The study mentions four obstacles catfish pisciculturists in the Mekong Delta include catfish product not to make the right market demand, catfish distribution style not to make the right choice, place not to make the right to sell and the time not to make the right choice. The study realizes that the factors such as scale, ability, income, total costs, quality of catfish product includes breeding catfish, foods and cures for catfish, experiences and methods of aquaculture which are the important factors affected to the process of catfish produced in the Mekong Delta and large scale, strong financial resources are less hindrance than small scale, weak finance. This study proposes five main solution groups to develop the Mekong Delta catfish pisciculturists market includes Control of input quality of catfish; Cooperate with some channels of purchase proactively; Define the catfish price swing cycle, supply according to the catfish market needs; many marketing forms with technological tools, penetrate the local market; the Government must enforce the plan and area management policy appropriately. 

?Sim? wine is a specialty of Phu Quoc with technological processes have been applied in production. Flavor and taste of fermented wine was good, but natural color (purple) of the product was still altered after fermentation. On that basis, survey of the influence of chemical (tannin, citric acid, vitamin C, rutine-vitamin C) (concentrations varies from 0.1 to 0.3%) and biological agents (pectinase enzyme) (concentrations varies from 0.1  to 0.6%) to maintain the color and to increase the wine transparency was of particular interest in this study. Results showed that tannin (0.2%) proved to be better than the other substances. This concentration of tannin not only maintains a durable and beautiful purple red but also increases the flavor characteristics of wine. The process can achieve high efficiency with the use of pectinase enzyme concentration 0.2-0.3%.

Black tiger shrimp (Penaeus monodon) has been farmed in a wide range of salinity but the animal may grow differently in relation with salinity. The objective of the research was to find out the effects of salinity on feed utilization and basic oxygen consumption of black tiger shrimp. The experiments were conducted with shrimp juvenile (10±2 g) at four salinity levels including 3, 15, 25 and 35?. Feed consumption and gastric digestion periods were conducted in the plastic tanks of 1 m3 in volume. Ten stomaches of shrimp in each salinity level were collected after feeding 20 and 40 minutes and 1, 2, 3, 4 and 5 hrs. in order to identify feed amount in stomach and feed gastric digestion. The apparent digestibility coefficients of feed, protein and energy of shrimp were identified by Cr2O3 marked feed method and conducted randomly in composite tanks of 0.5 m3 each with three replicates for each the salinity. Basic oxygen consumption was determined by respirometer, ten shrimps were measured separately at each of different salinities for 24 hours. The results of research showed that the black tiger shrimp juvenile was able to adjust the physiological responses to limit the loss of energy to adapt to low salinity. The daily feeding frequency should be increased as shrimp culture in the lower salinities.

The research was carried out in Thuan An village, Binh Minh district, Vinh Long province to assess of the present status of Watercress production, residuals of pesticides on soil, water and Watercress (Nasturtium officinale). Results of this research indicated that residuals of Cymethrin and Alphacymethrin on Watercress ranged from 0.01 - 0.05 and 0.23 - 0.99 mg/kg respectively. These residuals were in permitted ranges based on FAO?s standard, however, the stopping of pesticides before harvesting depends on market more than the safe level for consumers. The applied percentage of chemical fertilizer was double the organic fertilizer covering of 69 % and 31 % respectively. The profit of watercress depends not only on the yield but also on the market. Thus households should increase the amount of organic fertilizers, apply recommended pesticides to save costs, and develop the clean production for the consumer?s health.

The experiment was conducted at the Department of plant protection, Faculty of Agronomy and Applied Biology, Can Tho University from May 2006 to July 2007, at 28-300C and 75-85% RH, to observe the biology of Chilocorus politus Mulsant. Pupa of C. politus were collected from the predator generation that formely feeding on Pulvinaria sp. infested on Jatropha pandurifolia. After emergence, adults were allowed to mate, layed eggs, and after hatched, the newly first instars of C. politus were then cultured on eggs of Pulvinaria sp. that collected from leaves of Jatropha pandurifolia. The larvae were allowed to grow and develop into adults. Results showed that: The average incubation period was 3,7±0,1 days  and the duration of life cycle was 22,4±0,9 days. The  pupal periods were 7,1±0,1 days. The mean longevity of male and female beetle were 80,6±8,3 and 45,0±8,3 respectively, the mean pre-oviposition period of the beetle  was 1,4±0,2 days. The female beetles laid an average of 183,5 eggs and the hatching  was 33,5%. Both adult and larva C. polites not only can attack on eggs of Pulvinaria sp. and Depranococcus chiton, but also attack on young larva (T2) of D. chiton.

