• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.8-9
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• 2017

Soybean yield has been low and unstable in Japan and other areas in East Asia, despite long history of cultivation. This is contrasting with consistent increase of yield in North and South America. This presentation tries to describe perspective of breaking stagnation of soybean yield in East Asia, considering the factors of the different yields between regions. Large amount of rainfall with occasional dry-spell in the summer is a nature of monsoon climate and as frequently stated excess water is the factor of low and unstable soybean yield. For example, there exists a great deal of field-to-field variation in yield of 'Tanbaguro' soybean, which is reputed for high market value and thus cultivated intensively and this results in low average yield. According to our field survey, a major portion of yield variation occurs in early growth period. Soybean production on drained paddy fields is also vulnerable to drought stress after flowering. An analysis at the above study site demonstrated a substantial field-to-field variation of canopy transpiration activity in the mid-summer, but the variation of pod-set was not as large as that of early growth. As frequently mentioned by the contest winners of good practice farming, avoidance of excess water problem in the early growth period is of greatest importance. A series of technological development took place in Japan in crop management for stable crop establishment and growth, that includes seed-bed preparation with ridge and/or chisel ploughing, adjustment of seed moisture content, seed treatment with mancozeb+metalaxyl and the water table control system, FOEAS. A unique success is seen in the tidal swamp area in South Sumatra with the Saturated Soil Culture (SSC), which is for managing acidity problem of pyrite soils. In 2016, an average yield of $2.4tha^{-1}$ was recorded for a 450 ha area with SSC (Ghulamahdi 2017, personal communication). This is a sort of raised bed culture and thus the moisture condition is kept markedly stable during growth period. For genetic control, too, many attempts are on-going for better emergence and plant growth after emergence under excess water. There seems to exist two aspects of excess water resistance, one related to phytophthora resistance and the other with better growth under excess water. The improvement for the latter is particularly challenging and genomic approach is expected to be effectively utilized. The crop model simulation would estimate/evaluate the impact of environmental and genetic factors. But comprehensive crop models for soybean are mainly for cultivations on upland fields and crop response to excess water is not fully accounted for. A soybean model for production on drained paddy fields under monsoon climate is demanded to coordinate technological development under changing climate. We recently recognized that the yield potential of recent US cultivars is greater than that of Japanese cultivars and this also may be responsible for different yield trends. Cultivar comparisons proved that higher yields are associated with greater biomass production specifically during early seed filling, in which high and well sustained activity of leaf gas exchange is related. In fact, the leaf stomatal conductance is considered to have been improved during last a couple of decades in the USA through selections for high yield in several crop species. It is suspected that priority to product quality of soybean as food crop, especially large seed size in Japan, did not allow efficient improvement of productivity. We also recently found a substantial variation of yielding performance under an environment of Indonesia among divergent cultivars from tropical and temperate regions through in a part biomass productivity. Gas exchange activity again seems to be involved. Unlike in North America where transpiration adjustment is considered necessary to avoid terminal drought, under the monsoon climate with wet summer plants with higher activity of gas exchange than current level might be advantageous. In order to explore higher or better-adjusted canopy function, the methodological development is demanded for canopy-level evaluation of transpiration activity. The stagnation of soybean yield would be broken through controlling variable water environment and breeding efforts to improve the quality-oriented cultivars for stable and high yield.

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.378-383
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• 2018

