• Journal of Agricultural Extension & Community Development
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• v.10 no.1
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• pp.57-76
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• 2003

This study examined th socioeconomic returns to agricultural research in Korea, using multivariate time series technique and Akino-Hyami formula. Results showed that the socioeconomic returns were quite competitive with internal rates of 49.18% and 56.04% for agricultural research and horticultural research respectively. The lagged response to the investment in research varied according to the type of production: agricultural production responded to agricultural research shock about three tears after the shock, while horticultural and livestock productions responded only after abort seven, and ten years, respectively. The magnitudes of the impacts of investment, however, showed a similar pattern for the three types of production: after responding to the shock, the impact increased until a peak was reached and then declined and got down to zero after some years. The peak was reached within five, seventeen, and twenty tears after the intial expenditures for agricultural, horticultural, and livestock productions, respectively. Moreover, the impacts disappeared about thirty tears after the initial expenditures for all three types of production. These findings were consistent with the results from previous literature on agricultural research, which indicated that the lag lengths of the response to investments on research were between seven and thirty years.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.116.1-116
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• 2003

Fusarium oxysporum f. sp. fragariae is a fungal pathogen causing wilt disease on strawberry. The RAPD and RFLP of IGS region of rDNA were used to identify genetic affinity among 22 isolates of F. oxysporum f. sp. fagariae obtained from various location of major strawberry cultivating areas in Korea. Approximately 2.6kb DNA fragment was amplified with primer CNS1 and CNL12, and polymorphisms were observed with Avail and HinfI. A dendrogram was constructed using the UPGMA for cluster analysis. Eight distinct groups were clustered based on the banding pattern obtained from RAPD and rDNA RFLP. There was high level genetic variation among Korean isolates of Fusarium of sporum f. sp. fragariae.

• Korean Journal Plant Pathology
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• v.3 no.2
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• pp.85-92
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• 1987

The present researches were carried out to differentiate the species of Colletotrichum by elecrophoretic method. C. gloeosporioides, C. dematium and Gloeosporium fructigenum could be differentiated by the isozyme patterns of esterase, leucine aminopeptidase, acid phosphatase and glutamic oxaloacetic transaminase. Especially. G-strain and R-strain of C. gloeosporioides were differentiated by the enzyme patterns. The G­strain damaged all stage fruits (green and red fruits) of Capsicum annum. The R-strain could not infect the unripe (green) fruits, but it could damage only ripe (red) fruit of Capsicum annum.

• Journal of Biosystems Engineering
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• v.32 no.6
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• pp.383-388
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• 2007

In precision farming, proper calibration and operation of a variable rate machine are critical to reduce input of agrochemicals and to ensure productivity and quality of agricultural products. As an effort to introduce precision farming to rice production in Korea, a pneumatic granular applicator was developed. This investigation intended to evaluate the application performance such as application accuracy, application uniformity and to suggest how to adjust the blow-heads to get uniform application pattern, and to suggest a practical way of adjustment of the blow-heads for uniform application. Tests to evaluate the application performance were conducted. The application uniformities (CV) in both transverse direction and longitudinal direction were less than 15% and application accuracy was greater than 81%. A simple method for adjusting the inserting length of blow-heads was suggested.

• Microbiology and Biotechnology Letters
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• v.48 no.2
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• pp.138-147
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• 2020

Various microorganisms play important roles in food fermentation, food spoilage, and agriculture. In this study, the biotype of 54 yeast and bacterial strains having high potential for utilization in food and agriculture, including Candida spp., Lactobacillus spp., and Acetobacter spp., were characterized by matrix-assisted laser desorption/ionization time-of flight mass spectrometry (MALDI-TOF MS). This characterization using a fast and robust method provides much-needed information on the selected microorganisms and will facilitate effective usage of these strains in various applications. Importantly, the unique protein profile of each microbial species obtained from this study was used to create a database of fingerprints from these species. The database was validated using microbial strains of the same species by comparing the mass spectra with the created database through pattern matching. The created reference database provides crucial information and is useful for further utilization of a large number of valuable microorganisms relevant to food and agriculture.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1498-1503
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• 2007

To identify novel crystal proteins, Bacillus thuringiensis 2385-1 was isolated from Korean soil samples and characterized. The H-serotype of 2385-1 was identical to that of subsp. kenyae (H4a4c), and its crystal toxin was bipyramidal-shaped. However, 2385-1 showed a much higher toxicity towards Plutella xylostella and Spodoptera exigua larvae than subsp. kenyae. In addition, the crystal protein profile and plasmid DNA pattern of 2385-1 differed from those of subsp. kenyae. To verify the crystal protein gene types of 2385-1, a PCR-RFLP analysis was performed, and the results revealed that 2385-1 contained two novel cry1-type crystal protein genes, cryl-5 and cry1-12, in addition to the crylJal gene. The deduced amino acid sequences of cryl-5 and cry1-12 showed a 97.9% and 75.7% sequence similarity with the CrylAb and CrylJa crystal proteins, respectively. Among the novel crystal proteins, Cry1-5 showed a high toxicity towards P. xylostella and S. exigua larvae. In conclusion, B. thuringiensis 2385-1 is a new isolate in terms of its gene types, and should be a promising source for an insecticide to control lepidopteran larvae.

