Salmonella spp. in post-weaning counterparts.

Formulated feed for rainbow trout at the beginning of growing phase from10g/fishto120g/fishwas conducted incoldwateraquaculture researchcenterin Sapa-Lao Cai. The experiment wasarrangedwithfivedifferentfeedincludingan imported feed from Finland andfourlocal formulated feed(TACB1, TACB2, TACB3, TACB4) containing46% proteinand18% lipid. Fishmealincorporationleveldecreased from62.27% to 52.75% andtheincorporationlevelofplant ingredientsincreases from14.66% to 38.4% in four local formulated feed. After75 daysofexperiment,resultsshowedthatthe growth performanceofrainbow troutarerelativelyhighintheexperimentalfeeds(from 1.43 to 1.47 g/fish/day), survivalrate high(98.0% -99.3%), lowfeedconversionratio(1.41 to 1.44). Therelative gutlength of fish wasproportional to theincorporationlevelofplant ingredients in experimental feed. The growth rate, feedconversionratioand survival rateof fish fed TACB3using56.12% fishmealand25.72% plant ingredientwere similar to fish fedFinlandfeed. The use of TACB3 can be reduce the production cost of 18% in comparison to imported feed, thus TACB3 can beusedasformulatedfeedforrainbowtrout at the beginning of growing phase.

Land Use Planning (LUP) is a potential solution for sustainable use of land in the long term by optimizing the effective use land resources. In addition, the vital role of Land Use Planning in socio-economic development needs to be analysed in a specific area. This is an important background task: In a transition country and emerging economy, such as Vietnam, it is a priori not clear, which force LUP actually exerts on actual development. Because of the high priority that the Vietnamese government places upon economic development, for example, it is conceivable that economic forces exert a much stronger influence that a plan. If there is strong indication that actual development is not correlated to plans, LUP was a lost cause from an economic point of view: More complex LUP would only generate more costs without possibly resulting in any positive change. If, in contrast, a strong influence can be documented, confidence in the entire LUP process would be strengthened.

In the study, random sampling method is used by selecting 90 households from three hamlets to analyze the efficiency of crops, cropping systems and some land use types (LUTs) in Nghi Truong commune. Currently, there are 5 LUTs and 15 land utilazation types. Fruit LUT has the lowest economic efficiency with a added value of 15.55 mil.VND per hectare which is only 0,08 times as high as that of Aquaculture LUT and 0,25 times as high as that of paddy rice–upland crops LUT. Aquaculture LUT has the highest economic efficiency with a added value of 188.95 mil. VND per hectare which is 8.5 times as high as that of paddy rice LUT and 3 times as high as that of paddy rice–upland crops LUT. Some land utilazation types which require high labor investment and added value are fish and watermelon - winter rice – vegetables. The ratio of N:P:K fertilizer used for crops was unbalanced compared to the standard. Most types of pesticides were used with excessive levels in comparison with the instructions on their packs.

This paperevaluate policy implementation experience of Payments forecosystemservices (PES) in the World andthe ability to applyinVietnam. Payments for ecosystem services is an economic tool regulating the relationship between service providers and beneficiaries from ecosystem services. Users of service have topay forthe participantsto maintain, protectand developthefunctionofecosystems.Themethodologyhasbeenapplied: methodinherited, gather informationthroughinformationseminars, gatheringdocumentation, analysis method, comparative, survey methodology, interviewing.Resultsofthis studyindicatedtheparticipantstopayforest ecosystemservices(sellers andbuyers), the govermentspecialrolein paying forpublic services(reforestation, mangroves ...) and coordinatingtheactivitiesof thePES. Manylegal documentsstatehasenactedasDecree99/2010/ND-CPand so on . The policies of payment for forest environmental services in 2011, 2012 brought 1,172.4 billion dong in state revenue.These are the initial results opening out development of PES in conserving and sustainably exploiting ecosystems in Viet nam.

The Research is based on the survey data in the area of 3 cities: Ha Noi, Da Nang, Ho Chi Minh and 4 provinces: Vinh Phuc, Quang Ninh, Long An, Binh Duong with 3 subjects: 1,445 households, 70 businesses using land and 224 local government officials in order to to assess the implementation of regulations on: change of land use purpose, land acquisition, compensation, support and resettlement. Research results are: (i) Regarding change of land use purpose: the majority of households and businesses say that the agreement mechanism should be applied; local officials support the coexistence of compulsory and voluntary mechanisms. (ii) Regarding land acquisition: most households say it has been carried out reasonably, in accordance with the order prescribed and ensuring transparency; businesses argue that there are still difficulties in accessing land due to many overlapping regulations. (iii) Regarding compensation: many comments suggest that land price frames are built and issued once in every 1-3 years; specific land price must be determined for compensation. (iv) Regarding support: new production land should be allocated, the level of support for livelihood and employment stability should be increased. (v) Regarding resettlement: the area of ​​resettlement apartments, land for service should be increased or land users whose lands are recovered should be given the priority of buying house or land in urban development project with preferential prices and tax exemption. The above-mentioned recommendations are basis to improve legislation in land acquisition, compensation and support for resettlement.

