Vol. 14 No. 9 (2016)

TBR225 rice variety wasselected from K2/TBR27 cross since 2006 Autumn cropping season. The parentalvarieties K2 and TBR27 were selected from working collection of Thaibinh Seed introducedfrom China. Pedigree selection was made continuously from F2 to F5 and perspective uniform line was named NC7. NC7 line possessedvarious valuable characters such as short growing duration, good plant type, high disease resistance, high yielding potential, long grainwith whiteness and translucence, low amylose content, andgood taste quality. After a series of replicated yield trials at thebreeding nursery of Thaibinh Seed, NC7 proved to be promising line and was named TBR225. TBR225 was evaluated/tested forDUS and VCU test by National Center for Plant Products and Fertilizers inorthern and central regions of Vietnam since 2012 Autumn season. The average grain yield of TBR225 ranged from 6.5 to 7.5 tons/ha, 3.76 - 11.44% higher than the check variety,KD18 and 4.87 - 15.67% higher than Huong thom1.TBR225 was prelimarily approved for production trial according to the DecisionNo.458/QĐ-TT-CLT datedNovember 08, 2013 and officially recognized as ntional variety according to the Decision No.202/QĐ-TT-CLT dated June 09, 2015.

Random Amplified Polymorphic DNA (RAPD) markers were used to characterize the genetic diversity and relationships among 53 accessions ofAcacia crassicarpa. A total of 56 markers were tested. The results indicated that 16 markers produced 142 allelesin which 131 were polymorphic (accounting for 92%) and of which 12 generated 100% polymorphic alleles with the sizeranging from250bpto3000bp. Based on the genetic similarity of 53 accessions, two main clusters with the similarity index ranging from 0.47 -0.99 were grouped by NTSYSpc2.10 software. Cluster I included nine accessions,namely A.cr.S.6, A.cr.N.34, A.cr.S.38,A.cr.S.51, A.cr.N.81, A.cr.N.84, A.cr.N.86,A.cr.N.87and A.Cr.N.147. Cluster II was composed of 44 remaining accessionswhich were divided into 3 sub-groups of level 1 (IIa, IIb and IIc). High level of polymorphism among Acacia accessionssuggested that RAPD markers can be useful for A.crassicarpa germplasmcharacterization and conservationand efficient selection of for drought tolerance.

This study was conducted to evaluate the combining ability of thinner pericarp waxy maize inbred on the eating and nutrient quality traitssuchas tenderness,sweetnessandamylose contentthrough diallel cross using method 4 of Griffing. Six waxy maize inbred lines and their crosses were evaluated in a complete block design with 2 replicationswithplot size of14m2andHN88as thehybrid varietycheck. Results showed that six parental lines and the crosses had short growth duration. Thegrain yield of parental linesranged from 24.48 to 29,61 quintal/haandfresh ear yield of the crosses was higher than the check variety. Four waxy maize inbredlines,D1, D2, D5, and D6 had high values for general combining ability on the fresh ear yield,thinner pericarp trait, protein, amylosecontentand other traits. Our results suggest that development of hybrid waxy maize variety for high quality should focus on parentalinbredlines withcombining ability forthequality traits.

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.

The experiment on influences of different foods on the life cycle and the intrinsic rates of natural increase of the predatory mite Neoseiulus longispinosusEvans was conducted at the laboratory of the Center for Citrus Research and Development, Chuong My district, Hanoi city. The natural foods were sixcommon phytophagous mite species on bean,teaand citruses. They weretwo spotted spider mite,Tetranychus urticae;carmine spider mite,Tetranychuscinnabarinus;red spider mite on tea,Oligonychus coffeae;Citrus spider mite,Panonychus citri;Scarlet mite Brevipalpus sp.,and citrus rust mite,Phyllocoptruta oleivora. The factitiousfoods were twostored product mites: Carpoglyphus lactisand Tyrophagus putrescentiaeand pollen of Typha latifolia.The results showed that, at 27.5±1oC, 80±5% RH, the predatory mite N. longispinosusdeveloped well on thenatural foods, meanwhile the life cycle of the predatory mite was not completed on twostored product mites species and on the pollen, they only developed to the protonymphstage. The life cycle of the predatory mite N. longispinosusrearing on T. urticae, T. cinnabarinus, P. citri, O. coffeae, Brevipalpus sp., and P.oleivora was 6.65 days, 6.56 days, 6,59 days, 7.41 days,. 7.47 daysand 7.26 days, respectively. Correspondingly, the intrinsic rate of natural increase (rm) of the predatory mite was0.2997, 0.2966 and 0.2980 when reared on T. urticae,T. cinnabarinusandP. citri, respectively, significantly higher than rearing on O. coffeae(0.244), Brevipalpus sp.(0.199)and P. oleivora(0.239).

