Vol. 21 No. 8 (2023)

The study was conducted to determine the efficacy of biofertilizers carrying strains of nitrogen-fixing and phosphorous-solubilizing purple non-sulfur bacteria (Rhodopseudomonas palustris) TLS06, VNW02, VNW64 and VNS89 (CPVS-NP) on black beans growth and yield. The experiment followed a completely randomized block design with 5 treatments and 4 replications, each of which corresponded to a pot. The treatments were (i) 100% N, P;(ii) CPVS-NP combined with 75% N, P;(iii) CPVS-NP combined with 50% N, P;(iv) CPVS-NP only;(v) not supplying CPVS-NP and no chemical fertilizers. The results showed that supplying CPVS-NP combined with75% N, P increased PNSB density and obtained the plant height, leaves number per plant, leaf length, leaf width and the branches per plant equivalent to or higher than those in the treatment fertilized with100% N, P. Supplying CPVS-NP plus 75% N, P enhanced yield by 22.0% compared to that in the treatment fertilized with 100% N, P.

The study aimed to evaluate the effects of different levels and forms of nitrogen fertilizer on the growth, yield and contents of pharmaceutical substances of Javanese ginseng. The experiment was laid out in a randomized complete block design with three levels of nitrogen (60, 75 and 90kg N/ha) and three ratios of N-NH4+:N-NO3-(0:100, 50:50 and 100:0) with three replications. The results showed that the height, number of leaves, leaf area, SPAD index, fresh weight of roots and dry matter of Javanese ginseng increased significantly with the increase of nitrogen rate. Different ratios of N-NH4+:N-NO3- did not significantly affect the growth and development parameters of Javanese ginseng. In both harvest seasons, the NH4+form at 75kg N/ha resulted in the highest yield and saponin and flavonoid content, while maintaining NO3-content at optimal range.

This studywas designed toevaluate the heterosisand general combining ability (GCA) of ten S3purple cherry tomato lines based on the Line×Tester model to select elite parental lines with high combiningability in terms of yield and quality. Ten cherry tomato lines, three testers, thirty crosses,andtwo checks were evaluated based on 11 agronomic traits in 2022 Autumn-Winterseasonin Hanoi under polyhouse. The results showedthat purple tomato varieties can be created by crossing purple tomato lines with purple or red cherry tomato lines. The mid parent and best parent heterosis showed negative values in almost all traits and crosses investigated. D10 hada significant positive GCAeffectformarketable yield. Three lines viz.,D3, D6, and D9 had significant positive GCAeffect fortotal soluble solids content.Two dark purple cherry tomato crosses viz., D10×T3 (38.1 tons/ha, 9.0Brix) and D6×T3 (35.2 tons/ha, 9.8Brix) showedbreeding potential to develop new cherry tomato lines in the next segregation generation

This study aimed to construct a database of genetic diversity based on morphological characteristics for selection and breedingmini lotus varieties and demand for ornamental lotus in Vietnam. Thirty accessions of mini lotus(denoted as S1-S30) collected in Hanoi, Hung Yen and Dong Thap were grown for characterization at Vietnam National University of Agriculture in 2022. Through evaluating the morphological characteristics., the results showed that diversity expressed in color of young leaves, spines on leaves, spines on petioles,color of buds,color of leaves, etc. Two potential accessions were selected with very small size of plant, leaves and flowers that can be classified as supermini for decorating in small pots on the table (S28 and S12). The analysis of genetic relationships based on 17 agro-morphological traits showed that 30 accessions of the mini lotus group were quite different. The genetic similarity coefficient of 30 accessions ranged from 0.4-1.0 and the accessions were classified into 3 groups at the similarity coefficient of 0.55, differing in some morphological traits.

