• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.35-53
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• 1974

A series of experiment was conducted to investigate the effects of the level of dietary Protein (soybean meal) and carbohydrate (sucrose) on the growth rate, feed efficiency, nutrients digestibility and amylase activity of larvae at 5th instar. The results obtained from the experimentation are summarized as follow： (1) It was found that the body weight gain, cocoon quality and feed efficiency of the 5th instar larvae were significantly affected by the level of protein and carbohydrate in the artificial diet. Present data revealed that the proper level of dietary protein and carbohydrate would be the most important factor for the optimum growth of larvae. (2) In the amount of diet consumption, the group of larvae gained more body weight consumed more diet than the group gained less amount of body weight. (3) Digestibility of nutrients was improved as the level of protein in the diet increased, although the level of dietary carbohydrate did not exert any positive results. (4) It was observed that the amylase activity in digestive juice was stimulated by the increasement of dietary carbohydrate. However, no correlation between the level of dietary protein and carbohydrate was detected in the amylase activity. (5) Analytical data indicated that the amount of protein or carbohydrate excreted through feces and urine was proportional to the content of protein or carbohydrate in artificial diet. The group o( larvae consumed the diet contained high protein excreted more protein and less nitrogen free extract than did the group received low protein diet. Likewise, the group of larvae fed high dietary carbohydrate excreted more nitrogen free extract and less protein through excreta than the group consumed low carbohydrate diet group. (6) Although the amylase activity of the larvae received the artificial diet was higher than the larvae received natural diet (mulberry leaf), the rate of body weight gam and the quality of cocoon produced from the natural diet group was better than the artificial diet group. It is, thus, concluded that feeding the larvae by the artificial diet may net be recommendable. (7) It was determined that the best level of protein (soybean meal) and carbohydrate (sucrose) in artificial diet was found to be 40g and 0g, respectively when it was fed to the 5th instar larvae. (8) It may be concluded from the results obtained that the artificial diet that could stimulate the activity of amylase nay not be recommendable for the practical larvae feeding Purpose due simply to the Poor economic return from this diet than natural diet.

• Journal of the Korean Society of Food Culture
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• v.9 no.2
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• pp.111-118
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• 1994

The purpose of this study was to understand dietaty culture of the Buddhist priesthood in Seoul and Kyungnam. This survey was carried out through questionnaries and the subjects were 26 temples and hermitages. The results of this study can be summarized as follow: 1. Most of the Buddhist priesthood takes meal three times for a day regularly. The substitution food was used mainly rice gruel, fruits, powder of roasted grain, kinds of cookie and confectionary, kinds of steamed dish and milk. 2. The seasoning substances were used necessarily soy sauce, soybean paste, salt and sesame, sesame oil, vegetable oil, and used rarely Jepi powder, red powder, chinese pepper and M.S.G. 3. Eating table was used chiefly for Buddhist priethood and a vistor, and tea and cookie, D'ock, noodle were used often. Event and party foods of temple were used Bibimbab, Ogokbab, Yagbab, D'ockguk, soybean of noodle. 4. Offering food to Buddha was used to Five-offered to Buddha(香, 燈, 茶, 果, 米) primarily and religious food was used scarcely. 5. Special food was used D'ock, hand made cookie and confectionaries, kinds of chinish medicine tea and pine needle tea. Injulmi and Julpyun were prepared most frequently, and used to mixed rice flour with mugwort now and then. Coating and filling powders for D'ock were used to red bean, mung bean and soy bean. Kinds of hand made cookie were Yagkwa, Kangjeong, Dasik, Jungkwa and Yangeng. Beverages were thick hot beverage, kinds of leaf tea, chilled beverage, Yaksu mixed with soy sauce and bamboo salt, kinds of chinese medicine tea, milk and milk products and pine needles tea. 6. Preserved foods were used edible mountain herbs and seaweeds in drying and frying.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.579-596
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• 1997

