Vol. 20 No. 11 (2022)

The experiments were conducted to evaluate the growth, yield and grain quality of some quality rice varieties in the autumn season 2019 and the spring season 2020 in Dong Hai, Quynh Phu, Thai Binh. The experiments were arranged in a Randomized Complete Block Design (RCBD) with three replications. Six quality rice varieties (VR3, VR4, VT18, HN01, ĐHS15, Thai Thinh) and the control variety Bac Thom 7 (BT7) were evaluated. The results showed that all of rice varieties were early maturing and intermediate in plant height. The highest yield was observed in VNR3 variety (65.0 quintals ha-1) and VNR4 variety (65.6 quintals ha-1) in the autumn season, and in ĐHS15 variety (66.6 quintals ha-1) and Thai Thinh variety (64.4 quintals ha-1) ha) in the spring season. Seven rice varieties had similar husked rice and milled rice percentage in both seasons. However, the milled head rice percentage fluctuated considerably among varieties. All of rice varieties had low amylose content (13.2% to 16.3% in autumn season and 11.9% to 14.0% in spring season), soft gel consistency and intermediate gelatinization temperature. The total eating quality assessment indicated that HN01 variety was ranked good in quality and the rest of the varieties were ranked intermediate in quality. Based on the characteristics evaluated, Thai Thinh variety was considered as a promising rice variety in Thai Binh province.

Five accessions of Glinus oppositifolius (L.) DC. collected in Tay Ninh (RD1), Hanoi (RD2), Nam Dinh (RD3), Thai Binh (RD4) and Phu Yen (RD5) were grown in field experiments in Spring and Summer-Autumn in in Gia Lam, Ha Noi. The experiment was arranged in a randomized complete block design with 3 replications. The results showed that 5 accessions of Glinus oppositifolius planted in the spring crop exhibited better growth, high yield and higher quality than the summer-autumn crop. The growing duration ranged from 150 to 159 days. In the summer-autumn crop, Glinus oppositifolius plants aged quickly, the growing duration ranged from 120 to 125 days. Among the accessions, RD3 accession collected in Nam Dinh exhibited superiorities, i.e. good growth, good development, high yield and acceptable active ingredients in both spring and summer-autumn crop.

The study aimed to evaluate agro-biological characteristics, yield, quality, and combining ability of self-inbreeding lines and to select F1 hybrid waxgourd combinations through survey and variety comparison experiments at Field Crops Research Institute, Hai Duong Province. Based on combining ability evaluation of 31 lines of fourth self-inbreeding generation,6 wax gourd lines were selected, namely BA6-3-7, BB3-4-5, BB5-6-4, BB7-3- 6, BF5-6-4 and BF9-3-2 with high general combining ability in terms of yield. At the same time, a combination of hybrid wax gourd designated D5/D2 (BF5-6-4/BB3-4-5; named VC21) was selected. The VC21 wax gourd grew well and had good resistance to downy mildew and powdery mildew in both spring-summer and autumn-winter cropping seasons. The VC21 variety had a growth period of 70-75 days from planting to the first harvest, about 105-110 days to the end of harvest and plant height of 370.9-405.2cm. The fruit weight was 1.45-1.51kg and yield of 50.04-57.76 tons/ha. The gourds showed dark green skin, light green flesh with dry matter content of 4.8%, fiber of 17.30%, total sugar of 2.45% and vitamin C content of 4.75mg. VC21 wax gourd variety had fruit shape, fruit weight and quality suitable to consumer preference (fruit length of 39.7-42.8cm, fruit diameter of 7.5-7.8cm, flesh thickness of 2.3-2.5cm).

This study aimed at identifying the substrate and watering regime suitable for potted jungle flame. Two independent experiments were conducted on the red-flower jungle flame and designed in a randomized complete block design with four treatments and three replications. The substrate treatments were CT1 (100% soil), CT2 (soil - smoked rice husk, 1:1, v/v), CT3 (soil - coir powder, 1:1, v/v), and CT4 (soil - smoked rice husk - coir powder, 1:1:1, v/v). The watering treatments included: CT1 (control, watering once every three days), CT2 (adjusting the watering based on the seasonal weather), CT3 (watering once a day), and CT4 (watering once every two days) on the common substrate of soil - smoked rice husk - coir powder (1:1:1, v/v). The results showed that at 230 days after planting, soil - smoked rice husk - coir powder substrate (CT4, 1:1:1 v/v) and watering every two days were best for plant growth and development and proved suitable for potted red-flower jungle flame.