This study was carried out to investigate the optimum cultivation distance for high yielding cultivation of the new variety of Gomchwi in highland and lowland. The test material was used 'Sammany' variety and the area was cultivated with a highland of 750 m above sea level and a lowland of 20 m above sea level. The planting distance was 5 treatments of $20{\times}20cm$, $20{\times}30cm$, $30{\times}30cm$, $35{\times}40cm$ and $40{\times}40cm$, and the plant was cultivated at 35% shading net in the open field. The annual growth of 'Sammany' variety was higher in the highland than in the lowland, but the number of leaves was higher in the lowland than that in the highland. The leaf number per plant was the highest in the $40{\times}40cm$ plot and the more the planting distance was, the more tendency was. However, the leaf weight per plant was higher in the highland than in the lowland. The number of leaves per 10a were higher in the lowland than that of highland and the tendency was more as the planting distance was narrower. Yields were slightly higher in the highland than that of lowland and the highest treatment plot was 2,983 kg/10a in $20{\times}20cm$. In the second year, the growth was high in the highland, and the highland was high in the leaf number and leaf weight and the same tendency in the yields. Among the planting distances, Yields in both areas were the highest in the $20{\times}20cm$ treatment, with 3,369 kg/10a in lowland and 7,257 kg/10a in highland. The growth of the third year was slightly better in the highland than that of the lowland but the difference was not significant. However, the number of leaves and leaf weight per plant were higher in the lowland than that of highland. And, in terms of leaf number and yield per 10a, it was also higher in the lowland than that in the highland. The narrower the planting distance was increased yields, and the highest yield was 6,051 kg/10a in $20{\times}20cm$. The lowland was high in yield until the third year, but the highland was the highest in the second year and decreased slightly in the third year. The narrower the planting distance in the both areas, the higher the yield, and the leaf size tended to be small.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.143-152
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• 2008

This study was conducted to obtain basic information on mainstem, branch and leaf characteristics related to canopy for development of high yielding cultivar using 70 Korean soybean cultivars developed from 1913 to 2000. Variations of canopy width, branch length, and canopy width/length ratio were higher compared to other characteristics among 12 mainstem and branch characters. Variations of petiole angle, leaflet width/length ratio and compound leaf dry weight were higher than other characteristics among eight leaf characters related to plant canopy. Three classifications of soybean cultivars were used based on usage: I)soy sauce and tofu, II)bean sprout, and III)cooking with rice. Canopy width/length ratio was higher in group III, cooking with rice than group I, soy sauce and tofu, and group II, bean sprout, and there was no difference between the two, group I and group II. The total branch length/main stem height ratio was higher in group II, bean sprout and group III, cooking with rice than group I, soy sauce and tofu. Mainstem and branch characteristics related to plant canopy were classified into four groups by ratio of canopy width/length and total branch length/main stem length, respectively. Soybean cultivars with narrow canopy and high dependence of mainstem were Danweonkong, Keumkangkong, Shelby, and Shinpaldalkong. Soybean cultivars with broad canopy and high dependence of mainstem were Kanglim, Keumkangdaelip, and Jinyulkong, and a cultivar with broad canopy and high dependence of branch were Geomjeongkong 2. Leaflet length/width ratio was lowest in cooking with rice and there was no difference between soy sauce and tofu and bean sprout. Compound leaf area was largest in cooking with rice and smallest in bean sprout. Leaf petiole length was short in bean sprout and there was no difference between soy sauce and tofu and bean sprout. Leaf petiole angle was highest in cooking with rice and lowest in bean sprout. Leaf type was classified into four groups based on leaflet width/length ratio and compound leaf area, respectivly. Buseok and Taekwangkong had an oval leaflet and largest area of compound leaf. Eunhakong and Sohokong had extreme narrow leaflet and smallest area of compound leaf. Leaf petiole type was classified into three and four groups based on leaf petiole length and angle, respectively. A soybean cultivar with the shortest petiole length and smallest petiole angle was Eunhakong and cultivars with short petiole length and large petiole angle were Alchankong, Muhankong, and Pureunkong. A soybean cultivar with long petiole length and small petiole angle was Sinpaldalkong 2. Among a total of 70 Korean soybean cultivars, Eunhakong had an extreme narrow type in leaf, smallest compound leaf area, shortest petiole length, and smallest petiole angle of compound leaf.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.29 no.1
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• pp.56-76
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• 2024

We for the first time made a successful longest continuous sectional observation in the East Sea by an underwater glider during 95 days from September 18 to December 21 2020 in the Korea along the 106 Line (129.1 °E ~ 131.5 °E at 37.9 °N) of the regular shipboard measurements by the National Institute of Fishery Science (NIFS) and obtained twelve hydrographic sections with high spatiotemporal resolution. The glider was deployed at 129.1 °E in September 18 and conducted 88-days flight from September 19 to December 15 2020, yielding twelve hydrographic sections, and then recovered at 129.2 °E in December 21 after the last 6 days virtual mooring operation. During the total traveled distance of 2550 km, the estimated deviation from the predetermined zonal path had an average RMS distance of 262 m. Based on these high-resolution long-term glider measurements, we conducted a comparative study with the bi-monthly NIFS measurements in terms of spatial and temporal resolutions, and found distinguished features. One is that spatial features of sub-mesoscale such as sub-mesoscale frontal structure and intensified thermocline were detected only in the glider measurements, mainly due to glider's high spatial resolution. The other is the detection of intramonthly variations from the weekly time series of temperature and salinity, which were extracted from glider's continuous sections. Lastly, there were deviations and bias in measurements from both platforms. We argued these deviations in terms of the time scale of variation, the spatial scale of fixed-point observation, and the calibration status of CTD devices of both platforms.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.17
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• pp.45-78
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• 1974