A simulation study was carried out to delineate potential effects of the lake-induced climate change on crop productivity around Lake Imha which was formed after a multi-purpose dam construction in Andong, Korea. Twenty seven cropping zones were identified within the 30 km by 25 km study area. Five automated weather stations were installed within the study area and operated for five years after the lake formation. A geostatistical method was used to calculate the monthly climatological normals of daily maximum and minimum temperature, solar radiation and precipitation for each cropping zone before and after the dam construction. Daily weather data sets for 30 years were generated for each cropping zone from the monthly normals data representing "No lake" and "After lake" climatic scenarios, respectively. They were fed into crop models (ORYZA1 for rice, SOYGRO for soybean, CERES-maize for corn) to simulate the yield potential of each cropping zone. Calculated daily maximum temperature was higher after the dam construction for the period of October through March and lower for the remaining months except June and July. Decrease in daily minimum temperature was predicted for the period of April through August. Monthly total radiation was predicted to decrease after the lake formation in all the months except February, June, and September and the largest drop was found in winter. But there was no consistent pattern in precipitation change. According to the model calculation, the number of cropping zones which showed a decreased yield potential was 2 for soybean and 6 for corn out of 27 zones with a 10 to 17% yield drop. Little change in yield potential was found at most cropping zones in the case of paddy rice, but interannual variation was predicted to increase after the lake formation. the lake formation.

• Applied Biological Chemistry
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• v.19 no.3
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• pp.172-183
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• 1976

RNA, DNA and other phosphorus fractions were determined in the leaf and root of soybean plants different in phosphorus sensitivity grown in $NH_4-N,\;NO_3-N$ and urea medium. The phosphorus sensitive cultivars contained higher ASIP (acid soluble inorganic phosphorus) than the tolerant cultivars with all nitrogen sources. ASIP was highest in the urea treated plants and lowest in the nitrate treated plants. Total phosphorus content was mostly affected with increase in ASIP. When ASIP increased, acid solsuble organic phosphorus(ASOP), phospholipids (L-P), RNA-P, residual phosphorus (R-P) tended to increase, while DNA-P showed little change. The percent RNA-P or DNA-P of total phosphorus in the nitrate treated plant was twice that in the ammonium treated plant, which were also higher in tolerant cultivars regardless of nitrogen sources. The percent ASOP in total acid soluble phosphorus $(ASOP/ASP{\times}100)$ decreased as phosphorus sensitivity decreased. Indications are that phosphorus sensitivity depends on the relative sizes of phosphorus metabolic pools. Total dry matter yield was negatively correlated with total phosphorus (r=0.84 significant at 0.01P), ASIP (0.84 significant at 0.01P) and residual phosphorus (0.69 significant at 0.05P). ASOP showed positive correlation with L-P, RNA-P and DNA-P but negative with R-P. RNA-P was significanly correlated only with L-P (0.63 at P=0.01). There was significant interaction (0.01) among nitrogen sources, cultivars and phosphorus metabolic pools. Phosphorus sensitivity and ammonium toxicity appear to be same in view of energy metabolism, that is, the former inhibits the conversion of ATP to ADP (energy releasing) through phosphate potential while the latter inhibits ATP formation (energy storing).

• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.26-37
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• 1987

This studies were conducted to investigate pathgenicity and host range of Colletotrichum dematium isolated from anthracnose of pepper, and phytoxicity of its culture filtrate and the partially purified toxin. The results obtained were as follows. 1. Investigation on the host range of C. dematium has revealed that pepper as well as soybean, tomato, spinach, and beet were highly susceptible, egg plant and water melon were moderately susceptible and stone leek was slightly suceptible, but no symptoms were produced on carrot, tabacco, cucumber and melon. 2. The culture filtrates of C. dematium in Czapeck dox liquid media were toxic to leaves of pepper and caused necrosis and wilting of the plant. The toxicity of culture filtrates was most active at 15 days after fungal growth in Czapeck dox liquid media and the toxin productivity in still culture was higher than that in shaking culture. 3. The partially purified toxic substance was isolated from the culture filtrates by the acetone precipitation method. When cuttings of various pepper cultivars were placed in the toxin solutions, suceptible cultivars and resistant cultivars were equally toxic and showed necrosis and wilting of the leaves. 4. Several other plants such as soybean, tomato and carrot were also affected with the toxin solution by shoot cutting bioassay and showed veinal necrosis, leaf spots and wilting of the shoots. 5. The acetone precipitation toxin affected seed germination of pepper, cucumber, sesame and egg plant and inhibited the growth of root and hypocotyl of the seedlings.