This study aims to understand the correlation between plasma protein phosphate (PPP) concentration and maturation and spawning of the black tiger shrimp. The study was conducted with pond reared and wild caught shrimp of 190?210 g each. Shrimp were reared individually in 200-L tank with recirculating water. The PPP was recorded daily starting from eyestalk ablation day and for two spawning cycles. The relative fecundity of shrimp was also observed at each spawning. The results showed that the PPP concentration increased significantly in accordance with the ovary developmental stages (p

?Economic crisis? has been becoming a nightmare for most of people around the world. Current global reccession is considered as the most serious one from the Great Depression (1929 -1933); it alarms  the existence of the capitalism. Some bourgeois economists reported that the cause of the crisis was the deficiency of state management. Thus they strongly suggest that the government will take more intensive role in the economy in order to avoid the similar crisis in the future. But will the state prevent the economic circle even in case the economy has sufficient management? The answer is    not sure. In order to deeply understanding this crisis, the article will discuss some following issues: (1) analysing the causes and effects of current global economic downturn; (2) refering to Marx?s economic theories and pointing out the root of the crisis; (3) based  on Marxist theories, foreseeing  the future of the capitalism.

An on-farm trial was carried out to estimate the effect of pig crossbred and feed supplement on pig growth performance and benefit to the current farm condition. The 24 individual growing pigs with initial to final mean live weight of 60 ± 2.3 kg and 92 ± 5.6 kg were used. The trial was designed as a 2 x 2 factorial with two crossbred pig groups, included of DLY (Duroc x Landrace-Yorkshire) and DPLY (Pietrain-Duroc x Landrace-Yorkshire), and two kinds of commercial protein (Car: Cargill or Nur: Nurpak). Results on pig breeds showed that the ADG (g/pig/day) was 694 vs 747; FCR (2.87 vs 2.91) and bodily round index (BRI) was 88.6 vs 91.5 for the DLY and DPLY, respectively. The economic benefit was higher in DPLY than DLY 10 %. To the feed supplement, the ADG was 720 vs 739; FCR (2.95 vs 2.82); BRI ( 90.2 vs 89.9); and feed cost per kg weight gain (VND) was 17,500 và 16,800 for the Car and Nur, respectively. The feed economic income tended improved in Nur (21 %) in comparison with the Car.

Research on production of ?sim? syrup was made base on the survey of the impact of concentrations (0.6ữ1%) and hydrolysis time (1ữ7h) of the enzyme pectinase. Simultaneous selection of the formula of ?sim? syrup processing with factors change, such as water added (30ữ60%), sugar concentration (50ữ60oBrix), the concentration of acid (0.3ữ0.4%) and concentration of Carboxymethyl Cellulose (0.1ữ0.2%). In addition, to extending product storage ?sim? syrup, pasteurized process (with temperature changing from 80 to 90oC during 2 to 4 minutes) is also interested in the research. The results showed that 0.8% pectinase enzyme used for hydrolysis for 5 hours perform effectively extracted. With appropriate formula processing (50% water added, 55oBrix and 0.35% citric acid), ?sim? syrup can be produced having sour sweet harmony and specific characteristics (in term of taste and color). Products can maintain its quality longer when it is pasteurized at temperatures 85oC for 2 minutes.

A large number of seafish is not used effectively in Vietnam. Studying on surimi-based seafood processing plays an important role to sovle this problem. Firstly, to increase surimi seafood quality, the proportion of starch (5-20%), pork fat (5-15%) and ?gấc? content (2-10%) are studied. The secondly, heating temperature of surimi processing was controlled at 160oC during 2-5 mins. Diversification of surimi seafood products (deep-fried or steamed product) were also performed in this study. The results showed that adding starch of 10%, pork fat of 10% and ?gấc? content of 2% gave the best quality product (in term of texture and colour of finished product). The nutritional value and flavor of the products were maitained during frying at 160oC in 2 minutes. Surimi-based seafood product (fried crumb surimi, green rice flakes surimi and other type of surimi as fish sausage) had superior nutritional properties.