In this study, Listeria monocytogenes was isolated from 130 chicken meat samples collected from 5 supper markets at Gia Lam and Long Bien districts, Ha Noi city to determine prevalence and antibiotic reristance profile of the isolates with 12 antibiotics, i.e. ceftriaxone, cefoxitin, cefepime, ciprofloxacin, ampicillin, meropenem, gentamicin, trimethoprim/ sulfamethoxazole, tetracycline, vancomycin, azithromycin, and florfenicol. The results showed that 25.4% (33/130) of samples were positive with L. monocytogenes. The antibiotic resistance rate of the isolated strains ranged from 0 to 69.7%. The majority of the isolates belonged to the serotype 1/2b (63.5%), followed by 1/2a (36.4%). The resistance to cefoxitin was most common (69.7%), followed by tetracycline (66.7%), and ampicillin (60.6%). No isolate was found resistant to meropenem, cefepime, azithromycin and florfenicol. Notably, 66.7% (22/33) of the isolates exhibited multidrug resistance. Fifteen isolates resisted 3-4 antibiotics (45.5%) and 7 isolates resisted 6-7 antibiotics (21.2%).

This study aimed to evaluate the effect of stocking density on growth, survival, and stress of Scatophagus argus (Linnaeus, 1766). The experiment was conducted in three replicates with three stocking density treatments (15, 30, and 60 fish/m3) using a completely randomized design. The results showed that the growth performance and feed conversion ratio (FCR) were significantly different at different levels of stocking density (P <0.05). The highest growth rate of fish was observed at treatment 15 fish/m3, followed by 30 fish/m3, and then 60 fish/m3) (P <0.05). Analysis of stress indicators when fish was stocked at different densities showed that the higher stocking density, the much higher concentrations of glucose, cortisol, and red blood cells, and FCR (P <0.05), but lower white blood cells (P <0.05). However, stocking density did not affect the survival rate of Scatophagus argus (P >0.05). These findings indicated that high stocking density of Scatophagus argus affects the growth and feed coversion ratio, and causes stress on the fish.

The research was conducted to assess some factors influencing the development of land fund in Cao Bang province. Data were collected from 390 organizations, households and individuals related to land fund development by interview using prepared questionnaire. Exploratory Factor Analysis (EFA) method and Multile Regression Analysis were employed to analyze the data gathered. The research results identified 21 factors which were divided into 4 groups that showed significant influence on the development of land fund in the descending order: the factors related to state with the coefficient b = 0.381 (accounting for 37.29%), the factors related to investors with the coefficient b = 0.233 (accounting for 33.15%), the factors related to people whose land is withdrawn for land fund development with the coefficient b = 0.133 (accounting for 15.18%), and the factors on natural conditions and infrastructure with the coefficient b = 0.122 (accounting for 14.38%). The study has proposed several solutions to enhance the development of land fund, i.e. issuing appropriate investment policies to attract investors and compensation, support and resettlement policies when land withdrawn by the State, reasonable allocation of capital, expeditious development of the sector planning plan, improving infrastructure, determining reasonable land rental price, and strengthening the propaganda and dissemination of laws.

The study aimed to determine the factors affecting the valuation of residential land for compensation, land auction of land use rights and, thereby, propose solutions for improvement of land valuation in Tu Son city, Bac Ninh province. The study directly investigated 148 people related to land valuation through 2 steps in collecting data for building a model of affecting factors. The data were evaluated through testing criteria using SPSS 24.0 software. Therewere 20 factors out of a total of 22 hypothetical factors belonging to 6 groups of factors satisfied the testing criteria. The impact rate of the groups of factors ranged from 8.42% to 26.59%. The group of land price factors had the most impact while the group of land plot factors had the least impact. Some solutions were proposed, viz. removing the land price bracket, implementing the State's pre-purchase land use rights, publishing land prices, improving the capacity of appraisers, independent price appraisal organizations, and the responsibilities of those who sign and approve land prices, completing the land price information system,; considering some land plot factors when valuing.

