• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.5
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• pp.402-406
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• 2003

Greenhouse and laboratory studies were conducted to determine the allelopathic potentials of extracts or residues from sweet potato (Ipomoea batatas L. (Lam). The extracts applied on filter paper in a Petri dish bioassay significantly inhibited root growth of alfalfa. Aqueous leachates at 40g dry tissue $\textrm{L}^{-1}$ (g $\textrm{L}^{-1}$) from leaves showed the highest inhibition against alfalfa, and followed by stems and roots. Alfalfa root growth was significantly inhibited by methanol extracts of the same plants as the concentration increased. The effect of residue incorporation into soil on seedling growth of com, soybean, barnyard grass and eclipta was examined in the greenhouse, and results showed that the leaf residues at 200g $\textrm{kg}^{-1}$ by plant parts inhibited shoot dry and root dry weights of test plants by 60-80%. By means of HPLC, causative allelopathic substances present in plant parts of sweet potato "Sinyulmi" were identified as coumarin, trans-cinnamic acid, o-coumaric acid, p-coumaric acid, and chlorogenic acid. Total content of these compounds for leaves extracts were detected as the greatest amount in EtOAc fraction, especially trans-cinnamic acid was the greatest component. These results suggest that sweet potato plants have herbicidal potentials, and that their activities exhibit differently depending on plant parts.ant parts.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.159-165
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• 1993

To clarify the effects of sink demand for assimilate on leaf photosynthetic rate, tissue composition, and leaf senescence of soybean [Glycine max (L.) Merr.] J plants, pod and leaf tissues were removed at growth stage $R^3$. Plant responses were measured every 10days from 2 through 42days following treatment. Leaves of depodded plants exhibited increased starch and chlorophyll contents and specific leaf weight. Stomatal resistance was also increased and leaf photosynthetic rate was reduced. Dry weight of vegetative tissues except leaves was increased by pod removal. Leaf removal resulted in a decreased starch content of leaves from 22 to 42days after treatment and that of roots at all sampling times. Specific leaf weight was decreased while leaf photosynthetic rate was increased. Stomatal resistance and chlorophyll content were little affected. Weight per seed was decreased 3.0% by leaf removal. Except for the seed, tissue protein contents were increased by pod removal but decreased by leaf removal, however, seed protein content was not affected by either. Apparent senescence was delayed by depodding. Both apparent and functional senescence were accelerated by leaf removal.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.379-383
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• 2008

Oviposition preference of the bean bug, Riptortus clavatus to sites on a plant and within a field, to plants at different developmental stages, and to different leguminous germplasms was observed. The insect layed its eggs mainly on the back surface of leaf in the upper half of plant in both observation from oviposition cage and soybean field. The egg number in fields were observed at a statistically-same rate in marginal and inside area, and at a median value of one egg per leaf in oviposited leaves. Full seed stage of soybean hardly affected oviposition preference of the insect. A statistically-significant difference in oviposition to different leguminous germplasms was observed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.6
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• pp.411-414
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• 2005

The purpose of this study was to determine proper method for alternative row culture of two varieties to increase seed yield in soybean. The test varieties 'Hwangkeumkong' and 'Taekwangkong' which were planted monoculture of each variety, seeding after mixing same number of seeds of two varieties, 1-row alternation, 2­row alternation, 2-row 'Hwangkeumkong' and 1-row 'Taekwangkong' and 1-row 'Hwangkeumkong' and 2­row 'Taekwangkong'. Alternative planting of 1-row 'Hwangkeumkong' and 1-row 'Taekwangkong' resulted the highest canopy height and reduced lodging most effectively. The terminal and the 9th leaves of 'Taekwangkong' in alternative variety planting showed the higher photosynthetic ability than pure stand of that. Alternative planting of two varieties in every other row increased yield by $17\%$ in 'Hwangkeumkong' and by $8\%$ in 'Taekwangkong'.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.4
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• pp.298-302
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• 2006

