• Korean Journal of Weed Science
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• v.3 no.1
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• pp.23-28
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• 1983

To study ecological characteristics of Eleocharis kuroguwai occuring in Korea its propagules were collected from 6 locations from the northern part to the southern part of Korea (Chuncheon, Suweon, Iri, Jeonju, Gwangiu and Milyang) in 1981, cultured and replanted 3 times (May 20, June 5, June 20) in 1982. They flowered from August 5 to August 27 when they were planted on May 20, and from August 20 to August 27 when they were planted on Tune 20. Plant height, number of tillers and top fresh weight/$m^2$ were 50-90cm, 500-875, and 175-750g, respectively when they were planted on May 20, and 40-70cm, 250-625, 325-625g, respectively when they were planted on June 20. Number of tubers per plant were 0.98-1.98 when they were planted on May 20, and 1.81-2.87 when they were planted on June 20. Eleocharis kuroguwai from Chuncheon or Suweon was more open in plant type, shorter in plant height, narrower in diameter of pedicel and shorter in inflorescence than those from Iri, Jeonju or Gwangju. Each of the local collections may be regarded as different ecotype, based on the above differences in morphology and responses in growth and flowering to the planting dates. The results appear to imply that Eleocharis kuroguwai weeds occurring in various locations of Korea are different one another in competitive avility with rice crop.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.233-240
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• 2017

This experiment was conducted to establish a cultivation system for sorghum in reclaimed soils. Pot experiments were used to test the effects on seedling establishment of sowing depth, soil water content, and soil salinity using seeds of Nampungchal-susu and Hwanggeumchal-susu in reclaimed soil. Field experiments were also conducted to examine differences in growth characteristics and yield production, by sowing time, and planting distance. The result of the pot experiment, examining seedling establishment at various sowing depths revealed that, it was the highest 76.7% when the seeds were sown at a depth of 3 cm. Seedling establishment did not differ with soil water content between 10~30 kpa and at 51~70 kpa. No effects of seed moisture absorption before sowing were observed. Seedling establishment showed no differences with soil salinity below $3.2\;dS\;m^{-1}$, but decreased with Salinity above $4.8\;dS\;m^{-1}$. In field experiments to assess the effects on seedling establishment ratio of sowing time, Nampungchal-susu was revealed to have a high seedling establishment ratio following sowing on June 15. Hwanggeumchal-susu did not exhibits effects of sowing time, on seedling establishment ratio but exhibited higher seedling establishment when in low soil salinity conditions than when sown in high soil salinity conditions. With respect to yield, the yield of the seeds sown on June 15 was higher by 13% for Nampungchal-susu and by 29% for the Hwanggeumchal-susu than that those sown on June 25. With respect to soil salinity, the yield at a soil salinity of $3.2dS\;m^{-1}$ was lower by 23% than that at $1.6dS\;m^{-1}$ or lower for Nampungchal-susu, and was lower by 30% Hwanggeumchal-susu. With respect to planting density, both breeds showed the highest yield at $60{\times}10cm$. These results suggest that a sowing time of June 15 and a seeding distance of $60{\times}10cm$ are appropriate for sorghum in reclaimed land.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.1
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• pp.18-28
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• 2021

The growth period and productivity of cropping system of winter wheat-rice, winter wheat-bean and winter wheat-grain corn for 4 years from 2015 to 2018 were compared at the experimental field of National Institute of Crop Science in Miryang city. The harvest period of winter wheat was in mid-June, and summer crops were sown (transplanted) in late June. In transplanting of rice in late June, there was no difficulty in securing the heading of panicle and the yield of rice, but there was a lot of trouble in sowing wheat in proper time because the harvest time of rice was delayed to early November due to late maturity of rice, particularly in the mid-late maturing cultivar. There was no problem in soybean planting after winter wheat because the proper period of soybean planting is late-June. In addition, there was no problem in winter wheat sowng after soybean because the maturity period of soybean was mid-October. Selection of grain maize in double cropping with winter wheat in terms of growing periods, was desirable because grain maize had the fastest maturity among summer crops. In double cropping of winter wheat-summer crops, wheats combined with soybean and grain maize showed stable yields during three years, but there was a risk of yield declines in the wheat combined with rice in heavy rainfall year. It was possible to secure high yields in three summer crops as yields of rice, soybean, and corn were 600, 350, and 800 kg/10a, respectively. Summer crops with medium maturity was recommended because of no significant difference in yield between medium maturity and medium-late maturity cultivar. Soil physical properties were improved in soils cultivated with soybean and grain maize. Therefore, It was thought that double cropping systems of winter wheat with soybean and grain maize were superior to that of winter wheat with rice in terms of connecting period between winter wheat - summer crops and improvement of soil physical properties, and total income, particularly in soybean.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.89-97
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• 1984

