Vol. 15 No. 11 (2017)

A study was conducted to characterize the variation in morphological and agronomical characteristics among 7 Ipomoeaaccessionsoriginated from Vietnam and China. Results from the study showed that the plants were diverse in stem color, leaf shape, leaf pubescence, leaf lobing patterns, calyx, stamen, ovary, corolla shape and color, fruit and seed. These can be used as useful parameters for species identification. The results showed that 7 Impomeaaccessions belonged to three distinct species: (1) Ipomoea nil(L.) Roth (IP1, IP3, IP5, IP6); (2)Ipomoea purpurea(L.) Roth (IP4, IP7); (3)Ipomoea indica(Burm.) Merr (IP2).In addition, 7 accessions were also recorded with variation in agronomical traits such as dry matter, SPAD index, yield and yield components. Highest 1000-seed weight was obtained in IP1 (46.66 g), followed by IP3 with 46.45 g and lowest in IP2 with 32.52 g. GB2 was the one with smallest seed size. A high variation in seed yield was also recorded among 7 Ipomoea accessions.Seed yield varied from 11.03 g plant-1in IP7 to 19.01 g plant-1in IP2.

The genetic diversity of 30 mungbean accessions based on quantitative traits including phenological and agronomical traits and SSR markers were asessed. In addition, 30 accessions were evaluated for agronomical characteristics in 2016 spring and summer seasons. Experimental design was a randomized complete block with 2 replications. Results showed that 30 mungbean accessions were grouped into 5 and 4 groups based on quantitative traits and SSR markers with coefficients of 0.06 -0.31 and 0.62 -0.91, respectively. Field evaluation showed that all accessions had short growth duration of 60 - 89 days. Five accessions, 4249, 4476, HMB0025, 12200 and 14041 are potential for mungbean improvement programs.

The effect of fertilizer level and plant densities on seed production of the parentl lines of VNUA69 maize hybrid was investigated. A field experiment was conducted to evaluate the effect five densities(57, 62, 67, 72 and 80 thousand plantsper ha) with three levels of nitrogen application (120 kg N, 130 kg N, and 140 kg N per ha at a constant basal fertilizer of 80 kg P2O5 and 70 kg K2O per ha) on growth, development and yield of parentallines of the hybrid varietyVNUA69. Fertilizer levelsand plant densities affected plant height, yield and yield components of parentallinesdifferently. The yield of maleline D4 was 26.4 quintals per ha in Autumn-Winter 2016 and 27.6 quintals per ha in Spring season 2017 and of female line D6 was 28.6 quintals per ha in Autumn-Winter season 2016and30.3 quintals per ha Spring season 2017. The obtained results showed that appropriate planting density for both maize lines was 6.7 thousand per ha with 140 kg N per ha,80 kg P2O5and 70 kg K2O per hahectar basis.

The study on co-culture of tilapia (Oreochromis niloticus) and red seaweed (Gracilariasp.) with different feeding rates was conducted consisting of 4 treatments with 3 replicates. Fish was mono-cultured and fed at libitumas a control.In other three treatments, fishwere co-cultured with red seaweed and fed at 75%, 50%and 25% feed ration of the control. The experimental fish with mean weight of 4.65-4.69g were stocked at density of 250fish/m3 and at salinity of 10ppt. After 56 days of culture, the survival of fish was not affected by the feeding regimes, ranging from 95% to 100%.The growth rates of fish fed 75% satiation were not significantlydifferent(p>0.05) compared to those inthe control. Proximate composition of fish fillet (moisture, protein and ash) was similar among treatments while lipid level in the control was significantly higher than the 50% and 25% satiation feeding regimes.These results indicated that tilapia- red seaweed co-culture with feeding75% feed rationof the controlstill sustained normal growth performance of tilapia and reducedthe feed cost as well as maintained better water quality.