A number of field experiments were conducted to assess the role of combined application of nitrogen and sulfur to increase the seed and oil yield of nonnodulating soybean (Glycine max (L) Merr.) cv. PK-416 $(V_1)$ and cv. PK-1024 $(V_2)$. Six combinations of N and S in three replicates each were used for this purpose i.e. $0\;S+23.5kg\;N\;ha^{-1}(T_1);\;0\;S+23.5+20kg\;N \;ha^{-1}(T_2);\;40\;S+23.5kg\;N\;ha^{-1}(T_3);\;40\;S+23.5+20kg\;N\;ha^{-1}(T_4);\;20+20\;S+23.5kg\;N\;ha^{-1}(T_5);\;20+20\;S+23.5+20kg\;N\;ha^l(T_6)$. Nitrate reductase (NR) and ATP-sulphurylase activities in the leaves were measured at various growth stages as the two enzymes catalyze the rate limiting steps of the assimilatory pathways of nitrate and sulphate, respectively. The activities of these enzymes were strongly correlated with seed yield. The higher seed, oil and protein yields were achieved with the treatment $T_6$ in both the cultivars due to optimization of NR activity and ATP-sulphurylase activity, as these parameters were influenced by N and S assimilation. Any variation from this combination was observed to decrease the activity of these enzymes resulting in reductions in the seed, oil and protein yield of soybean.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.277-282
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• 2005

This study was conducted to investigate morphological characteristics and effects of temperature on the development of Piezodorus hybneri on soybean. The unibanded stink bug, Piezodorus hybneri, is a serious insect pest in soybean fields giving damage to seeds in pod and leaves of soybean lowering both quality and yield. Eggs were spherical and laid in two raws on the leaves and pods of soybean plants. Body lengths of females and males were 9.8 mm and 8.7 mm, respectively. Egg hatch rates were better in higher temperature within the range of examined temperatures, which ranged in $81.2{sim}93.2%$. The development periods of eggs at the temperatures of 20, 25, 30 and $35^{\circ}C$ were 10.7, 5.0, 4.0, and 3.0 days, respectively. Mean developmental periods of 1st, 2nd, 3rd, 4th and 5th nymphs at $25^{\circ}C$ were 3.2, 3.4, 3.4, 3.3 and 5.9 days, respectively. Development threshold and effective accumulative temperature were $13.3^{\circ}C$ and 65.5 DD (day degree) for egg stage, $9.9^{\circ}C$ and 322.8 DD for nymph stage, $10.7^{\circ}C$ and 386.4 DD from egg to adult, respectively. Oviposition began from 10 days after emergence at $25^{\circ}C$, and the longevity of female and male were 52.5 and 38.2 days, respectively. Total number of eggs and egg masses laid by a female at $25^{\circ}C$ were 496 and 21.3, respectively, The longevity of adult female was shortened with increasing temperature, whereas the total numbers of eggs laid by a female were decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.358-364
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• 2021

This study was conducted to select a desiccant and determine its concentration for safe usage to improve the harvesting efficiency of soybeans. Soybeans were treated with a desiccant (non-selective herbicide) before and after the maturation stage. The drying effect of the desiccant was higher at earlier treatment times than at the maturation stage, but the difference was not statistically significant. The higher efficacy might be related to the drying process of the leaves and stems, with most of the leaves and stems having already been dried by the time of hand harvesting. Desiccant treatments had no adverse effects on soybean yield, weight of 100 grains, seed quality, or seed germination rate compared with the untreated control. Pesticide residue analysis showed minimum residue concentration to be lower than the tolerance level of pesticide residues. In conclusion, it was confirmed that the desiccant was effective in drying soybean, and that there was no damage to the quality of soybean seeds. In addition to the drying effect, the dessicant treatment also facilitates the removal of weeds that interfere with the mechanical harvest and improves harvesting efficiency through the drying of the growth imbalanced individual. The desiccant treatment is expected to shorten the mechanical harvesting time by 1-2 weeks. It is thought that the selection of the proper cultivation period for other crops after soybean cultivation will be more advantageous.