The study on morphological characteristics of grey eel catfish (Plotosus canius) was carried out from January to May, 2009 at three locations in Hau river including Vam Nao (An Giang), Thot Not (Can Tho city) and Tran De (Soc Trang). Specimens were collected from fishermen and local markets monthly. The samples were kept in cold condition and transported to the lab ofCollegeofAquacultureand Fisheries,CanthoUniversityfor analysis. The results revealed that the body of Plotosus canius is elongated. Head is broad, slightly depressed, and tail is lateral flat. Mouth is broad and eyes are small. Four pairs of barbels were also observesed. First dorsal fin has spine, the second fin confluents with caudal fin and anal fin. Ratios of eye diameter per standard length, distance between two eyes per standard length and head width per standard length increase in according with the increase of body weight. Mouth dimension and length interrelate closely, however, mouth dimension increases quicker. Dendrictic organ is behind anus that only seen on species belong to Plotosidae family. Plotosus canius is omnivorous because their mouth is broad with small, short and seeded- shape teeth, esophagus is large, stomach is large piped shape while gut is short piped shape. Relative length of the gut (RLG) is 1.08. The first gill arch is covered by 22 to 25 long, sharp rakers. Respiratory organs include gill and skin.

Learning by discovery was mentioned by famous educators such as J. Piaget (1896 ? 1980), J. Bruner (1915 - ?), H. Freudenthal (1905 ? 1990). Learning by discovery have appeared in our country for many years. A lot of Vietnamese teachers have used Learning by discovery in their instruction. In order to exchange experiences on teaching mathematics in high schools, we introduce three models for teaching mathematical concepts by discovery, which we (in Can Tho University) have used to guide students of mathematics education how to apply them in course ?Teaching Practice?. In each model, we show steps which teacher should follow, give comments and illustrations.

Total bacteria, Vibrio and density of some beneficial bacteria in intensive shrimp culture ponds were determined. Sampling and sample processing were followed by the methods described by Huy (2003) and Chinabut et al. (2003). The density of Nitrosomonas and Nitrobacter were determined by MPN (most probable number) method. The results showed that the density of the total bacteria in pond sediment fluctuated from 5.3x104CFU/g to 1.2x106 CFU/g. The total bacteria count in the pond water was always lower when compared to that of sediment which fluctuated from 2.9x102 to 3x104CFU/mL. Bacillus density did not change during sampling and slightly fluctuated from 4.3x104 to 7.9x105 CFU/g, covering 87.9% of total bacteria count. On the other hand, the density of group Nitrosomonas fluctuated from 7 to 2.6x103 cells/g and shared 40.7% of total bacteria count. Nitrobacter group could only be found at the fourth sampling, had the lowest total count when compared to other groups, fluctuated from 5.5 to 1.9x103 cells/g, and shared 28.3% of total bacteria count. However, Vibrio tended to increase during the entire production cycle.

The use of insecticide to kill unwanted animals in shrimp farming has been found in the Mekong delta, Viet Nam. This study aims to determine the toxicity of decis (deltamethrin active ingredient) on growth of black tiger shrimp  (8-10 g/ind.). Shrimp were collected from pond and acclimated gradually to the salinity of 25?. The determination of LC50 was conducted with six concentrations of deltamethrin varying 0,75 to 2 àg/L. The results showed that deltamethrin was very toxic to P. monodon with the LC50?96 hr. of 1,05 àg/L. The effects of deltamethrin at the concentration of 1 and 50%LC50-96 hr. on osmotic and ionic regulations were designed at salinity of 25? for 14 days. The concentrations of 0,01 and 0,52 àg/L deltamethrin did not affect the osmotic and Na+ and Cl? regulations but caused increase of K+ at the first 3 hrs. The concentrations of 1, 10 and 50% LC50-96 hr. at the salinity of 25? did not affect the growth, but caused increase of mortality and prolongation of molting cycle.