This study compared several morphological characteristics and reproductive biology of two fresh-water snail species, Pila polita(Pp) and Pila gracilis(Pg). The colors of the snail shells change over the stages in their life. With shell height <25 mm, Pp and Pg show green-yellow and green-dark color, respectively; with shell hight larger than 25 mm, Pp shell is green-dark and Pg is brown-yellow. Pila politaand Pila gracilisshow a close correlation between morphological characteristics such as shell height with shell width, shell height with total weight or shell height with meat weight. Results of broodstock conditioning and observations of some reproductive biology characteristics of two species showed that the weight and diameter of snail eggs, shell height and weight of newly hatched snails from Pila politawere higher than those from Pila gracilis(p<0.05).

Circoviruses has been detected in diverse animal species, including sus scrofa. To date, only PCV2 is demonstrated as a causalagent of porcine circovirus associated diseases. In 2015, a novel circovirus (Porcine circovirus 3, PCV3) was detected for the first time from pigs suffered from porcine dermatitis and nephropathy syndrome and reproductive failure. Since then, PCV3 has been reported in several pig producing countries. This study was carriedout to investigate the presence and the prevalence of PCV3 in the pig populations in northern Vietnam. The PCR screening detected the presence of PCV3 in 6 out of 135 samples (4.44%) collected from7 Northern provinces in 2011 and 2016-2017and fivestrains were successfully sequenced. The capsid coding gene (ORF2) of 5 strains were 642 bases in length, containing39 point nucleotide mutations and 9 mutations were non-synonymous. The phylogenetic analysis on the basisof ORF2 gene suggested that 5 Vietnamese PCV3 strains belonged to PCV3bgenetic cluster, of which, 4 out of 5 strains were clustered closely with Chinese PCV3 strains.

Parasitic nematodesnot only cause disease ofmarine fishandreduce fish production but also spread to humansand cause disease. The results of research on fauna, biology, ecology of the parasitic nematodes in marine fishes are the premise for the prevention of parasitic nematode diseases in aquaculture and medicine. This paper was the first documented case of parasitic infection and composition of parasitic nematodes in some coastal marine fish of Quang Binh province. A total of 240 fish individuals of 40 species, 26 families, 8 orders collected from the coastal of Quang Binh province were examined for nematodes. Of these, 93 (38.75%) fish were infected with nematodes with the intensity ranged from 1 to 148 nematodes/ fish. Fifteen nematode species of 3 orders, 6 families, 11 genus were identified by morphology, adding 4 species to thefauna of Vietnam and six new fish host species of these nematode species..

Yellow flower Camellia spp. are multiple purposeplantsof high economic values. They areused as a nutritious beverage, medicine and ornamental plants.This paper reported theresults of the propagation of three yellow flower camellia species by cuttings. The cuttings were sterilized withBenlat 0.5% for about 15 minutesandthentreated with plant growth regulators for 5 minutesand the results were recorded after 80 daysof experiment. With C. tamdaoensis,cuttings treatment withABT at a concentration of 200 ppm, C. flava and C. chrysanthaof cuttings treatment withβ-indol butyric acid (IBA) at 100 ppm and 150 ppm hadthe survival rate of72.24 - 83.33%, the shootregeneration rate of 71.33 - 83.67%, root formation rate of71.67 - 80.33% and the rooting index of8.39 - 9.77. The apicaland middle cuttings reached the survival rate of 75.67 - 80.33%, the root formation rate of 73.67 - 77.33% and coefficient of root formation was 6.23 - 6.87. With the medium containinggarden soil, rice husks and sand at 2:1:1 ratio, the survival rate and root formation rate were at 78.67 - 87.79% and 72.33 - 76.32%, respectively. Reduction of light by50 % shading resulted inthe survival rate of 87.43- 93.33%. The cutting method wassuitable forpropagatingyellow flower Camelliasfor germplasm conservation and development.