• The Korean Journal of Mycology
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• v.13 no.1
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• pp.41-47
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• 1985

Eighteen plant residues were added to soil and the amended soil was inoculated with chlamydospores (5,000 cells/g soil) of Fusarium solani causing root rot of ginseng in soil to test the effects of amendment using pea (Pisium sativa L.) as an index plant. Distributional conditions of microogranisms in soil were compared with each other before and after dealing with soil amendment by plant debries. Infection rate by index plant's infectivity showed a higher degree in the treatment of wheat crushed than in control group, and followed by stalk of sweet potato, chinese cabbage, ginseng leaves and soybean pod. On the other hand, the de­creasing order of infection rate was root of garlic, welsh onion, cabbage leaf and stalk, green onion stalk, wheat straw and barley straw. In comparison with control group, the propagules of fungi increased in the treatment of ginseng leaves, soybean ground, wheat crushed, maize stalk, and chinese cabbage, but decreased in the root of garlic, cabbage, and barley straw. Population of total bacteria increased in the treatment of soybean ground, chinese cabbage, radish stalk, welsh onion, and wheat crushed, but decreased in barley straw, tobaco root, ginseng stalk, and wheat straw. The numbers of actinomycetes increased only in the treatment of soybean ground in a comparison with control and also decreased in the garlic stalk and tobaco root. The propagules of Fusarium spp increased in the treatment of chinese cabbage, welsh onion, radish stalk, wheat crushed, and sweet potato stalk, wheat crushed, and sweet potato stalk, but decreased in the treat­ment of wheat straw, ginseng leaves, and cabbage than control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.152-158
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• 2001

In this study, we determined major foods and food groups which contributed to the intake of folate in korean child-bearing women. Folate content of the major foods was also analyzed. A total of 91 healthy women with childbearing potential participated. They were divided into one of three groups by age; A (15∼24 yrs), B(25∼34 yrs) and C (35∼49 yrs). Food consumption data of the subjects were obtained by the 24-hr recall method. The rate of contribution of each food to the total intake of dietary folate was determined. Seventy major foods for folate were selected from the 178 foods they consumed. Two sets of the 70 foods were collected from different markets. After extracting folates from the foods by heating with a HEPES-CHES buffer, the samples were treated with α-amylase, protease and folate intakes was Korean cabbage kimchi followed by laver, soybean sprout, rice, yolmu kimchi, eggs, lettuce, perilla leaves, sea mustard and radish root. Food items that contributed to folate intake were slightly different among the age groups. Although the folate content of Korean cabbage kimchi was 51.6 ㎍/100g, but due to the high amount of intake, it was ranked the first major food prviding folate. High folate foods containing over 100㎍/100g were laver, corn flakes, spinach, mungbean, sesame, quail's eggs, small radish kimchi, kidney beans, leeks and peanuts. However, based on the serving size, spinach, corn flakes, leeks, sweet potato, pepper leaves, quail's eggs, crown daisy, small radish kimchi and perilla leaves contributed above 50㎍ of folate per serving size.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1538-1542
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• 2015

For development of premium sauce, fermented sauces containing ferment (with wheat flour and soybean) and extract(s) of Styela clava (Korean name: miduduk) tunic and/or mulberry leaves and/or onion were prepared, and their angiotensin converting enzyme (ACE) inhibitory and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities were evaluated. All sauces containing extract(s) showed increased ACE inhibitory and DPPH radical scavenging activities. Especially, sauces containing extracts of mulberry leaves and onion showed superior activities, with 26.92% and 40.66% relatively increased ACE inhibitory and DPPH radical scavenging activities, respectively, compared to control (no extract was added). These results suggest that extracts of mulberry leaves and onion could improve antihypertensive and antioxidant activities of fermented sauce.