• Korean Journal of Agricultural and Forest Meteorology
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• v.26 no.2
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• pp.127-139
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• 2024

Climate change has increased extreme weather events likewise heatwaves, heavy rain, and drought. Unlike other natural disaster, drought is a slowly developing phenomenon and thus drought damage increases as the drought continues. Therefore, it is necessary to understand the characteristics and mechanism of drought occurrence. Agricultural drought occurs when the water supply needed by crops becomes insufficient due to lack of soil water. Therefore, soil water is used as a key variable affecting agricultural drought. In this study, we examined the spatio-temporal distribution and trends of drought across the Korean Peninsula by determining the soil available water content (SAWC) through a model that integrated soil, meteorological, and crop data. Moreover, an investigation into the correlation between meteorological variables and the SAWC was conducted to assess how meteorological characteristics influence the nature of drought occurrences. During the soybean cultivation period, the average SAWC was lowest in 2018 at 88.6% and highest in 2021 at 103.2%. Analysis of the spatial distribution of SAWC by growth stage revealed that the lowest SAWC occurred during the flowering stage (S3) in 2018, during the leaf extension stage (S2) in 2019, during the seedling stage (S1) in 2020, again during the flowering stage (S3) in 2021, and during the seedling stage (S1) in 2022. Based on the average SAWC across different growth stages, the frequency of upland drought was the highest at 22 times during the S3 in 2018. The lowest SAWC was primarily influenced by a significant negative correlation with rainfall and evapotranspiration, whereas the highest SAWC showed a significant positive correlation with rainfall and relative humidity, and a significant negative correlation with reference evapotranspiration.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.4
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• pp.350-355
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• 1995

This study was conducted to use oyster shells, which have caused environmental problems in the coastal of Korea, as an agricultural material after processing. Physico-chemical components and neutralizing amount on the Ihyun silt loam of crushed oyster shell and slaked lime were examined. In field experiment, the properties of the soil, growth and yield of lettuce, cabbage, spinach, onion, red pepper and soybean were examined by the treatments of the shell(3.68ton/ha) or the lime (2.76ton/ha) with a randomized block design. Particle size of crushed oyster shell consisted of 73.4% of 1~60mesh and 26.6% larger then 61 mesh and contents of CaO, OM, and $P_2O_5$, etc. were 55.5%, 1.3%, and 0.29%, respectively. The requirement of the shell to neutralize the soil was 130~135% of the lime, but after 24months, it was the same. The application of the shell increased the contents of available $P_2O_5$ and $SiO_2$ exchangeable Ca in used soil. The shell tratment increased the leaf height, leaf width, etc. of the examined plants, and the yields 6~154% according to examined plants, as compared with the nonliminged, indicating that the shell possesses a great potential as an agricultural material with the same effectiveness as the lime.