To provide useful information for developing new high yielding soybean varieties and for improving cultural practices, an investigation was made on variation of dry matter production and on relationship among several agronomic characters of soybean plants grown under different planting times and densities as well as under different fertilizer levels, using Kwang-kyo, Dong puk-tae, and Suke ＃ 51 as determinate types and Shelby, SRF-300 and Harosoy as indeterminate types at the Crop Experiment Station during the period of 1972 and 1973. The results obtained were summarized as follow: 1. The dry weight, CGR and LAI at the initial flowering stage were high in the high plant population irrespective of varieties, planting times, and fertilizer levels. However, those characters of the indeterminate type were lower than those of the determinate types. The same characters of the indererminate type at the terminal leaf stage were either same or higher than those of the determinate types. 2. The dry weight of the determinate type at the initial flowering stage was similar to the indeterminate, type, when planting times were May 21 or June 15. The dry weights of both types of varieties were low when planted on July 10. When fertilizer levels were increased, the CGR, dry weight and LAI at the initial flowering stages were also increased. 3. Even though significant differences of LAI were obtained among the varieties within the same plant type, the indeterminate type was in general lower than that of the determinate type regardless of planting time and densities, or fertilizer levels, while the yield of the indeterminate type was comparable to the yield of the determinate type. 4. The high degree of leaf- and petiole-fall at the greenbean stage was highly associated with early planting and high levels of fertilizers. However, less amount of leaf- or petiole-fall was found when planted on July 10 or under low plant population. 5. The percent of stem weight was high under higher plant population, while the percent of leaf weight was high under lower plant population. When planting time was late, the percent of stem and petiole weight were reduced, while the leaf weight was increased. 6. The percent of pod weight of the determinate type at the terminal leaf stage was about 2% when planted on May 21, about 8% when planted on June 15, and about 9% when planted on July 10. The percent of pod weight of the indeterminate type at the terminal leaf stage were about 6 % when planted on May 21, 14% when planted on June 15 and 21% when planted on July 10. 7. Kwang kyo showed less degree of leaf-fall even when lodged due to high levels of fertilizer applied, while SRF-300 showed great damage due to lodging. 8. High yields were obtained when planted on May 21, but there were little yield differences between yields from May 21 and June 15 plantings. The reduction of yield due to late planting of July 10 was less apparent in the determinate type of varieties, while it was high in the indeterminate type. 9. The optimum plant population per are for high yield was 1, 250 to 2, 500 plants when planted on May 21, 2, 500 plants when planted on June 15, and 3, 333 plants when planted on July 10. 10. High correlation coefficients were obtained between dry matter weight and LAI at the terminal leaf stages, and between the dry matter weight and yield at the greenbean stages. The optimum dry weight for high yield in the determinate type was expected to be 25 kg. per are at the initial flowering stage and 50 kg. per are at the terminal leaf stage. In the indeterminate type the LAI and dry weight at the greenbean stage were 4 to 5 and 80 kg. per are, respectively. 11. Under the high plant population plant height was increased, while the stem diameter and the number of nodes and branches were reduced. Consequently, the percent of mainstem to main stem plus branches were increased, and the length of internode was also elongated. The ratios of stem weight, number of nodes and pods, and yield of main stem were increased when high plant population was associated with the early planting. The percent of main stem to branches for the indeterminate type was higher than that of the determinate type. 12. Under the high plant densities and late planting, the percent of the pod number and yields of main stem were increased, indicating that varieties with no or less branches were better adaptable under such conditions. 13. High degree of simple correlation coefficients was obtained between the LAI at the initial flowering stage and terminal leaf stage, and the total node number, dry matter and dry stem weight of both determinate and indeterminate types. Even though no significant correlation was found between the LAI at the initial flowering stage of the determinate type and the stem length and pod number per are, highly significant correlation coefficients were obtained between such characters in the indeterminate type of varieties. 14. The dry matter was positively correlated with the LAI, CGR, stem length, and pod number, node number and dry stem weight per are, while no significant correlation was found between the dry matter and stem diameter. 15. The correlation coefficients between lodging index and the LAI, dry weight, stem length and dry stem weight were highly significant. Negative correlation was obtained for the indeterminate type between the stem diameter and lodging index. The correlation coefficient between the stem diameter and lodging index was non-significant for the determinate type, while positive correlation was obtained between the yield and lodging index in the determinate type. The lodging index was also positively correlated with average length of internode of main stem. 16. The 100 seed weight appeared to be lowered under the high plant population and no fertilizer condition, and when planted late. Apparent differences of 100 seed weight were found between main stem and branches, being higher for the main stem than for the branches. 17. No variation of protein content was found due to different cultural practices. However, the oil content was apparently reduced when planted late.