The quality of sugarcane can be easily changed after harvesting. Experiments was done to examine the influence of storage conditions to change the quality of sugarcane (weight loss, sugar content, total acid content) were planted in Long My district during 12 days storage after harvesting. Experimental results showed that (1) the reducing sugar content increased from (4.7±0.14)% to (9.1±0.24)%, (2) sucrose content decreased during storage. Sucrose content of samples stored in the sun, no ventilation, no covering reduced by 10%, while the sample was covered only lossed 0.5% sucrose content compared to the initial sample; (3) although the concentration of dry matter and sucrose content were reduced, commercial cane sugar (CCS) and total acid content is almost unchanged and (4) the weight loss of sugar cane was about 6ữ7.8%  after 8 days of storage. The weight loss of sugar cane was lowest when they was covered during storage, ventilated sugar cane has the highest weight loss. The weight loss and sucrose content was reduced by several reasons will lead to less income for growers and sugar mills for sugar production. Also, the postharvest losses of sugar cane also cause the shortage of supply for raw materials as sugar cane is now more severe.

The study analyzed production efficiency of poultry raising and its determinants in theMekongDelta. The research results showed that poultry farm archived high efficiency. The results high light the scale, method of rasing, kinds of poultry, training as the main causes of the difference in profit of breeding poultry to get meat. Meanwhile, the scale, training, epidemic, quarantine are main determinants of the difference in profit of breeding poultry to get eggs. The probit function showed that training, age, and capital strongly effect on the decision if the household increase the scale or not. Based on the findings this paper introduces some related solutions. Finally, the paper offers some suggestions for local administration and the government?s policies which aiming to develop the poultry activity and to control the avian flu.

Spotted scat (Scatophagus argus) is an indigenous species and distributes widely in mangrove areas of the Mekong River Delta, Viet Nam. This study is aimed to find out the correlation of ovarian development with gonadosomatic index (GSI), hepatosomatic index (HSI), erythrocyte number (RBC), leukocyte count (WBC), hemoglobin concentration (Hb) and plasma protein phosphate (PPP). The results showed that the GSI was highest (12.0%) at ovarian stage 5, which is significantly different if compared to those of other ovarian stages (p0.05). Finally, the plasma protein phosphate was increased from 1.26 àgALP/mg protein at ovarian stage 1 to 3.73 àg ALP/mg protein at ovarian stage 5; but no significant difference was found among ovarian stage 3, 4 and 5. This study showed that there is a correlation between ovarian development stage with GSI, HSI and plasma protein phosphate concentration.

The objectives of this study were to determine the inorganic N dosage, in combination with supplying organic fertilizer to improve the fruit yield of pineapple planted on severe acid sulfate soil (Hypo sali epiothi-Thionic Gleysols) at Hong Dan, Bac Lieu province. Experiment was executed on the treatments of different levels of inorganic nitrogen which were at 8, 10, 12 g.plant-1 in combination with 10 tons of sugarcane filter cake compost on the base of 5g P2O5 ,10 K2O.plant-1 and 1 ton of lime per hectare. Results showed that soil pH was increased from 3.5 to 3.9. Organic amendment in combination with 10g N led to the significant increase of the concentration of available nitrogen, labile organic nitrogen, available phosphorus, base saturation percentage, and to the reduction of aluminum toxicity (reduced from 92% to 66% of Al saturation percentage). The combination of 10t.ha-1 of organic manureand 10gN.plant-1 on the base of 5g P2O5, 10gK2O.plant-1 a ton of lime led to improve fruit yield significantly in comparison with supplying inorganic N.

Decomposed heterotrophic bacteria attached on Rhizophora apiculata leaves was investigated in range of salinities 5? and 25? with 3 levels of nitrogen concentration 0ppm, 5ppm, and 10ppm; and different leaf amounts of 0g/L, 10g/L and 30g/L in laboratory condition. The bacterial density was higher in decomposed leaves than incubated water. The number of bacteria was significant higher at the salinity of 5? than at the salinity of 25?. The highest bacteria number was recorded at the incubated leaves amount of 30g/L with the salinity of 5?. There was the correlation between attached bacteria and total nitrogen concentration in the incubated water. The bacterial population was abundant in number and diversified in metabolic ability. Bacteria attached on the decayed leaves increased their density considerably. The present study indicated that attached bacteria could be nutritious food source in the decomposed food web in the shrimp-mangrove system.