• Korean Journal of Agricultural Science
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• v.17 no.1
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• pp.1-8
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• 1990

The paper board sludge(PBS) itself and compost sludge manure(CSM) mixed with sawdust, fowl droppings and urea to the PBS were treated to soybean plants to find the effects of growing characters, yield components, and nutritional compounds in the plant tissues. 1. Percentages of missing plants were 5-9% and 3.6-4.1% in the treatments of PBS and CSM, respectively. After that, the plants were restored to normal conditions. Anyway it is not desirable to use the paper board sludge and immature compost sludge manure in seeding time or to young seedlings. 2. Growth of the plant height was retarded in early growing phase, but it was normal in later stages. And the width and length of the largest leaf, numbers of main stem nodes and pods were not significant among the treatments. 3. The yield intends to increase through the treatments of 1,200, 1,600, and 2,000Kg PBS per 10a. In the CSM treatments with high rate of sawdust, fowl droppings and urea, the numbers of pods and grains were higher than the treatment of high content of PBS. 100-grain and one liter weights were opposite intention. It was suggested that the excess nitrogen amounts from the compost sludge manure than conventional fertilization affected to the yield components. 4. The contents of the main chemical compounds such as N, $P_2O_5$, $K_2O$, Ca, Mg were determined. The concentrations of nitrogen were higher in the treatment of PBS and CSM than none and control. 5. In conclusion, the nutritional effects of PBS were in evidence. To use the sludges, it should be fermented with adequate additives to improve the aeration, C/N ratio, activity of microbial, and other conditions. The sludges could be used to crops as a fertilizers effectively.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.127-134
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• 2012

Microwave remote sensing can help monitor the land surface water cycle, crop growth and soil moisture. A ground-based polarimetric scatterometer has an advantage for continuous crop using multi-polarization and multi-frequencies and various incident angles have been used extensively in a frequency range expanding from L-band to Ka-band. In this study, we analyzed the relationships between L-, C- and X-band signatures and soil moisture content over the whole soybean growth period. Polarimetric backscatter data at L-, C- and X-bands were acquired every 10 minutes. L-band backscattering coefficients were higher than those observed using C- or X-band over the period. Backscattering coefficients for all frequencies and polarizations increased until Day Of Year (DOY) 271 and then decreased until harvesting stage (DOY 294). Time serious of soil moisture content was not a corresponding with backscattering over the whole growth stage, although it increased relatively until early August (R2, DOY 224). We conducted the relationship between the backscattering coefficients of each band and soil moisture content. Backscattering coefficients for all frequencies were not correlated with soil moisture content when considered over the entire stage ($r{\leq}0.50$). However, we found that L-band HH polarization was correlated with soil moisture content (r=0.90) when Leaf Area Index (LAI)<2. Retrieval equations were developed for estimating soil moisture content using L-band HH polarization. Relation between L-HH and soil moisture shows exponential pattern and highly related with soil moisture content ($R^2=0.92$). Results from this study show that backscattering coefficients of radar scatterometer appear effective to estimate soil moisture content.

• Journal of the Korean Society of Food Culture
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• v.14 no.2
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• pp.177-188
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• 1999

15 vegetables were cooked as fresh salad, scalding, steaming, boiling, panbroiling, and hardboiling and retention of vitamin(A, Ascorbic acid, Niacin) and minerals(P, Fe, Mg, Ca, Na, K)were investigated about those cooks during making process. Vitamins were shown as the best retention in fresh salad, while as the worst retention in scalding vegetables. Minerals were determined as the best retention in panbroiled, while as the worst retention in scalding and boiling vegetables. In all vegetables cookings, the order of vegetables which had good retention of vitamins and minerals were doraji>perilla leaf, cabbage>k, radish, cucumber>chamchwi, lettuce> mungbean sprout>spinach, burdock, sedum>carrot, squash>soybean sprout>eggplant. Also Vit.A was kept high retention level in fresh salad, panbroiling, hardboiling, Niacin was remained in fresh salad, hardboiling, steaming, vegetables highly and AsA was kept high level in fresh salad only. And P in panbroiling, steaming, Fe in fresh salad, scalding, boiling, panbroiling, hardboiling, Mg in fresh salad, panbroiling, hardboiling, Ca in fresh salad, steaming, boiling, panbroiling, hardborling, Na in panbroiling, hardboiling and K in fresh salad pan, broiling, hardboiling were retained as high level.