This research was conducted to identify avocado trees with high quality of fruit as a source ofbreeding new avocado species. The survey was performed on individual avocado tree which had capable of fruiting in Tien Giang. The selected avocado trees recorded flowering characteristics., ratio of flowers on the tree, described fruit characteristics., and analyzed fruit quality criteria. In this study, four individual avocado trees were selected, displaying a capable of self-pollination and cross-pollination with flowers on the same tree, denoted as Cai Lay 1, Cai Lay 2, Cai Lay 3 and Cho Gao. They were well adapted to the conditions in Tien Giang province, yielding 70-120kg of fruit per tree every year. On average, the percentage of self-pollinated flowers accounted for about 33.31%, the group of semi-pollinated flowers accounted for about 11.25% and group A/group B flowers (which could not pollinate) accounted for about 51.45%. Those trees possessed fruit pulp moisture (ranged from 72.6-79.9%), fruit hardness (ranged from 1.03-1.37N) and high brix elevation (ranged from 10.0-12.0%). Out of them, Cai Lay 1 avocado indicated a higher lipid content (20.5%) and protein content (3.08%) than the Booth avocado varieties of class I, avocado 034 grown in Da Lat and avocado 034 grown in Tien Giang.

Thí study aims to evaluate the effectiveness of herbal product PremixHad and doxycycline on feed intakes, feed conversion ratios and villus measurements of small intestine in Swiss albino mice via growth parameters and micro-morphological measurements. The results showed that PremixHad supplement in feed with concentrations of 1.25%; 2.5%; 5.0% and doxycycline (2g per liter of drinking water) were safe for the mice. Supplement concentation at 1.25% improved BW gain. PH and doxycycline increased feed efficiency via the decrease of FCR. PH showed good effects on height, width and height/width ratios of duodenal and jejunal villi but no effect on ileal villus sizes. Meanwhile, doxycycline decreased these parameters in the mouse illeum. It can be said that PH is safe with positive effects on the intestinal health of Swiss albino mice and should be tested in livestock animals to confirm the effectiveness.

In order to take advantage of the abundant source of pomelo peel, this study was conducted to isolate, select and apply lactic acid bacteria strains in the production of fermented product from pomelo peel. Lactic acid bacteria strains were isolated from 7 samples of commercial Nem chua (Vietnamese fermented pork roll), evaluated for their antibacterial ability and high lactic acid production in MRS broth medium supplemented with D-glucose (20 g/l) as well as screened for lactic acid fermentation of Nam Roi pomelo peel. The results showed that 13 lactic acid bacteria strains were isolated from 7 kinds of Nem chua. All isolates had antibacterial activity against B. subtilisand created an antibacterial range of 2.0 to 14.33 mm. Evaluation of fermentation ability on MRS broth medium showed that the strains TP, XP2, OM2, and CR2 produced the highest lactic acid content in the range of 19.6 to 20.33 g/l. The strains TP and DT2 were selected for production of fermented pomelo peel with high acid production and good taste. The strains DT2 and TP were identified as Lactobacillus plantarumand Lactobacillus fermentum, respectively.

Cellulase is an enzyme used in many fields, such as agriculture, industry, and medicine. Among microorganisms capable of synthesizing cellulase, bacteria are evaluated as having high enzyme activity, stability, and limited environmental pollution. This study was conducted to isolate and characterize bacteria strains with high ability to degrade cellulose, which can serve as a basis for research treatment methods for cellulose-containing agricultural by-products more effective. From wood processing by-products collected in two provinces, Hung Yen and Hanoi, by inoculating method on a selective medium containing 1% CMC (Carboxymethyl cellulose), 23 strains of bacteria capable of degrading CMC (carboxymethyl cellulose) were isolated, two strains, C4 and C2,1 were potential strains showing high ability to degrade carboxymethyl cellulose. Colony morphology, cell morphology, and biochemical characteristics showed that both strains belonged to genusBacillussp. After evaluating effects of culture conditions on cellulase activity of two selected strains, strain C4 synthesized cellulase with the highest activity when cultured in LB medium, shaking condition, at 35C, pH 8.0 for 24 hours; while strain C4 synthesized cellulase with the highest activity when cultured in LB medium, shaking condition, at 35C, pH 6,0 for 72 hours. Finally, evaluation of the ability to decompose rice straw and rotten wood in vitroshowed that the efficiency of these strains increased 3.02-4.22 times compared with the control.