• The Korean Journal of Food & Health Convergence
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• v.5 no.3
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• pp.1-5
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• 2019

The field experiment was conducted in vegetable area, Institute of Horticultural Sciences in University of Agriculture, Faisalabad in order to recognize morphological and fruit growth pattern and yield of Tinda (Praecitrullus fistulosus) gourd germplasm lines. Sixteen germplasm lines in which one line is used as check are included were sown and grown on flat beds in field. The field experiment was arranged as randomized complete block design (RCBD) with three replications. Data on days to maturity, fruit per vine, fruit weight in grams, fruit diameter and total yield obtained were recorded. The fruit texture is marked as phenotype parameter. All parameters were collected and then analyzed statistically. All lines and replications showed different results among each other according to parameter. The maximum DTM (days to maturity), F/P (fruit per plant), FW (fruit weight), FD (fruit diameter) and Yield were recorded was $L_0$ (68.66), $L_3$ (1.66), $L_{10}$ (248.33), $L_{13}$ (8.50) and $L_0$ (599.33) and the minimum were recorded was $L_1$ (56), $L_{11}$ (0.33), $L_0$ (198), $L_9$ (7) and $L_4$ (421) grams respectively. All lines showed smooth texture of fruits with no hairs when mature at harvesting stage.

• Korean Journal of Agricultural Science
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• v.20 no.1
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• pp.34-42
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• 1993

Effects of salt concentrations on the cell growth and the pigment accumulation were investigated in cell suspension culture of Vitis vinifera and Phytolacca americana L.. The growth pattern of vine cell in control was showed the normal exponential growth pattern, but in the dilution media delay the exponential growth pattern from 4 to 8 days after culture. Maximal accumulation of anthocyanin was observed at 12 days after culture in all treatments. In cell suspension culture of Phytolacca, accumulation of betacyanin occurred in parallel with the cell growth pattern and maximal accumulation of betacyanin was observed after 8 days of culture. In the vine cell culture, the cell growth was showed the peak at 87.6mM of sucrose in the medium and reduced at over this concentration. Maximal anthocyanin accumulation was showed at 146mM of sucrose. In the higher concentrations of sucrose, the cell growth was rapidly decreased, but the accumulation of anthocyanin was not. Otherwise, in case of Phytolacca cell culture, betacyanin accumulation was showed in parallel with the cell growth increased with sucrose concentration. It was suggested that the anthocyanin of vine and the betacyanin of Phytolacca were controlled by different mechanisms.

• Korean Journal of Medicinal Crop Science
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• v.4 no.1
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• pp.12-18
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• 1996

This study was investigated to improve the rate of the seed germination of Wasabia japonica with $GA_3$ and BAP. The germination rate was 36% with 100ppm $GA_3$ only and 32% with 10ppm BAP only, while that was 65% with combination of 100ppm $GA_3$ and 10ppm BAP compared to that of 7.5% in control. This results show us that the most effect of germination rate was with 100ppm $GA_3$ and 10ppm BAP. Mutagenesis was induced with mutagen, EMS and colchicine. Before the germination, the survival rate was 62% with 0.5% colchicine compared to that of 7% in control. After the germination, the 85% of developed seed was alive with treatment of 0.5% colchicine and 55% of those was alive with 0.06% EMS compared to that of 8% in control. We analyzed the karyotype and isozyme pattern of Wasabia japonica induced with colchicine and EMS. The tetratype of Wasabia japonica was observed from Wasabia japonica treated with 0.5% colchicine. whereas it was not observed with 0.06% EMS. The peroxidase pattern of colchicine treated Wasabia japonica was different from nontreatment. but that of EMS treated Wasabia japonica was the same with normal one.

• Korean Journal of Agricultural Science
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• v.31 no.2
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• pp.123-134
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• 2004

Since 1989, 9 major complex have been invested with government funds, for the purpose of developing agricultural tourism to increase agricultural income and job opportunity, as well as providing urban population leisure opportunity. However, systematic and comprehensive approaches were rarely done in analyzing its economic impacts. This study, therefore, focuses on analyzing tourism effect and its economic value and implication for a representative rural tourism site,"Daeho rural tourism complex". To analyze travel pattern, expenditure pattern, and degree of satisfaction from travel to Daeho complex, Travel Cost Method(TCM) was employed based on survey method. Results from linear model with statistical significance implies that tourism benefit for each visitor is 28,373 won and total annual benefit for the Daeho site is 7 billion won. Considering annual benefit stream, the present value of total benefits are 132.9 billion won and 70 billion won at 5% and 10% of discounting rate, respectively. Using the values of benefit estimated from this study and investment cost, B/C ratio, IRR, and NPV were calculated to be 1.01, 1.67 billion won, and 5.19% at 5% of discounting rate. These results could be directly compared with the previous analyses.