This study was carried out to investigate the effect of seasonal changes on some of the morphological and physiological characteristics, including the photosynthetic abilities and dark respiration, of young ginseng plants due to planting location under shading. The results obtained are as follows: 1. Seedlings and 2-year old plants planted in the back rows appeared to have broader leaf area, and their leaf weight greatly increased in September. Chlorophyll content was significantly reduced in September rather than in June and the plants in the back rows had more chlorophyll content than those in the front rows. 2. There was no difference in the light compensation point between the front and back rows in June, while in September the light compensation point of 2-year old ginseng leaves was much lower for plants in the back rows compared with those in the front rows. A difference in the light saturation point was not noticeable between plants in the front and back rows in June and September. But the light saturation point of 2-year old ginseng leaves at $15^{\circ}C$ was high in June, while it was high at $20^{\circ}C$ high in September. 3. Maximum photosynthetic ability was attained at $15^{\circ}C$ in June and at $20^{\circ}C$ in September. During June no significant difference in photosynthetic ability was found between plants in the front and back rows, but in September the amount of photosynthesis was significantly increased at the leaves of seedlings as well as 2-year old plants planted in the back rows. 4. The optimum temperature for maximum photosynthesis in 2-year old plants ranged from $14.0^{\circ}C$ to $14.5^{\circ}C$ in June and from $19.5^{\circ}C$ to $20.5^{\circ}C$ in September. However, the optimum temperature for maximum photosynthesis in the seedlings was from $21.2^{\circ}C$ to $21.6^{\circ}C$ in September, but a significant difference in the optimum temperature for the maximum photosynthesis in seedlings and 2-year old plants was not noticeable between the front and back rows. 5. The respiration rate was rather high in seedlings compared with 2-year old plants. During September the respiration rate in seedlings was much lower in the back rows than in the front rows. The rate of increase in the respiration of 2-year old plants was higher at September than June. The increase in respiration rate due to temperature was more significant in seedlings than 2-year old plants. 6. In September, the level of $Q_{10}$ in 2-year old plants was much lower than that found in seedlings. During June, 2-year old plants showed lower $Q_{10}$ levels at a temperature difference between $15^{\circ}C$ and $25^{\circ}C$; but in September this occurred at a temperature difference between $20^{\circ}C$ and $30^{\circ}C$.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.118-118
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• 2003

The occurrence of Fusarium wilt in strawberry fields in Korea was assessed from 2001 to 2003. Fusarium wilt was found from June to August in nursery beds, from September to October after planting in production beds, and from January to March during harvest. The symptoms seen were root rots, discolored vascular tissue in the crown and deformation and yellowing of central leaflets. The disease occurred in up to 30％ of plants in 37 of 214 fields surveyed. Fusarium of sporum Schlecht. ex Fr. f. sp. fragariae was frequently isolated from cvs. Dochiodome, Maehyang, Redpearl, Samaberry and Akihime. Factors affecting the occurrence of Fusarium wilt were investigated; infested soils had high salt concentrations, low pH, OM, average P2O5 and exchangeable. Fusarium wilt was more frequent following conventional basal fertilization than after non-nitrogen basal fertilization and more frequent following the use of NH4-N than after NO3-N.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.4
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• pp.335-338
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• 1992

A Cheju-leading mungbean cultivar Seonhwanogdu was seeded at 20, 30, 40, 50 and 60cm row width with within-row plant spacing of 10cm in mid-June of 1988 to 1990 to determine effects of row width on growth and seed yield of mungbean in Cheju area. Initial flowering and maturing dates were not influenced by the row width. Stem length, pods per plant, seeds per pod, 1000-seed weight linearly decreased as row width decreased because planting density increased. The relationship between seed yield and row width was quadratic, and the optimum row width with within-row plant spacing of 10cm for higher yield of mungbean was 40cm in Cheju.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.8
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• pp.1286-1298
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• 2008

This study was attempted to examine the indigo dyeing technique in the latter Joseon Dynasty, and to find diachronic specifics in the indigo dyeing method from 17C to 19C. The results are as follows: First, There were 2 kinds of indigo species-Yoram(Polygonum tinctorium Lour.) and Sungram(Isatis tinctoria L.)-in the latter Joseon Dynasty. Dangram was preferred in particular among Yoram species because of its high dyeing efficiency. Sungram was mainly used for making Jeon(indigo sediment). Second, Yoram cultivation took the following order: Sowing in April${\rightarrow}$planting out in June${\rightarrow}$harvesting leaves in August${\rightarrow}$collecting seeds in September. Sungram had more harvesting times and wider harvesting period than Yoram. Third, all indigo dyeing methods were grouped into two categories, one was temporary dyeing method, the other was permanent dyeing method. Mixture dyeing of the boiled and the raw, raw leaves dyeing, and fermentation dyeing belonged to the temporary dyeing. Jeon dyeing and Gaeogi dyeing belonged to the permanent dyeing. Finally, diachronic specifics from 17C to 19C were as follows: Decline in the mixture dyeing of the boiled and the raw, development in the raw leaves dyeing, continuance of the fermentation dyeing, and naturalization of Jeon dyeing technique.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.100-108
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• 1988