Technical and economic feasibility of integrated agriculture-aquaculture-forestry farming systems in the buffer zone of U Minh Thuong National Park was analysed. The analysis is of great importance to appropriate solutions for improving livelihoods of local people while safeguarding bio-diversity of the buffer zone and conserving the core area of the National Park. Results showed that productivity of fish of integrated agriculture-forestry-fishery farming system are about 105-137kg/ha/year. Economic return of integrated agriculture-forestry-fishery farming system is lower than that of system of rice shrimp. The profit of rice shrimp farming system and two rice-shrimp farming system in 2006 is 10.8 and 19.4 million dong/ha, respectively. Economic return of integrated farming-systems showed that maintain agriculture-forestry-fishing farming system only provide food and saving a little money for household in the buffer area. Assumptions balance economic return between rice-shrimp farming system and rice-fish farming system; Australian Melaleuca-fish farming system in order to analyze the economic return shows that rice-fish farming system; Australian Melaleuca-fish farming system can be a solution instead of developing rice-shrimp farming system. Maintaining ecology of  buffer area by integrated agriculture-forestry-fishery farming-system have to support policies for farmers who live in the buffer areas as capital, reduced tax of agriculture, cultivation techniques of rice-fish, Australian Melaleuca. Priority solutions other support for members of households live in the buffer area as Priority of education, health care to reduce the heavy financial to maintain integrated agriculture-forestry-fishery farming-system aimed to protect resources and ecological in core areas of U Minh Thuong National Park .

This study aims to determine appropriate stocking densities for the culture of grey mullet (Liza subviridis). The study was conducted at NamCan district ? Ca Mau province from February to May, 2009. The experiment was conducted in 1 m3-hapa with four treatments including 10, 20, 30 and 40 ind./m3, each treatment was replicated three times. All hapa were set in a pond of 1000m2. Hatchery-produced fingerlings (initial weight 2.12 g/fish) were used for the experiment. Fish were fed with commercial pellets containing 35% crude protein. After 60 days feeding, fish with stocking densities of 40 ind./m3 had the highest growth rate (128.3 mg/day) and then 30 ind./m3 (107.9 mg/day), which were significantly different from those in lower stocking densities (p0.05).

Water spinach (WS) yield and nutrients were estimated on 3 farms that WS was fertilized by pig manure compost and on 3 farms by using digester effluent. On each farm 120 m2 of land for growing and harvesting WS in 2 first cuttings. The WS fresh biomass yield was higher on pig compost than for biodigester effluent. The content (%) ofLys was 0.97 vs 0.89, Thr 1.09 vs 0.96 and Met 0.45  vs 0.57. There was higher level in total lipid (%) of linoleic acid (C18:2) (15.9 vs 14.1), but lower a-linolenic acid (C18:3= 42.7 vs 43.2) in WS cultivated by pig compost compared with biodigester. An on-farm trial was carried out using 36 Yorkshire-type pigs with initial mean live weight of 54 kg. The trial was designed as a randomized block with 6 households and 3 dietary treatments. The basal feed was based on rice-by products, a protein concentrate and included: catfish oil 5 % (CF5); water spinach 5 % (WS5) and catfish oil 5 % with water spinach 5% (CF5-WS5). The ADG and FCR were not affected by dietary treatment.