Oyster mushroom (Pleurotus spp.) is a delicious edible fungus with high nutritional and medicinal values. Itcontains all essential amino acids and several polysaccharides.Five strains of oyster mushroom werecultivated on rice straw sterilized at 121oC for 100 min and on rice straw piled for6-7 days at 60-70oC. The results showed that of5 oyster mushroom strains, PN1 showed the highest growth rate. In addition, sterilized straw was the most suitable material for the growth of PN1 with bio-efficiency at 73.8%. For further investigation, PN1 was cultured on a mixture of different materials including straw and some agricultural wastes such as cotton seed hull, sawdust, husk, and rice bran. It showed that the mix(in percent) with straw (84), cotton seed hull (10), rice bran (5) and CaCO3(1)was the best medium for the mycelial growth and fruitingbody yield and the bio-efficiency of PN1reached 77.4%.

After the harvest, most by-products from rice straws, plant roots, and stems etc are burned by farmers. This activity causes environmental pollution. The use of variable source of agricultural by-products as feed for livestock is considered as one of the alternative reduce waste. Agricultural by products have high fiber content, low digestibility and energy value. This study aimrd to select lactic acid bacteria with biological characteristics such as high lactic acid production, production of some extracellular enzymes (amylase, cellulase, xylanase) and antibacterial activity against pathogenic bacteria for treatment of agricultural by-product as cattle feed. Results of this study showed that from 61 strains lactic bacteria isolated, 27 strains were selected with high lactic acid production (200-263ºT) and good growth at 37ºC. From 27 strains, 8 strains were identified with extracellular enzyme production of amylase, cellulase, and xylanase with ring diameter of substrate resolution of 7-33 mm. In addition, this study revealed 3 strains with antibacterial properties such as T6.2 strain against gram positive Listeria monocytogenesand two strains, C3.15 and C3.19, against gram-negative (E. coli). Three strains were capable of decomposing straws, but the C3.19 showed strongest decomposition.

Genetic variability of the initial materials is considered as the prequistie to generate the genetic variation for the selection process. Twenty-five gladiolus accessions were grown at Gia Lam-Ha Noi in 2015-2016 Winter-Spring season to study genetic variation of traits and direct and indirect attributes affecting flower quality for selection of parents for breeding. The experiment was designed in a randomized complete block design (RCBD) with three replications. Analysis of genetic divergence using morphological characters devided the gladiolus accessions into 4 groups, of which 13 genotypes of groups II and III showed high flower quality without leaf scorch symptoms. All traits had high heritability (79.6-99.7%) and the expected genetic advance varied from 0.38 to 66.53%. Leaf length, diameter of spike can be improved by cultivation practices. Length of leaf and leaf numbers were positively correlated with the length and diameter of the spike.

The exploratory factor analysis (EFA) method was usedto assess the level of importanceof impact factors(IFs) affectingdecision making of households to participate in HGP. The research results revealedsix key impact factors: (1) Financial economic efficiency of plantation; (2) external support ; (3) wood market; (4) forestry policies; (5) awareness of local authority; and (6) Internal mechanism of HPG. Based on this analysis, the study proposed six solutions to promote and develop HPG: (1) improvingthe financial efficiency of plantation; (2) promotingthe external support, developingHPG and gradually improvingtheir autonomous capacityof certified plantations; (3) market development in the value chain of wood products with sustainable forest management certificate; (4) revising current gaps of forest policy for plantation forest development; (5) enhancingthe role and capacity of local authority to implement the policy; and (6) Improvingand developinginternal mechanism of HPG

One of the causes of unsustainable poverty reduction is the capability of staff and agencies that implement poverty reduction policies. Capability to implement poverty reduction policies is the ability to successfully realize the goals of poverty reduction policy. Capability to implement poverty reduction policies is focused on three factors: knowledge, skills and attitudes of staff in the policy implementation process from planning, propaganda, coordination, continuation, adjustment and monitoring the implementation of poverty reduction policies. Based on different perspectives and approaches, the paper conceptualizes the theoretical and practical issues of the capability to implement poverty reduction policies and establishes a solid scientific basis for research on enhancing capability to implement poverty reduction policies, which contributes to improved enforcement effectiveness and poverty reduction impacts of policies.