This study identified the ITS (Internal Transcribed Spacer) sequence of 11 groundnut late leaf spot fungal isolates collected from Vietnam, mainly from Nghe An province in 2013. The ITS sequences of the 11 isolates were identical among them and highly identical (99.7 and 100%) with two available isolates of Mycosphaerella berkeleyi onthe GenBank. Rep-PCR technique (Repetitive sequence primed PCR) with 3 sets of primers designed on the repetitive sequences of bacterial genome including the repetitive extragenic palindromic (REP) sequence, enterobacterial repetitive intergenic consensus (ERIC) and BOX element, was used to investigate the genetic diversity of 33 M. berkeleyi isolates.PCR using BOX primers (BOX-PCR) produced polymorphic bands from tested fungal isolates. Rep-PCR analysis proved that fungal populations in Nghe An were of low genetic diversity. There was no correlation between Rep-PCR defined fugal groups with the origin of the isolates (location of sampling, groundnut cultivars) and morphological characteristics of the isolates (color and size of cultures)

Thisresearch was carried out to evaluate drought tolerance of 32 varieties of native cucumber in Vietnam. The seedlings were grown in pots containing 5 kg of mixture (soil + coconut fiber, ratio 1: 2) with basal fertilizerof CaO:N:P2O5: K2O with: 10: 2: 2: 1.5g, respectively, per pot. All pots were placed in a nethouse. The moisture of the pots were maintained at 80-85% of saturation at all time except at stress stage. In stress-treatment, watering of 2-expanded-leaf seedlings were withheld10 days, then watered again. The results showed that, drought reduced leaf number, leaf area, plant height, and shoot diameter in most non-tolerantvarieties ( low DRI). The drought-tolerant varieties (DRI> 1), had a slight reduction of leaf number but had a strong reduction of leaf area, that might help reduceevaporation. In these varieties, however,there was onlya slight reduction of shoot diameter that might notlimitwater-transportation. The result also showed that 13 varieties had good drought tolerance, which could be used as the materialsfor breeding of droughtresistance.

Maceration extraction of Caesalpinia sappan L. (CS) in ethanol solvent (96%) followedby steam distillation at 80-90oC resulted in an average extract efficacy of 6.80%. Ten percent extract sollution showed inhibitory effects on E. coli. The effectswere concentration-dependent and higher on standard E. colistrain in comparison to those on chicken-derived isolates. The strain dependent inhibition was similarly observed for doxycycline, ciprofloxacin and colistin. The 10% sollution of CS extract exerted preventiveand treatment effects on experimental infection with E. coliin Yellow-featherchickens. The results can be considered asscientific basisfor further studies on prevention and treatment potentialof CS extracts.

The aim of this study was to evaluate the quality and the microbial population of king grass (Pennisetum purpureophoides) silage. The experiment was carried out in a completely randomized design consisting of four treatments with three replications, namely control: traditional king grass silage without additive as a control; CT1: king grass silage with 5% salt; CT2: king grass silage with 5% molasses and CT4: king grass silage with 5% salt and 5% molasses. All silages were prepared using plastic jars (5kg) and incubated at room temperature (25 - 30oC) for 90 days. Silages were analyzed for fermentation characteristics and microbial diversity. The result confirmed that king grass ensilaged with molasses (CT2, CT3) had good fermentation characteristics compared with control and CT1 group. The silage (CT2 & CT3) showed golden yellow color, pleasant and acidic smell, no viscosity, and no mold growth with pH value below 4,2 (3.98 - 4.18). DM and crude protein were reduced by 1.15 % and 0.35% respectively. The highest content of lactic acid (1.30 - 1.58%) and the lowest ratio of ammonia nitrogen to the total nitrogen (5.11 -7.03%) were observed in CT2 and CT3. The microbial diversity in silages indicated that there was a highest population of lactic acid bacteria in CT2 and CT3 (194.17x106 - 316.33x106 CFU/g). The number of Bacillus sp. and Clostridium sp. mold and yeast were highest in control and CT1 (P < 0,05).