This study aimed to evaluate leadership capacity of CEOs in small and medium-sized enterprises in Hanoi. We randomly selected 225 small and medium-sized enterprise CEOsand 225 of their subordinates, applying Cronbach's Alpha method, Exploratory Factor Analysis, Chi- Square Test, GAP matrix. The findings showed that surveyedleadership capacity of small and medium - sized enterprises reached the basic level. Meanwhile, some factors i.e.,human resources knowledge, corporate social responsibility knowledge, self-leadership knowledge, building vision and strategy skills were lacking. There should be synchronous solutions from CEOs, governments, and educational institutions in order to enhance their leadership capacity.

This study aimed to analyze the current situation and propose solutions to improve the quality of cadres and civil servants at the commune level in Tan Lac district, Hoa Binh province. The study conducted a survey of 130 representative respondents and utilized descriptive statistics., comparison and scoring and ranking methods for data analysis. The research results showed that the quality of cadres and civil servants at the commune level in Tan Lac district has met the current job requirements and was improving in all aspects. Basically, commune-level civil servants in Tan Lac district experienced professional qualifications. They possessed experience and understanding of the actual situation of the locality; spirit of solidarity and responsibility, acceptable working style, morality andlifestyle. However, there were still some commune-level civil servants who are still limited in terms of trained professional knowledge, problem solving skills and working attitude. Some solutions were proposed to improve the quality of cadres and civil servants at the commune level in Tan Lac district are as follows: Improving the quality of planning for cadres and civil servant development at the commune level; Renovating the recruitment of cadres and civil servants at the commune level; Strengthening the training and retraining of cadres and civil servants at the commune level; Completing the assessment of cadres and civil servants at the commune level; and Accelerating the implementation of solutions to create work motivation for cadres and civil servants at the commune level.

High-tech agriculture is an indispensable direction to respond to climate change and the increasing demands of domestic and international markets, Lam Dong is the leading province in the application of hi-tech agriculture in agricultural development in Vietnam.This study aimed to assess the current situation of hi-tech application of agricultural cooperatives in Lam Dong province. Primary data was collected from 25 agricultural cooperatives have applied high technology, 05 others have not applied yet; and related stakeholders in the province.The results showed that agricultural cooperatives applied high technology in production increased productivity and product quality and the economic efficiency was about 2 times higher than those practising conventional production. However, the rate of high-tech agricultural cooperatives was still low and not synchronous in application, mainly in the production stage and faced many barriers in the development process such as land and capital. Besides, the level of the managers and cooperative members were still limited. Therefore, some main solutions were proposed to promote the development of agricultural cooperatives in high-tech applications in the area.

The Covid-19 pandemic has seriously affected all aspects of people's life. Migrant workers returning to the locality during the outbreak, were most vulnerable to the impact of the Covid-19 pandemic. Young female migrant workers, particullarly, had a lot of vulnerability and risks when returning to their hometowns. Therefore, thisresearch focused on understanding the impacts of the Covid-19 pandemic on employment, income, quality of life and psychology of young female migrant workers through a survey of 110 households with young female migrant workers who had to return to their localities in 6 communes in the coastal area of Thua Thien Hue province. Research results showed a significant decrease in income, employment, quality of life and anxiety during the Covid-19 pandemic occurence. Young female migrant workers were difficult to access and receive the supports of the government, as well as how to choose adaptation solutions when the Covid-19 pandemic is under control. Research recommended policies regarding employment, vocational trainings, physical and mental health care to support young female migrant workers tobuild their adaptive capacity to socio-economic, environmental and pandemic shocks.

The present article was based on data andinformation collected from officialreports, in-depth interviews with localofficials, and field surveys of production units to assess the current situation of thedevelopmentofhi-tech agricultural zones in Bac Giang province. The research results show that there were 14 hi-tech cultivation zones that have been established and developed as planned, focusing on: vegetables, flowers, tea, lychee, citrus,and mushrooms. Various hightechnologies have been put into application such as breeding new plant varieties and crop management practices with automatic equipment. Consumption linkages within zoneswere also established and developed. However, technical infrastructure for hi-tech agricultural production has not been synchronously invested from production to harvesting, preliminary processing, preservation and product consumption,lack of core technologies, especially information technology, automation technology, and biotechnology; andpotential risks. Therefore, the local government should have stronger support policies for the development of the province's hi-tech agriculturalzones in the coming time.