Before 1975 the map data sources of South ofVietnamwas made on INDIAN 1960 coordinate system. However, the VN 2000 coordinate system has become the official system since 2001, that lead to the need for transformation of reference system between these systems. This result presents and evaluates among two methods for converting the coordinates system from INDIAN 1960 to VN 2000 system. The first method bases on Molodensky formula to convert data from INDIAN 1960 to VN 2000 through WGS84. The second method uses MapInfo with a new declaring for VN 2000. Compare the results of two methods with the result of GEOTOOL (recommended by Ministry of Natural Resources and Environment) in converting from VN 2000 to WGS 84 to verify the reliability that showed the longitude deviation was 0,1m and 0,5m for two methods. The difference results converted of Molodensky formula with the results of GEOTOOL was 0.1m by x-coordinate and 1m by y-coordinate, while the differences when using MapInfo was 0.5 and 1m. The results coordinate converted from INDIAN 1960 to VN 2000 of both methods showed the x-coordinate deviation was 0.1 m and the y-coordinate deviation was 1m. Which shows the Molodensky method gives the higher accurate than MapInfo, but MapInfo software can convert many vector format maps. It is a good convenient            for users.

A pilot-scale trial on alternative culture of mud skipper in the shrimp ponds was conducted with 3 stocking densities including 40, 70 and 120 fish/m² in Bac Lieu province. Fish were fed commercial pellet (30-40% crude protein). After 4 months of culture, mean individual weight and survival of fish were in the ranges of 16.8-22.5 g/fish and 16.4-22.9%, respectively. Average fish yield increased with increasing stocking density ranging from 1963 to 3335 kg/ha, in which fish yield in the treatment of 40 fish/m² was significantly lower than that in two other densities (p0,05). Particularly, in the treatment of 120 fish/m² had smaller fish size and lower selling price, which in turn results in gross returns that are smaller than the total costs. Hence, this causes a negative net return (loss of VND 34,5 mil./ha). On the basis of fish weight and profit values in this study, it was concluded that the rotational cultivation of mud skipper in shrimp ponds at densities between 40 and 70 fish/m² which could be considered an optimum on the yield and economic efficiency, especially low investment and less risky.

This study was conducted in Soc Trang province from April 2008 to September 2009 in order to evaluate the technical and economic aspects of the semi-intensive (SISCS) and intensive shrimp culture systems (ISCS). Fifteen households of each farming system were selected for collecting data during culture period. In addition, three ponds of each system were also chosen for sampling and determining the input and output of nitrogen(N) and phosphorous (P). The results of the study  showed that average shrimp yield of the ISCS (7,067 kg/ha/crop) was significantly higher than that of the SISCS (2,927 kg/ha/crop) (p0.05). Net income of the ISCS (231 million VND/ha/crop) was higher than that of the SISCS (71.6 million VND/ha/crop) (p

We fix some wrong in the Article [9] and then use these results to extend integration by parts for unbounded plurisubharminic functions,  and  .

In rice cultivation, lodging is an important factor which can reduce yield, seed quality and cause problem for harvest. High amount of nitrogen increased internode elongation and caused lodging. In this study, the effects of prohexadione calcium on rice lodging at different levels of nitrogen were examined. Treated rice seedlings with 10g ai prohexadione calcium/ha, once at the sixty fifth day after sowing or twice at the fiftieth and sixty fifth day after sowing (applying 90, 120 and 150kg nitrogen/ha) tolerated lodging. Increase in lodging and do not increase in rice yield were also recognized when nitrogen was applied more than 90kg N/ha. Applying 90kg nitrogen and treating 10g ai prohexadione calcium/ha, once at the sixty fifth day after sowing or twice at the fiftieth and sixty fifth day after sowing reduced lodging and increased rice yield. The results also showed that prohexadione calcium inhibited gibberellin biosynthesis and decreased plant cells, internode length and rice plant height. These helped rice plant tolerate lodging.

The peat swamp Melaleuca forest at U Minh Ha National Park has a high biodiversity. Forestfire is a severe threat to the ecosystem. Evaluation of the present situation of the forest and establishment of a method for a fire hazard warning system combined with GIS tools can be a great support for restoration and protection of this natural resource. The method based on weather conditions showed that the fire risk reached level five during about 40 days by the end of the rainy season, which indicates an  extremely dangerous situation. A method relying on fuel moisture content resulted in a warning system for different micro-areas. In the original forest with a thick peat layer, the fire risk was the highest one compared to the other areas. An integrated method, i.e. the combination of the two methods mentioned above had the advantage of including air temperature, moisture and the amount of fuel materials as well as the flammability. This method was used to estimate the fire risk level at a certain location of the area. Forest fire risk warning zones was also delineated, using GIS tool, which assist the forest officiers in locating the priority zones for protecting and preventing forest fire.