In Marc-145monolayer cells, PRRS virus causedcytopathogenic effect (CPE) as early as 36 hourspost inoculation(35%) and reached100% at 60hourspost inoculation. The titer of HUA-PRRS01 virus was3.16x105(TCID50/25µl). Experimental pigs had normal body temperature andshowed nounusual reactions after injecting with inactivated antigen thatwasproduced from HUA-PRRS01 virusstrain. Inactivated HUA-PRRS01virus was able stimulate experimental pigs to produce specific antibody ofPRRSV with high antibody level. Theyhad antibody levelover S/P ratio (0.4)at 14 dpi (averageS/P ratiowas 0.697 ± 0.271), reached a maximum at 42 dpi (averageS/Pratiowas1,197 ± 0,256), and then decreasedat 49 dpi with antibody levelremainingover S/P ratioof 0.4. In the present research, antigenic characteristicsof HUA-PRRS01 strain virus was testedin pigs. These results are useful for selecting thevirus strain for producing PRRS vaccine to minimizeeconomical loss caused by PRRSV.

The present study aimed to investigate the bacterial flora in the vaginal discharge of dairy cows and their susceptibility to various commonly used antibiotics. Overall, 54 samples from cows with or without post-partum metritis were used for bacterial isolation and identification usingstandard bacteriological criteria. Results showed that bacterial density in the vaginal discharge of cows with postpartum metritis was significantly higher (P<0,0001)than that of cows without postpartum metritis. Two bacteria genera were isolated from both uninfected and infected cows, i.e., Staphylococcus spp.and Streptococcus spp.Their prevalence in the vaginal discharge of uninfected cows was 20,00% and 13,13%, respectively. Meanwhile, these two bacterialgenera were detected from all the samples (100%) of infected cows. Antibiogram demonstrated that these two bacterialgenera were highly susceptible to four types of antibiotics including norfloxacin, amoxicillin, tetracycline and kanamycin. The results suggested that these four kinds of antibiotics could be used for the treatment of metritis in dairy cows.

Infectious bronchitis (IB) is one of the severe infectious disease causing tremendous economic losses in the poultry industry. In order to have an effective strategy for disease prevention and control, a method for rapid and accurate dectection of infectious bronchitis virus (IBV) is urgently needed. In this study, the tissue samples oflung, trachea and kidney collected from IB-suspected laying hens in three hen farms in Hanoi (Ba Vi District), Thai Nguyen and Bac Ninh have been diagnosed by the RT-PCR method. The diagnostic results showed that 34/71 (47,88%) samples were positive with the IBV.The common clinical signs ofIBV-infected hens included fever, depression, loss ofappetite,dyspnea, coughing, sneezing, tracheal rales, nasal discharge, diarrhea, fluid retention in the abdomen, facial swelling and conjunctivitis. The pathological signs in IBV-infected hensincluded kidney swelling (90%), tracheal hemorrhagea (77.5%), pulmonary hemorrhage and congestion(63,7%), inflammation of airsacculitis (60%) and upper respiratory tract (57,5%). Egg production and quality in IBV-infected laying hensdecreased by 20,7to 43%.

The mixture of Green Malachite (MG) and formalin is the most effective chemical used to treat Ichthyophthirius multifiliis and other prasites infecting fish.However, MG was prohibited to usein aquaculture due to its potential risks to the environment, animal and human health. The prohibited use of MG has caused many difficulties to treat this parasite and other aquatic diseases. This study was conducted to examine a new, environmental friendly, safe and effectively method alternative to MG. Formalin 25 ppm (F25) was combined with a high oxidizing PHA (15% peracetic acid, 25% hydrogen peroxideand 25% acetic acid) at different concentrations of 1, 3, 5, 7, 10 ppm (PHA1, PHA3, PHA5, PHA7, PHA10) and the mixture was used to experimentally treat theronts (in vitro), and mature Ichthyophthirius multifiliis (trophonts) parasitized on Grass carp (in vivo), following with comparison to mixture of Green malachite and formalin (F25 + G0.25). The in vitrotest results show that the mixtureof F25 + PHA10 could kill 96.5% theronts within 48h. For in vivotest, treatments were conducted 72h post infection. After 10 days of experimental treatment, the control group (infected without treatment) had a high mortality rate (85.56%).In contrast, the F25 + G0.25 showed high efficiency in controlling this parasite with 94.43% fish survival. The mixtures F + PHA were effective to mitigate mortality rate compared to the control group, in which the mixture of F25 + PHA10 resulted in highest survival rate (92.23%), following with low prevalence and infection intensity, 5.13 and 1.81 parasites/sample at 40 x magnification, respectively. In addition, Ichthyophthirius multifiliis exhibited changes in morphology and moving behaviour. Results of following 10 days post treatment showed that fish treated with F25 + PHA10 recoveredeffectively, stopped mortality and probably created immunity against this parasite.