• KSBB Journal
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• v.25 no.2
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• pp.155-166
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• 2010

Studies on the production of cell-wall bound innerpolysaccharides (IPS) (soluble ${\beta}$-D-glucan) have been performed by use of suspended myelial cultures of Inonotus obliquus. This product has promising potentials as an effective antidiabetic as well as an immunostimulating agents. As a first step to enhanced production of IPS, Intensive strain improvement programs were carried out by obtaining a large amounts of protoplasts for the isolation of single cell colonies. Rapid and large screening of high-yielding producers was possible because about fivefold higher amount of protoplasts ($2.3{\times}10^6$ protoplasts/mL) could be recovered with relatively high regeneration rates of $10^{-2}{\sim}10^{-3}$ by applying a modified filtration method, as compared to the previously used trapping method. A basic protocol necessary for UV-mutation of the protoplasts was also developed, resulting in several overproducing variants with good fermentation properties. Since the amount of IPS extracted from the mycelial cell walls of I. obliquus turned out to be almost constant per g DCW, increase in cell mass was considered the most important factor for the enhancement in IPS production. Therefore, attempts were made to screen mutant cells showing rapid mycelial growth rate in the final suspended cultures. Notably, the mutant strains showing an active cellgrowth in the preceding solid growth cultures were observed to produce higher amount of IPS in the suspended fermentations as well. A striking mutant, OBLQ756-15-5 strain, obtained from the survivors of a harsh UV-treated condition (97% death rate) was found to stably produce as high cell mass as 22 g DCW/L in the final fermentations. Currently, this strain is being tested for development of a scaled-up fermentation process for mass production of IPS.

• Journal of Mushroom
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• v.17 no.4
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• pp.205-210
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• 2019

This study was conducted to elucidate the optimal nitrogen content for each variety of oyster mushroom (Pleurotus ostreatus) by investigating the change in the characteristics of fruiting body according to the nitrogen content of the sawdust media, and to use the results as the basic data for cultivation of high quality oyster mushroom. The nitrogen content was adjusted to 1.3%, 1.6%, 1.8% and 2.3%, and at each condition, mycelial growth was observed, which showed that the nitrogen content did not affect the rate of mycelial growth and density substantially. In the investigation of the characteristics of fruiting body, at the 1.8% nitrogen content, Chunchu No.2 showed the pileus diameter of 27 mm, and the stipe diameter and length of 11 mm and 61 mm, respectively, and the measurement of its color values revealed that the brightness of the pileus and the stipe was 31 and 80, respectively, offering the best commercial value, and yielding 25 valid stipes, which was the largest number. Likewise, at the 1.8% nitrogen content, Heuktari also showed the excellent growth characteristics including the pileus diameter of 29 mm and the stipe diameter and length of 10 mm and 68 mm, respectively, and the superb color values of the brightness of 37 at the pileus and 78 at the stipe. Moreover, the number of valid stipes was also found to be the highest with 19. In terms of morphological characteristics such as the pileus diameter and color, Soltari also produced the best mushrooms at the 1.8% nitrogen content and the number of valid stipes was high with 22. In summary, irrespective of varieties of oyster mushroom, high quality products could be cultivated at the nitrogen content of 1.8%.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.640-644
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• 2009