Acid sulfate soils which has area 1,600,000 ha, occupying 40% of the MRD?s total areas, is concentrated in Plain of Reed, Long Xuyen quadrangle, Ca Mau peninsula and Depressed area of Hau river. Seventy nine soil profiles have been collected from the ASS in MD for studying soil morphology. Thickness of A horizon of Plain of Reed, Long Xuyen Quadrangle, Ca Mau Peninsula (20.1; 20.4 and 26.5 cm, respectively) were lesser than that of Depressed area of Hau river (33.4 cm). The depth of sulfuric horizon occurred within 46.8-57.8 cm. The depth of sulfidic material of Depressed area of Hau river occurence was shallowest (89cm) as compared to others. Color indices RF for the ASS in MD varied 0.14 to 7.83. However, this index in Plain of Reed (2.28) and Depressed area of Hau river (1.97) were highest because of highly oxidation in B horizon.

The research aimed to study how to developNamRoi Phu Huu Pomelo production in Hau Giang. Objectives of the study are (1) to evaluate the production efficiency and its determinant, (2) to analyze the marketing channel. This paper applied researches methods of descripmtive statistics, Discriminant function, Probit, marketing channels of pomelo in Hau Giang province ?Vietnam. The sample size of the researches was 239 households and 49 middlemen involving in the marketing channel in the following provinces Hau Giang, Can Tho, Vinh Long, Tien Giang andHo Chi Minh city. The main problems of pomelo farmer in Hau Giang was low price, lack of market information. Suggested solutions to increase pomelo production, consumption efficiency and competitive capacity are: (1) to enhance high-quality hybridization, (2) to enhance high-production and crop specialization, (3) increase domestic and export market, (4) to encourage foreign investment in food processing, (5) to connect production and consumption system, (6) and to apply modern  food processing technologies.

This study aims to evaluate the effects of different salinities on the growth and survival rates of Spotted scat fish (Scatophagus argus) in oder to contribute to aquaculture development in coastal area of theMekongDelta. The experiment was conducted with 7 treatments of different salinities of 0, 5, 10, 15, 20, 25 and 30? applying recirculating system. Hatchery produced fish fingerlings of 1.73 g (two-month old) were stocked at a density of 30 fish per 200-L plastic tank. The fish were fed daily with pellet feed of 35% protein. Rearing water were continuously aerated. Afer 3 months of culture, the fish from salinity of 5? grew fastest with final body weight of 11.63 g, daily weight gain of 0.14 g/day and specific growth rate of 1.48%/ day, which were significantly different from those in the other treatments (p

This study was conducted in Soc Trang province from March 2008 to September 2008 in order to evaluate technical and economic aspects of coastal aquaculture systems. The results of the study showed that the coastal aquaculture systems in Soc Trang were diversified more intensively and some new species were cultured. The stocking density of intensive, semi-intensive, improved extensive shrimp, rice-shrimp farming systems were 26.3; 15.0, 7.6 and 7.7 PL/m2,respectively. The average shrimp yield of those systems were 4,665; 2,739; 1,504 and 919 kg/ha/crop, respectively. Net income of intensive, semi-intensive, improved extensive shrimp, rice-shrimp farming systems were 183.1; 102.2; 50.4 and VND 28.6 million/ha/crop. Mud skeeper culture system had high stocking density of 94.00 fingerlings/m2, average yield of 11.303 kg/ha/crop and net income of VND 207.5 million /ha/crop than shrimp culture systems. And mud crab culture systems had 0.83 fingerlings/m2 of stocking density, 1,619 kg/ha/crop of average yield, 82.8 million VND/ha/crop.

Study examined the effects of pre-injection of hCG and artificial rain on the maturity and spawning of the eel was conducted in three months with four triplicated treatments including without artificial rain-without hormone pre-injection (KPM-KTD), without artificial rain-hormone pre-injection (KPM-TD), artificial rain-hormone pre-injection (PM-TD) and artificial rain-without hormone pre-injection (PM-KTD). The results showed that the gonad somatic index (GSI) of this species was the highest at (PM-TD). There was significantly different (p