Agricultural land use playsavital role in producing agricultural products andagricultural commodityproducts. Recently, some models of agriculturalland use in Luong Tai District haveactually been set up to produce more commodity goods. The research objectivewas to assess the efficiency and commodity productivelevel ofthe agricultural production land use modelsin the district. The results show that there were three land use types (LUT) with 15 sub-LUTs. Some agriculturalland use models were assessed withhigh level of efficiency and commodity production, such as vegetable crops, galangal (Alpinia officinarum) and carrots. Therefore, agricultural land use models forcommodity production contribute significantly toagricultural development towards to increasing gross output and added value.

Metal forming is a basic mechanical industry. It allows the manufacturingproducts with complex shapes and size.Hydroforming process is a special drawing method. In the last years, this method is often used for forming of thin products with complicated geometry in the airplane and automotive manufature, because it hasmany advantages compared with conventional deep drawing process. Nevertheless, at present in Vietnam the hydroforming design islargelybased on the experience.In this paper, the author apply software Eta/Dynaform for simulation ò the hydroforming process of thin product to optimeze the deep drawing hydroforming process.

Water-pine shoots (Glyptostrobus pensilis) derived fromin invitroculture of 8mm in sizewere grafted(whip grafting) onepicotylsof 30 day-oldChinese Fir(Cunninghamia lanceolata) plantlets. The Chinese firindividuals were produced by sowing seedson basalt and coconut fibermix with 7:3 ratioand 70%moisture The mix wasautoclaved at 1210C, 1 atm for 2 hours to sterilize. This grafting method producedcomplete invitrografted plants. They survived and grew well after transplanting tothe naturalconditions. The resultsmight contribute to research forconservation of a rare and endangered water-pinespecies.

Expanding the market share of organic foods faces many difficulties in developing countries like Vietnam. One of the most important reasons is inadequate perception of organic foods due to limited information. The study examined Vietnamese consumers’ perception, and identified factors affecting the awareness of organic foods in the country. We interviewed 203 consumers randomly chosen at big supermarkets in Hanoi city. Through using descriptive statistics and applying ordered logit model, our study showed that only about 10% of the consumers had adequate awareness of organic food, while a half only heard of it but did not understand about organic term. Forty percent of remaining people have never heard of organic foods. Specific factors affecting the Vietnamese consumers’’ perception of organic foodare the product origin/label, food safetyevaluation and consumers’, education, age and occupatio.

The manufacture of export joineries of traditional carpentry villages in the Red River Delta (RRD) region has attained substantial achievements in the recent time with a fast increase in wood processing bases that offer jobs and bring about positive significance in terms of socio-economic efficiency for the region. Beside the attained achievements, there still exist short-comings that need to be overcome, such as the limitation in export market for handicraft joineries, lack of stability and sustainability, especially the very limited exportation to potential markets such as EU, the U.S and Japan. Based on database study, interview method, group discussion, descriptive statistics and analytical statistics, this article focused on analysis and evaluation to clarify the current state of joinery manufacturing in some carpentry villages in the RDR, from which solutions to promote the production of these handicraft villages are proposed.

This study aimedto investigate thesocio-economic status offarm households growing star-apple “Lo Ren”according to Global GAP standard and clarifythe reasons for GAP adoption and abandonment after obtainingGlobal GAP standardcertification. A total of 54 star-apple growers who appliedGAP and 53 independent growers residing in Chau Thanh district of Tien Giang province were selected for primary data collection. Descriptive statitics and T-Test methods were employed to analyze the collected data related to GAP adoption and abandonment. Regardless of the benefits of GAP practices, such as reduced fertilizer and pesticide application and safety for environment, the abandon of GAP star apple growing was attributed to the uncertainty of market and unstable selling prices. Thus, only those farmers with higher education level, better economic condition and highexpectation for higher selling price of GAP-certified product engagedin growing star apple using GAP..

Although business management (BM) is still one of the sectors with high demand and relatively large employment opportunities, the workforce for BMis still failing to meet the needs ofqualified skills. This article studiedworkingcapacity of graduatesfromBM, Vietnam National Universityof Agriculture (VNUA) who are working at theenterprises in Hanoi and proposed some suggestions to improve the workingcapacity for graduatesto better meet the requirements of busines. Research showedthat the working capacity of the graduatesfromBM ofVNUA wasevaluated at moderate levelformost evaluation criteria. Compared to other universities, the communication skills,the creativenessin handling the situation, and the ability in organizing socialactivitiesof graduates fromVNUAwerelowerwhile practical skills, the spirit of learning and adaptability were considered to be better. To enhance the working capacity forstudentsin BM atVNUA, the following considerations are proposed: enhancingthe understanding and application of knowledge into practice for students, improvingforeign languagefor better communication, increasingactiveness through social activities, youth and students association, and offering boreexchange opportunities to shapesocial skillsforstudents.