This research was performed to estimate the influence of relative light intensity, planting density, growth period on the growth of fresh and dry weight of the stem and branches, and root in the pretreatment transplanting bed. 1. The growth of fresh and dry weight of the stem and branches per seedling varied in the order of 63%>100%>37%>19% in relative light intensity, and increased with decrease of planting density, and grew highly during the period from May to June. The contribution rates to the growth of fresh and dry weight of the stem and branches were 49.4% and 39.6% in shading treatment, and 4.3% and 6.4% in planting density, and 34.2% in growth period respectively. Of the three factors, that is, shading, density and period, all of the interactions between two factors, and among the three factors in the growth of fresh and dry weight of stem and branches were significant. The growth of fresh and dry weight of root per seedling increased with light intensity and decreased with increase of density. The best growth of root, showed during the period from May to June in fresh weight, but during the period from July and August in dry weight of root. For the three factors, that is, shading, density and growth period, all the interactions between any two factors, and among the three factors in the growth of fresh and dry weight of root were significant.

• Weed & Turfgrass Science
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• v.3 no.4
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• pp.299-304
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• 2014

Effects of false seedbed procedures in organic corn field were evaluated as affected by preparation date and method. False seedbed was prepared at May 7, 14, 21, 28 and June 5 with shallow tillage or flame weeding. Weed suppression rate of each treatment was evaluated 3 weeks after sowing. Optimal false seedbed preparation time was between end of May and early in June. Weed suppression rate of early false seedbed preparation was quiet low. Flaming weed treatment was better than shallow tillage. Weed suppression rate by the second treatment was increased approximately 30-60% compared to $1^{st}$ treatment. Weed suppression rate at 3 weeks after sowing was 70-90% by the second false seedbed preparation. The results showed that the false seedbed technique between end of May and early in June preparation has some potential weed control to reduce weed population during crop growth. Therefore late planting time crop such as corn, sorghum and soybean would be possible to apply false seedbed for organic weed control.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.5 s.112
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• pp.69-82
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• 2005

These studies were carried out (1) to investigate the growth characteristics of Sedum album L. in the field, (2) to propose a suitable shallow peen roof system for this plant, and (3) to evaluate plant growth in the proposed system over the long term. The growth characteristics, such as morphological properties, growth habit, shade tolerance, and flowering, were surveyed. In experimental shallow green-roof systems, the effects of drainage type, substrate type, and soil depth on plant growth were investigated. Then drought tolerance was investigated. After planting Sedum album L. in the proposed system survival rate, cover, and resistance to insects, heal and cold were evaluated for about 2 years. The results of these studies are summarized below. 1. In the field, the aboveground part of Sedum album L. did not die back during the winter. Plant height was 4$\sim$7 cm. Roots were distributed to a depth of 5$\sim$7 cm. Sedum album L. is a compact ground-cover plant that spreads vigorously. Shading condition of less than $30\%$ of full sunlight didn't cause any trouble, but shading conditions above $87\%$ made the shape of the shoots and leaves abnormal. The plant bloomed from June to August and had a rather large compound umbel of white, star-shaped flowers. 2. Two systems, a drainage-blend-10 cm soil depth and a reservoir$\cdot$drainage-blend-15 cm soil depth, performed best in terms of cover, fresh weight, and dry weight. The first has an advantage for green roofs because it is lighter than the latter. 3. In drainage-blend-10 m soil depth and modified reservoir · drainage-blend-10 cm soil depth system no plants died for about 4 months after stopping the irrigation. The visual quality of the latter system was above 5 for 4 months and that of the former was under 5 after 2 months. In the field, however, the drought tolerance of Sedum album L. grown in the former would be enough to withstand the dry season. Considering the urban ecosystem and the importance of healthy growth the modified reservoir $\cdot$ drainage-blend-10 cm soil depth system was finally recommended. This system was composed of a 4 cm thick drainage layer and drain outlets placed at a height of 2.5 cm. 4. In the proposed system, the survival rate was $100\%$, and there was no injury induced by insects and heat. The leaf density decreased a little in winter. Cover increased throughout the year. Sedum album L. was planted with a cover of 72$cm^{2}$ on 3 April 2003; on 16 June 2003 and 15 June 2004, cover was $132.66\pm$5.87 $cm^{2}$(1.8 times) and $886.98\pm$63.51 $cm^{2}$(12.3 times), respectively.