Resveratrol as a phytochemical with strong antioxidant properties was found in certain berries and in peatnut roots. This study was conducted to induce adventitious roots of peatnut and investigate some factors affecting the growth of adventitious roots as a source of resveratrol. Leaf explants were cultured on MS medium supplemented with α-NAA, IBA and IAA (1-10 mg/l), sucrose (20-50 g/l) under light and dark culture conditions to induce formation of adventitious roots. The results showed that direct formation of adventitious roots from peanut leaves was best on MS medium containing 5 mg/l α-NAA and 30 g/l sucrose cultured in full darkness with 87.5% rooting rate and 5.5 roots per explant after 6 weeks of culture. The growth of adventitious roots (1.0cm in length) when cultured on MS medium sustained better than ½ MS, B5 and ½ B5 media. A positive effect of auxin including α-NAA, IBA and IAA on adventitious root growth was found. The maxium percentage of adventitious root segment producing lateral roots and highest number of lateral roots/segment, (100% and 4.9 roots, respectively) were obtained on MS + 1 mg/l α-NAA after 6 weeks of culture.

The present study analyzed the current situation and proposed solutions to develop Shan tuyet green tea production in Bac Yen district, Son La province. The study surveyed 90 Shan tuyet tea producing households, 15 government officials, 5 input suppliers and consumers in Bac Yen district. Descriptive and comparative statistics and costs and returns analysis were used to assess the current situation of Shan tuyet tea production development in Bac Yen district. The results showed that the productivity of Shan tuyet tea in Bac Yen was low and the processing and preservation technology were backward. In addition, the supports in the past time were not timely and at low level; the infrastructure of the tea production area was still lacking and weak together with a weak market connectivity rendering lower efficiency of Shan tuyet tea production as compared to its potential. Therefore, a number of solutions for the development of Shan tuyet tea production in Bac Yen district were proposed such as planning tea areas, investing in infrastructure, strengthening agricultural extension and technology transfer, capital support, trade promotion, and tea production development associated with tourism development.

Chrysanthemum is the main crop of Nghia Trai medicinal village, Tan Quang commune, Van Lam district, Hung Yen province. Through the activities of synthesizing and comparing secondary data from reports of the People's Committee of Tan Quang commune and through survey data of 45 households, the study assessed the current situation of development of chrysanthemum production in the area. The results showed that chrysanthemum brought a high average mixed income compared to various other traditional crops. Chrysanthemum shows great potential for production, but there are a number of barriers affecting the development of chrysanthemum production, such as fragmented land scale, manual and small-scale production, and fluctuating selling prices. Therefore, in the future, authorities at all levels and relevant actors should soon implement some specific solutions to promote the development of chrysanthemum production in the area.

It is believed that scientific research participation helps students enrich knowledge, improve creative thinking, and open up good career opportunities. However, the participation of undergraduate students in this meaningful activity remained weak in both quantity and quality. This article analyzed the factors affecting students' intention to participate in scientific research based on data collected from 350 students studying at the Vietnam National University of Agriculture (VNUA). Cronbach Alpha test and Exploratory Factor Analysis indicated four esstential factors promoting students' intention to participate in scientific research: student's attitude and capacity; encouragements of the VNUA, Faculty and lecturers; and conditions for conducting scientific research. In particular, the external environment has a stronger impact than the internal factors of students. These results are important foundations to propose recommendations to create a suitable research conditions and motivate students to carry out scientific research.

This paper aimed at exploring critical determinants of farmers’ adoption of sustainable farming practices in agricultural areas contributing to anthropogenic global warming. The binary logistic regression model with the help of SPSS 24.0 shows that “market accessibility”, “stability of livelihood” and “the impact of extreme weather conditions” had a significant influence on the farmers’ choice of low-carbon farming practices (P <0.05). These findings provide a different understanding to current literature that concludes the impacts of age, gender, education, finance, farm size, etc. on farmers’ adoption of climate change adaptation strategies. This paper argues that farming practices that demonstrate market competitiveness and stability should be a natural starting point for mobilizing farmers to transition towards a low-carbon agriculture.

Social strata/class is a basic concept in social sciences, and it is a term commonly used today in the development research in Vietnam. This study, first summarized narrative review of social strata, focusing on some basic terms 'social strata', 'social class', and 'social stratification' and then reviewed the current situation, process and trends in applying the concepts of social strata in research and development activities in Vietnam’s market oriented economy period with socialist orientation, thereby recommending research orientation towards a reasonable social strata structure according to the country's socio-economic development goals to 2030.