A new sprout-soybean cultivar, "Sohwang" was developed at the National Institute of Crop Science (NICS) in 2008. "Sohwang" was selected from a cross between Pungsan and Pungsan/Nattosan. The preliminary, advanced, and regional yield trials to evaluate the performance of Iksan 58 were carried out from 2004 to 2008. This cultivar has a determinate growth habit with purple flower, grayish brown pubescence, yellow seed coat, Yellow hilum, lanceolate leaflet shape and small seed size (8.5 grams per 100 seeds). The maturity date of "Sohwang" is 10 days earlier than the check variety, "Pungsan". It has a good seed quality for soybean-sprout. The soybean-sprouts grown from "Sohwang" have high isoflavone ($3,041{\mu}g/g$)contents. This cultivar has resistance to soybean mosaic virus (SMV) and necrotic symptom (SMV-N), and other most troublesome soybean diseases which are bacterial pustule and black root rot. Especially, "Sohwang" has useful characteristics, such as lodging and shattering resistance. The average yield of "Sohwang" was 2.69 ton per hectare in the carried out for three years from 2006 to 2008 regional yield trials(RYT) for double cropping.

• Korean Journal of Breeding Science
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• v.41 no.1
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• pp.56-60
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• 2009

A new naked oat cultivar Daeyang (Avena sativa L.) was developed by Department of Rice and Winter Cereal Crop, NICS, RDA in 2007. It was derived from a cross between 'FLX446-1-84-Q1'. and 'SO92004-B-3-3-5-7'. The FLX446-1-84-Q1, a naked oat cultivar from USA, is early heading and has good seed quality, while the SO92004-B-3-3-5-7, a covered oat breeding line, has a high yield with large grain. Subsequent generations were handled in a bulk method and pedigree selection program, and the SO97013-B-16-4 was selected based on agronomic performance in 2001. The line showed both high yield and good husking rate of seed in the yield trial tested at Suwon from 2002 to 2003, being designated as Gwiri51. The Gwiri51 was subsequently evaluated for winter hardiness, earliness, and yield in four locations, Gimje, Iksan, Jeongeup, and Jinju, from 2004 to 2007 and was designated as "Daeyang" and released. Its heading date was May 8 and maturing time was June 14 in a paddy field condition. The new cultivar Daeyang had 97 cm of culm length and 25.2 cm of spike length, 644 spikes per $m^2$, 65 grains per spike, 30.3 g of 1,000-grain weight, and 635 g of test weight. Daeyang showed better winter hardiness than that of the check cultivar 'Sunyang', and similar seed quality to the check cultivar in respect to percent content crude protein and $\beta$-glucan. However, it showed higher husking rate than the check cultivar. Grain yield of Daeyang in the regional yield trial for 4 years were averaged 4.18 MT $ha^{-1}$, which was 20% higher than that of the check cultivar Sunyang. Fall sowing cropping is recommended only in a south area where daily minimum mean temperatures are averaged higher than $-4^{\circ}C$ in January, and should be excluded in mountain area where frost damage is presumable.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.324-327
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• 2008

'Onnuri' is a japonica rice cultivar developed from the cross between 'Milyang 165' and HR14732-B-67-2-3 at Honam Agricultural Research Institute (HARI), NICS, RDA, in 2005. This cultivar has a short grain shape and about 121 days growth duration from transplanting to harvesting in Korean climate condition. In reaction to biotic and abiotic stresses, it shows resistance to blast, bacterial blight pathogen from $K_1$ to $K_3$ and stripe virus, but susceptible to other major diseases and insect pests. The milled kernel of 'Onnuri' is translucent with non-glutinous endosperm. It has about 18.6% of amylose content and better palatability of cooked rice compared with 'Chucheongbyeo' cultivated in Kyunggi province. The milled rice yield of 'Onnuri' is about 5.94 MT/ha under the standard fertilizer level of the ordinary transplanting cultivation. 'Onnuri' would be adaptable to southern plain of Cheonan, middle-northern plain, and southern mid-mountainous of Korea.