Control system automatic spray irrigation is an important factor, determines the success of the whole system in greenhouse vegetable production covered. Especially the vegetables in the nursery phase has many favorable characteristics for development of the disease, so the problem of monitoring and care of seedlings in the nursery should be top priority . The design, manufacture spray irrigation control system is very important in maintaining moisture, control the rate of the nutrients as well as the concentrations of plant protection spray vegetables. This paper introduces the results of research, design and manufacture of control systems automatic spray irrigation over time and temperature. Operator when the system is working just install the desired temperature value then the system will automatically control ventilation, misting pump to continuously ensure the installation parameters. The system also allows the operator can choose the location of fresh vegetables need watering time depending on the needs of each vegetable for systems with a variety of vegetables are grown in the same greenhouse.

This paper presents a model for tractor wheel worked on the agricultural condition. The model is developed on the base of Burckhardt model with interaction between tyre wheel and flexible base pavement. The mathematical model describes approximatively working characters of the farm tractor wheel, which can display general image for the ralation of kinetic and dynamic parameters such as motive force, driff angle, slip,…when farm tractor wheels move on the deformation ground. The boundary condition and the input parameters of the model can be defined from experimental studies.

Reduction gear housing of fork-lift truck is a machine part having complex structure. Thus, we cannot use available fixture during manufacturing process. Designing and manufacturing a specialized fixture is a requirement. In this study, it is aimed at designing specialized fixture based on drawing of gear housing; its technical and technological requirements and designing manufacturing process this fixture. The designed fixture has main parts is bearing plate, two bolster plates, collet chuck. The manufacturing process includes manufacturing bearing plate, bolster plates and collet chuck, thermal treatment, checking process and assembly. Checking and using test results show that designed fixture is reasonable and manufacturing process reaches technical requirements.

The chemical composition of the four raw material types of Trung du tea variety has been identified (a bud and three leaves, B type, C type and the old tea leaves). The results indicate that the moisture content, soluble substance, total catechin content, cafein and total polyphenol content significantly change according to the material quality. The younger the material is, the higher the levels of these components are, and vice versa. In the researched materials, the total polyphenol content ranges from 13,23% dry matter (DM) to 21,73%DM, cafein content ranges from 2,06%DM to 4,68%DM, the total catechin content ranges from 10,80%DM to 15,93%DM. In the catechins, the relationship of the content among them are as follows: EGCG>EGC>ECG>EC>C. EGCG and ECG content increase from the old leaves to the bud and three leaves. In contract, EGC content reduce from the old leaves to the bud and three leaves.

Six edible plants in Vietnam were selected to investigate antioxidant and polyphenoloxidase inhibitory activity, including Camelliasinensis, Piper betle, Psidium guajava, Ipomoea batatas, Piper lolot, and Morinda citrifolia L.. Antioxidative activities were evaluated by DPPH free radical scavenging capacity, reducing power capacity and inhibitory of lipid oxidation in oil-in-water model. In addition, polyphenol content of six edible plants were also determined. Research results indicated that all of plants had antioxidative activity via antioxidant tests and its antioxidant ability depended on species. Polyphenol contents were different from species to species. Their values varied from 11.73 to 188.19 mg GAE/g db. Polyphenoloxidase (PPO) inhibitory activity differed with species. Psidium guajava leaf had the highest activity of PPO inhibitory (64.77%), followed by Piper betle leaf (61.66%), Camelliasinensis leaf (43.87%), Piper lolot leaf (25.59%), Morinda citrifolia L. leaf (21.93%), and Ipomoea batatas leaf (21.42%).

This paper codifies theoretical and practical issues on sustainable development in agriculture. After discussing concepts, objectives and contents of sustainable agricultural development, the paper mentions to methodology for evaluation of sustainable agriculture. The paper also draws lessons learned from some of ASEAN countries for Cambodian agricultural development such as: Improving the socio-economic development policies, Improving the master plan and the detail plan for each region, Enhancing the quality of rural labor forces, Investing the rural infrastructure, Raising the farmers’ awareness in environmental protection.

Demand for pork consumption is highly fluctuated and depended on many factors. Thus, the estimation and analysis of factors affecting pork demand would contribute to stabilize the market for pork in particular and the whole market for consumption goods. The study used econometrics model and ANOVA analysis to analyze key factors affecting the demand for pork consumption in Vinh city, Nghe An province. Results showed that key factors such as price of pork meat, fish, and chicken, as well as real income of household have affected to the demand for pork consumption. On the other hand, some factors such as price of beef, personal background of consumers (like source of income, age, gender, and current living place of household) do not have any effect on the demand (of pork). In order to stabilize the market for pork, some measures are required such as controlling the supply of pork meat, developing the retail system (for pork), and planning for pig production in associated with poultry and fish production.

This paper employs Gravity model, first used by Tinbergen (1962), and a panel data of country pairs between Vietnam and her 18 major/stable trading partners in the period from 1995 to 2011. This is for the purpose to assess the impact of the “index of similarity in GDP size” (SIMSIZE in short) on imports and exports of Vietnam. The empirical results show that the index of similarity in GDP size promotes strongly Vietnam’s exports. By contrast, there is no evidence that demonstrates convincingly that this index induces the country’s imports. These investigations can somewhat contribute to the existing literature on the “New Trade Theory”, which was initiated in the late 1970s and in the early 1980s, in terms of testable implications from gravity models that emphasize in the case study between some developing countries.JEL Classifications: F13, F14, F15